Transcriber's note: A few typographical errors have been corrected: theyare listed at the end of the text. The errata on pp. 70, 118, 162, 310, 352, 367 & 407 have been applied to the text. * * * * * _PHILOSOPHICAL_ TRANSACTIONS: GIVING SOME ACCOMPT OF THE PRESENT Undertakings, Studies, and Labours OF THE INGENIOUS IN MANY CONSIDERABLE PARTS OF THE WORLD _Vol I. _ For _Anno_ 1665, and 1666. In the _SAVOY_, Printed by _T. N. _ for _John Martyn_ at the Bell, a little without_Temple-Bar_, and _James Allestry_ in _Duck-Lane_, Printers to the _Royal Society_. * * * * * TO THE Royal Society. _It will not become me, to adde any Attributes to a Title, which has aFulness of Lustre from his _Majesties_ Denomination. _ _In these Rude Collections, which are onely the Gleanings of my _private_diversions in broken hours, it may appear, that many Minds and Hands are inmany places industriously employed, under Your Countenance, and by YourExample, in the pursuit of those Excellent Ends, which belong to YourHeroical Undertakings. _ _Some of these are but the Intimations of large Compilements. And someEminent Members of Your _Society_, have obliged the Learned World withIncomparable _Volumes_, which are not herein mention'd, because they werefinisht, and in great Reputation abroad, before I entred upon this Taske. And no small Number are at present engaged for those weighty Productions, which require _both_ Time and Assistance, for their due Maturity. So thatno man can from these Glimpses of Light take any just Measure of YourPerformances, or of Your Prosecutions; but every man may perhaps receivesome benefit from these Parcels, which I guessed to be somewhat conformableto Your Design. _ _This is my Solicitude, That, as I ought not to be unfaithful to thoseCounsels you have committed to my Trust, so also that I may not altogetherwaste any minutes of the leasure you afford me. And thus have I made thebest use of some of them, that I could devise; To spread abroadEncouragements, Inquiries, Directions, and Patterns, that may animate, anddraw on_ Universal Assistances. _The _Great God_ prosper You in the Noble Engagement of Dispersing the trueLustre of his Glorious Works, and the Happy Inventions of obliging Men allover the World, to the General Benefit of Mankind: So wishes with realAffections, _ Your humble and obedient Servant _HENRY OLDENBURG. _ {1} * * * * * _Numb. _ 1. PHILOSOPHICAL_TRANSACTIONS. _ * * * * * _Munday_, _March_ 6. 1664/5. * * * * * The Contents. _An Introduction to this Tract. An Accompt of the Improvement of _Optick Glasses_ at _Rome_. Of the Observation made in _England_, of a Spot in one of the Belts of the Planet _Jupiter_. Of the motion of the late _Comet_ prædicted. The Heads of many New Observations and Experiments, in order to an Experimental _History of Cold_; together with some _Thermometrical_ Discourses and Experiments. A Relation of a very odd Monstrous _Calf_. Of a peculiar _Lead-Ore_ in _Germany_, very useful for Essays. Of an _Hungarian Bolus_, of the same effect with the _Bolus Armenus_. Of the New _American_ Whale-fishing about the _Bermudas_. A Narative concerning the success of the _Pendulum-watches_ at Sea for the _Longitudes_; and the Grant of a _Patent_ thereupon. A Catalogue of the Philosophical Books publisht by _Monsieur de Fermat_, Counsellour at _Tholouse_, lately dead. _ * * * * * _The Introduction. _ Whereas there is nothing more necessary for promoting the improvement ofPhilosophical Matters, than the communicating to such, as apply theirStudies and Endeavours that way, such things as are discovered or put inpractise by others, it is therefore thought fit to employ the _Press_, asthe most proper way to gratifie those, whose engagement in such Studies, and delight in the advancement of Learning and profitable Discoveries, dothentitle them to the knowledge of what this Kingdom, or other parts of theWorld, do, from time to time, afford, as well {2} of the progress of theStudies, Labours, and attempts of the Curious and learned in things of thiskind, as of their compleat Discoveries and performances: To the end, thatsuch Productions being clearly and truly communicated, desires after solidand usefull knowledge may be further entertained, ingenious Endeavours andUndertakings cherished, and those, addicted to and conversant in suchmatters, may be invited and encouraged to search, try, and find out newthings, impart their knowledge to one another, and contribute what they canto the Grand design of improving Natural knowledge, and perfecting all_Philosophical Arts_, and _Sciences_. All for the Glory of God, the Honourand Advantage of these Kingdoms, and the Universal Good of Mankind. * * * * * _An Accompt of the improvement of_ Optick Glasses. There came lately from _Paris_ a Relation, concerning the Improvement of_Optick Glasses_, not long since attempted at _Rome_ by Signor _GiuseppeCampani_, and by him discoursed of, in a Book, Entituled, _Ragguaglio dinuoue Osservationi_, lately printed in the said City, but not yettransmitted into these parts; wherein these following particulars, according to the Intelligence, which was sent hither, are contained. The _First_ regardeth the excellency of the long _Telescopes_, made by thesaid _Campani_, who pretends to have found a way to work great _OptickGlasses_ with a Turne-tool, without any Mould: And whereas hitherto it hathbeen found by Experience, that _small_ Glasses are in proportion better tosee with, upon the Earth, than the _great_ ones; that Author affirms, thathis are equally good for the Earth, and for making Observations in theHeavens. Besides, he useth three Eye-Glasses for his great _Telescopes_, without finding any _Iris_, or such Rain-bow colours, as do usually appearin ordinary Glasses, and prove an impediment to Observations. The _Second_, concerns the _Circle of Saturn_, in which he hath observednothing, but what confirms Monsieur _Christian Huygens de Zulichem_ hisSysteme of that Planet, published by that worthy Gentleman in the year, 1659. {3} The _Third_, respects _Jupiter_, wherein _Campani_ affirms he hath observedby the goodness of his Glasses, certain _protuberancies_ and_inequalities_, much greater than those that have been seen thereinhitherto. He addeth, that he is now observing, whether those sallies in thesaid _Planet_ do not change their scituation, which if they should be foundto do, he judgeth, that _Jupiter_ might then be said to turn upon his_Axe_; which, in his opinion, would serve much to confirm the opinion of_Copernicus_. Besides this, he affirms, he hath remarked in the _Belts_ of_Jupiter_, the shaddows of his _satellites_, and followed them, and atlength seen them emerge out of his Disk. * * * * * _A Spot in one of the Belts of Jupiter. _ The Ingenious Mr. _Hook_ did, some moneths since, intimate to a friend ofhis, that he had, with an excellent twelve foot Telescope, observed, somedays before, he than spoke of it, (_videl. _ on the ninth of _May_, 1664, about 9 of the clock at night) a small Spot in the biggest of the 3obscurer _Belts_ of _Jupiter_, and that, observing it from time to time, hefound, that within 2 hours after, the said Spot had moved from East toWest, about half the length of the Diameter of _Jupiter_. * * * * * _The Motion of the late Comet prædicted. _ There was lately sent to one of the _Secretaries_ of the _Royal Society_ aPacket, containing some Copies of a Printed Paper, Entituled, The_Ephemerides_ of the _Comet_, made by the same Person, that sent it, called_Monsieur Auzout_, a _French_ Gentleman of no ordinary Merit and Learning, who desired, that a couple of them might be recommended to the said_Society_, and one to their _President_, and another to his Highness Prince_Rupert_, and the rest to some other Persons, nominated by him in a Letterthat accompanied this present, and known abroad for their singularabilities and knowledge in Philosophical Matters. The end of theCommunication of this Paper was, That, the motion of the _Comet_, that hathlately appeared, having been prædicted by the said _Monsieur {4} Auzout_, after he had seen it (as himself affirms) but 4 or 5 times: the _Virtuosi_of _England_, among others, might compare also their Observations with his_Ephemerides_, either to confirm the _Hypothesis_, upon which the _Author_had before hand calculated the way of this Star, or to undeceive him, if hebe in a mistake. The said Author Dedicateth these his conceptions to themost Christian King, telling him, that he presents Him with a design, whichnever yet was undertaken by any _Astronomer_, all the World having beenhitherto perswaded, that the motions of _Comets_ were so irregular, thatthey could not be reduced to any Laws, and men having contented themselves, to observe exactly the places, through which they did pass; but no man, that he knows, having been so bold as to venture to foretel the places, through which they should pass, and where they should cease to appear:Whereas he exhibites here the _Ephemerides_, determining day by day, inwhat place of the Heavens this _Comet_ shall be, at what hour it shall bein its _Meridian_, and at what hour it shall set; untill its too greatremoteness, or the approach of the Sun, hide it from our eyes. Descendingto particulars, he saith, that this Star, being disengaged from the beamsof the Sun might have been observed, if his conjectures be good, ever sinceit hath been of 17 or 18 degrees _Southern Latitude_, and that about themiddle of _November_ last, and sooner, unless it have been too small: Thathowever it hath been seen in _Holland_ ever since the _2d. _ of _December_last, at which time, according to his reckoning, the Diurnal motion of the_Comet_ should already amount to 17 or 18 minutes. He finds, that this Starmoveth _just enough_ in the Plan of a _Great Circle_, which inclineth tothe _Equinoctial_ about 30 degrees, and to the _Ecliptick_ about 49d. Or49½ cutting the _Equator_ at about 45_d_½, and the _Ecliptick_ at the 28_d_of _Aries_, or a little more. He saith _just enough_, because he thinks, there may perhaps be some _parallaxe_, which he wisheth could bedetermined. Hence, (_so he goes on_) every one who pleaseth, may see, in tracing the_Comet_ upon the _Globe_, through, or by which Stars it hath passed andshall pass; adding, that there will be neither cause to wonder, that havingdescended to about 6. Deg. Beneath the _Tropick_ of _Capricorn_, he hathremounted afterwards, and shall go {5} on ascending so, as to pass the_Æquinoctial_, and perhaps proceed to 15. Degrees _Northern Declination_, if it do not disappear before that time, by reason of its remoteness: Norto believe, that there have been two _Comets_, upon its being seen againthe 31. Of _December_; since, according to him, it ought to have been so, if it continue to move in a _Great Circle_. Having hereupon shewed, how the motion is to be traced upon the _Globe_, hefinds, that, according to his Calculation, this _Comet_ was to pass the_Tropick_ of _Capricorn_ about the 16 of _December_, and being entred intothe Sign of _Virgo_ on the 20. Of the same month, and having been in_Quadrat_ with the _Sun_, it should still descend, until the 26 of_December_ in the morning, and then enter into _Leo_; that having entred, the 28. Of the same month, into _Cancer_, and been, a little after thattime, in its greatest Inclination to the _Ecliptick_, vid in the 28. Degreeof _Leo_, it was to repass the _Southern Tropick_, over against the _littleDogg_, on the 29. Of _December_ about 9 or 10 of the clock in the morning, after it had been opposite to the _Sun_ 2. Or 3. Hours before; and that onthe 29. Of _December_ in the evening it should be in _Gemini_; and at thevery beginning of the New year, enter into _Taurus_. After this, our Author finds, that this _Comet_, according to his account, should pass the _Æquator_, on the 4. Of _January_ before noon, and thatabout 5. Or 6. Of the clock in the evening of that day it was to come intothe jaw of the _Whale_, and the 9. Of the same, at 6. Of the clock itshould come close to the small Star of the _Whale_, which is in its way, alittle below. At length he finds that it was to enter into _Aries_ on the12. Of _January_, and to cut the _Ecliptick_ on the 16. Of the same monthabout noon, at which time it was to be again in _Quadrat_ with the _Sun_, whence drawing a little to above the _Northern Line_ of _Pisces_, it shouldin his opinion cease to appear a little beyond that place, without going asfar as to the middle of _Aries_, if so be that its remoteness make it notdisappear sooner. He continueth, and saith, that this _Comet_ shall not arrive to the placeover against the _Line_ of _Pisces_ till the 10 of _February_, & that thenits _Diurnal_ motion shall not exceed 8 minutes, and not 5 minutes aboutthe 20 of the same month: and that in the {6} beginning of _March_, if wesee it so long, the said motion shall not exceed 4 minutes, and so shall bestill diminishing; except the _Comet_ become _Retrograde_, which, as veryimportant, he would have well observed; as also, whether its motion will beabout the end more or less swift, than he hath calculated it. He subjoyneth, that the greatest way, which this Star could make in 24. Hours, hath been 13. D. 25'; and in one houre, about 34'; and thinking itprobable, that about the time, when it made so much way, it should benearest to the _Earth_, he concludeth that its motion in 24. Hours must be, in its least distance from the _Earth_, as about 3. To 14, or 1. To 4-2/3, and that its motion in one hour was to be to the same least distance, asabout 1. To 102-1/7. But that, which he judgeth most remarkable, is, that he found by hisCalculation, that the said least distance should be on the 29. Of_December_, when the _Comet_ was opposite to the Sun; which he does notknow whether it may not serve to decide the grand Question concerning the_Motion of the Earth_. He taketh further notice, that the _Tayl_ of the _Comet_ was to turn_Westward_, with a point to the _North_, until the 29. Of _December_, atwhich time it was to be opposite to the _Sun_, and that then the said_Tayl_ was to look directly _North_; but that, after that time, the _Tayl_was to turn _Eastward_, and continue to do so, until it disappear; and thatit shall draw a little towards the _North_, until the 8. Or 10. Of_February_, at which time the _Tayl_ is to be parallel to the _Æquator_, asif the _Comet_ be _yet_ seen for some time after, the _Tayl_ shall go alittle lower towards the _South_, but grow smaller. He finds by his _Hypothesis_, that on the 2. Of _December_, which is thefirst observation, that he hath heard of, this Star was to be about 7. Times more remote from the _Earth_, than when it was in its _Perigeum_; andthat it will be again in an equall remoteness from the _Earth_, on the 27. Of _January_, so that he is of opinion, that in case this _Comet_ have notbeen seen before the 2. Of _December_, it will not be seen any more afterthe 27. Of _January_. He wishes above all things, that it might be very exactly observed, at whatAngle the way of the _Comet_ cuts the _Æquator_, and, most of all, the_Ecliptick_, that so it may be seen, whether {7} there hath not been some_Parallaxe_ in the _Circle_ of his Motion; as also, that some observationscould be had of its greatest descent beneath the _Tropick of Capricorn_ inthe more _Southern_ parts, where he saith it would have been without_Refractions_; Moreover of the Time, when it hath been in _Quadrat_ withthe _Sun_ about the 20 of _December_; and that also very exact Observationmight be made of the time of its being again in _Quadrat_ with the _Sun_, which, according to him, was to be _January_ 16. He wishes also, that some in _Madagascar_ may have observed this Star;Seeing that it began to appear over the middle of that _Island_, and passedtwice over their heads; he judgeth, that they have seen it before us. Andhe wisheth lastly, that there were some intelligent person in _Guiana_ toobserve it there, seeing that within a few daies, according to hisreckoning, it will pass over their Heads, and will not remove from thencebut 8 or 10 degrees Northward, where he saith, it will disappear; thinkingit improbable, that it can still appear, after the _Sun_ shall have passedit. This Account beareth date of the 2. _January_, new stile, 1665. And theAuthor thereof addeth this Note, That, seeing it could not be printed nordistributed so soon as he desired, he hath had the opportunity to verifieit by some Observations, from which he affirms he hath found no sensibledifference; or, if there be, that it proceeds only from thence, that theStars have advanced, since his _Globe_ was made. He concludeth, that ifthis continue, and the first Observations do likewise agree, or that thedifferences do arrive within the Times ghessed by him, that he hopes, heshall determine both the _Distance_ and the _Magnitude_ of this _Comet_;and that perhaps one may be enabled to decide the Question of the _Motionof the Earth_. In the interim, he assureth, that he hath not changed theleast number in his Calculations, and that _Monsieur Huygens_, and severalFrench Gentlemen, to whom he saith, he hath given them long since, can bearhim witness that he hath done so; as also many other friends of his, whosaw upon his _Globe_, several daies before, the way of the _Comet_ from dayto day. Thus for the _Parisian_ Account of the Comet, which is here inserted atlarge, that the intelligent and curious in _England_ may {8} compare theirObservations therewith, either to verifie these _Prædictions_, or to shewwherein they differ; which is (as was also hinted above) the design of this_Philosophical Prophet_ in dispersing his Conceptions, who declarethhimself ready, in case he be mistaken in his reckoning, to learn another_Hypothesis_, to explicate these admirable appearances by. * * * * * _An Experimental History of Cold. _ There is in the Press, a New _Treatise_, entituled, _New Observations andExperiments in order to an Experimental History of Cold_, begun by thatNoble Philosopher, Mr. _Robert Boyle_, and in great part already Printed;He did lately very obligingly present several Copies of so much as wasPrinted, to the _Royal Society_, with a desire that some of the Membersthereof might be engaged to peruse the Book, and select out of it fortrial, the hints of such Experiments, as the _Author_ there wisheth mightbe either yet made or prosecuted. The Heads thereof are, 1. Experiments touching Bodies capable of Freezing others. 2. Experiments and Observations touching Bodies Disposed to be Frozen. 3. Experiments touching Bodies, Indisposed to be Frozen. 4. Experiments and Observations touching the Degrees of Cold in severalBodies. 5. Experiments touching the Tendency of Cold Upwards or Downwards. 6. Experiments and Observations touching the Preservation and Destructionof (Eggs, Apples, and other) Bodies by Cold. 7. Experiments touching the Expansion of Water and Aqueous Liquors byFreezing. 8. Experiments touching the Contraction of Liquors by Cold. 9. Experiments in Consort, touching the Bubbles, from which the Levity ofIce is supposed to proceed. 10. Experiments about the Measure of the Expansion and the Contraction ofLiquors by Cold. 11. Experiments touching the Expansive Force of Freezing Water. 12. Experiments touching a New way of estimating the {9} Expansive force ofCongelation, and of highly compressing Air without Engines. 13. Experiments and Observations touching the Sphere of Activity of Cold. 14. Experiments touching differing _Mediums_, through which Cold may bediffused. 15. Experiments and Observations touching Ice. 16. Experiments and Observations touching the duration of Ice and Snow, andthe destroying of them by the Air, and several Liquors. 17. Considerations and Experiments touching the _Primum Frigidum_. 18. Experiments and Observations touching the Coldness and Temperature ofthe Air. 19. Of the strange Effects of Cold. 20. Experiments touching the weight of Bodies frozen and unfrozen. 21. Promiscuous Experiments and Observations concerning Cold. This Treatise will be dispatched within a very short time, and would havebeen so, ere this, if the extremity of the late Frost had not stopt thePress. It will be accompanied with some Discourses of the same _Author_, concerning _New Thermometrical Experiments and Thoughts_, as also, with anExercitation about the _Doctrine of the Antiperistasis_: In the formerwhereof is _first_ proposed this _Paradox_, That not only our Senses, butcommon Weather-glasses, may mis-inform us about Cold. _Next_, there arecontained in this part, New Observations about the deficiencies ofWeather-glasses, together with some considerations touching the New or_Hermetrical_ Thermometers. _Lastly_, they deliver another _Paradox_, touching the cause of the Condensation of the Air, and Ascent of water bycold in common Weather-glasses. The latter piece of this part contains anExamen of _Antiperistasis_, as it is wont to be _taught_ and _proved;_ Ofall which there will, perhaps, a fuller account be given by the Next. {10} * * * * * _An Account of a very odd Monstrous Calf. _ By the same Noble person was lately communicated to the _Royal Society_ anaccount of a very Odd Monstrous Birth, produced at _Limmington_ in_Hampshire_, where a Butcher, having caused a Cow (which cast her Calf theyear before) to be covered, that she might the sooner be fatted, killed herwhen fat, and opening the Womb, which he found heavy to admiration, saw init a Calf, which had begun to have hair, whose hinder Leggs had no Joynts, and whose Tongue was, _Cerberus_-like, triple, to each side of his Mouthone, and one in the midst: Between the Fore-leggs and the Hinder-leggs wasa great Stone, on which the Calf rid: the _Sternum_, or that part of theBreast, where the Ribs lye, was also perfect Stone; and the Stone, on whichit rid, weighed twenty pounds and a half; the outside of the Stone was ofGrenish colour, but some small parts being broken off, it appeared aperfect Free-stone. The Stone, according to the Letter of Mr. _DavidThomas_, who sent this Account to Mr. _Boyle_, is with Doctor _Haughteyn_of _Salisbury_, to whom he also referreth for further Information. * * * * * _Of a peculiar Lead-Ore of _Germany_, and the Use thereof. _ There was, not long since, sent hither out of _Germany_ from an inquisitivePhysician, a List of several _Minerals_ and _Earths_ of that Country, andof _Hungary_, together with a _Specimen_ of each of them: among which therewas a kind of _Lead-Ore_ which is more considerable than all the rest, because of its singular use for _Essays_ upon the _Coppell_, seeing thatthere is not any other _Mettal_ mixed with it. 'Tis found in the _UpperPalatinate_, at a place called _Freyung_, and there are two sorts of it, whereof one is a kind of Crystalline Stone, and almost all good Lead; theother not so rich, and more farinaceous. By the information, coming alongwith it, they are fetcht, not from under the ground, but, the Mines of thatplace having lain long neglected, by reason of the Wars of _Germany_ andthe increase of Waters, the people, living {11} there-about take it fromwhat these Forefathers had thrown away, and had lain long in the open Air. The use above mentioned being considerable, the person, who sent it, hathbeen intreated, to inform what quantities may be had of it, if there shouldbe occasion to send for some. * * * * * _Of an Hungarian Bolus, of the same Effect with the Bolus Armenus. _ The same person gave notice also, that, besides the _Bolus Armenus_, andthe _Terra Silesiaca_, there is an Earth to be found in _Hungary_ about theRiver _Tockay_, thence called _Bolus Tockaviensis_, having as good effectsin _Physick_, as either of the former two, and commended by experience inthose parts, as much as it is by _Sennertus_ out of _Crato_, for itsgoodness. * * * * * _Of the New _American_ Whale-fishing about the Bermudas. _ Here follows a Relation, somewhat more divertising, than the precedentAccounts, which is about the new _Whale fishing_ in the _West-Indies_ aboutthe _Bermudas_, as it was delivered by an understanding and hardy Sea-man, who affirmed he had been at the killing work himself. His account, as faras remembred, was this; that though hitherto all Attempts of mastering theWhales of those Seas had been unsuccesful, by reason of the extraordinaryfierceness and swiftness of these monstrous Animals; yet the enterprisebeing lately renewed, and such persons chosen and sent thither for thework, as were resolved not to be baffled by a Sea-monster, they did prosperso far in this undertaking, that, having been out at Sea, near the saidIsle of _Bermudas_, seventeen times, and fastned their Weapons a dozentimes, they killed in these expeditions 2 old Female-Whales, and 3 Cubs, whereof one of the old ones, from the head to the extremity of the Tayl, was 88. Foot in length, by measure; its Tayl being 23. Foot broad, theswimming Finn 26. Foot long, and the Gills three Foot long: having greatbends underneath from the Nose to the Navil; upon her after-part, a Finn onthe back; being within {12} paved (this was the plain Sea-man's phrase)with fat, like the Cawl of a Hog. The other old one, he said, was some 60. Foot long. Of the Cubs, one was33. The other two, much about 25 or 26. Foot long. The shape of the Fish, he said, was very sharp behind, like the ridge of ahouse; the head pretty bluff, and full of bumps on both sides; the backperfectly black, and the belly white. Their celerity and force he affirmed to be wonderful, insomuch that one ofthose Creatures, which he struck himself, towed the boat wherein he was, after him, for the space of six or seven Leagues, in ¾ of an hours time. Being wounded, he saith, they make a hideous roaring, at which, all of thatkind that are within hearing, come towards that place, where the Animal is, yet without striking, or doing any harm to the wary. He added, that they struck one of a prodigious bigness, and by guess ofabove 100 foot long. He is of opinion, that this Fish comes nearest to thatsort of Whales, which they call the _Jubartes_; they are without teeth, andlonger than the _Greenland_-Whales, but not so thick. He said further, that they fed much upon Grass, growing at the bottom ofthe Sea; which, he affirmed, was seen by cutting up the great Bag of Maw, wherein he had found in one of them about two or three Hogsheads of agreenish grassy matter. As to the quantity and nature of the Oyl which they yield, he thought, thatthe largest sort of these Whales might afford seven or eight Tuns if wellhusbanded, although they had lost much this first time, for want of a goodCooper; having brought home but eleven Tuns. The Cubbs, by his relation, doyield but little, and that is but a kind of a Jelly. That which the oldones render, doth candy like Porks Grease, yet burneth very well. Heobserved, that the Oyl of the Blubber is as clear and fair as any Whey: butthat which is boyled out of the Lean, interlarded, becomes as hard asTallow, spattering in the burning and that which is made of the Cawl, resembleth Hoggs grease. One, but scarce credible, quality of this Oyl, he affirms to be, thatthough it be boiling, yet one may run ones hand into it without scalding;to which he adds, that it hath a very healing {13} Vertue for cuttings, lameness, &c. , the part affected being anointed therewith. One thing morehe related, not to be omitted, which is, that having told, that the time ofcatching these Fishes was from the beginning of _March_, to the end of_May_, after which time they appeared no more in that part of the Sea: hedid, when asked, whither they then retired, give this Answer, That it wasthought, they went into the Weed-beds of the Gulf of _Florida_, it havingbeen observed, that upon their Fins and Tails they have store of Clams orBarnacles, upon which, he said, Rock-weed or Sea-tangle did grow a handlong; many of them having been taken of them, of the bigness of greatOyster-shels, and hung upon the Governour of _Bermudas_ his Pales. * * * * * _A Narrative concerning the success of Pendulum-Watches at Sea for theLongitudes. _ The Relation lately made by Major _Holmes_, concerning the success of the_Pendulum-Watches_ at Sea (two whereof were committed to his Care andObservation in his last voyage to _Guiny_ by some of our Eminent_Virtuosi_, and Grand Promoters of Navigation) is as followeth; The said _Major_ having left that Coast, and being come to the Isle of St. _Thomas_ under the _Line_ accompanied with four Vessels, having thereadjusted his Watches, put to Sea, and sailed Westward, seven or eighthundred Leagues, without changing his course; after which, finding the Windfavourable, he steered towards the Coast of _Africk_, North-North-East. Buthaving sailed upon that _Line_ a matter of two or three hundred Leagues, the Masters of the other Ships, under his Conduct, apprehending that theyshould want Water, before they could reach that Coast, did propose to himto steer their Course to the _Barbadoes_, to supply themselves with Waterthere. Whereupon the said Major, having called the Master and Pilotstogether, and caused them to produce their Journals and Calculations, itwas found, that those Pilots did differ in their reckonings from that ofthe Major, one of them eighty Leagues, another about an hundred, and thethird, more; but the Major judging by his _Pendulum-Watches_, that theywere only some thirty Leagues distant from {14} the Isle of _Fuego_, whichis one of the Isles of _Cape Verde_, and that they might reach it next day, and having a great confidence in the said Watches, resolved to steer theirCourse thither, and having given order so to do, they got the very next dayabout Noon a sight of the said Isle of _Fuego_, finding themselves to saildirectly upon it, and so arrived at it that Afternoon, as he had said. These Watches having been first Invented by the Excellent Monsieur_Christian Hugens_ of _Zulichem_, and fitted to go at Sea, by the RightHonourable, the Earl of _Kincardin_, both Fellows of the _Royal Society_, are now brought by a New addition to a wonderful perfection. The saidMonsieur _Hugens_, having been informed of the success of the Experiment, made by _Major Holmes_, wrought to a friend at _Paris_ a Letter to thiseffect; Major _Holmes_ at his return, hath made a relation concerning theusefulness of _Pendulums_, which surpasseth my expectation: I did notimagine that the Watches of this first Structure would succeed so well, andI had reserved my main hopes for the New ones. But seeing that those havealready served so succesfully, and that the other are yet more just andexact, I have the more reason to believe, that the Invention of_Longitudes_ will come to its perfection. In the mean time I shall tellyou, that the _States_ did receive my Proposition, when I desired of them aPatent for these new Watches, and the recompense set a-part for theinvention in case of success; and that without any difficulty they havegranted my request, commanding me to bring one of these Watches into theirAssembly, to explicate unto them the Invention, and the application thereofto the _Longitudes_; which I have done to their contentment. I have thisweek published, that the said Watches shall be exposed to sale, togetherwith an Information necessary to use them at Sea: and thus I have brokenthe Ice. The same Objection, that hath been made in your parts against theexactness of these _Pendulums_, hath also been made here; to wit, thatthough they should agree together, they might fail both of them, by reasonthat the Air at one time might be thicker, than at another. But I haveanswered, that this difference, if there be any, will not be at allperceived in the _Penduls_, seeing that the continuall Observations, madein Winter from day to day, until Summer, have shewed me that {15} they havealwaies agreed with the Sun. As to the Printing of the _Figure_ of my NewWatch, I shall defer that yet a while: but it shall in time appear with allthe Demonstrations thereof, together with a _Treatise_ of _Pendulums_, written by me some daies since, which is of a very subtile Speculation. * * * * * _The Character, lately published beyond the Seas, of an Eminent person, notlong since dead at _Tholouse_, where he was a Councellor of Parliament. _ It is the deservedly famous _Mounsieur de Fermat_, who was, (saith theAuthor of the Letter) one of the most Excellent Men of this Age, a _Genius_so universal, and of so vast an extent, that if very knowing and learnedMen had not given testimony of his extraordinary merit, what with truth canbe said of him, would hardly be believed. He entertained a constantcorrespondence with many of the most Illustrious Mathematicians of_Europe_, and did excel in all the parts of Mathematical Science: aTestimony whereof he hath left behind him in the following Books. A Method for the Quadrature of _Parabola's_ of all degrees. A Book _De Maximis & Minimis_, which serveth not only for the determinationof Problems of _Plains_ and _Solids_, but also for the invention of_Tangents_ and _Curve Lines_, and of the _Centres_ of Gravity in Solids;and likewise for Numerical Questions. An Introduction to the Doctrine of _Plains_ and _Solids_, which is an_Analytical_ Treatise, concerning the solution of _Plains_ and _Solids_, which has been seen (as the Advertiser affirms) before Monsieur _DesCartes_ had publish'd any thing upon this Subject. A Treatise _De Contactibus Sphæricis_, where he hath demonstrated in_Solids_, what Mr. _Viet_, Master of Requests, had but demonstrated in_Plains_. Another Treatise, wherein he establisheth and demonstrateth the two Booksof _Apollonius Pergæus_, of _Plains_. And a General Method for the dimension of _Curve Lines_, &c. Besides, having a perfect knowledge in Antiquity, he was consulted from all partsupon the difficulties that did emerg therein: he hath explained abundanceof obscure places, that are {16} found in the Antients. There have beenlately printed some of his Observations upon _Athenæus_; and he that hathinterpreted _Benedetto Castelli_, of the Measure of running waters, haththence inserted in his Work a very handsome one upon an Epistle of_Synesius_, which was so difficult, that the Jesuit _Petavius_, who hathcommented upon this Author, acknowledges, that he could not understand it. He hath also made many Observations upon _Theon of Smyrne_, and upon otherAntient Authors: but most part of them are not found but scattered in hisEpistles, because he did not write much upon these kinds of Subjects, butto satisfie the curiosity of his friends. All these Mathematical Works, and all these curious searches in Antiquity, did not hinder this great _Virtuoso_ from discharging the duties of hisplace with much assiduity, and with so much ability, that he hath had thereputation of one of the greatest _Civilians_ of his Age. But that, which is most of all surprizing to many, is, that with all thatstrength of understanding, which was requisite to make good these rarequalities, lately mentioned, he had so polite and delicate parts, that hecomposed _Latin_, _French_, and _Spanish_ Verses with the same elegancy, asif he had lived in the time of _Augustus_, and passed the greatest part ofhis life at the Courts of _France_ and _Spain_. More particulars will perhaps be mention'd of the Works of this Rareperson, when all things, that he hath publish'd, shall be recovered, andwhen liberty shall be obtained of his Worthy Son, to impart unto the Worldthe rest of his Writings, hitherto unpublished. * * * * * _LONDON, _ Printed with Licence, By _John Martyn_, and _James Allestry_, Printers tothe _Royal-Society_. {17} * * * * * _Num. _ 2. PHILOSOPHICAL_TRANSACTIONS. _ * * * * * _Munday_, _April_ 3. 1665. * * * * * The Contents. _Extract of a Letter written from _Rome_, concerning the late _Comet_, and a _New_ one. Extract of another Letter from _Paris_, containing some Reflections on the precedent _Roman_ Letter. An Observation concerning some particulars, further considerable in the _Monster_, that was Mention'd in the first Papers of these _Philosophical Transactions_. Extract of a Letter written from _Venice_, concerning the Mines of _Mercury_ in Friuly. Some Observations, made in the ordering of _Silk-worms_. An Account of Mr. _Hooks Micrographia_, or the Physiological descriptions of _Minute Bodies_, made by _Magnifying Glasses_. _ * * * * * _Extract of a Letter, lately written from _Rome_, touching the late Comet, and a New one. _ I Cannot enough wonder at the strange agreement of the thoughts of thatacute French Gentleman, Monsieur _Auzout_, in the _Hypothesis_ of theComets motion, with mine; and particularly, at that of the _Tables_. I havewith the same method, whereby I find the motion of this Comet, easily foundthe Principle of that Author's _Ephemerides_, which he then thought not fitto declare; and 'tis this, that this Comet moves about the _Great Dog_, inso great a Circle, that that portion, which is {18} described, is exceedingsmall in respect of the whole circumference thereof, and hardlydistinguishable by us from a streight line. Concerning the New Comet you mention, I saw it on the 11. Of _February_, about the 24. Deg. Of _Aries_, with a Northern latitude of 24. Deg. 40. Min. The cloudy weather hath not yet permitted me to see it in _Andromeda_, as others affirm to have done. * * * * * _Extract of a Letter, written from _Paris_, containing some Reflections onpart of the precedent _Roman_ Letter. _ As to the _Hypothesis_ of _Georg. Domenico Cassini_, touching the motion ofthe _Comet_ about the _Great Dog_ in a Circle, whose Centre is in astreight line drawn from the Earth through the said Star, I believe it willshortly be publish'd in print, as a thought I lighted upon in discoursingwith one of my Friends, who did maintain, that it turned about a Centre, because that its _Perigee_ had been over against the _Great Dog_, as I hadnoted in my _Ephemerides_. This particular I did long since declare to manyof my acquaintance, whereof some or other will certainly do me that right, as to let the world know it by the Press. I have added an Observation, which I find not, that Signior _Cassini_ hath made, _viz. _ that there wasground to think, that the _Comet_ of 1652. Was the same with the present, seeing that besides the parity of the swiftness of its motion, the_Perigee_ thereof was also over against the _Great Dog_, if theObservations extant thereof, deceive not. But, to make it out, what groundI had for these thoughts, I said, that if they were true, the Comet mustneeds acomplish its revolution from 10. To 12. Years, or thereabout. But, seeing it appears not by History, that a Comet hath been seen at thosedeterminate distances of time, nor that over against the _Perigee_ of allthe other Comets, whereof particular observations are recorded, are alwaiesfound Stars of the first Magnitude, or such others, as are very notable, besides other reasons, that might be alledged, I shall not pursue thisspeculation; but rather {19} suggest what I have taken notice of in myreflexions upon former Comets, which is, that more of them enter inter ourSysteme by the sign of _Libra_ and about _Spica virginis_, than by all theother parts of the Heavens. For, both the present Comet, and many othersregistred in History, have entred that way, and consequently passed out ofit by the sign _Aries_, by which also many have entred. I did found my _Hypothesis_ upon three Observations only, _viz. _ those ofthe 22, 26, and 31. Of _December_. Nor have I done, as some have fancied ofme, who having been able to observe the Comet, the 27, 28, 29, 30, and 31. Of _December_, and to see the diminution of its motion, have judged, that Ihad only determined that diminution for the time to come, conform to theaugmentation thereof in time passed until the 29. Of _December_. For_January_ 1. (on which day I composed my _Ephemerides_) I knew not (nor anyperson here) that the motion of the Comet did diminish; but on thecontrary, most men believed, it was not the same Comet. But Signior_Cassini_ knows very well, that that was not necessary, seeing that twoportions of a _Tangent_ being given, and the _Angles_ answering thereunto, 'tis easie to find the position and magnitude of its Circle. The reason, which I think the true one, of the diminution of its Motion in Longitude, and of its Retrogradation, by me conjectured in my _Ephemerides_, I beganto be assured of, _Febr. _ 10. For until the sixth, the Comet had alwaiesadvanced, as Signior _Cassini_ also hath very well noted: but after thatday, I found that it returned in augmenting alwaies its Latitude. And Ihave constantly observed it, until _March_ 8. Between many Stars, whichmust be the same with these mentioned by _Cassini_, whereof the number wasso great, that I think, I saw of them _March_ 6. With one _Aperture_ of myGlass, more than 40. Or 50. And especially, above the head of _Aries_; butI did not particularly note the scituation of more than 12. Or 15; amongstwhich I have observed the position of the Comet since _January_ 28. Everyday, when the weather did permit, _viz. _ _January_ 29. _February_ 3, 6, 10, 17, 19, 24, 26, 27. And _March_ 6, {20} 7, 8. I left it on _March_ 8. Atthe 18. Of the Horn of _Aries_, almost in the same latitude: and I am aptto believe, it will be Eclipsed, which I wish I may be able to observe thisevening, if it be not already passed. If Signior _Cassini_ hath observed it on those daies that I have, he willbe glad to find the conformity of our Observations. I shall only add, thaton _February_ 3. We were surprized, to see the Comet again much brighterthan ordinary, and with a considerable Train. Some did believe, that itapproach'd again to us. But having beheld it with a _Telescope_, I soonsaid, that it was joyned with two small Stars, whereof one was prettybright, which I had already seen, on _February_ 28. And 29. And thisconjunction gave the _Comet_ that brightness, as it happens to most of theStars of the fifth and sixth magnitude, where 2. Or 3. Or more areconjoyned, which perhaps would shew but faintly single, though by reason oftheir proximity to one another, they appear but one Star. Hence it was, that I assured my friends here, that the following daies we should no moresee it so bright, because I knew, that there were none such small brightStars in the way, which by my former observations I conjectured it was tomove. * * * * * _An Observation imparted to the Noble Mr. _Boyle_, by Mr. _David Thomas_, touching some particulars further considerable in the Monster mentioned inthe first Papers of these _Philosophical Transactions_. _ Upon the strictest inquiry, I find by one, that saw the Monstrous Calf andstone, within four hours after it was cut out of the Cows belly, that theBreast of the Calf was not stony (as I wrote) but that the skin of theBreast and between the Legs and of the Neck (which parts lay on the smallerend of the stone) was very much thicker, than on any other part, and thatthe Feet of the Calf were so parted as to be like the Claws of a Dog. Thestone I have since seen; it is bigger at one end {21} than the other; of noplain _Superficies_, but full of little cavities. The stone, when broken, is full of small peble stones of an Ovall figure: its colour is gray likefree-stone, but intermixt with veins of yellow and black. A part of it Ihave begg'd of Dr. _Haughten_ for you, which I have sent to _Oxford_, whither a more exact account will be conveyed by the same person. * * * * * _Extract of a Letter, lately written from _Venice_ by the Learned Doctor_Walter Pope_, to the Reverend Dean of _Rippon_, Doctor _John Wilkins_, concerning the Mines of Mercury in _Friuli_; and a way of producing _Wind_by the fall of _Water_. _ The mines of _Mercury_ in _Friuli_, a Territory belonging to the_Venetians_, are about a days Journey and a half distant from _Goritia_Northwards, at a place call'd _Idria_, scituated in a Valley of the _JulianAlps_. They have been, as I am inform'd, these 160. Years in the possessionof the Emperor, and all the Inhabitants speak the _Sclavonian_ Tongue. Ingoing thither, we travell'd several hours in the best Wood I ever sawbefore or since, being very full of _Firrs_, _Oakes_, and _Beeches_, of anextraordinary thickness, straitness, and height. The Town is built, asusually Towns in the _Alps_ are, all of wood, the Church only excepted, andanother House wherein the Overseer liveth. When I was there, in _August_last, the Valley, and the Mountains too, out of which the _Mercury_ wasdug, were of as pleasant a verdure, as if it had been in the midst ofSpring, which they there attribute to the moistness of the _Mercury_; howtruly, I dispute not. That Mine, which we went into, the best and greatestof them all, was dedicated to Saint _Barbara_, as the other Mines are toother Saints, the depth of it was 125. Paces, every pace of that Countrybeing, as they inform'd us, more than 5 of our Feet. There are two waysdown to it; the shortest perpendicular way is that, whereby they bring upthe Mineral in great Buckets, and {22} by which oftentimes some of theworkmen come up and down. The other, which is the usual way, is at thebeginning not difficult, the descent not being much; the greatest troubleis, that in several places you cannot stand upright: but this holds notlong, before you come to descend in earnest by perpendicular Ladders, wherethe weight of on's body is found very sensible. At the end of each Ladder, there are boards a-cross, where we may breath a little. The Ladders, as wesaid, are perpendicular, but being imagined produced, do not make oneLadder, but several parallel ones. Being at the bottom, we saw no more thanwe saw before, only the place, whence the Mineral came. All the way down, and the bottom, where there are several lanes cut out in the Mountain, islined and propt with great pieces of Firr-trees, as thick as they can beset. They dig the Mineral with Pick-axes, following the veins: 'tis for themost part hard as a stone, but more weighty; of a Liver-colour, or that of_Crocus Metallorum_. I hope shortly to shew you some of it. There is alsosome soft Earth, in which you plainly see the _Mercury_ in littleparticles. Besides this, there are oftentimes found in the Mines roundstones like Flints, of several bignesses, very like those Globes of Hair, which I have often seen in _England_, taken out of Oxes bellies. There arealso several _Marcasites_ and stones, which seem to have specks of Gold inthem, but upon tryal they say, they find none in them. These round stonesare some of them very ponderous, and well impregnated with _Mercury_;others light, having little or none in them. The manner of getting the_Mercury_ is this: They take of the Earth, brought up in Buckets, and putit into a Sive, whose bottom is made of wires at so great a distance, thatyou may put your finger betwixt them: 'tis carried to a stream of runningwater, and wash'd as long as any thing will pass through the Sive. ThatEarth which passeth not, is laid aside upon another heap: that whichpasseth, reserved in the hole, G. In Fig. 1. And taken up again by thesecond Man, and so on, to about ten or twelve sives proportionably less. Itoften happens in the first hole, where the second Man takes up his {23}Earth, that there is _Mercury_ at the bottom; but towards the farther end, where the Intervals of the wires are less, 'tis found in very greatproportion. The Earth laid aside is pounded, and the same operationrepeated. The fine small Earth, that remains after this, and out of whichthey can wash no more _Mercury_, is put into Iron retorts and stopt, because it should not fall into the Receivers, to which they are luted. Thefire forces the _Mercury_ into the Receivers: the Officer unluted severalof them to shew us; I observed in all of them, that he first poured outperfect _Mercury_, and after that came a black dust, which being wettedwith water discover'd it self to be _Mercury_, as the other was. They takethe _Caput mortuum_ and pound it, and renew the operation as long as theycan get any _Mercury_ out of it. This is the way of producing the _Mercury_, they call _Ordinary_, whichexceeds that, which is got by washing, in a very great proportion, as youwill perceive by the account annext. All the _Mercury_ got without the useof Fire, whether by washing, or found in the Mines (for in the digging, some little particles get together, so that in some places you might takeup two or three spoonfuls of pure _Mercury_) is call'd by them _VirginMercury_, and esteem'd above the rest. I inquir'd of the Officer whatvertue that had more, than the other; he told me that making an _Amalgama_of Gold and _Virgin Mercury_, and putting it to the fire, that _Mercury_would carry away all the Gold with it, which common _Mercury_ would not do. The Engins, employed in these Mines, are admirable; the Wheels, thegreatest that ever I saw in my life; one would think as great as the matterwould bear: all moved by the dead force of the water, brought thither in nochargeable Aqueduct from a Mountain, 3 Miles distant: the water pumpt fromthe bottom of the Mine by 52 pumps, 26 on a side, is contrived to moveother wheels, for several other purposes. The Labourers work for a _Julio_ a day, which is not above 6 or 7 pence, and indure not long; for, although none stay {24} underground above 6hours; all of them in time (some later, some sooner) become _paralitick_, and dye _hectick_. We saw there a man, who had not been in the Mines for above half a yearbefore, so full of _Mercury_, that putting a piece of _Brass_ in his mouth, or rubbing it in his fingers, it immediately became white like Silver: Imean he did the same effect, as if he had rubb'd _Mercury_ upon it, and soparalitick, that he could not with both his hands carry a Glass, half fullof Wine, to his mouth without spilling it, though he loved it too well tothrow it away. I have been since informed, that here in _Venice_, those that work on theback-side of Looking-glasses, are also very subject to the _Palsey_. I didnot observe, that they had black Teeth; it may be therefore, that we accuse_Mercury_ injustly for spoiling the Teeth, when given in _Venereal_diseases. I confess, I did not think of it upon the place; but, black Teethbeing so very rare in this Country, I think I could not but have markt it, had all theirs been so. They use exceeding great quantity of Wood, in making and repairing theEngins, and in the Furnaces (whereof there are 16. Each of them carrying24. Retorts;) but principally in the Mines, which need continualreparation, the Fir-trees lasting but a small time under ground. Theyconvey their Wood thus: About four miles from the Mines, on the sides oftwo mountains, they cut down the Trees, and draw them into the interjacentValley, higher in the same Valley, so that the Trees, according to thedescent of the water lye betwixt it and _Idria_: with vast charges andquantities of Wood they made a Lock or Dam, that suffers not any water topass; they expect afterwards till there be water enough to float theseTrees to _Idria_; for, if there be not a spring, (as generally there is, )Rain, or the melting of the Snow, in a short time, afford so much water, asis ready to run over the Dam, and which (the Flood-gates being open'd)carries all the Trees impetuously to _Idria_, where the Bridge is builtvery strong, and at very oblique Angles to the stream, on purpose to stopthem, and throw them on shore neer the Mines. {25} Those Mines cost the _Emperour_ heretofore 70000. Or 80000. _Florens_yearly, and yielded less _Mercury_ than at present, although it costs himbut 28000. _Florens_ now. You may see what his Imperial Majesty gets by thefollowing account, of what _Mercury_ the Mines of _Idria_ have producedthese last three years. 1661. L. Ordinary _Mercury_ 198481 Virgin _Mercury_ 6194 -------- 204675 -------- 1662. L. Ordinary _Mercury_ 225066 Virgin _Mercury_ 9612 -------- 234678 -------- 1663. L. Ordinary _Mercury_ 244119 Virgin _Mercury_ 11862 -------- 255981 -------- There are alwaies at work 280 persons, according to the relation I receivedfrom a very civil person, who informed me also of all the other particularsabove mentioned, whose name is _Achatio Kappenjagger_; his Office, _Contra-scrivano per sua Maestà Cesarea in Idria del Mercurio_. To give some light to this Narrative, take this Diagramme: F. Is the water, C. B. A vessel, into which it runs. DG. EH. FI. Are streams perpetuallyissuing from that vessel; D. E. F. Three sives, the distance of whose wiresat bottom lessen proportionably. G. The place, wherein the Earth, thatpass'd through the sive D. Is retained; from whence 'tis taken by thesecond man; and what passes through the sive E. Is retained in H. And so ofthe rest. K. L. M. Wast water, which is so much impregnated with _Mercury_, that it cureth Itches and sordid Ulcers. See Fig. 1. [Illustration] I will trespass a little more upon you, in describing the contrivance ofblowing the Fire in the _Brassworks_ of _Tivoli_ neer _Rome_ (it being newto me) where the Water blows the Fire, not by moving the Bellows, (which iscommon) but by affording the Wind. See Fig. II. Where A. Is the {26} River, B. The Fall of it, C. The Tub into which it falls, LG. A Pipe, G. Theorifice of the Pipe, or Nose of the Bellows, GK. The Hearth, E. A hole inthe Pipe, F. A stopper to that hole, D. A place under ground, by which thewater runs away. Stopping the hole E, there is a perpetual strong wind, issuing forth at G: and G. Being stopt, the wind comes out so vehemently atE, that it will, I believe, make a Ball play, like that at _Frescati_. [Illustration] * * * * * _An Extract of a Letter, containing some Observations, made in the orderingof _Silk-worms_, communicated by that known _Vertuoso_, Mr. _DudleyPalmer_, from the ingenuous Mr. _Edward Digges_. _ I herewith offer to your _Society_ a small parcel of my _Virginian_ Silk. What I have observed in the ordering of Silk-worms, contrary to thereceived opinion, is: 1. That I have kept leaves 24. Hours after they are gathered, and flungwater upon them to keep them from withering; yet when (without wiping theleaves) I fed the worms, I observed, they did as well as those freshgathered. 2. I never observed, that the smell of _Tobacco_, or smels that are rank, did any waies annoy the worm. 3. Our country of _Virginia_ is very much subject to Thunders: and it haththundered exceedingly when I have had worms of all sorts, some newlyhatched; some half way in their feeding; others spinning their Silk; yet Ifound none of them concern'd in the Thunder, but kept to their business, asif there had been no such thing. 4. I have made many bottoms of the Brooms (wherein hundreds of worms spun)of _Holly_; and the prickles were so far from hurting them, that even fromthose prickles they first began to make their bottoms. I did hope with this to have given you assurance, that by retarding thehatching of seed, two crops of silk or more {27} might be made in a Summer:but my servants have been remiss in what was ordered, I must crave yourpatience till next year. * * * * * _An account of _Micrographia_, or the _Physiological Descriptions_ of_Minute Bodies_, made by _Magnifying Glasses_. _ The Ingenious and knowing Author of this _Treatise_, Mr. _Robert Hook_, considering with himself, of what importance a faithful _History of Nature_is to the establishing of a solid Systeme of _Natural Philosophy_, and whatadvantage _Experimental_ and _Mechanical_ knowledge hath over thePhilosophy of _discourse_ and _disputation_, and making it, upon thataccount, his constant business to bring into that vast Treasury whatportion he can, hath lately published a Specimen of his abilities in thiskind of study, which certainly is very welcome to the Learned andInquisitive world, both for the _New discoveries_ in _Nature_, and the _NewInventions_ of _Art_. As to the _former_, the Attentive Reader of this Book will find, that therebeing hardly any thing so small, as by the help of _Microscopes_, to escapeour enquiry, a new visible world is discovered by this means, and the Earthshews quite a new thing to us, so that in every _little particle_ of itsmatter, we may now behold almost as great a variety of creatures, as wewere able before to reckon up in the whole _Universe_ it self. Here ourAuthor maketh it not improbable, but that, by these helps the subtilty ofthe composition of Bodies, the structure of their parts, the varioustexture of their matter, the instruments and manner of their inwardmotions, and all the other appearances of things, may be more fullydiscovered; whence may emerge many admirable advantages towards theenlargement of the _Active_ and _Mechanick_ part of knowledge, because wemay perhaps be enabled to discern the secret {28} workings of _Nature_, almost in the same manner, as we do those that are the productions of_Art_, and are managed by _Wheels_, and _Engines_, and _Springs_, that weredevised by Humane wit. To this end, he hath made a very curious _Survey_ ofall kinds of bodies, beginning with the _Point of a Needle_, and proceedingto the _Microscopical_ view of the _Edges_ of _Rasors, Fine Lawn, Tabby, Watered Silks, Glass-canes, Glass-drops, Fiery Sparks, Fantastical Colours, Metalline Colours, the Figures of Sand, Gravel in Urine, Diamonds inFlints, Frozen Figures, the Kettering Stone, Charcoal, Wood and otherBodies petrified, the Pores of Cork, and of other substances, Vegetablesgrowing on blighted Leaves, Blew mould and Mushromes, Sponges, and otherFibrous Bodies, Sea-weed, the Surfaces of some Leaves, the stinging pointsof a Nettle, Cowage, the Beard of a wild Oate, the seed of the Corn-violet, as also of Tyme, Poppy and Purslane. _ He continues to describe _Hair, thescales of a Soal, the sting of a Bee, Feathers_ in general, and inparticular those of _Peacocks; the feet of Flies; and other Insects; theWings and Head of a Fly; the Teeth of a Snail; the Eggs of Silk-worms; theBlue Fly; a water Insect; the Tufted Gnat; a White Moth; theShepheards-spider; the Hunting Spider, the Ant; the wandring Mite; theCrab-like insect, the Book-worm, the Flea, the Louse, Mites, Vine mites. _He concludeth with taking occasion to discourse of two or three veryconsiderable subjects, viz. _The inflexion of the Rays of Lights in theAir; the Fixt stars; the Moon. _ In representing these particulars to the Readers view, the Author hath notonly given proof of his singular skil in delineating all sorts of Bodies(he having drawn all the _Schemes_ of these 60 _Microscopical_ objects withhis own hand) and of his extraordinary care of having them so curiouslyengraven by the Masters of that Art; but he hath also suggested in theseveral reflexions, made upon these Objects, such conjectures, as arelikely to excite and quicken the Philosophical heads to very noblecontemplations. Here are found inquiries concerning the _Propagation ofLight_ through {29} differing mediums; concerning _Gravity_, concerning the_Roundness_ of Fruits, stones, and divers artificial bodies; concerning_Springiness_ and _Tenacity_; concerning the _Original_ of _Fountains_;concerning the _dissolution of Bodies into Liquors_; concerning_Filtration_, and the ascent of Juices in Vegetables, and the use of their_Pores_. Here an attempt is made of solving the strange _Phænomena_ of_Glass-drops_; experiments are alleged to prove the _Expansion_ of _Glass_by heat, and the _Contraction_ of _heated-Glass_ upon cooling; _Des Cartes_his _Hypothesis of Colours_ is examined: the _cause of Colours_, mostlikely to the Author, is explained: Reasons are produced, that _Reflection_is not necessary to produce _colours_, nor a _double refraction_: someconsiderable _Hypotheses_ are _offered_, for the explication of Light byMotion; for the producing of all colours by Refraction; for reducing allsorts of colours to two only, _Yellow_ and _Blew_; for making the _Air_, adissolvent of all _Combustible Bodies_: and for the explicating of all theregular figures of _Salt_, where he alleges many notable instances of the_Mathematicks_ of _Nature_, as having even in those things which we accountvile, rude & course, shewed abundance of curiosity and excellent _Geometry_and _Mechanism_. And here he opens a large field for inquiries, andproposeth Models for prosecuting them, 1. By making a full collection ofall the differing kinds of _Geometricall_ figur'd bodies; 2. By gettingwith them an exact History of their places where they are generated orfound: 3. By making store of Tryals in Dissolutions and Coagulations ofseveral Crystallizing Salts: 4. By making trials on metalls, Minerals andStones, by dissolving them in severall _Menstruums_, and Crystallizingthem, to see what Figures will arise from those several compositums: 5. Bycompounding & coagulating several Salts together into the same mass, toobserve the Figure of that product: 6. By inquiring the closenes or rarityof the texture of those bodys by examining their gravity, and theirrefraction, &c. 7. By examining what operations the fire hath upon severalkinds of Salts, what changes it causes in their figures, Textures, or {30}Vertues. 8. By examining their manner of dissolution, or acting upon thosebodies dissoluble in them and the Texture of those bodies before and afterthe process. 9. By considering, by what and how many means, such and suchfigures, actions and effects could be produced, and which of them might bethe most likely, &c. He goes on to offer his thoughts about the Pores of bodies, and a _kind_ of_Valves_ in wood; about spontaneous generation arising from thePutrefaction of bodies; about the nature of the Vegetation of mold, mushromes, moss, spunges; to the last of which he scarce finds any Bodylike it in texture. He adds, from the naturall contrivance, that is foundin the leaf of a Nettle, how the stinging pain is created, and thence takesoccasion to discourse of the poysoning of Darts. He subjoyns a curiousdescription of the shape, _Mechanism_ and use of the _sting_ of a _Bee_;and shews the admirable Providence of Nature in the contrivance and fabrickof _Feathers_ for Flying. He delivers those particulars about the Figure, parts and use of the head, feet, and wings of a Fly, that are not common. He observes the various wayes of the generations of Insects, and discourseshandsomely of the means, by which they seem to act so prudently. He takethnotice of the _Mechanical_ reason of the _Spider's_ Fabrick, and makethpretty Observations on the hunting Spider, and other Spiders and theirWebs. And what he notes of a Flea, Louse, Mites, and Vinegar-worms, cannotbut exceedingly please the curious Reader. Having dispatched these Matters, the Author offers his Thoughts for theexplicating of many _Phænomena_ of the Air, from the _Inflexion_, or from a_Multiplicate Refraction_ of the rays of Light within the Body of the_Atmosphere_, and not from a _Refraction_ caused by any terminating_superficies_ of the Air above, nor from any such exactly defin'd_superficies_ within the body of the _Atmosphere_; which conclusion hegrounds upon this, that a _medium_, whose parts are unequally _dense_, andmov'd by various motions and transpositions as to one another, will produceall these {31} visible effects upon the rays of Light, without any other_coefficient_ cause: and then, that there is in the Air or _Atmosphere, such_ a variety in the constituent parts of it, both as to their _density_and _rarity_, and as to their divers mutations and positions one toanother. He concludeth with two _Celestial Observations_; whereof the _one_ imports, what multitudes of Stars are discoverable by the _Telescope_, and thevariety of their magnitudes; intimating with all, that the longer theGlasses are, and the bigger apertures they will indure, the more fit theyare for these discoveries: the _other_ affords a description of a _Vale_ inthe _Moon_, compared with that of _Hevelius_ and _Ricciolo_; where theReader will find several curious and pleasant Annotations, about the Pitsof the _Moon_, and the Hills and Coverings of the same; as also about thevariations in the _Moon_, and its _gravitating_ principle, together withthe use, that may be made of this Instance of a gravity in the _Moon_. As to the _Inventions of Art_, described in this Book, the curious Readerwill there find these following: 1. A _Baroscope_, or an Instrument to shew all the Minute Variations in the_Pressure of the Air_; by which he affirms, that he finds, that before andduring the time of rainy weather, the Pressure of the Air is less; and indry weather, but especially when an _Easterly_ Wind (which having past overvast Tracts of Land, is heavy with earthy particles) blows, it is muchmore, though these changes be varied according to very odd Laws. 2. A _Hygroscope_, or an Instrument, whereby the _Watery steams_, volatilein the Air, are discerned, which the Nose it self is not able to find. Which is by him fully described in the Observation touching the _Beard of awild Oate_, by the means whereof this Instrument is contrived. 3. An Instrument for _graduating Thermometers_, to make them _Standards_ of_Heat_ and _Cold_. 4. A _New Engine_ for _Grinding Optick Glasses_, by means of which hehopes, that any Spherical Glasses, of what length {32} soever, may bespeedily made: which seems to him most easie, because, if it succeeds, withone and the same Tool may be ground an _Object Glass_ of any length orbreadth requisite, and that with very little or no trouble in fitting the_Engine_, and without much skill in the _Grinder_. He thinks it very exact, because to the very last stroke the Glass does regulate and rectifie the_Tool_ to its exact Figure; and the longer or more the _Tool_ and _Glass_are wrought together, the more exact will both of them be of the desiredFigure. He affirms further, that the motions of the Glass and Tool do socross each other, that there is not one point of eithers surface, but haththousands of cross motions thwarting it, so that there can be no kind of_Rings_ or _Gutters_ made, either in the _Tool_ or _Glass_. 5. A _New Instrument_, by which the _Refraction_ of all kinds of Liquorsmay be exactly measured, thereby to give the Curious an opportunity ofmaking Trials of that kind, to establish the _Laws_ of _Refraction_, towit, whether the _Sines of the Angles of Refraction are respectivelyproportionable to the Sines of the Angles of Incidence:_ This Instrumentbeing very proper to examine very accurately, and with little trouble, andin small quantities, the _Refraction_ of any Liquor, not only for _one_inclination, but for _all_; whereby he is enabled to make accurate_Tables_. By the same also he affirms to have found it true, that what_proportion_ the _Sine_ of the Angle of the one _inclination_ has to the_Sine_ of its Angle of _Refraction_, correspondent to it, the sameproportion have all the other _Sines_ of Inclination to their respective_Sines_ of _Refractions_. Lastly, this Author despairs not that there may be found many MechanicalInventions, to improve our Senses of _Hearing, Smelling, Tasting, Touching_, as well as we have improved that of _Seeing_ by _OptickGlasses_. * * * * * London, Printed with Licence for _John Martyn_, and _James Allestry_, Printers to the _Royal Society_. {33} * * * * * _Numb. _ 3. PHILOSOPHICAL_TRANSACTIONS. _ * * * * * _Munday_, _May_ 8. 1665. * * * * * The Contents. _Some Observations and Experiments upon _May-dew_. The Motion of the _Second Comet_ predicted, by the same person, who predicted that of the former. A Relation of the Advice, given by a _French_ Gentleman, touching the Conjunction of the _Ocean_ and the _Mediterranean_. Of the way of killing _Ratle-snakes_, used in _Virginia_. A Relation of Persons kill'd with Subterraneous _Damps_. Of the _Mineral_ of _Liege_, yielding both _Brimstone_, and _Vitriol_, and the way of extracting them out of it, used at _Liege_. An Account of Mr. _Boyle's_ Experimental _History_ of_ Cold. * * * * * _Some Observations and Experiments upon _May-Dew_. _ That ingenious and inquisitive Gentleman, Master _Thomas Henshaw_, havinghad occasion to make use of a great quantity of _May-dew_, did, by severalcasual Essayes on that Subject, make the following Observations and Tryals, and present them to the _Royal Society_. {34} That _Dew_ newly gathered and filtred through a clean Linnen cloth, thoughit be not very clear, is of a yellowish Colour, somewhat approaching tothat of Urine. That having endevoured to putrefy it by putting several proportions intoGlass bodies with blind heads, and setting them in several heats, as ofdung, and gentle baths, he quite failed of his intention: for heat, thoughnever so gentle, did rather clarify, and preserve it sweet, thoughcontinued for two moneths together, then cause any putrefaction orseparation of parts. That exposing of it to the Sun for a whole Summer in Glasses, that holdabout two Gallons, with narrow mouths, that might be stopp'd with Cork, theonly considerable alteration, he observed to be produced in it, was, thatStore of green stuff (such as is seen in Summer in ditches and standingwaters) floated on the top, and in some places, grew to the sides of theGlass. That putting four or five Gallons of it into a half Tub, as they call it, of Wood, and straining a Canvas over it, to keep out Dust and Insects, andletting it stand in some shady room for three weeks or a month, it did ofitself putrefy and stink exceedingly, and let fall to the bottom a blacksediment like Mudd. That, coming often to see, what Alterations appeared in the putrefaction, He observed, that at the beginning, within twenty four hours, a slimy filmfloated on the top of the water, which after a while falling to the bottom, there came another such film in its place. That if _Dew_ were put into a long narrow Vessel of Glass, such as formerlywere used for Receivers in distilling of _Aqua Fortis_, the slime wouldrise to that height, that He could take it off with a Spoon; and when hehad put a pretty quantity of it into a drinking Glass, and that it hadstood all night, and the water dreined from it, if He had turned it out ofhis hand, it would stand upright in figure of the Glass, in substance likeboyled white Starch, though something more transparent, if his memory(_saith he_) fail him not. That having once gotten a pretty quantity of this gelly, and put it into aGlass body and Blind-head, He set it into a gentle {35} Bath with anintention to have putrefied it, but after a few days He found, the head hadnot been well luted on, and that some moisture exhaling, the gelly wasgrown almost dry, and a large _Mushrom_ grown out of it within the Glass. It was of a loose watrish contexture, such an one, as he had seen growingout of rotten wood. That having several Tubs with good quantity of _Dew_ in them, set toputrefy in the manner abovesaid, and comming to pour out of one of them tomake use of it, He found in the water a great bunch, bigger than his fist, of those Insects commonly called _Hog-lice_ or _Millepedes_, tangledtogether by their long tailes, one of which came out of every one of theirbodies, about the bigness of a Horsehair: The Insects did all live and moveafter they were taken out. That emptying another Tub, whereon the Sun, it seems, had used sometimes toshine, and finding, upon the straining it through a clean linnen cloth, twoor three spoonfulls of green stuff, though not so thick nor so green asthat above mentioned, found in the Glasses _purposely_ exposed to the Sun, He put this green stuff in a Glass, and tyed a paper over it, and comingsome dayes after to view it, He found the Glass almost filled with aninnumerable Company of small Flyes, almost all wings, such as are usuallyseen in great Swarms in the Aire in Summer Evenings. That setting about a Gallon of this _Dew_ (which, he saith, if hemisremember not, had been first putrefied and strained) in an openJarre-Glass with a wide mouth, and leaving it for many weeks standing in aSouth-window, on which the Sun lay very much, but the Casements were keptclose shut; after some time coming to take account of his _Dew_, He foundit very full of little Insects with great Heads and small tapering Bodies, somewhat resembling Tadpoles, but very much less. These, on his approach tothe Glass, would sink down to the bottom, as it were to hide themselves, and upon his retreat wrigle themselves up to the top of the water again. Leaving it thus for some time longer, He afterwards found the room veryfull of Gnats, though the Door and Windows were kept shut. He adds, that Hedid not at first suspect, that those Gnats had any {36} relation to the_Dew_, but after finding the Gnats to be multiplied and the little watryAnimals to be much lessened in quantity, and finding great numbers of theirempty skins floating on the face of his _Dew_, He thought, he had justreason to perswade himself, the Gnats were by a second Birth produced ofthose little Animals. That vapouring away great quantities of his putrefied _Dew_ in GlassBasons, and other Earthen glased Vessels, He did at last obtain, as heremembers, above two pound of _Grayish Earth_, which when he had washedwith more of the same _Dew_ out of all his Basons into one, and vapoured tosiccity, lay in leaves one above another, not unlike to some kind of brownPaper, but very friable. That taking this Earth out, and after he had well ground it on a Marble, and given it a smart Fire, in a coated Retort of Glass, it soon melted andbecame a Cake in the bottom, when it was cold, and looked as if it had beenSalt and Brimstone in a certain proportion melted together; but, as heremembers, was not at all inflamable. This ground again on a Marble, _hesaith_, did turn Spring water of a reddish purple Colour. That by often calcining and filtring this Earth, He did at last extractabout two ounces of a fine small _white Salt_, which, looked on through agood _Microscope_, seemed to have Sides and Angles in the same number andfigure, as _Rochpeeter_. * * * * * _The Motion of the _Second_ Comet predicted, by the same Gentleman, whopredicted that of the _former_. _ Monsieur _Auzout_, the same Person, that not long since communicated to theWorld his _Ephemerides_ touching the course of the former _Comet_, andrecommended several Copies of them to the _Royal Society_, to compare theirObservations with his Account, and thereby, either to verifie hisPredictions, or to shew, wherein they differ, hath lately sent another_Ephemerides_ concerning the Motion of the Second _Comet_, to the same end, that invited him to send the other. {37} In that Tract he observes, first in _General_, that this second _Comet_ iscontrary to the precedent, almost in all particulars: seeing that the_former_ moved very swift, _this_, pretty slow; _that_ against the Order ofthe signs from East to West, _this_, following them, from West to East:_that_, from South to North, _this_, from North to South, as far as it hathbeen hitherto, that we hear off, observed: _that_, on the side opposite tothe Sun, _this_, on the same side: _that_, having been in its _Perigee_ atthe time of its Opposition, _this_, having been there, out of the time ofits Conjunction: where he taketh also notice, that this _Comet_ differs inbrightness from the other, as well in its Body, which is far more vivid anddistinct, as in its _Train_, whose splendor is much greater, since it maybe seen even with great _Telescopes_, which were useless in the former, byreason of its dimness. After this he descends to particulars, and informsus, that he began to observe this Comet _April_ the second, and continuedfor some days following, and that as soon as he had made three or fourObservations, he resolved to try again an _Ephemerides_; but that, havingno instruments exact enough, and the Comet being in a place, destitute ofStars, and subject to Refractions, he feared to venture too much uponObservations so neer one another, since in such matters a perfect exactnessis necessary, and wished to see some precedent Observations to direct him:which having obtained, he thereby verified what he had begun, and resolvedto carry on his intended _Ephemerides_, especially being urged by hisFriends, and engaged by his former undertaking, that so it might not bethought a meer hazard, that made him hit in the former; as also, that hemight try, whether his Method would succeed as well in slower, as inswifter Comets, and in those, that are neer the Sun; as in such as areopposite thereunto, to the end, that men might be advertised of the_determination_ of its use, if it could not serve but in certain particularCases. He relateth therefore, that he had finished this New _Ephemerides_ _April_the sixth, and put it presently to the Press; in doing of which, he hopes, he hath not disobliged the Publick: seeing that, though we should loose thesight of this Star within a few days, by reason of its approach to the Sun, yet having found, {38} that it is always to rise before the Sun, and thatwe may again see it better, when it shall rise betimes, towards the end of_May_, and in the beginning of _June_, if the cleerness of the Day-breakhinder us not; he thought it worth the while to try, whether the truth ofthis _Ephemerides_ could be proved. He affirms then, that the _Line_ described by this Star resembles hithertoa _Great Circle_, as it is found in all other Comets in the midst of theirCourse. He finds the said Circle inclined to the _Ecliptick_ about 26. D. 30'. And the _Nodes_, where it cuts it, towards the beginning of _Gemini_and _Sagittary_; that it declines from the _Equator_ about 26. _d_ and cutsit towards the 11. D. And consequently, that its greatest _Latitude_ hathbeen towards _Pisces_, where it must have been _March_ 24. And its greatest_Declination_, towards the 25 d. Of the _Equator_, where it was to havebeen _April_ 11. He puts it in its _Perigee_ _March_ 27. About three of the Clock in theAfternoon, when it was about the 15 degrees of _Pisces_, a little more_Westerly_ then _Marshab_, or the _Wing_ of _Pegasus_, and that it was tobe in _Conjunction_ with the _Sun_, _April_ 9. Where yet he noteth, thataccording to another Calculation, the _Perigee_ was _March_ 27. Moretowards Night, so that the Comet advances a little more towards the _East_, and retards towards the _West_; which not being very sensible in the firstdays, differs more about the end, and in the beginning; which he leaves toObservation. He calculateth, that the greatest Motion it could make in one day, hathbeen 4. D. And 8'. Or 9'; in one hour, about 10'. And 25". So that its_Diurnal Motion_ is to its last distance from the Earth a little more thanas 1. To 14. And its _Hourly Motion_, as 1. To 330. He wonders, that it hath not been seen sooner; the first Observations thathe hath seen, but made by others, being of _March_ 17. Whereas he finds, that it might have been seen since _January_, at least in the Months of_February_ and _March_, when it rose at 2 of the Clock and before: becauseit is very likely, that, considering its bigness and brightness, when itwas towards its _Perigee_, it was visible, since that towards the end of_February_ it was not three times as much remote from the Earth, than whenit was in its _Perigee_, and that towards the end of _January_ it was notfive times as much. {39} In the interim, _saith he_, the other _Comet_ could be seen with the nakedeye until _January_ 31. When it was more than ten times further remote, than in its _Perigee_, although it was not by far so bright, nor itsstreamer shining as this hath appeared. He wishes, that all the changes that shall fall out in this _Comet_, mightbe exactly observ'd; because of its not being swift, and the Motion of theEarth very sensible, unless the _Comet_ be extreamly remote, we should findmuch more light from this, than the former Star, about the Grand Question, whether the _Earth_ moves or not; this Author having all along entertainedhimself with the hopes, that the Motion of _Comets_ would evince, whetherthe _Earth_ did move or not; and this very _Comet_ seemed to him to have bydesign appeared for that end, if it had had more _Latitude_, and thatconsequently we might have seen it before Day break. He wishes also, that, if possible, it may be accurately observed, whether it will not a littledecline from its great Circle towards the _South_; Judging, that someimportant truth may be thence deduced, as well as if its motion retardedmore, than the place of its _Perigee_ (which will be more exactly knownwhen all the passed Observations shall have been obtained) and its greatestMotion do require. He fears only, that it being then to rise at Break of Day, exactObservations cannot be made of it: but he would, at least have it soughtwith _Telescopes_, his _Ephemerides_ directing whereabout it is to be. _April_ 10. It was to be over against the point of the _Triangle_, and fromthence more _Southerly_ by more than two degrees; and _April_ 11. Overagainst the bright Star of _Aries_, _April_ 17. Over against the Stars ofthe _Fly_, a little more _Southerly_, and _May_ 4 it is to be over againstthe _Pleiades_, and about the fourth or fifth of the same Month, it is tobe once more in _Conjunction_ with the _Sun_; after which time, the _Sun_will move from it _Eastward_, and leave it towards the _West_; which willenable us to see it again at a better hour, provided the cleerness of theDay-break be no impediment to us. He addeth, that this Star must have beenthe third time in _Conjunction_ with the _Sun_, about the time when itfirst began to appear: and foresees, that from all these particulars manyconsiderable consequences may be deduced. {40} It will cut the _Ecliptick_ about the end of _July_, new Style, a littlemore _Eastwards_ than the _Eye_ of _Taurus_; at which time there will be noseeing of it, except it be with a _Telescope_. It will be towards the _End_ of _April_, new style, twice as far distant asit was in _Perigee_, thrice as far, _May_ the fourth, four times, _May_ theeighteenth, and five times, _June_ the first, &c. He would not have Men surprised, that there have been two _Comets_ withinso short a time; seeing, _saith he_, there were four, at least three, inthe Year 1618. And in other Years there have been two and more at the sametime. What he adds about their signification, we leave to _Astrologers_ todispute it with him. He concludeth with asking pardon, if he have committedmistakes, which he hopeth he shall obtain the sooner, because of the smalltime he hath had for these calculations; and he wishes that he could havemade all the Observations himself, seeing that it is easie to fail, whenone must trust to the Observations of others, whereof we know not theexactness: where he instanceth, that according to his Observations, the wayof the _Comet_ should go neerer the Ecliptick than he hath marked it, evenwithout having any great regard to the Refractions: but since he wouldsubject himself to others, he hath made it pass a little higher, which, hesaith, was almost insensibly so, in those few days that he was observingand writing, but that this may perhaps become sensible hereafter; which ifit be so, he affirms that it will cut the _Ecliptick_ and _Equator_ sooner, than he hath marked it, &c. However, he thinks it convenient, to have givenaforehand a common Notion of what will become of a _Comet_, to prepare menfor all the Changes that may fall out concerning it: which he affirms hehath endeavoured to do; the rest being easie to correct, as soon as anygood Observations, somewhat distant, have been obtained, considering, thatthere need but two very exact ones, a little distant when the Star is notswift, to trace its Way; although there must be at least three, to find outall the rest. But, then would he have it considered, that although hisMethod should be very exact, if there be not at hand Instruments bigenough, and Globes good enough to trust to, nothing can be done perfectlyin these kind of Predictions. {41} * * * * * _A Relation of the advice given by Monsieur _Petit_, Intendant of theFortifications of _Normandy_, touching the Conjunction of the _Ocean_ and_Mediterranean_. _ This Intelligent Gentleman, Monsieur _Petit_, having been consulted with, touching the Conjunction of the _Ocean_ and _Mediterranean_, delivers firstthe Proposition, and then giveth his thoughts upon it. The Proposition is, That there being about two Leagues below _Castres_ in_Languedoc_ a Rivolet, called _Sor_, passing to _Revel_, there may by themeans thereof be made a Communication of the two Seas, by joyning theWaters of this Rivolet by a Channel (to be kept full all the year long)with those of St. _Papoul_, and others, which fall into _Fresqueil_(another small River) that runs into the _Aude_ below _Carcassone_, and gotogether to _Narbonne_, scituated upon the _Mediterranean_. Having given the Proposition, he adds some particulars, to illustrate thesame, before he declares his judgment upon it. For he relateth, that thereis but one way, after the division of the Waters, to pass to the_Mediterranean_, which is by a Rivolet, called _Fresqueil_, that isconjoyn'd with the _Aude_: But, to pass to the _Ocean_, there are three;One, by _Riege_, entring into the _Caronne_ above _Tholouse_; the other, by_Lers_, passing on the side, and below the same Town; and the third, by_Sor_, falling into the River _Agoust_ under _Castres_, afterwards into the_Tarne_, and thence to _Montauban_, and lastly into the _Garonne_. Andthat, to compass this design, all these Rivers and Rivolets are first to bemade Navigable unto their _Sluces_; that of _Aude_ and _Fresqueil_ for the_Mediterranean_, and one of the others, such as shall be chosen, for the_Ocean_. He addeth, that, as to the several Ways passing to the _Ocean_, all of them commended as proper and convenient, and the three Countriesconcerned therein, speaking every one for their advantage: Those of_Castres_ and {42} _Montauban_, are for the River _Agoust_; those of_Tholouse_, for _Riege_; and the rest, for _Lers_. Now concerning his Opinion upon this Proposition, he thinks, that all thathath been represented touching this matter, can signifie very little, seeing that the main thing is wanting, which is the assurance, and certainand positive mensuration of the height and quantity of the Waters, necessary to fall into both the Channels of the _Aude_ and _Caronne_: thatthere must be plenty of that, to furnish at all times and alwayes thehighest and first _sluces_, since what once issues thence, doth never enteragain into them; and after some Boats are passed, if there should not be asufficient supply for those that come after; either to go up, or to godown, all would stand dry, and Merchants and their commodities would staylong enough expecting the supply of Rains, to their great detriment. Heconcludeth therefore, that no knowing and discreet Person is able, inmatters of this nature, to give a positive answer, without having beforehim a large and exact Topographical Map of those places, and of the sourcesof all the Rivolets, that are to supply the Water to the Head of thepretended Channel, together with a full account of the survey andmensuration of all the places, through which it is to pass; of the Natureof the Ground, whether it be stony, sandy, rocky, &c. Of the exact level ofall the places, where it is to be made, and of the several risings anddepressions thereof, to be assured that the Water may be conveyed to thegreatest rising, and to the highest _Sluce_; and lastly, of the quantity, that may be had at high, middle, and low Water, to have enough for alltimes; that all these things being first made out, 'tis then time enough tojudge of the possibility of the thing, and to calculate the chargesnecessary for Execution. This Artist having thus prudently waved this Proposition, diverts himselfwith reflecting upon several others of the like nature, among which heinsists chiefly upon two, whereof one is that so much celebrated in_Egypt_; the other, of _Germany_. And he is of Opinion, that the mostimportant of all is that, of conjoyning the _Red sea_ by the _Nile_ withthe _Mediterranean_, which he looks upon as the most excellent conveniencyto go into the _East Indies_ without doubling the _Cape of Good Hope_; andyet it {43} could not be executed by those great Kings of _Egypt_, thatraised so many stupendious _Pyramids_; although in his Opinion the reasonsalleged by _Historians_ to justifie them for having abandoned thatundertaking are of no validity, and that the _Red Sea_ cannot be, as theyfeared, higher than the _Nile_, and therefore not indanger the inundationof _Egypt_. The other Proposition was made to _Charles Magna_, _Anno_ 793. For joyningthe _Euxine_ Sea and the _Ocean_ together, by a Channel, which was begunfor that end, and designed to be 2000. Paces long and 100. Paces broad, betwixt the River _Altmull_, falling into the _Danube_ above _Ratisbone_, and the River _Rott_, passing at _Nurenberg_, and thence running into the_Main_, and so into the _Rhine_. But yet this also proved abortive, thoughthere was great appearance of success at first. * * * * * _Of the Way of killing _Ratle-Snakes_. _ There being not long since occasion given at a meeting of the _RoyalSociety_ to discourse of _Ratle Snakes_, that worthy and inquisitiveGentleman, Captain _Silas Taylor_, related the manner, how they were killedin _Virginia_, which he afterwards was pleased to give in writing, attestedby two credible persons in whose presence it was done; which is, asfollows. The Wild _Penny-royal_ or _Ditany_ of _Virginia_, groweth streight up aboutone foot high, with the leaves like _Penny-royal_, with little blue tuftsat the joyning of the branches to the Plant, the colour of the Leaves beinga reddish green, but the Water distilled, of the colour of Brandy, of afair Yellow: the Leaves of it bruised are very hot biting upon the Tongue:and of these, so bruised, they took some, and having tyed them in the cleftof a long stick, they held them to the Nose of the _Ratle-Snake_, who byturning and wriggling laboured as much as she could to avoid it: but shewas killed with it, in less than half an hours time, and, as was supposed, by the scent thereof; which was done _Anno_ 1657. In the Month of _July_, at which season, they repute those creatures to be in the greatest vigourfor their poison. {44} * * * * * _A Relation of Persons killed with subterraneous _Damps_. _ This Relation was likewise made to the _Royal Society_, by that Eminent_Virtuoso_ Sir _R. Moray_, who was pleased, upon their desire, to give itthem in writing; as followeth. In a Coal-pit, belonging to the Lord _Sinclair_ in _Scotland_, where theCoal is some 18 or 20 foot thick, and antiently wasted to a great depth:The Colliers, some Weeks agoe, having wrought as deep as they could, andbeing to remove into new Rooms (as they call them) did, by taking off, asthey retired, part of the Coal that was left as Pillars to support the Roofand Earth over it, so much weaken them, that within a short space, afterthey were gone out of the Pitt, the Pillars falling, the Earth above themfilled up the whole Space, where the Colliers had lately wrought, with itsruins. The Colliers being here-by out of work, some of them adventured towork upon old remains of Walls, so near the old wastes, that strikingthrough the slender partition of the Coal-wall, that seperated between themand the place, where they used to work, they quickly perceived theirErrour, and fearing to be stifled by the bad Air, that they knew, possessedthese old wastes, in regard not onely of the Damps, which such wastes dousually afford, but because there having for many years been a Fire inthose wastes, that filled them with stifling fumes and vapors, retiredimmediately and saved themselves from the eruptions of the Damp. But nextday some seven or eight of them came no sooner so farr down the staires, that led them to the place where they had been the day before, as theyintended, but upon their stepping into the place, where the Air wasinfected, they fell down dead, as if they had been shott: And there beingamongst them one, whose Wife was informed he was stifled in that place, shewent down so far without inconvenience, that seeing her Husband near her, ventured to go to him, but being choaked by the Damp, as soon as she camenear him, she fell down dead by him. {45} This Story of Sir _R. Moray_ affirmed to have received from the _Earl_ of_Weymes_, Brother in Law to the Lord _Sinclair_, as it was written to himfrom _Scotland_. * * * * * _Of the _Mineral_ of _Liege_, yeilding both _Brimstone_ and _Vitriol_, andthe way of extracting them out of it, used at _Liege_. _ The Account of this _Mineral_, and of the way of extracting both_Brimstone_ and _Vitriol_ out of it, was procured from _Liege_, by thelately mentioned Sir _Robert Moray_ and by him communicated to the _RoyalSociety_, as follows. The _Mineral_, out of which _Brimstone_ and _Vitriol_ are extracted, is oneand the same, not much unlike Lead ore, having also oft times much Leadmingled with it, which is seperated from it by picking it out of the rest. The Mines resemble our _English_ Coal Mines dugg according to the depth ofthe _Mineral_, 15, 20, or more fathoms, as the Vein leads the Workmen, orthe subterranean waters will give them leave, which in Summer so overflowthe Mines, that the upper waters, by reason of the drought, not sufficingto make the Pumps goe, the Work ceases. To make _Brimstone_, they break the Stone or Ore into small pieces, whichthey put into Crucibles made of Earth, five foot long, square andPyramid-wise. The Entry is near a foot square. These Crucibles are laidsloaping, eight undermost, and seven above them, as it were betwixt them, that the Fire may come at them all, each having its particular Furnace orOven. The _Brimstone_ being dissolved by the violence of the heat, dropsout at the small end of the Crucible, and falls into a Leaden-Trough orReceptacle, common to all the said Crucibles, through which there runs acontinual Rivolet of cold water, conveyed thither by Pipes for the coolingof the dissolved Sulphur, which is ordinarily four hours in melting. Thisdone, the Ashes are drawn out by a crooked Iron, and being put into an IronWheel barrow, are carried out of the Hutt, and {46} being laid in a heap, are covered with other exiled or drained Ashes, the better to keep themwarm; which is reiterated, as long as they make _Brimstone_. To make _Coperas_ or _Vitriol_, they take a quantity of the said Ashes, andthrowing them into a square planked pit in the Earth, some four foot deep, and eight foot square, they cover the same with ordinary water, and let itlye twenty four hours, or until an Egg will swim upon the liquor, which isa sign, that it is strong enough. When they will boyl this, they let it runthrough Pipes into the Kettles, adding to it half as much Mother-water, which is that water, that remains after boyling of the hardned _Coperas_. The Kettles are made of Lead, 4½ foot high, 6 foot long, and 3 foot broad, standing upon thick Iron Barrs or Grates. In these the Liquor is boyledwith a strong Coal-fire, twenty four hours or more, according to thestrength or weakness of the Lee or Water. When it is come to a justconsistence, the fire is taken away, and the boyled liquor suffered to coolsomewhat, and then it is tapp'd out of the said Kettles, through holesbeneath in the sides of them, and conveyed through wooden Conduits intoseveral Receptacles, three foot deep and four foot long (made and rangednot unlike our Tan-pits) where it remains fourteen or fifteen dayes, or solong till the _Coperas_ separate it self from the water, and becomes icyand hard. The remaining water is the above-mentioned Mother-water; and theelixed or drained Ashes are the Dregs, or _Caput mortuum_, which the Lee, whereof the _Vitriol_ is made, leaves behind it in the planked Pits. * * * * * _A further Account of Mr. _Boyle_'s Experimental _History_ of _Cold_. _ In the first Papers of these _Philosophical Transactions_, some promise wasmade of a _fuller_ account, to be given by the next, of the _ExperimentalHistory of Cold_, composed by the Honourable Mr. _Robert Boyle_; it beingthen supposed, that this _History_ would have been altogether printed offat the time of publishing the {47} _Second_ Papers of these _Transactions_;but the Press, employed upon this Treatise, having been retarded somewhatlonger than was ghessed, the said promise could not be performed beforethis time: wherein it now concerns the inquiring World to take notice, thatthis subject, as it hath hitherto bin almost totally neglected, so it isnow, by this Excellent Author, in such a manner handled, and improved bynear _Two hundred_ choice _Experiments_ and _Observations_, that certainlythe _Curious_ and _Intelligent_ Reader will in the perusal thereof findcause to admire both the Fertility of a Subject, seemingly so barren, andthe Author's Abilities of improving the same to so high a Degree. But to take a short view of some of the particulars of this _History_, andthereby to give occasion to _Philosophical_ men, to take this Subject moreinto their consideration, than hitherto hath been done; the IngeniousReaders will here see, 1, That not only all sorts of _Acid_ and _Alcalizate_ Salts, and Spirits, even Spirit of Wine, but also Sugar, and Sugar of Lead mixed with Snow, arecapable of freezing other Bodies, and upon what account they are so. 2, That among the Substances capable of being frozen, there are not onlyall gross sorts of Saline Bodies, but such also as are freed from theirgrosser parts, not excepting Spirit of Urine, the _Lixivium_ of Pot-ashes, nor Oyl of Tartar, _per deliquium_, it self. 3, That many very spiritous liquors, freed from their aqueous parts, cannotbe brought to freeze, neither naturally, nor artificially: And here isoccasionally mentioned a way of keeping _Moats_ unpassable in very coldCountries, recorded by _Olaus Magnus_. 4, What are the ways proper to estimate the greater or lesser Coldness ofBodies; and by what means we can measure the intensness of Cold produced byArt, beyond that, which Nature needs to employ for the freezing of Water;as also, in what proportion water of a moderate degree of Coldness will{48} be made to _shrink_ by Snow and Salt, before it begin by Congelationto _expand_ it self; and then, how to measure by the differing Weight andDensity of the same portion of Water, what change was produced in it, betwixt the hottest time of Summer, and first glaciating degree of Cold, and then the highest, which our Author could produce by _Art_: Where anInquiry is annex'd, whether the making of these kind of Tryals with thewaters of the particular Rivers and Seas, men are to sail on, may affordany useful estimate, whether or not, and how much, ships may on thosewaters be safely loaden more in Winter, than in Summer. To which is addedthe way of making exact Discoveries of the differing degrees of Coldness indiffering Regions, by such Thermometers, as are not subject to thealterations of the _Atmosphere's_ gravitation, nor to be frozen. 5. Whether, in Cold, the diffusion from Cold Bodies be made more stronglydownwards, contrary to that of Hot Bodies: Where is delivered a way offreezing Liquors without danger of breaking the Vessel, by making thembegin to freeze at the bottom, not the top. 6. Whether that Tradition be true, that if frozen Apples or Eggs be thaw'dneer the Fire, they will be thereby spoil'd, but if immersed in cold water, the Internal Cold will be drawn out, as is supposed, by the External Cold;and the frozen Bodies will be harmlesly thawed? _Item_, Whether Iron, orother Metals, Glass, Stone, Cheese, &c. Expos'd to the freezing Air, orkept in Snow, or Salt, upon the immersing them in Water will produce anyIce? _Item_, What use may be made of what happens in the different waies ofthawing Eggs and Apples, by applying the Observation to other Bodies, andeven to Men, dangerously nipp'd by excessive Cold. Where is added not onlya memorable Relation, how the whole Body of a Man was succesfully thawedand cased all over with Ice, by being handled, as frozen Eggs and Applesare; but also the Luciferousness of such Experiments, as these: andlikewise, what the effects of Cold may be, as to the Conservation orDestruction of the Textures of Bodies: and in particular, how Meat andDrink {49} may be kept good, in very Cold Countries, by keeping it underWater, without glaciation? as also, how in extreme Cold Countries, theBodies of Dead Men and other Animals may be preserved very many yearsentire and unputrified? And yet, how such Bodies, when unfrozen, willappear quite vitiated by the excessive Cold? Where it is further inquiredinto, whether some Plants, and other Medicinal things, that have specifiqueVertues, will loose them by being throughly congealed and (several wayes)thawed? And also, whether frozen and thawed Harts-horn will yield the samequantity and strength of Salt and saline Spirit, as when unfrozen? _Item_, Whether the _Electrical_ faculty of _Amber_, and the _Attractive_ or_Directive_ Virtue of _Loadstones_ will be either impaired, or any wayesaltered by intense Cold? This Head is concluded by some considerableremarks touching the operation of Cold upon Bones, Steel, Brass, Wood, Bricks. 7, What Bodies are expanded by being frozen, and how that expansion isevinced? And whether it is caused by the intrusion of Air? As also, whether, what is contained in icy bubbles, is true and Springy Air, or not. 8, What Bodies they are, that are contracted by Cold; and how thatContraction is evinced? Where 'tis inquired, whether _Chymical Oyles_ will, by Congelation, be like expressed Oyls, contracted, or, like aqueousLiquors, expanded? 9, What are the wayes of _Measuring_ the _Quantity_ of the Expansion andContraction of Liquors by Cold? And how the Author's account of this matteragrees with what Navigators into cold Climats, mention from experience, touching pieces of Ice as high as the Masts of their Ships, and yet theDepth of these pieces seems not at all answerable to what it may besupposed to be. 10, How strong the Expansion of freezing water is? Where are enumerated theseveral sorts of Vessels, which being filled {50} with water, and exposedto the cold Air, do burst; and where also the weight is expressed, thatwill be removed by the expansive force of Freezing? Whereunto an Inquiry issubjoyned, whence this prodigious force, observed in water, expanded byGlaciation, should proceed? And whether this _Phænomenon_ may be solved, either by the _Cartesian_, or _Epicurean_ Hypothesis? 11, What is the _Sphere of Activity_ of Cold, or the Space, to whoseextremities every way the Action of a cold Body is able to reach: where thedifficulty of determining these limits, together with the causes thereof, being with much circumspection mentioned, it is observed, that the _Sphereof Activity_ of Cold is exceeding narrow, not only in comparison of that ofHeat in Fire, but in comparison of, as it were, the _Atmosphere_ of manyodorous Bodies; and even in comparison of the _Sphere of Activity_ of themore vigorous Loadstones, insomuch, that the Author hath doubted, whetherthe Sense could discern a Cold Body, otherwise then by immediate Contract. Where several Experiments are delivered for the examining of this matter, together with a curious relation of the way used in _Persia_, though a veryhot Climate, to furnish their _Conservatories_ with solid pieces of Ice ofa considerable thickness: To which is added an Observation, how far inEarth and Water the Frost will pierce downwards, and upon what accounts thedeepness of the Frost may vary. After which, the care is inculcated, thatmust be had, in examining, whether Cold may be diffused through all_Mediums_ indefinitely, not to make the Trials with _Mediums_ of two greatthickness: where it is made to appear, that Cold is able to operate throughMetalline Vessels, which is confirmed by a very pretty Experiment of making_Icy Cups_ to drink in, whereof the way is accurately set down. Then arerelated the Trials, whether, or how, Cold will be diffused through a_Medium_, that _some_ would think a _Vacuum_, and which to _others_ wouldseem much less disposed to assist the diffusion of Cold, than Common Air itself. After which follows a curious Experiment, shewing whether a Cold Bodycan operate through {51} a _Medium_ actually hot, and having its heatcontinually renewed by a fountain of heat. 12, How to estimate the solidity of the Body of Ice, or how strong is themutual adhesion of its parts? and whether differing Degrees of Cold may notvary the Degree of the compactness of Ice. And our Author having proceededas far as he was able towards the bringing the strength of Ice to someEstimate by several experiments, he communicateth the information, he couldget about this matter among the Descriptions that are given us of coldRegions: and then he relateth out of Sea-mens _Journals_, theirObservations touching the insipidness of resolved Ice made of Sea-water;and the prodigious bigness of it, extending even to the height of twohundred and forty Foot above water, and the length of above eight Leagues. To which he adds some promiscuous, but very notable Observations concerningIce, not so readily reducible to the foregoing Heads: _videlicet_, Of theblew colour of Rocky pieces of Ice; and the horrid noise made by thebreaking of Ice, like that of Thunder and Earthquakes, together with aConsideration of the cause, whence those loud Ruptures may proceed. 13, How Ice and Snow may be made to last long; and what Liquor dissolvesIce sooner than others, and in what proportion of quickness the Solutionsin the several Liquors are made, where occasion is offered to the Author, to examine, whether Motion will impart a heat to Ice? After which herelates an Experiment of _Heating_ a _Cold_ Liquor with Ice, made byhimself in the presence of a great and Learned Nobleman, and his Lady, whofound the Glass wherein the Liquor was, so hot that they could not endureto hold it in their Hands. Next it is examined, whether the effects of Colddo continually depend upon the actual presence and influence of themanifest Efficient causes, as the Light of the Air depends upon the Sun orFire, or other Luminous Bodies. To this is annexed an Account of the_Italian_ way of making _Conservatories_ of Ice and Snow, as the Author hadreceived it from that Ingenious and Polite Gentleman, Master _J. Evelyn_. {52} But want of time prohibiting the accomplishment of the intended account ofthis Rich Piece: what remains, must be referred to the next Occasion. Itshall only be intimated for a Conclusion, that the _Author_ hath annexed tothis _Treatise_, an Examen of Master _Hob_'s Doctrine touching _Cold_;wherein the _Grand_ Cause of _Cold_ and its Effects is assigned to _Wind_, in so much that 'tis affirmed, that almost any Ventilation and stirring ofthe Air doth refrigerate. * * * * * _LONDON, _ Printed with Licence, By _John Martyn_, and _James Allestry_, Printers tothe _Royal-Society_, 1665 {53} * * * * * _Numb. _ 4. PHILOSOPHICAL_TRANSACTIONS. _ * * * * * _Munday_, _June_ 5. 1665. * * * * * The Contents. _A Relation of some extraordinary Tydes in the _West Isles_ of _Scotland_, by Sr. _Robert Moray_. The judgment of Monsieur _Auzout_, touching the _Apertures_ of _Object-glasses_, and their _proportions_ in respect of the several lengths of _Telescopes_; together with a _Table_ thereof. Considerations of the same Person upon Mr. _Hook's_ New Engine for grinding of _Optick-glasses_. Mr. _Hook's_ Thoughts thereupon. Of a means to illuminate an _Object_ in what proportion one pleaseth; and of the _distances_, that are requisite to burn Bodies by the _Sun_. A further accompt by Monsieur _Auzout_ of Signior _Campani_'s Book, and Performances about _Optick-Glasses_. _Campani_'s Answer thereunto; and Mr. _Auzout_'s Animadversions upon that Answer. An accompt of Mr. _Lower_'s newly published _Vindication_ of Dr. _Willis_'s Diatriba de _Febribus_. _ * * * * * _A Relation of some extraordinary Tydes in the West-Isles of _Scotland_, asit was communicated by Sr. _Robert Moray_. _ In that Tract of _Isles_, on the West of _Scotland_, called by theInhabitants, the _Long-Island_, as being about 100. Miles long from _North_to _South_, there is a multitude of small Islands, situated in a _Fretum_, or _Frith_, that passes between the Island of _Eust_, and the _Herris_;amongst which, there is one called _Berneray_, some three miles long, and{54} more than a mile broad, the length running from _East_ to _West_, asthe _Frith_ lyes. At the _East_ end of this _Island_, where I stayed some16. Or 17. Dayes, I _observed_ a very strange Reciprocation of the Flux andRe-flux of the Sea, and _heard_ of another, no less remarkable. Upon the _West_ side of the _Long Island_, the Tides, which came from the_South-west_, run along the Coast, _Northward_; so that during the ordinarycourse of the Tides, the Flood runs _East_ in the _Frith_, where _Berneray_lyes, and the Ebb _West_. And thus the Sea ebbs and flows orderly, some 4. Days before the _full Moon_, and _change_, and as long after (the ordinarySpring-tides rising some 14. Or 15. Foot upright, and all the restproportionably, as in other places). But afterwards, some 4. Days beforethe _Quarter-moons_, and as long after, there is constantly a great andsingular _variation_. For _then_, (a _Southerly_ Moon making there the fullSea) the course of the Tide being _Eastward_, when it begins to flow, whichis about 9½ of the Clock, not onely continues so till about 3½ in theafternoon, that it be high water, but, after it begins to ebb, the Currentruns on still _Eastward_, during the whole Ebb; so that it runs _Eastward_12 hours together, that is, all day long, from about 9½ in the morning, tilabout 9½ at night. But then, when the night-Tide begins to flow, theCurrent turns, and runs _Westward_ all night, during both Floud & Ebb, forsome 12. Hours more, as it did _Eastward_ the day before. And thus theReciprocations continue, one Floud and Ebb, running 12 hours _Eastward_, and another twelve hours _Westward_, till 4. Days before the _New_ and_Full_ Moon; and then they resume their ordinary regular course as before, running _East_, during the six hours of Floud, and _West_, during the sixof Ebb. And this I observed curiously, during my abode upon the place, which was in the Moneth of _August_, as I remember. But the Gentleman, to whom the _Island_ belongs at present, and divers ofhis Brothers and Friends, knowing and discreet persons, and expert in allsuch parts of Sea-matters, as other _Islanders_ commonly are, though Ishrewdly suspected their skill in Tides, when I had not yet seen what theytold me, and I have now related of these irregular Courses of the Tides, did most confidently assure me, and so did every body I spake with {55}about it, that there is yet another irregularity in the Tides, which neverfails, and is no less extraordinary, than what I have been mentioning:which is, That, whereas between the _Vernal_ and _Autumnal Equinoxes_, thatis, for six Moneths together, the Course of irregular Tides about theQuartermoons, is, to run all day, that is, twelve hours, as from about 9½to 9½, 10¼ to 10¼ _&c. Eastward_, and all night, that is, twelve hoursmore, _Westward_: during the other six Moneths, from the _Autumnal_ to the_Vernal Equinox_, the Current runs all day _Westward_, and all Night_Eastward_. Of this, though I had not the opportunity to be an Eye-witness, as of theother, yet I do not at all doubt, having received so credible Informationof it. To penetrate into the _Causes_ of these strange Reciprocations of theTides, would require exact descriptions of the Situation, Shape, and Extentof every piece of the adjacent Coasts of _Eust_ and _Herris_; the Rocks, Sands, Shelves, Promontorys, Bays, Lakes, Depths, and other Circumstanceswhich I cannot now set down with any certainty, or accurateness; seeing, they are to be found in no _Map_, neither had I any opportunity to surveythem; nor do they now occur to my Memory, as they did some years ago, whenupon occasion I ventured to make a _Map_ of this whole _Frith_ of_Berneray_, which not having copied, I cannot adventure to beat it outagain. * * * * * __Monsieur Auzout_'s Judgment touching the Apertures of _Object-Glasses_, and their _Proportions_, in respect of the several _Lengths_ of_Telescopes_. _ This Author, observing in a small _French Tract_ lately written by him to aCountryman of his, Monsieur _L' Abbe Charles_; That great _Optick Glasses_have almost never as great an _Aperture_ as the small ones, in proportionto what they Magnifie, and that therefore they must be more dim; takesoccasion to inform {56} the _Reader_, that he hath found, that the_Apertures_, which _Optick-Glasses_ can bear with distinctness, are inabout a _subduplicate proportion_ to their _Lengths_; whereof he tells ushe intends to give the reason and demonstration in his _Diopticks_, whichhe is now writing, and intends to finish, as soon as his Health willpermit. In the mean time, he presents the _Reader_ with a _Table_ of such_Apertures_; which is here exhibited to the Consideration of the Ingenious, there being of this _French_ Book but one Copy, that is known, in_England_. A _TABLE_ of the _Apertures_ of _Object-Glasses_. _The Points put to some of these Numbers denote Fractions. _ Lengths of |For excellent| For good |For ordinary | Glasses. | ones. | ones. | ones. | Feet, Inches. |Inch, Lines. |Inch, Lines. |Inch, Lines. | | | | | 4| 4. | 4| 3| 6| 5. | 5| 4| 9| 7| 6| 5| 1 0| 8. | 7| 6| -------------|-------------|-------------|-------------| 1 6| 9| 8. | 7| 2 0| 11| 10| 8| 2 6|1 0| 11| 9| 3 0|1 1|1 0| 10| -------------|-------------|-------------|-------------| 3 6|1 2. |1 1| 11| 4 0|1 4|1 2|1 0| 4 6|1 5|1 3|1 . | 5 0|1 6|1 4|1 1. | -------------|-------------|-------------|-------------| 6 |1 7. |1 5|1 2| 7 |1 9|1 6|1 3| 8 |1 10|1 8|1 4| 9 |1 11. |1 9|1 5| -------------|-------------|-------------|-------------| 10 |2 1|1 10|1 6| 12 |2 4|2 0|1 8| 14 |2 6|2 2|1 9. | 16 |2 8|2 4|1 11. | 18 |2 10|2 6|2 1| 20 |3 0|2 7|2 2. | -------------|-------------|-------------|-------------| 25 |3 4|2 10|2 4. | 30 |3 8|3 2|2 7| 35 |4 0|3 4. |2 10| 40 |4 3|3 7|3 . | -------------|-------------|-------------|-------------| 45 |4 6|3 10|3 2. | 50 |4 9|4 0|3 4. | 55 |5 0|4 3|3 6. | 60 |5 2|4 6|3 8. | -------------|-------------|-------------|-------------| 65 |5 4|4 8|3 10| 70 |5 7|4 10|4 . | 75 |5 9|5 0|4 2. | 80 |5 11|5 2|4 5| -------------|-------------|-------------|-------------| 90 |6 4|5 6|4 7. | 100 |6 8|5 9|4 10| 120 |7 5|6 5|5 3| 150 |8 0|7 0|5 11| -------------|-------------|-------------|-------------| 200 |9 6|8 0|6 9| 250 |10 6|9 2|7 8. | 300 |11 6|10 0|8 5| 350 |12 *6. |10 9|9 0| 400 |13 4|11 6|9 8| -------------+-------------+-------------+-------------+ {57} * * * * * _Considerations of Monsieur _Auzout_ upon Mr. _Hook_'s New Instrument forGrinding of _Optick-Glasses_. _ In the above-mentioned _French_ Tract, there are, besides several otherparticulars, to be represented in due place, contained some_Considerations_ of Monsieur _Auzout_ upon Mr. _Hook_'s New _Engine_ forgrinding _Optick-Glasses_. Where he premises in _General_ his thoughtstouching the working of _Great_ Optick-Glasses, and that by the help of a_Turn lathe_; affirming first of all, that not only the _Engin_ is to beconsidered for giveing the _Figure_, but the _Matter_ also, which ought tobe brought to greater perfection, than it hath been hitherto. For, he findsit not so easie (as least, _where he is_) to procure _Great_ pieces ofGlass without _Veins_, and other faults, nor to get such, as are thickenough without _Blebbs_; which, if they be not, they will yield to thepressure and weight, either when they are fitted to the _Cement_, orwrought. Secondly, He finds it difficult to work these _Great_ Glasses of the _same_thickness, which yet is very necessary, because, that the least differencein _Figures_ so little _convex_, can put the _Center_ out of the _Midle_, 2or 3 _Inches_; and if they be wrought in _Moulds_, the length of time, which is required to wear and to smooth them, may spoil the best _Mould_, before they be finished. Besides, that the strength of Man is so limited, that he is unable to work Glasses beyond a certain bigness, so as to finishand polish them all over so well, as _small_ Glasses; whereas yet, thebigger they are, the more compleat they ought to be: And if any weight orEngine be used to supply strength, there is then danger of an unequalpressure, and of wearing away the Engine; In the mean time, the precisenessand delicateness is {58} greater than can easily be imagined. Wherefore hecould never, having some experience of this preciseness, conceive, that a_Turn-lathe_, wherein must be two different, and in some manner contrarymotions, can move with that exactness and steddiness, that is required, especially, for any considerable length of time. Having premised this, he discourses upon Mr. _Hook_ his _Turne_, intimatingfirst of all, that he was impatient to know what kind of _Turne_ this was, imagining, that it had been tried, and had succeeded, as coming from aSociety that professeth, they publish nothing but what hath been maturelyexamin'd. But that he was much surprised when he saw the _Micrography_ ofMr. _Hook_, and found there, that his _Engine_ was published upon a _meerTheory_, without having made any Experiment, though that might have beenmade with little charge and great speed; expence of Money and Time beingthe onely thing, that can excuse those who in matter of _Engines_ imparttheir inventions to the publick, without having tried them, to exciteothers to make trial thereof. Whereupon he proposes some difficulties, to give the _Inventor_ occasion tofind a way to remove them. He affirms therefore, that though it be true inthe _Theory_, that a _Circle_, whose _Plain_ is inclined to the _Axis_ ofthe _Sphere_ by an _Angle_, whereof half the _Diameter_ is the _Sine_, andwhich touches the _Sphere_ in its _Pole_, will touch in all its parts a_spherical Surface_, that shall turn upon that _Axe_. But that it is truealso, that that must be but a _Mathematical Circle_, and without _Breadth_, and which precisely touches the Body in its middle: Whereas in thepractice, a _Circle_ capable to keep Sand and Putty, must be of some_breadth_; and he knows not whether we can find such a dexterity of keepingso much of it, and for so long a time, as needs, upon the Brim of a _Ring_that is half an Inch broad. He adds, that it is very difficult to contrive, that the middle of the Glass do always precisely answer to the Brim of this_Ring_, seeing that the position of the Glass does always change a littlein respect of the _Ring_, in proportion as 'tis worn, and as it must bepressed because of its inclination. He believes it also very hard, to giveto the _Axis_ or to the _Mandril_, which holds the Glass, that little {59}_Inclination_, that would be necessary for great Glasses, and to make thetwo _Mandrils_ to have one and the same _Plain_, as is necessary. And, having done all this, he persuades himself, that it is exceedinglydifficult, if not impossible, for two contrary motions, where so manypieces are, to rest for a long time steddy and firm, as is requisite forthe not swarving from it a hair's thickness, since less than that canchange all. He goes on, and, seeing that this _Inventor_ speaks of Glasses of athousand, & ten thousand foot, which he supposed not impossible to be madeby this _Engine_, discourses of what is necessary for the making Glasses ofsuch bignesses; which he believes this _Inventor_ may perhaps not havethought of. Wherefore he affirms, that if the _Table_, made by himself forthe _Apertures_ of Glasses (which is that, that is above delivered) becontinued unto a thousand feet, by taking always the _Subduplicateproportion_ of _Lengths_, it will be found, that for pretty good ones, the_Aperture_ must be of 15. Inches; for good ones, more than 18. And for suchas are excellent, more than 21. Inches: whence it may be judged, what pieceof Glass, and of what thickness it must be, to endure the working. But heproceeds to speak of the _Inclination_, which the _Mandril_ must have uponthe _Plain_ of the _Ring_, when the _Ring_ should have 10. Or 12 Inches;and finds, that it would make but 6 or 7. Minutes of inclination, and thata Glass would have less _Convexity_, and consequently, less difference froma Glass perfectly plain, than the 7. Or 8. Part of a Line. And then heleaveth it to be judged, whether a Glass of such a Length being found, weought to hope, that a _Turn_ can be firm enough to keep such a piece ofGlass in the same Inclination, so that a _Mandril_ do not recede someMinutes from it: and, though even the Glass could be fastned perfectlyperpendicular to the _Mandril_, that those two _Mandrils_ could be put inone and the same Plain, & that that little Inclination, which is requisite, could be given, and the _Mandril_ be continued to be pressed in that same_Inclination_, according as the Glass is worn. All which particulars, heconceives to be very hard in the practice; not to mention, that the weightof the Glass, that should be inclined to the _Horizon_, as 'tis representedby Mr. _Hook_, would make it slide upon the _Cement_, and so {60} changethe _Center_; and that the Glass is not pressed at the same time by the_Ring_ but in one part on the side, _vid. _ about a fourth; and that theparts of the Glass are not equally worn away, &c. What then, _saith he_, would becom of a Glass of 10000 feet, which, according to the said Table, would have more than four feet, or four feet and nine inches, or five feet, seven inches _Aperture_, and of which the _Ring_, though it were two feetnine inches, would have but one minut of _Inclination_, and the Glass of 5feet _Aperture_ would have but 4 minuts, and the curvity of it would beless than the eight part of a Line. But, _saith he_, let us consider, only a Glass of 300 foot, to see, what isto be hoped of that, and to know at least the difficulty, to be met with inmaking a Glass only of that Length. A Glass then of 300 foot, according tohis Table, must have more than 8 inches _Aperture_, which maketh but 16minuts of its _Circle_, and it should have more than 11 inches, if it be anexcellent one. If Mr. _Hook_ (adds he) did use but his _Ring_ of 6 inches, which he would use from twelve to an hundred foot Glass, the _Inclination_, which the _Axis_, or _Mandril_, that bears his Glass, should have, shouldbe but 16 minuts, and the _Curvity_ of the Glass would be less than theeighth part of a Line, and if he should use a bigger, the _Inclination_would be proportionable. Whence it may be judged (continues he) that we are yet very far from seeing_Animals &c. _ in the _Moon_, as Monsieur _Des Cartes_ gave hope, and Mr. _Hook_ despairs not of. For, he believes by what he knows of _Telescopes_, that we are not to look for any above 300 or 400 foot at most; and hefears, that neither _Matter_ nor _Art_ will go even so far. When therefore (_saith he_) a Glass of 300 foot should bear an Eye-glass of6 inches (which would appear wonderful) it would magnifie but 600. Times in_Diameter_, that is, 360000 times in _Surface_: but suppose, that suchcould be made, as would magnifie a 1000 times in _Diameter_, and 1000000. Of times in _Surface_, admitting there were but 60000 leagues from the_Earth_ to the _Moon_, and that the smalness of the _Aperture_ of theGlasses (which yet would diminish the Light more than 36 times) and theobstacle of the Air were not considered, we should not {61} see the _Moon_, but as if we were a 100, or at least, 60. Leagues distant from her withouta Glass. He here wishes, that those, that promise to make us see _Animals_and _Plants_ in the Moon, had thought on what our naked Eyes can make usdiscern of such Objects, only at 10 or 12 leagues distance. But this he would not have understood as a discouragement from searchingwith all care and earnestness after the means of making long _Telescopes_, or of facilitating the working thereof; but only as an Advertisement tothose, who light upon the _Theory_ of any _Engine_, not to expose itpresently as possible and useful, before they have tried it, or if it havesucceeded in small, not to endeavour to persuade, that it will also succeedin great. As it may happen (_saith he_) that the Engin of Mr. _Hook_ may, by usingall necessary precautions, succeed in the making of _Eye-Glasses_, or_small_ Optick-Glasses, but not in making _great_ ones; as we see, that aninstrument composed of two Rulers, wherewith are traced Portions ofCircles, succeeds well enough in _small_, but when there is no more thanhalf a Line, a quarter of a Line, or less convexity, it will be no longerjust at all, as he tells us to have made the proof of it in Circles drawnby the means of one of these Instruments, made by one of the best Workmenin his time, who, whilst he lived, esteemed them above price, although theybe not just; as others and my self (_saith he_) have by tryal found, whenwe endeavoured to make _Moulds_ by their means, & as those, who by the likeInstrument laboured to trace portions of Circles of 80 or 100 foot, _&c. Diameter_, can attest. But, notwithstanding all this, he hath thought upon two or three things, which he thinks may remedy some inconveniencies of Mr. _Hook_ his _Turn_. The _first_ is, to invert the Glass, and to put it under the _Ring_, thatso not only the Glass may be placed more _Horizontally_, and not slide uponthe _Cement_, but that the _Sand_ also, and the _Putty_ may stay upon theGlass. The _other_ is, that there must be two _Poppetheads_, into which the_Mandril_ must pass, where the _Ring_ is to be fastned; and the _Mandril_must be perfectly _Cylindrical_, that so it may advance upon the Glass asit wears away by the means of its weight, or by the means of a spring, pressing it, without wrigling from one place to another, as it wouldpresently happen in the fashion, {62} as the _Turn_ is composed. For, whenthe Glasses do wear, especially when they are very _convex_, it cannot beotherwise, but the _Mandril_ will play and wrigle, before the _Scrue_ bemade firm. But he doubts, whether all can be remedied, which he leavs to the industryof Mr. _Hook_, considering what he saith in the _Preface_ of his_Micrography_, touching a Method, he knows, of finding out as much in_Mechanicks_, as can be found in _Geometry_ by _Algebra_. Besides this, he taketh notice, that most of those that medle with_Optick-Glasses_, give them not as much _Aperture_, nor charge them so deepas they ought. And he instances in the _Telescope_, which His _Majesty_ of_Great Britain_ presented the _Duke_ of _Orleans_ with, _videl. _ that itdid bear but 2 inches, and 9 lines _French_, for its greatest _Aperture_, though there be 5 or 6 lesser _Apertures_, of which it seems (_saith he_)the Artificer would have those, that use it, serve themselves moreordinarily, than of the greatest; which conveys but almost half as manyRays as it should do, according to his Calculation, which is, as 9 to 16;Whereas, according to his _Table_ of _Apertures_, an excellent 35 foot_Telescope_ should bear 4 inches _Aperture_ in proportion to _excellent_small ones. He notes also, that the Eye-glass of the said _Telescope_, composed of 2 Glasses, hath no more effect, when it is most charged, than aGlass of 4½ inches; which makes it magnifie not a 100 times. And he findsby Mr. _Hook_, that he esteems a _Telescope_ made in _London_ of 60 feet, (which amount to about 57 feet of _France_, the foot of _France_ being tothat of _England_ as about 15 to 16) because it can bear at least 3_English_ inches _Aperture_, and that there are few of 30 feet, that canbear more than 2 inches, (which is but 22½ Lines _French_) although he (M. _Auzout_) gives no less _Aperture_ than so, to a 15 foot-_Telescope_, andhis of 21 feet hath ordinarily 2 Inches, 4 Lines, or 2 inches, 6 Lines_Aperture_. This Discourse he Concludeth with exhorting those, that work_Optick-Glasses_, to endeavor to make them such, that they may bear great_Apertures_ and deep Eye-glasses; seeing it is not the length that givesesteem to _Telescopes_; but on the contrary renders them less estimable, byreason of the trouble {63} accompanying them, if they perform no more, thanshorter ones. Where, by the by, he takes notice, that he knows not yet, what _Aperture_ Signor _Campani_ gives to his Glasses, seeing he hath asyet signified nothing of it; but that the small one, sent by him toCardinal _Antonio_, hath no more _Aperture_, than ordinary ones ought tohave. He promises withall, that he will explicate this way in his _Treatise ofthe usefulness of Telescopes_, where he intends to assign the Bigness ofthe _Diameter_ of all the _Planets_, and their proportion to that of the_Sun_; as also, that of the _Stars_, which he esteems yet much less, thanall those have done, that have written of it hitherto; not believing, thatthe _Great Dog_, which appears to be the fairest Star of the _Firmament_, hath 2 _Seconds_ in _Diameter_, nor that those, which are counted of thesixth Magnitude, have 20 _thirds_; nor thinking, that all the Stars, thatare in the _Firmament_, do enlighten the Earth as much as a Luminous Bodyof 20 _seconds_ in _Diameter_ would do, or, because there is but one halfof them at the same time above our _Horizon_, as a Body of 14 _seconds_ in_Diameter_; and as the 18432^{th} part of the _Sun_ would enlighten us, oras the _Sun_ would do, if we were 14 times more distant from it, than_Saturn_, and 137 times further, than the Earth: Which, _he saith_, wouldnot be credible, if he did not endeavor to evince it both by _Experience_and _Reason_. And he doubts not, but that _Venus_, although she sends us noLight but what is reflected, does sometimes enlighten the _Earth_ more, than all the Stars together. Yet he would not have us imagine, from what hehath spoken of the smallness of the Stars, that _Telescopes_ do notmagnifie them by reason of their great distance, as they do _Planets_; forthis he judgeth a Vulgar Error, to be renounced. _Telescopes_ magnifie the_Stars_ (_saith he_) as much in proportion, as they do all other Bodies, seeing that the demonstration of their magnifying is made even upon_Parallel_ rays, which do suppose an infinite distance, though the Starshave none such: And if the _Telescopes_ did not magnifie the Stars, howcould they make us see some of the _fiftieth_, and it may be some of the_hundreth_, and _twohundreth_ Magnitude, as they do, and as they would shewyet much lesser ones, if they did magnifie more? {64} * * * * * __M^r. Hook_'s Answer to Monsieur _Auzout_'s Considerations, in a Letter tothe Publisher of these _Transactions_. _ _SIR_, Together with my most hearty thanks for the favour you were pleased to dome, in sending me an _Epitome_ of what had been by the ingenious Monsieur_Auzout_ animadverted on a description, I had made of an _Engine_ for_grinding spherical Glasses_, I thought my self obliged, both for yoursatisfaction, and my own Vindication, to return you my present thoughtsupon those Objections. The chief of which seems to be against the very_Proposition_ it self: For it appears, that the _Objector_ is somewhatunsatisfied, that I should propound a thing in _Theory_, without havingfirst tried the _Practicableness_ of it. But first, I could wish that thisworthy Person had rectified my mistakes, not by speculation, but byexperiments. Next, I have this to answer, that (though I did not tell the_Reader_ so much, to the end that he might have the more freedom to examineand judg of the contrivance, yet) it was not meer _Theory_ I propounded, but somewhat of _History_ and _matter of Fact_: For, I had made trials, asmany as my leisure would permit, not without some good success; but nothaving time and opportunity enough to prosecute them, I thought it wouldnot be unacceptable to such, as enjoyed both, to have a description of away altogether _New_, and _Geometrically_ true, and seemingly, notunpracticable, whereof they might make use, or not, as they should seereason. But nothing surprised me so much, as, that he is pleased (after hehad declared it a fault, to write this _Theory_, without having reduced itto practice) to lay it, as he seems to do, in one place of his book, _p. _22 upon the _Royal Society_. Truly, _Sir_, I should think my self mostinjurious to that _Noble Company_, had I not endeavoured, even in thebeginning of my Book, to prevent such a misconstruction. And therefore Icannot but make this interpretation of what Monsieur _Auzout_ saith in thisparticular, that either he had not so {65} much of the Language wherein Ihave written, as to understand all what was said by me, or, that he had notread my _Dedication_ to the _Royal Society_, which if he had done, he wouldhave found, how careful I was, that that _Illustrious Society_ should notbe prejudiced by my _Errors_, that could be so little advantaged by my_Actions_. And indeed, for any man to look upon the matters published bytheir Order or Licence, as if they were _Their_ Sense, and had _Their_Approbation, as _certain_ and _true_, 'tis extremely wide of theirintentions, seeing they, in giving way to, or encouraging suchpublications, aim chiefly at this, that _ingenious conceptions_, andimportant _philosophical matter of Fact_ may be communicated to the learnedand enquiring World, thereby to excite the minds of men to the examinationand improvement thereof. But, to return; As to his _Objections_ against the_Matter_, I do find that they are no more against mine, than any other wayof _Grinding Glasses_; nor is it more than I have taken notice of my selfin this Passage of the same _Paragraph_, of which sort are also thosedifficulties he raises about _Long Glasses_, which are commonly known tosuch, as are conversant in making them _It would be convenient also_ (theseare my words) _and not very chargeable, to have four or five several Tools:One, _ &c. _And, if curiosity shall ever proceed so farr, one for alllengths, between 1000. And 10000. Foot long; for indeed, the _Principle_ issuch, that supposing _the Mandrils well_ made, and of a good length, andsupposing _great care_ be used in working and polishing them, I see noreason, but that a Glass of 1000. Nay, 10000. Foot long may be made, aswell as one of 10. For, the reason is the same, supposing the _Mandrils_and _Tools_ be made sufficiently strong, so that they cannot bend; andsupposing also that the Glass out of which they are wrought, be capable ofso great a regularity in its parts, as to its Refraction. _ But next, I mustsay that his _Objections_ to me, seem not so considerable, as perhaps heimagines them. For, as to the possibility of getting Plates of Glass thickand broad enough without veins, I think _that_ not now so difficult here in_England_, where I believe is made as good, if not much better Glass for_Optical Experiments_, than ever I saw come from _Venice_. Next, though itwere better, that the thickest part of a long _Object-Glass_ were exactlyin the middle, yet I can assure Monsieur _Auzout_, that it may be a very{66} good one, when it is an Inch or two out of it. And I have a good oneby me at present, of 36. Foot, that will bare an _Aperture_, if _Saturn_ orthe _Moon_ in the _twilight_, be look'd on with it, of 3½ Inches over, andyet the thickest part of the Glass is a great way out of the middle. And Imust take the liberty to doubt, whether ever my _Animadversor_ saw a longGlass, that was otherwise; as he might presently satisfie himself by a wayI could shew him (if he did not know it) whereby the difference of thethickness of the sides might be found to the hundreth part of a Line. As to the exceeding exactness of the _Figure_ of Long _Object-Glasses_, 'tis not doubted, but that it is a matter difficult enough to be attainedany way: but yet, I think, much easier by _Engine_, than by _Hand_; and ofall _Engines_, I conceive, none more plain and simple, than that of a_Mandril_. And for making _spherical Glasses_ by an _Engine_, I am apt tothink, there hardly can be any way more plain, and more exact, than thatwhich I have described; wherein there is no other motion, than that of twosuch _Mandrils_, which may be made of sufficient strength, length, andexactness, to perform abundantly much more, than I can believe possible tobe done otherwise than by chance, by a man's hands or strength unassistedby an _Engine_, the motion and strength being much more certain andregular. I know very well, that in making a 60. Foot Glass by the strengthof the hand, in the common way, not one of ten that are wrought, willhappen to be good, as I have been assured by Mr. _Reeves_; who, I am apt tothink, was the first that made any good of that length. For the _Figure_ ofthe _Tool_ in that way is presently vitiated by the working of the Glass, and without much _gaging_ will not do any thing considerable. Besides, thestrength of a man's hands, applied to it for the working and polishing ofit, is very unequal, and the motions made, are very irregular; but in theway, I have ventured to propose, by _Mandrils_, the longer the _Glass_ and_Tool_ are wrought together, the more exact they seem to be and if allthings be ordered, as they should be, the very polishing of the Glass, doesseem most of all rectifie the _Figure_. As to what he objects, that the Tool does only touch the Glass in a_Mathematical Circle_; that is true, perhaps, at first, but before theGlass is wrought down to its true _Figure_, the _Edge_ of the _Tool_ {67}will be worn or grownd away, so as that a Ring of an inch broad may be madeto touch the _Spherical Surface_ of the Glass; nay, if it be necessary(without much trouble, especially in the grinding of longer Glasses) thewhole _Concave Surface_ of the _Tool_ may be made to touch a Glass. Besides, that as to the keeping a quantity of the same sand and Powders ofseveral finesses, according as the glass wears, the same is possible to bedon, as with the same Sand wrought finer by working in the Ordinary way. The giving the _Inclination_ to the _Mandrils_, is not at all difficult;though perhaps to determine the length exactly which the Glass so madeshall draw, is not so easie: But 'tis no matter, what length the Glass beoff, so it be made good, whether 60 or 80 foot, or the like. Nor is it sovery difficult, to lay them both in the same _Plain_. And to keep them_steddy_, when once fix'd, is most easie. As to the Calculation of the propriety of a Glass of a thousand foot, perhaps for that particular Length, I had not, nor have as yet calculated, that the Convexity of one of eighteen inches broad, will not be above aseventh part of a Line. But it does not thence follow, that I had notconsidered the difficulties, that would be in making of it. For, I musttell him, that I can make a _Plano convex_ Glass though its convexity be asmaler sphere than is usual for such a length to be an _Object-Glass_ ofabout 150 foot in Length, nay of 300 foot, and either longer or shorter, _without_ at all _altering the convexity_. So that, if he will by anyContrivance he hath, give me a _Plano-convex_ Glass of 20, or 40 foot_Diameter_, without _Veins_, and truly wrought of that _Figure_, I willpresently make a _Telescope_ with it, that with a single Ey-glass shalldraw a thousand foot: Which _Invention_, I shall shortly discover, therebeing, I think, nothing more easie and certain. And if a _Plano-convex_Glass can be made of any _Sphere_ between twenty and fourty foot _radius_, so as that both the _Convex_ and _Plain_ side of the Glass be exactlypolish'd of a true _Figure_, I will shortly shew, how therewith may be madea _Telescope_ of any Length, supposing the Glass free from all kind of_Veins_, or inequality of _Refraction_. As for the sliding of the Glass upon the _Cement_, I see no reason at allfor it, at least in the _Cement_, I make use of, having never observed anysuch accident in hard _Cement_. {68} And for the Bearing of the _Ring_ against one side of the Glass only at atime, I cannot see, why _that_ should produce any inequality, since all thesides of the Glass have successively the same pressure. His ratiocination concerning a Glass of 300 foot, is much the same with theformer, about the difficulty of working a true surface of a convenientfigure; which how considerable both _that_ and his Conclusion thereupon(_videl. That we are not to expect Glasses of above 300 or 400 foot long atmost, and that neither _Matter_ nor _Art_ will go so far_) is, may bejudged from what I have newly told you of making any _Object-Glass_ of anyLength. And for his good wishes, that those, who promise to make him see _Plants_or _Animals_ in the _Moon_ (of which I know not any, that has done so, though perhaps there may be some, notwithstanding his Objections, that donot yet think it impossible to be done) had considered, what a Man is ableto see with his _bare_ Eye at 60 Leagues distance: I cannot but return himmy wishes, that he would consider the difference between seeing a thingthrough the _Gross_ and _Vaporous_ Air neer the Earth, and through the Airover our heads: Which, if he observe the Moon in the _Horizon_, and neerthe _Zenith_ with a _Telescope_, he will experimentally find; and, havingdone so, he will perhaps not be so dissident in this matter. Concerning his Advertisement to such, as publish _Theories_, I find not, that he hath made use of it in his own case. For, in his _Theory_ about_Apertures_ he seems to be very positive, not at all doubting to rely uponit, _vid. _ that the _Apertures_ must be _thus_ and _thus_ in _great_Glasses, because he had found them _so_ or _so_ in some _small_ ones. For his Proposal of amendments of some inconveniencies in this way, Ireturn him my thanks; but as to his first I believe, that the matter may beconteined as wel in the _Concave_ Tool, as on the _convex_ Glass. And as tothat of 2 _Poppet-heads_ I do not well understand it, if differing frommine; and the keeping of the Tool upon the Glass with a spring or weight, must quickly spoyl the whole; since, if either of the _Mandrils_ willeasily yield backwards, the _regularity_ of _all_ will be spoiled: and asto the wrigling and playing of the _Mandril_, I do not at all apprehend it. {69} His _Theory_ of _Apertures_, though he seems to think it very authentick, yet to me it seems not so cleer. For, the same Glass will endure greater orlesser _Apertures_, according to the lesser or greater Light of the_Object_: If it be for the looking on the _Sun_ or _Venus_, or for seeingthe _Diameters_ of the _Fix'd Stars_, then smaller _Apertures_ do better;if for the _Moon_ in the _daylight_, or on _Saturn_, or _Jupiter_, or_Mars_, then the largest. Thus I have often made use of a 12 foot-Glass tolook on _Saturn_ with an _Aperture_ of almost 3 inches, and with a singleEye-glass of 2 inches _double convex_: but, when with the same Glass Ilooked on the _Sun_ or _Venus_, I used both a smaller _Aperture_, andshallower _Charge_. And though M. _Auzout_ seems to find fault with the_English_ Glass of 36 foot, that had an _Aperture_ of but 2¾ inches_French_; as also, with a 60 foot _Tube_, used but with an _Aperture_ of 3inches; yet I do not find, that he hath seen Glasses of that length, thatwould bear greater _Apertures_, and 'tis not impossible, but his _Theory_of _Apertures_ may fail in longer Glasses. * * * * * _Of a means to illuminate an Object in what proportion one pleaseth; and ofthe Distances requisite to burn Bodies by the _Sun_. _ One of the means used by M. _Auzout_ to enlighten an Object, in whatproportion one pleaseth, is by some great _Object-Glass_, by him called a_Planetary_ one, because that by it he shews the difference of Light, whichall the _Planets_ receive from the _Sun_, by making use of several_Apertures_, proportionate to their distance from the _Sun_, provided thatfor every 9 foot draught, or thereabout, one inch of _Aperture_ be givenfor the _Earth_. Doing this, one sees (_saith he_) that the Light which_Mercury_ receives, is far enough from being able to burn Bodies, and yetthat the same Light is great enough in _Saturn_ to see cleer there, seeingthat (to him) it appears greater in _Saturn_, than it doth upon our_Earth_, when it is overcast with Clouds: Which (he adds) would scarce bebelieved, if by means of this Glass it did not sensibly appear so; Whereofhe promises to discourse more fully in his {70} _Treatise of the usefulnessof great Optick-Glasses_, where he also intends to deliver severalExperiments, by him made, 1. Touching the quantity of Light, which a Body, that is 10, 15 and 20 times, &c. Remoter than _Saturn_, would yet receivefrom the _Sun_. 2. Touching the quantity of Light, by which the _Earth_ isilluminated even in the _Eclipses_ of the _Sun_, in proportion of theirbigness. 3. Touching the quantity of Light, which is necessary to burnBodies: he having found, that not abating the Light, which is reflected bythe Surfaces of the Glass (whereof he confesseth, he doth not yet exactlyknow the quantity) there would be necessary about 50 times as much Light, as we have here, for the burning of _Black_ Bodies; and neer 9 times morefor the burning of _White_ Bodies, than for the burning of _Black_ ones:and so observing the immediate proportions between these two, for burningbodies of _other_ Colors. Whence (he tells us) he hath drawn someconsequences, touching the distance, at which we may hope, to burn Bodieshere, by the means of _great Glasses_ and great _Looking-glasses_. So that(_saith he_) we must yet be seven times neerer the _Sun_, than we are, tobe in danger of being burned by it. Where he mentions, that having given_Instructions_ to certain persons, gon to travel in _Hot Countries_, hehath among other particulars recommended to them, to try by means of great_Burning-glasses_, with how much less _Aperture_ they will burn _there_, than _here_, to know from thence, whether there by more Light _there_ than_here_, and how much; since this perhaps may be the only means of tryingit, supposing, the same matters be used: although the difference of the Airalready heated, both in _hot Countries_, and in the _Planets_, that areneerer than we, may alter, if not the quantity of Light, at least that ofthe Heat, found there. * * * * * _A further Account, touching Signor _Campani_'s Book and Performances about_Optick-glasses_. _ In the above-mentioned _French_ Tract there is also conteined M. _Auzout's_Opinion of what he had found New in the _Treatise_ of Signor _Campani_, which was spoken of in the first _Papers_ of these _Transactions_, concerning both the Effect of the _Telescopes_, contrived after a peculiarway by the said _Campani_ at _Rome_, and {71} his New Observations of_Saturn_ and _Jupiter_, made by means thereof. First therefore, after that M _Auzout_ had raised some scruple against theContrivance of Signor _Campani_ for making _Great Optick-Glasses_ without_Moulds_, by the means of a _Turn-lath_, he examines the _Observations_, made with such _Glasses_: Where, having commended _Campani_'s sincerity inrelating what he thought to have seen in _Saturn_, without accomodating itto M. _Hugens_'s _Hypothesis_, he affirms, that supposing, there be a_Ring_ about _Saturn_, Signor _Campani_ could not see in all thosedifferent times, that he observed it, _the same Appearances_, which henotes to have _actually_ seen. For, having seen it sometimes in _TrineAspect_ with the _Sun_, and _Oriental_; sometimes, in the same _Aspect_, but _Occidental_; sometimes in _Sextil Aspect_, and _Occidental_; atanother time, again in _Trine_, and _Oriental_, this Author cannotconceive, how _Saturn_ could in all these different times have nodifference in its _Phasis_, or keep always the same _Shadow_; seeing that, according to the _Hypothesis_ of the _Ring_, when it was _Oriental_, itmust cast the _Shadow_ upon the _left_ side of the _Ring_ beneath, withoutcasting any on the _right_ side: and when it was _Occidental_, it could notbut cast it on the _right_ side beneath, and nothing of it on the other. Concerning the _Shadow above_, which _Campani_ affirms to be made by the_Ring_ upon the Body of _Saturn_, M. _Auzout_ judges, that there could beno such _Phænomenon_, by reason of its _Northern Latitude_ at the times, wherein the _Observations_ were made, _vid. _ in _April_ 1663; in the midstof _August_, and the beginning of _October_, next following, and in _April_1664, except it were in _October_, and the _Shadow_ strong enough to become_visible_. But as to the _Shadow below_, he agrees with _Campani_, that it doesappear, yet not as he notes it, seeing that it must be sometimes on the oneside, sometimes on the other; and towards the _Quadrat_ with the _Sun_ itmust appear biggest, as _indeed_ he affirms to have seen it himself _this_year, insomuch that sometimes it seemed to him, that it covered the whole_Ring_, and that the _Shadow_, joyning with the obscure space between both, did interrupt the circumference of the _Ring_; but beholding it at othertimes in a cleer Sky, and when there was no Trepidation of the Air, {72} hethought, that he saw also the Light continued from without, although veryslender. But he acknowledges, that he could never yet _precisely_determine, by how much the largeness of the _Ring_ was bigger than the_Diameter_ of _Saturn's_ Body. As for the proportion of the Length to theBreadth, he affirms, to have alwaies estimated it to be two and a half, orvery neer so; and to have found in his _Observations_, that in _January_last, one time, the length of _Saturn_ was 12 _Lines_, and the breadth 5. Another time, the length was 12. _Lines_, and the breadth 4. And this by apeculiar method of his own. But yet he acknowleges also, that sometimes hehath estimated it as 7. To 3. And at other times as 13. To 5. And that ifthere do not happen a change in the magnitude of the _Ring_ (as it is notlikely there does) that must needs proceed from the Constitution of theair, or of the Glass's having more or less _Aperture_, or from thedifficulty of making an exact estimate of their proportions. However it isnot much wide (saith he) of two and a half, although _Campani_ make thelength of the _Ring_ but double to its breadth. Monsieur _Auzout_ believes, that he was one of the first that have wellobserved this shadow of _Saturn's_ Body upon its _Rings_ which he affirmshappened two years since; when, observing in _July_, for the first time, with a _Telescope_ of 21. And then another of 27. Foot, he perceived, thatthe _Angle_ of the obscure space on the _right side_ beneath, was biggerand wider, than the three other _Angles_, and that some interruptionappear'd _there_, between the _Ring_, and the _Body of Saturn_; of which hesaith to have given notice from that time to all his friends, and inparticular, as soon as conveniently he could, to Monsieur _Hugens_. He confesseth, that he hath not had the opportunity of observing _Saturn_in his _Oriental Quadrat_; yet he doubts not, but that the _shadow_ appearson the _Left-side_, considering, that the _Existence_ of the _Ring_ can beno longer doubted of, after so many _Observations_ of the _shadow_ cast by_Saturn's_ Body upon it, according as it must happen, following that_Hypothesis_; there being no reason, why it should cast the said _shadow_on one side, and not on the other. Concerning the Observation of _Jupiter_ and its _satellites_, the famous_Astronomer_ of _Bononia_, _Cassinus_, having {73} published, that on the30. Day of _July_, 1664. At 2½ of the clock in the morning, he hadobserv'd, with _Campani_'s Glasses, that there passed through the broadobscure _Belt_ of _Jupiter_ two obscurer _spots_, by him esteemed to be the_shadows_ of the _Satellites_, moving between _Jupiter_ & the _Sun_, andeclipsing him, and emerging from the Occidental Brim thereof: This_Authour_ did first conceive, that they were not _shadows_, but some_Sallies_, or _Prominencies_ in that _Belt_; which he was induced tobelieve, because he perceived not, that that _Prominency_, which he theresaw, was so black, nor so round as _Cassini_ had represented his _spots_;wherefore, seeing it but little differing in colour, from the _Belt_, andso not judging it round, because it did stand only about half its diameterout of the _Belt_, he persuaded himself, that it was rather a _Sally_, or_Prominency_ of the _Belt_, than a round _shadow_, as that of a _Satellite_of _Jupiter_ must have bin. But having been since informed of _all_ the_Observations_ made by _Cassini_ and _Campani_, with the _New_ Glasses, andseen his _Figure_, he candidly and publickly wisheth, that he had notspoken of that _Sally_, or _Prominency_; advowing that he can doubt nolonger, but that it was the _shadow_ of the _Satellit_ between _Jupiter_and the _Sun_, having seen the other emerge, as soon as with a 20. FootGlass he made the Observation, and having not perceiv'd these _shadows_with a 12. Foot Glass: But although he grants that they did ghess betterthan he, yet he doth it with this _proviso_, _vid. _ in case they made_that_ Observation on of _July_ 30. Not with their 36. But 12. Or 17. Foot_Telescope_. If it be wondred at, that Monsieur _Auzout_ did not see this_shadow_ move, he allegeth his indisposition for making _longObservations_, and addeth, that it may be much more wondred at, thatneither _Campani_ nor himself did see upon the obscure _Belt_ the Bodies ofthe _Satellites_, as parts more Luminous than the _Belt_. For (saith he)although the _Latitude_ was _Meridional_, it being no more than of 9. Or10. Minutes, the Body of the _Satellites_ should, thinks he, pass between_us_ and the _Belt_, especially according to _Campani_, who maketh the_Belt_ so large, and puts the _shadows_ farr enough within the same. Thismaketh him conclude, that either they have not observed well enough, orthat the motion of the _Satellites_ doth not exactly follow the _Belts_, and is inclin'd unto them. Whereupon he resolves, that when he shall knowthat they are to pass between _Jupiter_ and _us_, and to be over againstthe _Belt_, that {74} then he will observe, whether he can see them appearupon the _Belt_, as upon a darker ground, especially, the _third_ of them, which is sensibly greater, and more Luminous, than the rest. He hopethalso, that in time, the _shadow_ of _Saturns Moon_ will be seen upon_Saturn_, although we are yet some years to stay for it, and to preparealso for better Glasses. From this rare Observation, he inferrs the _Proportion_ of the _Diameter_of the _Satellites_ to that of _Jupiter_; and judgeth, that no longer doubtcan be made of the turning of these 4. _Satellites_, or _Moons_ about_Jupiter_, as our _Moon_ turns about the _Earth_, and after the same way asthe rest of the Celestial Bodies of our _Systeme_ do move: whence also astrong conjecture may be made, that _Saturns_ Moon turns likewise about_Saturn_. Hence he also taketh occasion to intimate, that we need not scruple toconclude, that if these two _Planets_ have _Moons_ wheeling about them, asour _Earth_ hath one that moves about it, the conformity of these _Moons_with our _Moon_, does prove the conformity of our _Earth_ with those_Planets_, which carrying away their _Moons_ with themselves, do turn aboutthe _Sun_, and very probably make their _Moons_ turn about them in turningthemselves about their _Axis_; and also, that there is no cause to inventperplex'd and incredible _Hypotheses_, for the receding from this_Analogie_ since (saith he) if this be truth, the Prohibitions ofpublishing this doctrine, which formerly were caused by the offence ofNovelty, will be laid aside, as one of the most zealous Doctors of thecontrary Opinion hath given cause to hope, witness _Eustachius de Divinis_, in his _Tract_ against Monsieur _Hugen_'s _Systeme_ of _Saturn_, _p. _ 49. Where we are inform'd, that that learned Jesuit, _P. Fabry_, Penitentiaryof S _Peter_ in _Rome_, speaks to this purpose: Ex vestris, iisque Coryphæis non semel quæsitum est, utrum aliquam haberentdemonstrationem pro _Terræ motu_ adstruendo. Nunquam ausi sunt id asserereNul igitur obstat quin loca illa in sensu literali Ecclesia intelligat, &intelligenda esse declaret, quamdiu nulla demonstratione contrariumevincitur; quæ si forte aliquando a vobis excogitetur (quod vix crediderim)in hoc casu nullo modo dubitabit Ecclesia declarare, loca illa in sensufigurato & improprio intelligenda esse, ut illud Poetæ, _Terræque Urbesquerecedunt_. _It hath been more than once asked of your Chieftains, whether they had aDemonstration for asserting the motion of the Earth? They durst never yetaffirm they had; wherefore nothing hinders, but that the Church mayunderstand those Scripture-places, that speak of this matter, in a_literal_ sence, and declare they should be so understood, as long as thecontrary is not evinced by any demonstration; {75} which, if perhaps itshould be found out by you (which I can hardly believe it wil) in this casethe Church will not at all scruple to declare, that these places are to beunderstood in a figurative and improper sence, according to that of thePoet, _Terræque Urbesque recedunt_. _ Whence this Author concludes, that the said _Jesuite_ assuring us that the_inquisition_ hath not _absolutely_ declared, that those Scripture-placesare to be understood _literally_, seeing that the _Church_ may make acontrary declaration, no man ought to scruple to follow the _Hypothesis_ ofthe _Earths motion_, but only forbear to maintain it in _publick_, till theprohibition be called in. But to return to the matter in hand, this Author, upon all these observations and relations of _Cassini_ and _Campani_, dothfind no reason to doubt any more of the excellency of the Glass used bythem, above his; except this difference may be imputed to that of the_Air_, or of the _Eys_. But yet he is rather inclined to ascribe it to thegoodness of their Glasses, and that the rather, because, he would not bethought to have the vanity of magnifying his own; of which, yet heintimates by the by, that he caused one to be wrought, of 150 _Parisian_feet; which though it proved none of the best, yet he despairs not to makegood ones of _that_, and of far greater Length. * * * * * __Signor Campani's_ Answer: and Monsieur _Auzout_'s Animadversionsthereon. _ The other part of this _French Tract_, conteining _Campani_'s Answer, andMr. _Auzout_ his _Reflections_ thereon, begins with the pretended _Shadows_of the _Ring_ upon _Saturn_, and of _Saturn_ upon the _Ring_. Concerningwhich, the said _Campani_ declareth, that he never believed them to be_shadows_, made by the _Ring_ upon the _Disk_ of _Saturn_, or by the bodyof _Saturn_ upon the _Ring_, but the _Rimms_ of these bodies, which being_unequally_ Luminous, did shew these appearances. In which Explication, forasmuch as it represents, that the said _Campani_ meant to note only the_Inequality of the Light_, which, _he saith_, his Glasses did discover, Mr. _Auzout_ does {76} so far acquiesce, that he only wishes, that his ownGlasses would shew him those differences. Next to the Objection, made byMonsieur _Auzout_, against Signor _Campani_, touching the Proportion of theLength of the _Ring_ to its breadth, _Campani_ replyeth, that the Glassesof Monsieur _Auzout_, shew not all the particulars, that his do, andtherefore are unfit for determining the true Figure and breadth of theapparent _Ellipsis_ of the _Ring_. To which M. _Auzout_ rejoyns, that he isdispleased at his being destitute of better Glasses, but that it will bevery hard for the future to convince _Campani_ touching the _Proportion_ ofthe _Ring_, seing that the breadth of the _Ellipsis_ is always diminishing, although, if the declination of the _Ring_ remains always the same, one canat all times know, which may have been its greatest breadth. But heassures, that the breadth of the _Ring_ is not the half of its length, andthat it doth not spread out so much beyond _Saturn_'s Body, as he hathalleged. And withal desirs to know, what can be answered by Sig. _Campani_to M. _Hugens_, who being persuaded, that the Declination of the _Ring_ isnot above 23 deg. 30' having seen the _Ring_ to spread out above the Bodyof _Saturn_, concludes, in a Letter to M. _Auzout_, that the length of the_Ring_ is more than treble the _Diameter_ of _Saturn_'s body, which, according to _Campani_, is only as about 67 to 31. Which difference yet dosnot appear to M. _Auzout_ to be so great; but that M. _Hugens_ perhaps willimpute it to the Optical reason, which he (_Auzout_) hath alleged of theAdvance of the light upon the obscure space; although he is of Opinion, heshould not have concluded so great a Length, if he had not seen the Breadthspread out more, than he hath done: for (_saith he_) if the Length of the_Ring_ be to the body of _Saturn_, 2½ to 1. And the _Inclination_ be 23deg. 30' the _Ring_ will be just as large, as the body, without spreadingout; but if the _Ring_ be bigger, it will a little spread out; and if itwere treble, it must needs spread out the half of its breadth, which hathnot so appeared to him. Further, to M. _Auzout's_ change of Opinion, and believing, that the_Advance_ or _Sally_, seen by him in _Jupiter_, was the _Shadow_ of one ofhis Moons, _Campani_ declares, that he would not have him guilty of thatchange: Whereupon M. _Auzout_ wonders, why _Campani_ then hath not markedit in his _Figure_; and would {77} gladly know, whether that _Sally_ bemore easie to discover, than the _Shadows_ of the _Satellites_, which_Campani_ believs, _Auzout_ hath not seen; and whether he be assured, thatthose obscure parts, which he there distinguishes, do not change: for ifthey should not change, then _Jupiter_ would not turn about his _Axis_, which yet, he saith, it doth, according to the _Observation_ made by Mr. _Hook_, _May_ 9 1664. Inserted in the first papers of these _Transactions_. The full Discovery of which particular also he makes to be a part of_Cassini's_ and _Campani_'s work, seeing that they so distinctly see theinequalities in the _Belts_, and see also sometimes other _Spots_ besidesthe _Shadows_ of the _Satellites_: where he exhorts all the Curious, thathave the conveniency of observing, to endeavor the discovery of a matter ofthat importance, which would prove one of the greatest _Analogies_ for the_Earth's Motion_. * * * * * _An Account of Mr. _Richard Lower_'s newly published _Vindication_ ofDoctor _Willis_'s _Diatriba_ de _Febribus_. _ The Title of this Curious piece, is _Diatribæ Thomæ Willisii Med. Doct. &Profess. Oxon. De Febribus Vindicatio, Authore Richardo Lower, &c. _ In itare occasionally discussed many considerable Medical and Anatomicalinquiries, as, Whether a Fever does consist in an Effervescence of Blood?And if so, of what kind? Whether there be a _Nervous_ and _Nutritious_Juice? Whether the office of sanguification belongs to the Blood it self, existing _before_ those _Viscera_ (at least) that are commonly esteemed tobe the Organs of sanguification? How _Nutrition_ is performed, and thenourishing substance assimilated? Whether the Blood affords both the Matterfor the structure of the Body, and such parts also, as are fit for thenourishment of the same? Whether the Pulse of the Heart ceasing, thereremains yet a certain Motion in the blood, arguing, that _Pulse_ and _Life_do ultimately rest in the _Blood_? Whether the Umbilical Vessels convey theblood of the Mother to the Child, or whether the _Foetus_ be for the mostpart form'd and {78} acted by the circulating blood, before the existenceof the Umbilical Vessels, or before the connecting of the _Foetus_ with the_Uterus_? A new Experiment to prove that the _Chyle_ is not transmuted into_Blood_ by the _Liver_. A discourse of the Nature of the _Blood_, and whatdifference there is between the _Venal_ and _Arterial_ blood, and for whatUses both the one and the other are particularly designed. Where it isconsidered, what _Life_ is, and whence the _Soul_ of _Brutes_, and itssubsistence, and operations do depend. It is also inquired into, what theuses of the _Lungs_ are in _hot_ Animals? And many other such materialdisquisitions are to be found in this small, but very Ingenious and LearnedTreatise. * * * * * _A Note touching a Relation, inserted in the last _Transactions_. _ In the Experiment of killing _Ratle-Snakes_, mentioned in the last of theprecedent Papers (wherein, by a mistake, these words, _The way_, were putfor _A way_, or _An Experiment_) it should have been added, that theGentleman there mention'd, did affirm, that, in those places, where theWild _Penny-Royal_ or _Dittany_ grows, no _Ratle-Snakes_ are observed tocome. * * * * * _Errata. _ Pag. 59. Line 11. Read, _bignesses_, l. 20. R. _endure_, for, resist. L. 30. R. _those_, for, these. L. 31. R. _Plain_, for, place. * * * * * _LONDON, _ Printed with Licence, By _John Martyn_, and _James Allestry_, Printers tothe _Royal-Society_, at the _Bell_ in St. _Pauls Church-Yard_. 1665. {79} * * * * * _Numb. _ 5. PHILOSOPHICAL_TRANSACTIONS. _ * * * * * _Munday_, _July_ 3. 1665. * * * * * The Contents. _An Account, how _Adits_ and _Mines_ are wrought at _Liege_ without _Air-shafts_, communicated by Sir _Robert Moray_. A way to break _easily_ and _speedily_ the hardest _Rocks_; imparted by the same _Person_, as he received it from Monsieur _Du Son_ the Inventor. Observables upon a _Monstrous Head_. Observables in the Body of the Earl of _Belcarres_, sent out of _Scotland_. A Relation of the designed Progress to be made in the _Breeding of Silk-worms_, and the _Making_ of _Silk_, in _France_. Enquiries touching _Agriculture_, for _Arable_ and _Meadows_. _ * * * * * _An Account, how _Adits_ & _Mines_ are wrought at _Liege_ without_Air-shafts_, communicated by Sir _Robert Moray_. _ It is well known to those conversant in _Mines_, that there is nothing ofgreater inconvenience in the working or _driving_, as they call it, of_Mines_ or _Adits_ under ground, for carrying away of Water, or such_Minerals_ as the _Mine_ affords, than the _Damp, want, _ and _impurity ofAir, _ that {80} occur, when such _Adits_ are wrought or driven inward upona _Level_, or near it, 20, 30, or 40. Fathom, more or less. Aswel becauseof the expence of money, as of time also, in the _Ordinary_ way ofpreventing or remedying those inconveniences; which is, by letting down_shafts_ from the _day_ (as _Miners_ speak) to meet with the _Adit_; bywhich means the Air hath liberty to play through the whole work, and sotakes away bad vapours and furnishes good Air for Respiration. The Expenceof which _shafts_, in regard of their vast depth, hardness of the Rock, drawing of water, &c. Doth sometimes equal, yea exceed the _ordinary_charge of the whole _Adit_. Amongst the _Expedients_ that have been devised to remedy this, there isone practised in the _Coal-mines_, near the Town of _Liege_ (or _Luyck_)that seems preferable to all others for Efficacy, Ease, and Cheapness: thedescription whereof followeth. At the mouth or entry of the _Adit_ there is a structure raised of _Brick_, like a _Chimney_, some 28. Or 30. Foot high in all: at the bottom, twoopposite sides are (or may be) some 5½ foot broad; and the other two, 5. Foot: the wall 1½ _Brick_ thick. At the lower part of it, is a hole, some9. Or 10. Inches square, for taking out of the Ashes, which when it isdone, this Ash-hole is immediately stopt so close, as Air cannot possiblyget in at any part of it. Then, some 3. Foot above ground or more, there ison that side, that is next to the _Adit_ or Pit, a square hole of 8. Or 9. Inches every way, by which the Air enters to make the Fire burn: Into thishole there is fixed a square _Tube_ or _Pipe_ of Wood, whereof the Jointsand Chinks are so stopt with Parchment pasted or glewed upon them, that theAir can no where get in to the Pipe but at the end: And this Pipe is stilllengthened, as the _Adit_ or Pit advanceth, by fitting the new Pipes so, asone end is alwaies thrust into the other, and the Joints and Chinks stillcarefully cemented and stopt as before. So the Pipe or Tube being stillcarried on, as near as is necessary, to the wall or place, where fresh Airis requisite; the Fire within the Chimney doth still attract {81} (so tospeak) Air through the Tube, without which it cannot burn, which yet itwill do, as is obvious to conceive (all Illustrations and PhilosophicalExplications being here superfluous, ) and so, while the Air is drawn by thefire from the farthest or most inward part of the _Mine_ or _Adit_, freshAir must needs come in from without to supply the place of the other, whichby its motion doth carry away with it all the ill vapors, that breath outof the ground; by which meanes the whole _Adit_ will be alwaies filled withfresh Air, so that men will there breath as surely as abroad, and not onlyCandles burn, but Fire, when upon occasion there is use for it for breakingof the Rock. Now that there may be no want of such fresh Air, the Fire must alwaies bekept burning in the Chimney, or at least as frequently as is necessary: Forwhich purpose there must be two of the Iron Grates or Chimneys, that whenany accident befals the one, the other may be ready to be in its place, theCoals being first well kindled in it: but when the fire is neer spent, theChimney or Grate being haled up to the dore, is to be supplied with freshfuel. The Figure of the Fabrick, Chimney, and all the parts thereof beinghereunto annexed, the rest will be easily understood. [Illustration] _Figure_ 1. A. The _Hole_ for taking out the Ashes. B. The _Square-hole_, into which the Tube or Pipe for conveying the Air isto be fixed. C. The _Border_ or _Ledge_ of _Brick_ or _Iron_, upon which the_Iron-grate_ or _Cradle_, that holds the burning Coals, is to rest, the onebeing exactly fitted for the other. D. The _Hole_ where the _Cradle_ is set. E. The woodden _Tube_, through which the Air is conveyed towards the_Cradle_. F. The _Dore_, by which the _Grate_ and _Cradle_ is let in, which is {82}to be set 8. Or 10. Foot higher than the Hole D. And the _Shutter_ made ofIron, or Wood that will not shrink, that it may shut very close, this_Dore_ being made large enough to receive the _Cradle_ with ease. G. The _Grate_ or _Cradle_, which is narrower below than above, that theAshes may the more easily fall, and the Air excite the Fire; the bottombeing barred as the sides. H. The _Border_ or _Ledge_ of the _Cradle_, that rests upon the _Ledge_ C. I. Four _Chains_ of _Iron_ fastned to the four corners of the _Cradle_, fortaking of it up, and letting of it down. K. The _Chain_ of _Iron_, to which the other are fastned. L. The _Pulley_ of _Iron_ or _Brass_, through which the _Chain_ passeth. M. A _Hook_, on which the end of the _Chain_ is fastned by a _Ring_, the_Hook_ fixed being placed in the side of the Dore. N. A _Barr_ of _Iron_ in the Walls, to which the _Pulley_ is fastned. The higher the _Shaft_ of the Chimney is, the Fire draws the Air thebetter. And this Invention may be made use of in the _Pits_ or _Shafts_, that are _Perpendicular_, or any wise inclining towards it, when there iswant of fresh Air at the bottom thereof, or any molestation by unwholsomFumes or Vapors: * * * * * _A way to break _easily_ and _speedily_ the hardest _Rocks_, communicatedby the same Person, as he received it from Monsieur _Du Son_, theInventor. _ [Illustration] Though the invention of breaking with ease, and dispatch, hard Rocks, maybe useful on several occasions, the benefit is incomparably great, that maythereby accrue to those, who have _Adits_ or Passages to cut through hard_Rocks_, for making passage for Water to run out by, in _Mines_ of _Lead_, _Tin_, or any other whatsoever; these _Adits_ appearing to be the surest, cheapest, and most advantagious way imaginable, for draining of the same. {83} That which is here to be described, was invented by one of the mostExcellent _Mechanicks_ in the World, _Monsieur du Son_, who lately put itin practice himself in _Germany_, at the desire of the _Elector_ of_Mentz_. The manner is, as followeth. The _Mine_ or _Adit_ is to be made seven or eight foot high, which thoughit seem to make more work downwards, yet will be found necessary for makingthe better dispatch by rendring the Invention more effectual. There is a _Tool_ or _Iron_ well steeled at the end, which cuts the Rock, (of the shape shewed by _Fig. _ 2. Here annexed, ) 20. Or 22. Inches long ormore, and some 2½ Inches _Diameter_ at the steeled end, the rest beingsomewhat more slender. The steeled end is so shaped, as makes it most aptto pierce the Rock, the Angles at that end being still to be made the moreobtuse, the harder the Rock is. This _Tool_ is to be first held by thehand, in the place, where the Hole, to be made for the use, which shallhere be shewed, is to be placed; that is, in the middle between the sidesof the Rock, that is to be cut, but as near the bottom as may be. The_Tool_ being placed, is to be struck upon with an Hammer, the heavier thebetter, either suspended by a Shaft turning upon a Pin, or otherwise, so asone man may manage the Hammer, while another holds the Tool or Piercer. Ifit be hung in a _Frame_, or other convenient way, he that manageth it hathno more to do, but to pull it up at first as high as he can, and let itfall again by its own weight, the motion being so directed, as to be sureto hit the Piercer right. After the stroke of the Hammer, he that holds thePiercer, is to turn it a little on its point; so that the Edges or Anglesat the point may all strike upon a new place; and so it must still beshifted after every stroke, by which means small Chipps will at everystroke be broken off, which must from time to time be taken out, as needrequires. And thus the work must be continued, till the _Hole_ be 18. Or20. Inches deep, the deeper the better. This _Hole_ being made as deep asis required, and kept as streight and smooth in the sides, as is possible, there is then a kind of double _Wedge_ to be made, and {84} fitted exactlyfor it; the shape whereof is to be seen in the annexed 3. Figure. [Illustration] This double _Wedge_, being 12. Or 13. Inches long, each piece of it, and somade, as being placed in their due position they may make up a _Cylinder_, but _Diagonal_-wise. The two flat sides that are contiguous, are to begreased or oyled, that the one may slip the more easily upon the other; andone of them, which is to be uppermost, having at the great end a hollow_Crease_ cut into it round about, for fastening a _Cartridge_, full of_Gunpowder_, to it with a thred, the round end of the _Wedge_ being paredas much as the thickness of the Paper or Pastboard, that holds the Powder, needs to make the outside thereof _even_ with the rest of the _Wedge_. This_Wedge_ must have an Hole drilled through the longest side of it, to befilled with _priming Powder_, for firing of the Powder in the _Cartridge_;which needs have no more, than half a pound of Powder, though upon occasiona greater quantity may be used, as shall be found requisite. Then this _Wedge_, being first thrust into the Hole with the _Cartridge_, the round side, whether the Priming-hole is, being uppermost, the other_Wedge_ is to be thrust in, home to the due position, care being taken, that they fit the Hole in the Rock as exactly as may be. Then the end ofthe lower _Wedge_ being about an Inch longer, than that of the upperoutwardly, and flatned, priming Powder is to be laid upon it; and a pieceof burning _Match_ or _Thread_ dipt in _Brimstone_ or other such preparedcombustible Matter, fastned to it, that may burn so long before it fire thePowder, as he, that orders it, may have time enough to retire quite out thePit or _Adit_, having first placed a piece of Wood or Iron so, as one endthereof, being set against the end of the lower Wedge, and the otheragainst the side-wall, so as it cannot slip. Which being done, and the Manretired, when the Powder comes to take fire, it will first drive out theuppermost Wedge, as far as it will go, but the slaunting figure of it beingso made, as the farther it goes backward, the thicker it grows, till at thelast it can go no farther, then the {85} fire tears the Rock to get forth, and so cracks and breaks it all about, that at one time a vast deal of itwill either be quite blown out, or so crackt and broken, as will make iteasie to be remov'd: And according to the effect of one such _Cartridge_, more may be afterwards made use of, as hath been said. * * * * * _Observables upon a _Monstrous Head_. _ [Illustration] This was the Head of a _Colt_, represented in the annexed _Figure_ 4. Firstviewed by Mr. _Boyle_, who went into the Stable where the _Colt_ lay, andgot the Head hastily and rudely cut off, the _Body_ thereof appearing tohis Eye compleately formed, without any _Monstrosity_ to be taken notice ofin it. Afterwards he caused it to be put into a Vessel, and covered with_Spirit of Wine_ thereby chiefly intending, to give good example, togetherwith a proof, that by the help of the said _Spirit_, (which he hathrecommended for such Properties in one of his _Essays_ of the _Usefulness_of _Natural Philosophy_) the parts of _Animals_, and even _Monsters_, mayin _Summer_ it self be preserved long enough to afford _Anatomists_ theopportunities of examining them. The Head being opened, and examined, it was found. _First_, That it had no sign of any _Nose_ in the usual place, nor had itany, in any other place of the Head, unless the double Bag CC, that grewout of the midst of the forehead, were some rudiment of it. _Next_, That the _two Eyes_ were united into one _Double Eye_, which wasplaced just in the middle of the Brow, the Nose being wanting, which shouldhave separated them, whereby the two Eye-holes in the Scull were unitedinto one very large round hole, into the midst of which, from the Brain, entred one pretty large _Optik Nerve_, at the end of which grew a great_Double Eye_; that is, that _Membrane_, called _Sclerotis_, which containedboth, was one and the same, but seemed to have a _Seam_, {86} by which theywere joined, to go quite round it, and the fore or pellucid part wasdistinctly separated into two _Cornea_'s by a white _Seam_ that dividedthem. Each _Cornea_ seemed to have its _Iris_, (or Rain-bow-like Circle)and Apertures or Pupils distinct; and upon opening the _Cornea_, there wasfound within it two _Balls_, or _Crystalline Humours_, very well shaped;but the other parts of it could not be so well distinguished, because theeye had been much bruised by the handling, and the inner parts confused anddislocated. It had four Eye-browes, placed in the manner exprest in Figure4. By a a, b b; a a representing the _lower_, and b b, the _upper_Eye-lids. _Lastly_, That just above the Eyes, as it were in the midst of theForehead, was a very deep depression, and out of the midst of that grew akind of double _Purse_ or _Bagg_, C C, containing little or nothing in it;but to some it seemed to be a production of the matter designed for theNose, but diverted by this Monstrous Conception; perhaps the _Processusmammillares_ joyned into one, and covered with a thin hairy skin. * * * * * _Observables in the Body of the _Earl_ of _Balcarres_. _ These following Observations, were a while since sent out of _Scotland_ byan ingenious person, an Eye-witness, to Sir _Robert Moray_. 1. That the Belly of this Nobleman being opened, the _Omentum_ or _Net_ wasfound lean and small: his _Liver_ very big; the _Spleen_ big also, filledwith a black and thick humour. His _Stomack_ and _Entralls_ all empty, of aSaffron-colour, distended with wind only. The _Bladder_ of _Gall_ swelledwith a black humour: The _Kidneys_ filled with a kind of _grumous blood_. 2. That in the _Thorax_ or _Chest_, the _Lobes_ of the _Lungs_ were allentire, but of a bad colour; on the left side somewhat black and blue, andon the right, whitish; with a yellowish knob under one of the _Lobes_. {87} 3. That the _Pericardium_ or the _Case_ of the _Heart_ being opened, thereappeared none of that water, in which the _Heart_ uses to swim; and theexternal Surface of it, from the _Base_ to the _Tipp_, was not smooth, butvery rough. It being cut asunder, a quantity of white and inspissateliquour run out, and beneath the _Base_, between the right and leftVentricle, _two stones_ were found, whereof the one was as bigg as an_Almond_, the other, _two_ Inches long and _one_ broad, having three_Auricles_ or crisped _Angles_: And in the Orifice of the right Ventricle, there was a fleshy fattish Matter. 4. That the whole Body was bloudless, thin, and emaciated, of a black andbluish Colour. 5. The _Scull_ being opened, both the _Cerebrum_ and _Cerebellum_ were biggin proportion to the Body; and out of it run much more Bloud, than was seenin both the other Regions together. * * * * * _Of the designed Progress to be made in the _Breeding of Silkworms_, andthe _Making_ of _Silk_, in _France_. _ The _French_ King _Henry the Fourth_, having made a general Establishmentall over _France_, of planting and propagating of _Mulberry-trees_, and_Breeding of Silkworms_, in order to set up and entertain a _Silk-trade_there; and having prospered so well in that Design, that in many parts ofhis Dominions great store of such Trees were raised, and Multitudes ofSilk-works propagated, to the great benefit of the _French_ people, forasmuch as it was a considerable beginning to avoid the transport ofseveral Millions abroad for buying of Silks, and withall an excellent meansof well-imploying abundance of poor Orphans and Widows, and many old, lame, and other indigent and helpless people; The present _French King_, hathlately revived and seconded that Undertaking by giving express order thatit should be promoted by all possible means, and particularly in the_Metropolis_ of that Kingdom, and round about it; and that for that end thewhole way concerning that Work and {88} Trade should be fully andpunctually communicated in Print; which hath also been executed by one_Monsieur Isnard_, in a Treatise published at _Paris_, in _French_, Intituled, _Instructions for the Planting of White Mulberryes, the Breedingof Silkworms, and the Ordering of Silk in _Paris_, and the circumjacentPlaces_, In which Book, the Method being represented, which that GreatPrince _Henry_ IV used in establishing the said Work and Trade, togetherwith the success thereof, and the advantages thence derived to hisSubjects, the _Author_, from his own _Experience_, and long _Practice_, delivers (and seems to do it candidly) all what belongs in this business infour main heads. _First_, he teaches the Means of sowing, planting, andraising _White Mulberryes_ (as the Foundation of Silkworks) shewing howmany several wayes _that_ may be done. _Secondly_, The Breeding of_Silkworms_, the choosing of good Eggs, and their hatching, as also theFeeding of the _Worms_, and preserving them from sickness, and Curing themof it, together with the way of making them spin to best advantage. _Thirdly_, The manner of winding their Silk from their Bottoms, adding the_Scheme_ of the _Instrument_ serving for that purpose. _Fourthly_, The wayof _keeping_ _Silkworms_ Eggs for the ensuing year. Through the whole Book are scattered many not inconsiderable particulars, though perhaps known to most. The _White Mulberry Tree_, as it is in otherqualities preferable to the _Black_, so this _Author_ esteems it the best, not only for the durableness of the wood, and its large extent ofusefulness in Carpentry and Joyners work; but also for the fitness of itsleaves (besides their principal use for the food of _Silkworms_) to fattenSheep, Goats, Cowes, and Hoggs, only by boyling and mingling them withBran. The Berryes themselves he commends as very excellent to fattenPoultry, and to make them lay Eggs plentifully. In the _Changes_, _Working_, and _Generation_ of this _Insect_, he is very curious to observemany things. Their _Metamorphoses_, as is known, are four, whereof the formof the one hath no conformity with any of the rest. The first from an Egge(of the bigness of a Mustard-seed, and of a darkish Gray Colour, when good)to a _Worm_ or _Caterpillar_, but of a domestick, noble, and profitablekind, _Black_, when it first comes {89} forth, but growing _white_ at last;having 24. Feet, 8. On each side of the body, and 4. Besides, close to eachside of the head. During this form, they undergo constantly 4. Sicknesses, in which they cast their Skins, each sickness lasting about 4. Days, wherein they feed not at all; but grow clearer, shorter, and thicker. Thesecond from a _Worm_ to an _Aurelia_ or _Chrysalis_, having the shape of asmall Plum, whereunto it is transformed after its spinning time is past; inwhich state it lies shut up, in hot Countries, for 14. Or 15. Dayes; inmore temperate ones, 18. Or 20. Without any Food or Air, known to us. During which time this _Insect_ leaves two Coats, both that of a _Worm_, whence 'tis changed into an _Aurelia_, and that of an _Aurelia_, whence itbecomes a _Papilio_ or _Butterfly_, in the _Theca_ or _Case_. The third is, from an _Aurelia_ to a _Butterfly_, coming out of the _Theca_ with a head, leggs, and horns; for which passage it makes way by a whitish water, itcasts upon the Silk, which moistning, and thereby in a manner putrefyingit, the new creature thrusts out its head through the sharp end of the_Case_, by a Hole as big as its self. There is found no Excrement in the_Case_, but the two Skins only, just now mentioned. Before they begin to spin, and about the latter end of their feeding, theymust, saith the _Author_, be often changed, and have Air enough, by openingthe Windows of the Room, they are in, if it be not too ill Weather; else, saith he, the Silk that is in their Belly, will cause so extraordinary aheat in them, that it burns their gutts, and sometimes bursts them; and thesame (being a substance that resembleth Gum or Burgundy Pitch) will putrefyand turn into a yellowish matter. He maketh the best marks of their maturity for spinning to be, when theybegin to quit their white Colour, & their green and yellow Circles, andgrow of the Colour of Flesh, especially upon the tail; having a kind of_consistent_ softness shewing that they have something substantial in theirStomachs. As for their _Working_, he gives this account of it, that the first daythey make only a _Webb_; the second, they form in this _Webb_ their_Cases_, and cover themselves all over with Silk; the third day, they areno longer seen, and the dayes following they thicken their _Cases_, alwayesby one _end_ or _thread_, which they {90} never break off, themselves. This, he affirms, they put out with so much quickness, and draw it sosubtle and so long, that without an _Hyperbole_, the _end_ or _thread_ ofevery _Case_ may have two Leagues in length. He advertiseth, that they mustbe by no means interrupted in their work, to the end, that all the Silk, they have in their bellyes, may come out. Some eight dayes after they have finished their Work, as many of the best_Cases_, as are to serve for _seed_, _viz. _ the first done the hardest, thereddest and best coloured, must be chosen, and put a-part; and alldiligence is to be used to winde off the silk with as much speed, as maybe, especially if the _Worms_ have nimbly dispatched their work. Here he spends a good part of his Book, in giving very particularInstructions, concerning the way of winding off the silk, setting also downthe form of the Oven and Instruments necessary for that work, which is thepainfullest and nicest of all the rest. Touching their _Generation_, he prescribeth that there be chosen as manymale as female _Cases_ (which are discerned by this, that the males aremore pointed at both ends of the _Cases_, and the females more obtuse onthe ends, and bigger-bellyed) and that care be had, that no _Cases_ betaken, but such wherein the _Worms_ are heard rolling; which done, and theybeing come forth in the form of _Butterflies_, having four wings, six feet, two horns, and two very black eyes, and put in a convenient place, themales fluttering with their wings, will joyn and couple with the females, after that these have first purged themselves of a kind of reddish humourby the fundament: in which posture they are to be left from Morning (whichis the ordinary time of their coming forth) till evening, and then thefemales are to be gently pulled away, whereupon they will lay their eggs, having first let fall by the Fundament another humour, esteemed to proceedfrom the seed of the males; but the males are then thrown away as useless. He advertiseth, that if they be coupled longer than 9. Or 10. Hours, (whichthey will be, and that sometimes for 24. Hours together, if they be letalone) either the female will receive very great hurt by it, or much seedwill remain in her belly. {91} The seed at first coming out is very white, but within a day it becomsgreenish, then red, at last by little and little gray, which colour itretains alwaies, the most coloured of an obscure gray, being the best;those grains which never quit their whiteness, having no fecundity in them. Each female emits ordinarily some 300 grains, more or less, some of themnot being able to render them all, and dying with them in their belly. Oneounce of seed will require an hundred pair of _Cases_, of as many Males asFemales. Care must be taken, that no Rats, Mice, Ants, or other Vermin, nor anyHens, or Birds, come near the Seed, they being very greedy to eat them. This is the substance of what is contained in this _French_ Author, published at _Paris_ on purpose to promote the _Making_ of _Silk_ there, aswell as it is practised already in other parts of that Kingdom; which isrepresented here, to the end, that from this occasion the design, which theEnglish Nation once did entertain of the _increasing of Mulberry trees_, and the _Breeding of Silk-worms_, for the _Making of Silk_ withinthemselves, may be renewed, and _that_ encouragement given by King _James_of Glorious memory for that purpose (witness that _Letter_ which hedirected to the Lords Lievtenants of the several shires of _England_) andseconded by his _Most Excellent Majesty_, that now is, be made use of, forthe honour of _England_ and _Virginia_, and the increase of wealth to thepeople thereof; especially since there is cause of hope, that a _doubleSilk harvest_ may be made in _one_ Summer in _Virginia_, without hindringin the least the _Tobacco_-Trade of that Countrey. * * * * * _Enquiries concerning _Agriculture_. _ Whereas the _Royal Society_, in prosecuting the _Improvements of Naturalknowledge_, have it in design, to collect _Histories of Nature and Arts_, and for that purpose have already, according to the several Inclinationsand Studies of their Members, divided themselves into divers _Commitees_, to execute the said design: Those Gentlemen, which do constitute the_Commitee_ for considering of _Agriculture_, and the _History_ and_Improvement_ thereof, have begun their work with drawing up certain {92}Heads of _Enquiries_, to be distributed to persons _Experienced inHusbandry_ all over _England_, _Scotland_, and _Ireland_, for the procuringa _faithful_ and _solid_ information of the _knowledge_ and _practice_already obtained and used in these Kingdoms; whereby, besides the aid whichby this means will be given to the general End of collecting theaforementioned _History_, every place will be advantaged by the helps, thatare found in any, and occasion ministred to consider, what improvements maybe further made in this whole matter. Now to the End, that those_Enquiries_ may be the more universally known, and those who are skilful inHusbandry, publickly invited to impart their knowledge herein, for the_common_ benefit of their Countrey, it hath been thought fit to publish the_effect_ of them in Print, and withal to desire that what such personsshall think good from their own _Knowledge_ and _Experience_ to communicatehereupon, they would be pleased to send it to the Printers of the _RoyalSociety_, to be delivered to either of the _Secretaries_ of same. TheEnquiries follow. 1. For _Arable_. 1. The several kinds of the soyls of _England_, being supposed to be, either Sandy, Gravelly, Stony, Clayie, Chalky, Light mould, Heathy, Marish, Boggy, Fenny, or Cold weeping Ground; information is desired, what kind ofsoyls your Country doth most abound with, and how each of them is prepared, when employed for _Arable_? 2. What _peculiar_ preparations are made use of to these Soyls for eachkind of Grain; with what kind of Manure they are prepared; when, how, & inwhat quantity the Manure is laid on? 3. At what seasons and how often they are ploughed; what kind of Ploughsare used for several sorts of Ground? 4. How long the several Grounds are let lie fallow? 5. How, and for what productions, _Heathy_ Grounds may be improved? And whothey are (if there be any in your Country) that have reduced _Heaths_ intoprofitable Lands? 6. What ground _Marle_ hath over head? How deep generally it lieth from thesurface? What is the depth of the _Marle_ it self? What the colour of it?Upon what grounds it is used? {93} What time of the year it is to be laidon? How many loads to an Acre? What Grains _Marled_ Land will bear, and howmany years together? How such _Marled_ Land is to be used afterwards, &c? 7. The kinds of Grain or Seed, usual in _England_, being supposed to beeither Wheat, Miscelane, Rye, Barley, Oats, Pease, Beans, Fitches, Buck-wheat, Hemp, Flax, Rape; We desire to know, what sorts of Grains aresown in your Country, and how each of these is prepared for Sowing? Whetherby _steeping_, and in what kind of Liquor? Or by mixing it, and with what? 8. There being many sorts of Wheat, as the White or Red Lammas, the beardedKentish Wheat, the gray Wheat, the red or gray Pollard, the Ducks-billWheat, the red-eared-bearded Wheat, &c. And so of Oats, as the commonBlack, Blue, Naked, Bearded in _North-wales_: and the like of Barley, Pease, Beans, &c. The Enquiry is, which of these grow in your Country, andin what Soyl; and which of them thrive best there; and whether each of themrequire a peculiar Tillage; and how they differ in goodness? 9. What are the chief particulars observable in the choice of Seed-Corn, and all kinds of Grain; and what kinds of Grain are most proper to succeedone another? 10. What Quantity of each kind is sown upon the Statute-Acre? And in whatseason of the Moon and year 'tis sowed? 11. With what instruments they do Harrow, Clod and Rowl, and at whatseasons? 12. How much an Acre of good Corn, well ordered, generally useth to yield, in very good, in less good, & in the worst years? 13. Some of the common Accidents and Diseases befalling Corn in the growthof it, being Meldew, Blasting, Smut; what are conceived to be the Causesthereof, & what the Remedies? 14. There being other Annoyances, the growing Corn is exposed to, as Weeds, Worms, Flies, Birds, Mice, Moles, &c. How they are remedied? 15. Upon what occasions they use to cut the young Corn in the Blade, or toseed it; and what are the benefits thereof? 16. What are the seasons and waies of Reaping and Ordering each sort ofGrain, before it be carried off the Ground? {94} 17. What are the several waies of preserving Grain in the Straw, within andwithout doors, from all kind of Annoyance, as Mice, Heating, Rain, &c? 18. What are the waies of separating the several sorts of Grain from theStraw, and of dressing them? 19. What are the waies of preserving any stores of separated Grain, fromthe Annoyances they are obnoxious to? 2. For _Meadows_. 1. How the above mentioned sorts of Soyl are prepared, when they are usedfor Pasture or Meadow? 2. The common Annoyances of these Pasture or Meadow Grounds being supposedto be, either Weeds, Moss, Sour-grass, Heath, Fern, Bushes, Bryars, Brambles, Broom, Rushes, Sedges, Gorse or Furzes: what are the Remediesthereof? 3. What are the best waies of Drayning Marshes, Boggs, Fenns, &c? 4. What are the several kinds of Grass, and which are counted the best? 5. What are the chief circumstances observable in the Cutting of Grass; andwhat in the making and preserving of Hay? 6. What kind of Grass is fittest to be preserved for Winter feeding? Andwhat Grass is best for Sheep, for Cows, Oxen, Horses, Goats, &c. * * * * * Advertisement. _The _Reader_ is hereby advertised, that by reason of the present Contagionin _London_, which may unhappily cause an interruption aswel of_Correspondencies_, as of _Publick Meetings_, the Printing of these_Philosophical Transactions_ may possibly for a while be intermitted;though endeavours shall be used to continue them, if it may be. _ * * * * * _LONDON, _ Printed with Licence, by _John Martyn_, and _James Allestry_, Printers tothe _Royal Society_, at the _Bell_ in St. _Pauls Church-Yard_. 1665. {95} * * * * * _Numb. _ 6. PHILOSOPHICAL_TRANSACTIONS. _ * * * * * Monday, _November_ 6. 1665. * * * * * The Contents. _An Account of a not ordinary _Burning Concave_, lately made at _Lyons_, and compared with several others made formerly. Of Monsieur _Hevelius_ his promise of communicating to the World his Invention of making _Optick Glasses_; and of the hopes, given by Monsieur _Christian Hugens_ of _Zulichem_, to perform something of the like nature; as also of the Expectations, conceived of some Persons in _England_, to improve _Telescopes_. An intimation of a way of making more lively Counterfeits of Nature in _Wax_, then are extant in _Painting_; and of a new kind of _Maps_ in a low _Relievo_, or _Sculpture_, both practised in _France_. Some _Anatomical_ Observations of Milk found in Veins instead of Blood; and of Grass found in the Wind-pipes of some Animals. Of a place in _England_, where, without Petrifying Water, Wood is turned into Stone. Of the nature of a certain Stone, found in the _Indies_ in the head of a _Serpent_. Of the way, used in the _Mogol's_ Dominions, to make _Salt-petre_. An Account of _Hevelius_ his _Prodromus Cometicus_, and of some Animadversions made upon it by a _French_ Philosopher; as also of the Jesuit _Kircher_'s _Mundus Subterraneus_. _ * * * * * _An Account of a not ordinary _Burning Concave_, lately made at _Lyons_, and compared with several others made formerly. _ An opportunity being presented to revive the publishing of these Papers, which for some Moneths hath been {96} discontinued by reason of the greatMortality in _London_, where they were begun to be Printed; it hath beenthought fit to embrace the same, and to make use thereof for the gratifyingof the Curious, that have been pleased to think well of suchCommunications: To re-enter whereupon, there offers it self, first of all aRelation of an uncommon _Burning-glass_, not long since made in _France_, in the City of _Lyons_, by one called Monsieur _de Vilette_, as it was sentto the Publisher of these Tracts, in two Letters, whereof the one was in_Latine_, the other in French, to this effect. Concerning the Efficacy of Monsieur _de Villete_ his Burning Glass, allwhat the _P. Bertet_ hath written of it, is true. We have seen the effectsof it repeated over and over again, in the Morning, at Noon, and in theAfternoon, alwaies performing very powerfully; burning or melting anyMatter, very few excepted. The _Figure_ of it is round, being thirtyInches, and somewhat better in _Diameter_. On one side it hath a Frame of aCircle of Steel, to the end that it may keep its just Measure: 'Tis easieto remove it from place to place, though it be above an hundred weight, and'tis easily put in all sorts of postures. The _burning Point_ is distantfrom the Centre of the Glass, about three Feet. The _Focus_ is about half a_Louys d'or_ large. One may pass ones hand through it, if it be donenimbly; for if it stay there the time of a second Minute, there is dangerof receiving much hurt. _Green wood_ takes fire in it, in an instant, as do also many other Bodies. A small peice of _Pot-Iron_ was melted, and _Seconds_ ready to drop down, in 40. A _Silver Peice_ of 15 _Pence_ was pierced, in 24. A _gross Nail_ (called _le Claude paisan_) was melted, in 30. The end of a _Sword-blade_ of _Olinde_, was burn'd, in 43. A _Brass Counter_ was pierced, in 06. A piece of _red Copper_ was melted ready to drop down, in 42. {97} A peice of a _Chamber Quarry-stone_ was vitrified, and put into a Glass-drop, in 45. _Steel_, whereof Watch-makers make their springs, was found melted, in 09. A _Mineral-Stone_, such as is used in Harquebusses _à rovët_, was calcin'd and vitrified, in 1. _just. _ A peice of _Morter_ was vitrified, in 52. In short, there is hardly any Body, which is not destroyed by this Fire. Ifone would melt it by it any great quantity of Mettal, that would requiremuch time, the Action of Burning not being perform'd but within the bignessof the _Focus_, so that ordinarily none but small pieces are exposed to it. One Mounsieur _de Alibert_ buys it, paying for it Fifteen hundred Livers. Since this Information, there were, upon occasion given from thence, uponthe same subject, further communicated from _Paris_ the followingParticulars. I see by two of the Letters, that you incline to believe, the Glasses of_Maginus_ and _Septalius_ do approach to that of _Lyons_: But I can assureyou, they come very far short of it. You may consult _Maginus_ his Book, where he describes his; and there are some persons here that have seen oneof his best, which had but about twenty Inches Diameter; so that this of_Lyons_ must perform at least twice as much. As to _Septalius_, we expectthe Relations of it from Intelligent and Impartial men. It cannot well becompared to that of _Lyons_: but in bigness; and in this case, if it havefive _Palms_ (as you say) that would be about 3½ feet _French_, and so itwere a Foot bigger, which would make it half as much greater in surface:But as to the Effects, seeing it burns so far off, they cannot be veryviolent. And I have heard one say, that had seen it, that it did not setWood on Fire but after the time of saying a _Miserere_. You may judge ofthe difference of the Effects, since that of _Lyons_ gathers its Beamstogether within the space of seven or eight _Lines_; {98} and that of_Septalius_ must scatter them in the compass of three Inches. Some here dointend to make of them yea and bigger ones; but we must stay till they bedone, &c. * * * * * Of _Monsieur _Hevelius_'s Promise of imparting to the World his Inventionof making _Optick Glasses_; and of the hopes given by Monsieur _Hugens_ of_Zulichem_, to perform something of the like nature; as also of theExpectations, conceived of some Ingenious Persons in _England_ to improve_Telescopes. That eminent Astronomer of _Dantzick_, Monsieur _Hevelius_, writes to hisCorrespondent in _London_, as followeth: What hath been done in the grinding of Optick-glasses in your parts, andhow those beginnings, mentioned by you formerly, do continue and succeed, Ivery much covet to hear, 'Tis now above Ten Years, since I my self inventeda peculiar way of grinding such Glasses, and reduced it also into practice;by which 'tis easie, without any considerable danger of failing, to makeand polish Optick-glasses of any _Conick_ Section, and that (which is mostnotable) in any dish of any Section of a _Sphere_: which Invention I haveas yet discovered to none, my purpose being, for the Improvement of NaturalKnowledge, to describe the whole method thereof in my _Celestial Machine_, and to propose it to the Examination and Judgment of the _Royal Society_;not doubting at all, but they will find the way true and practicable, myself having already made several Glasses by it, which many Learned Men haveseen and tryed. Monsieur _Hugens_, inquiring also in a Letter, newly written by him to aFriend of his in _England_, of the success of the attempts made by aningenious _English_ Man for perfecting such Glasses, and urging theprosecution of the same, {99} so as to shew by the effects thepracticableness of the Invention, mentions thereupon, That he intends veryshortly to try something in that kind, of the success whereof he declaresto have good hopes. Monsieur _du Son_, that excellent Mechanician, doth also at this verypresent employ himself in _London_, to bring _Telescopes_ to perfection, bygrinding Glasses of a _Parabolical_ Figure, by the means whereof he hopesto enable the Curious to discover more by a Tube of one Foot long, orthereabouts, furnished with Glasses thus figured, then can be done by anyother Tubes of very many times more that length: The success hereof will('tis thought) shortly appear. * * * * * _An Advertisement of a way of making more lively Counterfeits of Nature in_Wax_, then are extant in _Painting_: And of a new kind of _Maps_ in a low_Relievo_. Both practised in_ France. This was communicated by the Ingenious Mr. _John Evelyn_, to whom it wassent from _Paris_ is a Letter, as followeth. Here is in our Neighbourhood a _French-man_, who makes more livelyCounterfeits of Nature in _Wax_, then ever I yet saw in _Painting_, haveingan extraordinary address in modelling the Figures, and mixing the Coloursand Shadows; making the Eyes so lively, that they kill all things of thisArt I ever beheld; He pretends to make a visit into _England_ with some ofhis Peices. I have also seen a new kind of _Maps_ in low _Relievo_, or Sculpture; Forexample the Isle of _Antibe_, upon a square of about eight Foot, made ofBoards, with a Frame like a Picture: There is represented the Sea, withShips and other Vessels Artificially made, with their _Canons_ and Tackleof Wood fixed upon the surface, after a new and most admirable manner. TheRocks about the Island exactly form'd, {100} as they are upon the NaturalPlace; and the Island it self, with all its Inequalities, and Hills andDales; the Town, the Forts, the little Houses, Platform, and Canonsmounted; and even the Gardens and Platforms of Trees, with their greenleaves standing upright, at if they were growing in their Natural Colours:in _fine_, Men, Beasts, and whatever you may imagine to have anyprotuberancy above the level of the Sea. This new, delightful, and mostinstructive form of _Map_, or _Wooden Country_, you are to look upon either_Horizontally_, or _side-long_, and it affords equally a very pleasantobject. * * * * * _Some _Anatomical_ Observations of Milk found in Veins, instead of Blood;and of Grass, found in the Wind-pipes of some _Animals_. _ A curious Person wrote not long since from _Paris_, that there they had, inthe house of a Physitian, newly open'd a Mans Vein, wherein they found_Milk_, instead of _Blood_. This being imparted to Mr. _Boyle_ at _Oxford_, his Answer was, That the like Observation about _White Blood_, had beenmade by a Learned Physitian of his acquaintance, and the thing being by himlook'd upon as remarkable, he was desirous to have it very circumstantiallyfrom the said Physitian himself, before he would say more of it. The nextMoneth may bring us in this Account. The other Particular, mention'd in the Title of this Head, came in a Lettersent also by Mr. _Boyle_, in these words: I shall acquaint you, That Two very Ingenious Men, Dr. _Clark_, and Dr. _Lower_, were pleased to give me an account of a pretty odd kind ofObservation: One of them assuring me, That he had several times, in the_Lungs_ of _Sheep_, found considerable quantity of Grass in the veryBranches of the _Aspera Arteria_: And the other relating to me, That a fewWeeks since, he, and a couple of {101} Physitians, were invited to lookupon an Ox, that had for two or three daies almost continually held hisNeck streight up, and was dead of a Disease, the owner could not conjectureat; whereupon the parts belonging to the Neck and Throat, being open'd, they found, to their wounder, the _Aspera Arteria_ in its very Trunk allstuff'd with Grass as if it had been thrust there by main force: whichgives us a just cause of marvelling and inquiring, both how such a quantityof Grass should get in there; and how, being there, such an Animal couldlive with it so long. * * * * * _Of a place in _England_, where, without petrifying Water, Wood is turnedinto Stone. _ The same Searcher of Nature, that was alledged in the immediately precedentObservations, did impart also the following, in another Letter from_Oxford_, where he saith, I was a while since visited by a Gentleman, who tells me, That he met witha place in these parts of _England_, where, though there be no petrifyingSpring (for that I particularly asked) Wood is turned into Stone in the_Sandy Earth_ it self, after a better manner then by any Water I have yetseen: For I had the Curiosity to go to look upon peices of Wood, he broughtthence, and hope for the opportunity of making some tryals to examine thematter a little further, then I have yet been able to do. _Thus far thatLetter. _ Since which time, He was pleased to give this further Information of thesame matter, with a _Mantissa_ of some other Particulars, belonging to thisSubject, in these Words. I was lately making some Tryals with the Petrifyed Wood I told you off, which I find to be a very odde substance, wonderfully hard and fixed. If Ihad opportunity to Re-print the _History of Fluidity_ and _Firmness_, Icould add divers things about _Stones_, that perhaps would not be disliked;and I hope, if God vouchsafe me a little leisure, {102} to insert severalof them in fit places of that _History_, against the next Edition. Here isa certain Stone, that is thought to be Petrifyed Bone, being in shap'd likea Bone, with the Marrow taken out; but with a fit _Menstruum_, I found thatI could easily dissolve it, like other soft Stones: and possibly it mayprove as fit as _Osteocolla_, for the same Medicinal uses. * * * * * _Of the nature of a certain Stone, found in the _Indies_, in the head of a_Serpent_. _ There was, some while ago, sent by Sir _Philiberto Vernatti_, from _Javamajor_, where he resides, to Sir _Robert Moray_, for the Repository of the_Royal Society_, a certain Stone, affirmed by the presenter to be found inthe Head of a _Snake_, which laid upon any Wound, made by any venomousCreature, is said to stick to it, and to draw away all Poyson: and then, being put in Milk, to void its Poyson therein, and to make the Milk turnblew; in which manner it must be used, till the Wound be cleansed. The like Relations having been made, by several others, of such a Stone, and some also in this City affirming, to have made the Experiment withsuccess, it was thought worth while, to inquire further into the truth ofthis Matter: since which time, nothing hath been met with but anInformation, delivered by that Ingenious _Parisian_, Monsieur _Thevenot_, in his second _Tome_, of the _Relations of divers considerable Voyages_, whereof he lately presented some Exemplars to his Friends in _England_. TheBook being in French, and not common, 'tis conceived it will not be amissto insert here the said Information, which is to this effect: In the _East Indies_ and in the Kingdom of _Quamsy_ in _China_, there isfound a Stone in the Head of a certain _Serpent_ (which they call by a namesignifying _Hairy Serpents_) which heals the bitings of the same Serpent, that else would kill in 24 hours. This Stone is round, white in the middleand about the {103} edges blew or greenish. Being applyed to the Wound, itadheres to it of it self, and falls not off, but after it hath sucked thePoyson, then they wash it in Milk, wherein 'tis left awhile, till it returnto its natural condition. It is a rare Stone, for if it be put the secondtime upon the Wound, and stick to it, 'tis a sign it had not suck'd all theVenome during its first application, but if it stick not, 'tis a mark thatall the Poyson was drawn out at first. So far our _French_ Author: whereinappears no considerable difference from the written Relation beforementioned. * * * * * _Of the way, used in the _Mogol_'s Dominions, to make _Saltpetre_. _ This is delivered in the same Book of Monsieur _Thevenot_, and the mannerof it having been inquired after, by several curious Persons, to compare itwith that which is used in _Europe_, 'tis presum'd, they will not bedispleased to find it inserted here in _English_, which is as followeth: _Saltpetre_ is found in many places of the _East-Indies_, but cheifly about_Agra_, and in the Villages, that heretofore have been numerouslyinhabited, but are now deserted. They draw it out of three sorts of Earth, black, yellow, and white: the best is that which is drawn out of the black, for it is free from _common_ Salt. They work it in this manner: They maketwo Pits, flat at the bottom, like those wherein common Salt is made; oneof them having much more compass than the other, they fill _that_ withEarth, upon which they let run Water, and by the feet of People they treadit, and reduce it to the consistency of a Pap, and so they let it stand fortwo daies, that the Water may extract all the Salt that is in the Earth:Then they pass this Water into another Pit, in which it christallizes into_Saltpetre_, They let it boil once or twice in a Caldron, according as theywill have it whiter and purer. Whilest it is over the Fire, they scum itcontinually, and fill it out into great Earthen Pots, which {104} hold each25 or 30 pounds, and these they expose to clear Nights; and if there be anyimpurity remaining, it will fall to the bottom: Afterwards they break thePots, and dry the Salt in the Sun. One might make vast quantities ofSaltpetre in these parts; but the Country people feeling that _We_ buy ofit, and that the _English_ begin to do the same, they now sell us a _Maon_of 6 pounds for two _Rupias_ and a half, which we had formerly for halfthat price. * * * * * _An account of _Hevelius_ his _Prodromus Cometicus_, together with someAnimadversions made upon it by a _French_ Philosopher. _ This excellent _Dantiscan_ Astronomer, _Hevelius_, in his _Prodromus_ (byhim so call'd, because it is as a Harbinger to his _Cometography_, whichhath already so far passed the Press, that of twelve Books there are butthree remaining to be Printed) gives an account of the Observations he hathmade of the _First_ of the two late Comets; reserving those he hath made ofthe _second_, for that great Treatise, where he also intends to deliver theMatter of this _first_ more particularly, and more fully than he hath donehere. In this Account he represents the Rise, Place, Course, Swiftness, Faces andTrain of this Comet, interweaving his Conceptions both about the Region ofComets in general (whether in the _Air_, or the _Æther_?) and the Causes oftheir Generation: In the search of which latter, he intimates to havereceived much assistance from his _Telescope_. He observes this Comet not before _Decemb. _ 4/14, (though he conceives itmight have been seen since _Novemb. _ 23 _st. N. _) & he saw it no longerthen _Feb. _ 3/13: though several others have seen it both sooner, andlater: and though himself continued to look out for it till _March_ 7. _st. N. _ but fruitlesly, whereof he thinks the reason to have been its too greatdistance and tenuity. {105} He finds, its apparent Motion was not made in a _Just_ great Circle, butdeviated considerably from it; and conceives, that every Comet falls tothis deviation, when this apparent Motion grows slow, and the Star becomesStationary (which, as he saith, it doth in respect of the _Ecliptick_, notits own _Orbite_, ) Here he observes, That from _Decemb. _ 8/18, to _Decem. _30. _Jan. _ 9. Its course was almost a great Circle: but that _then_ itbegan to deflect from that Circle towards the _North_; so that afterwards, with a very notable and conspicuous Curvity, it directed its course towards_Primam Arietis_: Of which deflection, he ventures to assign the cause fromthe Cometical Matter, the various position and the distance of the Cometfrom the Earth and the Sun, the annual Motion of the Earth, and theimpressed Motion, and the inclination of the _discus_ of the CometicalBody. He is pretty positive, that without the _annual Motion_ of the _Earth_, norational Account can be given of any Comet, but that all is involved withperplexities, and deform'd by absurdities. He inquires, since all Comets have the peculiar _Ingenite_ Motion, whatkind of Line it is, they describe by that Motion of their own? whethercircular, or streight, or curve, or partly streight and partly curve? Andif curve, whether regular or irregular? if regular, whether Elliptick, orParabolar, or Hyperbolical? He answers, That this Motion is _Conical_; andjudgeth, that by the _Conick_ path all the _Phænomena_ of Comets can, without any inconveniency, be ready solved; even of that, which (byHistory) in fifty daies, passed through more then the 12 Signs in the_Zodiack_: And of that, which in two daies ran through eight Signs: and ofanother, which in 48 daies posted through all the Signs, _contra seriem_. Which how it can be explicated upon the supposition of the Earths standingstill, and upon the denying of the annual Motion thereof, he understandsnot at all. {106} He refers to his _Cometography_ these Disquisitions: whether all Comets (intheir innate Motion) move equal _spaces_ in equal _Times_? which is theswiftest, and which the slowest Motion they are capable of? what the causeof this acceleration and retardation of their true Motion? He puts it out of doubt, that they are in the _Sky_ it self, producingreasons for it that are very considerable, and alledging amongst others, That the _Parallaxes_ doe clearly evince it, which he finds far less inComets, then in the _Moon_, yea then sometimes in the _Sun_ it self. Wherehe also represents, That he hath deduced the _Horizontal Parallax_ of thisvery Comet from one onely Observation, made _Feb. _ 4. _st. N. _ by which hefound, That then it was distant from the Earth 5000 Semidiameters of thesame, or 4300000 _German_ miles. From this distance from the earth, hededuces, That on that Day when it was so remote from the Earth, its true_Diameter_ was 2560 _German_ miles, which is three times bigger then theDiameter of the Earth, and almost six times bigger then that of the Moon, whose Diameter, according to his _Theory_, is 442 _German_ miles. He finds the _Matter_ of Comets to be in the _Æther_ it self, making the_Æther_ and the _Air_ to differ only in purity, and esteeming, That the_Planets_ do emit their Exhalations, and have their _Atmospheres_ like untoour Earth. Where he affirms, That the Sun alone may cast out so much Matterat any time in one year, as that thence shall be produced not one or twoComets, equallizing the Moon in Diamiter, but very many; which if so, whatcontribution may not be expected from the other Planets? Of this Cometical Matter, he thinks, That first it is by little and littlegathered together, then coagulated and condensed, and thereby reduced to aless Diameter; but then, after a while it resolves again, and grows diluteand pale, and at last is dissipated. And accordingly he affirms, That hehath observed the Head of this Comet at first more confused, thin and pale, afterwards clearer and clearer. {107} He conceives, That all Comets do respect the _Sun_ as their _King_ and_Centre_, as _Planets_ do, making them a kind of _Spurious Planets_, thatemulate the _true_ ones in their Motion almost in all things. The _Train_, he makes nothing else but the Beams of the Sun, falling on thehead of the Comet, and passing through the same, refracted and reflected. And amongst his _Observations_ and _Schemes_ of this Comet, there occursone, wherein the Tail is _curve_, so seen by him _Decemb. _ 11/21. Heassigns the causes why the Trains do so much vary, and shews also, on whatdepends their length. Whether the _same_ Comet returns again, as the Spots in the Sun? and, whether in the time of great _Conjunctions_ they are more easily generated?and whether they can be certainly foretold? with several other Inquiries, he refers for to his _great Book_. As to _Prognostications_, he somewhat complains, That men do more inquirewhat Comets _signifie_, then what they _are_, or how they are generated andmoved; professing himself to be of the mind of those that would have Cometsrather _admired_ then _feared_; there appearing indeed no cogent reason, why the Author of Nature may not intend them rather as Monitors of his_Glory_ and _Greatness_, then of his _Anger_ or _Displeasure_; especiallyseeing that some very diligent Men (among whom is _Gemma Frisius_) takenotice of as great a number of _good_ as _bad_ Events, consequent toComets. _Seneca_ also relating, That that Comet which appeared in his time, was so happy, that it did _Cometis detrahere infamiam_, it cleared thecredit of Comets, and made People have good thoughts of them. Having given some Account of what may be look'd for in this _Prodromus_, itfollows, That some also should be rendred of the _Animadversions_ mention'dto have been made upon the same. This was done by that _Parisian_Philosopher Monsieur _Auzout_, in a Letter of his to his Country-manMonsieur _Petit_; in which he strongly conceives, That this {108}_Prodromus_ contains some mistakes, of which he chiefly singles out one, asmost considerable, in _Hevelius_'s Observation of _Feb. _ 8/18, and declaresthereupon, That he, and several very intilligent Astronomers of _France_and _Italy_ concurring with him therein, (whereas M. _Hevelius_ to himseems to stand single, as to this particular) found by their Observations, That this Comet could not, on that day of _February_, be there where M. _Hevelius_ placeth it, _viz. _ In _Prima Arietis_; unless it be said, Thatit visited that Star of _Aries_ on the 18, and returned thence the 19^{th}, into its ordinary course; in which, according to his, and his severalCorrespondents Observations the Comet on _Feb. _ 17. Was distant from that_first Star_ of _Aries_ at least 1 degree and 17 minutes; and on _February_19. (he having missed, as well as his other Friends, the Observation on_Febr. _ 18) was advanced in its way 12 or 13 minutes, but yet distant fromthe said Star _some minutes_ above a _whole degree_, and consequently farfrom having then passed it. After which time M. _Auzout_ affirms to haveseen it as well as several others, for many daies, and that until _March_7/17, observing, That about _Feb. _ 26. Or 27, when the Comet was nearest tothe often-mentioned _first_ of _Aries_, it approached not nearer thereunto, then the distance of 50. Minutes. This important Difference between two very Learned, and very deservingPersons, being come to the knowledge of some of the ablest _Philosophers_ &_Astronomers_ of _England_, hath been by them thought worthy theirExamination: and they being at this very present employed in the discussionthereof, by comparing what hath been done and published by the Dissenters, and by confronting with them their own Domestick Observations, are verylikely to discern where the mistake lies; and having discern'd it, willcertainly be found hightly impartial and ingenuous in giving their sense ofthe same. {109} * * * * * _Of the _Mundus Subterraneus_ of _Athanasius Kircher_. _ This long expected _Subterraneous World_, is now come to light, dedicated(at least the _Exemplar_, that hath been perused by the _Publisher_ ofthese _Papers_, who hears, That other _Copies_ bear Dedication to other_Great Princes_) both to the present Pope, as being esteemed by the authorto have a part of his _Apostolical Kingdom_ there; and to the _RomanEmperor_ now Regent, who indeed in his Kingdom of _Hungary_, and in severalProvinces of _Germany_, hath very many and very considerable things, worthyto be observed, under _Ground_. To give the Curious a taste of the _Contents_ of this _Volume_, and therebyto excite them to a farther search into the recesses of Nature, for thecomposure of a good _Natural History_; they may first take notice, That theAuthor, having given an account in the _Preface_, what encouragement hereceived, for writing this Book, from the opportunity of Travelling withthe _Cardinal_ of _Hassia_ into _Sicily_ (in which Voyage, he saith, He metwith, as it were, an _Epitome_ of what may be observable in theSubterraneous parts of the Earth; and in particular, with an Earth-quake of14 daies duration, very instructive to him concerning several great Secretsof Nature:) having I say, thus Prefaced, he divided his Work into 12_Books_, wherein he affirms not only to have explicated the DivineStructure of the under-ground World, and the wondrous distribution of theWork-houses of Nature, and her Majesty and Riches therein; but also to haveopened the Causes of her Effects and Productions; whence, by the Marriageof Nature and Art, a happy Issue may follow for the use and benefit ofHumane Life. In the _First_ Book, he considers the nature of the Centre of the Earth, where he delivers several _Paradoxes_ touching the same, and Discourses ofthe Motion of heavy Bodies, of Pendulems, of Projectils. {110} In the _second_ he treats of the Fabrick of the _Terrestrial Globe_, of theInfluences it receives from the Coelestial Bodies, especially the _Sun_ and_Moon_, of both which _Luminaries_ he gives a _Scheme_; of the proportionof the Earth to the Sun and Moon; of the external conformation of theEarth, its Mountains, and their concatenations, decrease and increase, together with the strange transformation thereof. Further, of the Watersencompassing the Earth, and their various Communications by hiddenPassages; as also the heighth of Mountains, and of the depth of Seas; thedimension of the _Sicilian Straights_; the Magnetical Constitution of theEarth, its Heterogeneous Nature, Interior Frame, Laboratories, Caves, Channels, &c. In the _third_: Of the Nature of the Ocean, and the diversity of itsMotions; of its general Motion from the _East_ to _West_, Currents;Reciprocations, Gulfs, Whirle-pools, Saltness, &c. In the _fourth_: Of the Nature of the Subterraneous _Fire_, its necessity, diffusiveness, food, prodigious Effects through ignivomous Mountains; asalso of the Nature of _Air_, and _Winds_, their power and variety; of thegeneral Wind, how and whence generated; of Periodical and AnniversaryWinds, and their Causes; as also of the production of Artificial Winds, forrefreshment and other advantages. To which he subjoyns a Discourse, tendingto prove, That all Meteors owe their Nativity to the Fiers of theSubterraneous World. In the _fifth_: Of the Original of Springs, Rivers, Lakes; variousdifferences and qualities of Waters, and the marks where they are to be metwith under Ground; of Waters _Medical_, hot Baths, and their Differences, Causes, Virtues; together with the Wonderful Qualities and Proprieties ofsome Springs, as to their Colour, Taste, Smell, Weight, Salubrity, Flux andreflux, Petrifying power, &c. In the _sixth_: Of the _Earth_ it self, and the great variety contained inthe Womb thereof; of the manifold Productions {111} made therein, by thevirtue of Salt and its Auxiliaries, the differences whereof are larglydiscoursed of, together with the way of extracting the same. In particularof _Saltpetre_, its Generation, Nature, Virtues; of the way of making_Gunpowder_, and the various uses thereof, as also the Nature, Qualities, Preparation, Medicinal and other uses of _Alume_ and _Vitriol_. In the _Seventh_: Of some _Fossils_, as Sand, Gravel, Earths, and theirvarious Differences, Qualities, uses Economical, Chymical, Medical:together with the strange varieties & changes happening in the Earth, andtheir causes; as also the requisits to _Agriculture_. In the _eight_: First, of _Stones_, their Origine, Concretion, differenceof Colours; and in particular, of _Gems_ and their variety, causes ofgeneration, transparency in some and colours in others; as also of theirvarious Figures and Pictures by Nature framed both in common and preciousStones, with their Causes. Secondly, of the Transformation of Juices, Salts, Plants, yea of Beasts and Men turn'd into Stone: together with thegeneration of Bony Substances under ground, by many esteemed to be theBones of _Gyants_; and of _Horny_ Substances, taken for _Unicorns_ horns:as also of _Fossile wood_ and _Coals_, Thirdly, of _Bituminous Flowers, lapis Asbestos, Amber_, and its _Electrical_ virtue; together with the wayhow Insects, little Fishes, and Plants are Intombed therein. Fourthly; ofSubterraneous _Animals_, Moles, Mice, Birds, Dragons; where is alsotreated, of those Animals that are found in the midst of Stones. In the _ninth_; First, of Poysons, their primeval Origine from Minerals, and their accidental Generation in Vegetable and Animal Bodies, togetherwith their differences; where 'tis discoursed, not only how Poysons may bebred in Men, but also, how the Poyfons of some Animals do infect and killMen; and, where the Venom of Vipers lodges, and how mad _Dogs_ and_Tarantula's_ so communicate their Poyson, as that it exserts not itsnoxiousness, till after some {112} time: Where also occasion is taken todiscourse on the Original of Diseases, and cure of Poysonous ones. Secondly, of the wonderful Nature of _Sulphur, Antimony, Quick-silver_, their origine and qualities; together with the productions of _Corals_ and_Pearls_. In the _tenth_: First of _Metallurgy_, and the way how that unctuous Body, out of which mettals are produced, is elaborated by Nature, and whattherein are _Sulphur, Salt_, and _Mercury_; besides, what it is thatrenders Mettals fluid in the Fire, but not Stones and Vegetables, &c. Secondly, of the Requisits to a perfect knowledge of the _Metallick Art_, and of the Qualities of the _Mine-master_; then of the Diseases ofMine-men, and their Cure, and the waies of purging the Mines of the Airsmalignity; as also of _Metallognomy_, or the signs of latent Mettals, andby what Art they may be discovered. Thirdly, several Accounts sent to theAuthor, upon his Inquiries by the Mine-masters themselves, or other cheifOver-seers of the Mine-works, touching the variety, nature and propertiesof Minerals, and the many Accidents happening in Mines, particularly the_Hungarian_ ones at _Schemnitz_, and those of _Tyrol_. Fourthly, of severalboth _Hydraulick_ and _Wind-Engines_, to free the Mines from Water andnoxious damps. Fiftly, Of the way of working Mettals, Gold, Silver, Copper, Iron, and particularly of the method used at _Potosi_ in _Peru_, ofextracting the Silver out of the Mineral: to which is added, a Discourse of_Salt-pits_, and the way of making Salt. In the _eleventh_, First, of _Alchimy_, its Original and Antiquity, theVessels and Instruments belonging thereunto. Secondly, of the _PhilosophersStone_, what is meant by it, and whether by means thereof true Gold can beproduced? And in general, whether there be any such thing, as a true andreal Transmutation of one Mettal into another? Where are delivered theseveral Processes of the reputed _Adepti, Raymund Lulle, Azoth, Arnold deVillanova, Paracelsus, Sendivogius, &c. _ but all exploded as fals anddeceitful. Thirdly, {113} of the decisions in Law concerning Chimical Gold, true or fals. Fourthly, what the celebrated _Philosophers Stone_ was amongthe Ancients, and what they understood by the same? In the _twelfth_: First, Of the _Seminal Principle_ of all things, itsorigine, nature and property; of the way how Nature proceeds in theGeneration of _Minerals, Vegetables, Animals_; of Spontaneous Generation;of _Zeophyts, Insects_ of all sorts, and particularly of the Worms bred inMen; together with the causes why Nature would produce such swarms ofinfinite sorts of Insects. Secondly, of the variety and differences of_Vegetables_; of the requisits to know the _virtues_ of _Plants_, and ofthe several waies of _Engrafting_. Thirdly, of the _Art of Distilling_, whereby Nature is imitated, as doing all her under-ground works, in theOpinion of this Author, by _Distillation_. Fourthly, of the _Laboratoriesof various Arts_, in which, according to Natures pattern, used in herSubterraneous Operations, strange things may be performed: where treatingof _Chymical Secrets_, the truth of the Preparation of _Aurum potabile_ isdiscussed, and the _Magisteries_ of Gold, Silver, Iron, Tin, Copper andLead, examined: to which is subjoyned an _Appendix_, furnishing such Rules, whereby Students in _Chymistry_ may be directed in their work, and trueOperations distinguished from fals ones. Fiftly, Of _Metallostaticks_, where by the mixture of Mettals and Minerals may be certainly known;together with a way of weighing the Proportions of _moist_ and _dry_, existent in every Compound, as well Vegetable and Animal, as Mineral. Sixthly, of _Glass-making_, where is treated of the Nature of _Glass_; ofthe Artificial Production of all sorts of Precious Stones, partly from theAuthors own Experiments, partly from the Communication of his Friends, andthe Collection of the best Writers upon that subject. Seventhly, of_Fire-works_, where the Invention and Preparation of Gunpowder is largelydiscoursed of, and the waies of making _Squibs, Fires burning in Water_, {114} and many others, used in Publick Festivities, are described. Eighthly, of some _Mechanical Arts_, as that of _Gold-smiths, Black smiths, Copper smiths, Wyre-drawers_, in the last whereof he resolves this_Problem_; a certain weight of Mettal, and the bigness of the hole, throughwhich the Wyre is to be drawn, being given, to find into what length somuch Mettal can be spun out. Thus you have a view of this whole _Volume_; to which it may perhaps not beamiss to adde, for a Conclusion, some of those Particulars which areesteemed by the Authour to out-shine the rest, and are here and thereinter-woven as such. For example, in the _First Part_. The use of _Pindules_, for knowing by their means the _state_ of ones_Health_, from the different beatings of the _Pulse_, p. 51. The _Chain_ of _Mountains_, so drawn over the Earth, that they make, as itwere, an _Axis_, passing from _Pole_ to _Pole_; and several transverse_ductus_, so cutting that _Axis_, as to make, in a manner, an _Equator_ and_Tropicks_ of Mountains: by which concatenation he imagines, That theseveral parts of the Earth are bound together for more firmness, p. 69. A Relation of a strange _Diver_, by his continual converse in Water, sodegenerated from himself, That he was grown more like an _Amphibium_, thana man, who, by the command of a _Sicilian_ King, went down to the bottom of_Charibdis_, and brought a remarkable account of the condition of thatplace, p. 98. A Description of the Origine of the _Nile_, as this Author found it in acertain _MS. _ of one of his own _Society_, called _Peter Pais_, whom heaffirms to have been an Eye-witness, and to have visited the Head of the_Emperor of Æthiopia_ himself _Anno_ 1618. Which _Manuscript_, he saith, was brought to _Rome_, out of _Africa_, by their _Procurator_ of _India_and _Æthiopia, p. _ 72. {115} The _Communication_ of the _Seas_ with one another by SubterraneousPassages, _viz. _ of the _Caspian_, with the _Pont Euxin_ and the _PersianGulf_; of the _Mare Mortuum_, with the _Mare Rubrum_, and of this latterwith the _Mediterranean_; as also of _Scylla_ with _Charybdis_, p. 85. 101. The Subterraneous _Store-houses_ (in all the four parts of the Earth) of_Water_, and _Fire_, and _Air_; together with their important Uses, p. 111. An account of the state of the Earth about the _Poles_, how the Waters arecontinually swallowed up by the _Northern_, and running along through theBowels of the Earth, do regurgitate at the _Southern Pole_, p. 159. A description of Mount _Vesuvius_ and _Ætna_, both visited by the Authorhimself, _Anno_ 1638. Their Dimensions, Communication, Incendiums, Paths ofFiery Torrents cast out by them, &c. As also of the _Vulcans_ in _Iceland_and _Groenland_, and their Correspondence and Effects. P. 180. An Account of that famous and strange _Whirl-pool_ upon the Coasts of_Norway_: commonly call'd _The Maelstrom_; which the Author fancies to haveCommunication, by a Subterraneous Channel, with another such _Whirl-pool_in the _Bodnick Bay_; by which commerce, according to him, the Waters, when, upon their accumulation and crowding together in one of these places, they are swallowed up by the Gulf there, carrying along with themwhatsoever is in the way and lodging it in a certain receptacle at thebottom thereof, are conveyed through the same under-ground Channel to theother Gulf; where again, upon the like flux and retumescence of Waters, they are absorbed, and through the same Channel do reciprocally run to theformer Gulf, and meeting in their impetuous Passage with the thingsformerly sunk down into the Repository, carry them aloft, with themselves;and cast them up again on the Coast of _Norway_, p. 146. A Relation of strange _Earth-quakes_, p. 220 {116} An Enumeration of all the celebrated _Medical Water, and hot Baths_, in allparts of the world, p. 236. _et seq. _ In the _Second_ Part, some of his special Observations, are, How _Stones_are _coloured_ and _figured_ under ground, p. 13. 24, 25. Natures skill in _Painting_ of _Stones_, p. 22. A whole Natural _Alphabet_ represented upon _Stones_, and all sorts of_Geometrical_ Figures, naturally Imprinted upon them, p. 23. The cause of the variety of Colours in _Prismes_, and the Authors severeJudgment concerning those, that hold them to be meerly _Phantastical_, _pag. _ 15, 16, 17. Where he also delivers an Experiment, by him countedwonderful, exhibiting all sorts of Colours by the means of _Mercury_, coagulated by the vapour of Lead, and put in a Brass spoon upon burningCoals. The cause of the curious Colours in _Birds_, p. 17. The way of Nature in the Generation of _Diamonds_, p. 21. A way of preparing such a Liquor, that shall sink into, & colour the wholeBody of Marble, so that a Picture made on the surface thereof, shall, thestone being cut through, appear also in the inmost part of the same, p. 43. A Story of a whole Village in _Africa_ turned into Stone, with all thepeople thereof, p. 50. An Experiment, representing the Generation of the _Stone_ in the _Bladder_, p. 52. An _Asbestin_ Paper, that shall last perpetually, p. 74. Several Relations of numerous Societies of People living under ground, andtheir _Oeconomy_; whereof a strange one is alledged to have been found in_England_, attested by an _English_ Author, p. 97, 98, 99. A Relation of a Man that bred a Serpent in his Stomach, which came from himof the length of one Foot and a half, affirmed by the Author to have beenseen by himself, p. 126. Of whole Forrests of Coral at the bottom of the _Red Sea_, p. 159. {117} The vanity of _Virga Divinatoria_, p. 181. A peculiar way of washing out very small _Dust-gold_, p. 198. Of some extraordinary big pieces of perfect _Natural_ Gold and Silver, p. 203. Of a very rare Mineral, sent to the Author out of the _Hungarian_ Mines, which had pure Silver branching out into Filaments, and some splendidyellow parts, which was pure Gold, and some dark parts, which was Silvermixed with Gold, 189. _Salt_ the _Basis_ of all Natural Productions, and the admirable variety ofSalts, p. 299. Strange Figures of _Plants_, p. 348. The way of producing _Plants_; p. 414. In how much time a Swallow can fly about the World, p. 411, &c. This may suffice, to give occasion to the Searchers of Nature, to examinethis Book, and the Observations and Experiments contained therein, togetherwith the Ratiocinations raised thereupon, and to make severer and moreminute Inquiries and Discussions of all. * * * * * _A farther account of an Observation above-mentioned, about _White Blood_. _ Since the Printing of the former Sheet, there is this farther account fromthe same hand. Mr. _Boyle_, I have at length, according to your desire, received from the Ingenious Dr. _Lower_, an account in writing of the Observation about _Chyle_ found inthe Blood; which though you may think strange, agrees well with someExperiments of his and mine, not now to be mentioned. The Relation, thoughshort, comprizing the main Particulats of what he had more fully told me inDiscourse, I shall give it you with little or no variation from his ownwords. {118} A Maid, after eating a good Break-fast, about seven in the Morning, was letBlood about eleven the same day in her Foot; the first Blood was receiv'din a Porringer, and within a little while it turn'd very white; the lastBlood was received in a Sawcer, which turn'd white immediately, like thewhite of a Custard. Within five or six hours after, he (the Physitian)chanced to see both, and that in the Porringer was half Blood and halfChyle, swimming upon it like a Serum as white as Milk, and that in theSawcer all Chyle without the least appearance of a drop of Blood; and whenhe heated them distinctly over a gentle fire, they both harden'd: As thewhite of an Egge when 'tis heated, or just as the _Serum_ of Blood dothwith heating, but far more white. This Maid was then in good health, andonly let Blood because she never had her Courses, yet of a very floridclear Complexion. * * * * * Note. _The _Reader_ of these Papers is desired, that in those of _Numb. 4. Pag. 60. Lin. 10_. He would be pleased to read _eight_, instead of _hundred_:this latter word having been put in by a great over-sight, and without thisCorrection, injuring that Author, whose Considerations are there related. This Advertisement should have been given in _Number 5_. But was omittedfor haste. _ * * * * * Imprimatur _Rob. Say, Vice-Cancel. _ Oxon. Oxford, Printed by _Leonard Lichfield_: for _Richard Davis_. 1665. {119} * * * * * _Num. _ 7. PHILOSOPHICAL_TRANSACTIONS. _ * * * * * Monday, _Decemb. _ 4. 1665. * * * * * The Contents. _Monsieur de _Sons_ progress in working _Parabolar_ Glasses. Some speculations of Monsieur _Auzout_ concerning the changes, likely to be discovered in the Moon. The instance of the same Person to Mr. _Hook_, for communicating his Contrivance of making with Glasses of a few feet Diameter, _Telescopes_ drawing several hundred feet; together with his Offer of recompensing that secret with another, which teaches, How to measure with a _Telescope_ the _Distances of Objects_ upon the _Earth_. The Experiment of _Kircher_, of preparing a Liquor, that shall sink into, and colour the whole Body of Marble, delivered at length. An Intimation of a Way found in _Europe_, to make good _China-Dishes_. An Account of an odd Spring in _Westphalia_, together with an Information touching _Salt-Springs_; and a way of straining _Salt-water_. Of the Rise and Attempts of a way to conveigh Liquors immediately into the Mass of Blood. _ * * * * * _Of Monsieur _de Sons_ Progress in working _Parabolar_ Glasses. _ Since what was mentioned in the immediately precedent _Tract_, touchingMonsieur _de Son's_ noble attempt of grinding Glasses of a _Parabolical_Figure, the _Publisher_ of these _Papers_ hath himself seen two_Eye-glasses_ of that shape, about one inch & a half deep, and one inch anda quarter broad, wrought by this Eminent _Artist_ with a rareSteel-instrument of his own contrivance and workmanship, and by himselfalso polished to admiration. And certainly it will be wondred at by those, {120} who shall see these Glasses, how they could be truly wrought to sucha Figure, with such a Cavity; & yet more, when they shall hear the Authorundertake to excavate other such _Eye-Glasses_ to above two inches, and_Object-glasses_ of five inches _Diameter_. He hath likewise already begunhis _Object-glasses_ for the mentioned two _Ocular_ ones, of the sameFigure of about two inches _Diameter_, which are to be left all open, yetwithout causing any colours. Of all which 'tis hoped, that shortly a fullerand more particular accompt will be given. * * * * * _Monsieur _Auzout's_ Speculations of the Changes, likely to be discoveredin the _Earth_ and _Moon_, by their respective Inhabitants. _ This Inquisitive _Philosopher_ in a letter of his, lately written to hiscorrespondent in _London_, takes occasion to discourse of hisconsiderations concerning those Changes, mentioned in the _Title_, asfollowes; I have (saith he) sometimes thought upon the _Changes_, which 'tis likely, the supposed Inhabitants of the _Moon_ might discover in our _Earth_, tosee, whither reciprocally I could observe any such in the _Moon_. Forexample, methinks, that the _Earth_ would to the people of the _Moon_appear to have a different face in the several seasons of the year; and tohave another appearance in _Winter_, when there is almost nothing green ina very great part of the _Earth_; when there are Countries all covered withsnow, others, all covered with water, others, all obscured with Clouds, andthat for many weeks together: _Another_ in _Spring_, when the Forrests andFields are green. _Another_ in _Summer_, when whole Fields are yellow &c. Me thinks, I say, that _these_ changes are considerable enough in the forceof the reflexions of Light to be observed, since we see so many differencesof Lights in the _Moon_. We have _Rivers_ considerable enough to be seen, and they enter far enough {121} into the Land, and have a bredth capable tobe observed. There are _Fluxes_ in certain places, that reach into largeCountries, enough to make there some apparent change; & in some of our Seasthere float sometimes such bulky masses of Ice, that are far greater, thanthe Objects, which we are assured, we can see in the _Moon_. Again, we cutdown whole Forrests, and drain Marishes, of an extent large enough to causea notable alteration: And men have made such works, as have producedChanges great enough to be perceived. In many places also are _Vulcans_, that seem big enough to be distinguish't, especially in the shadow: Andwhen Fire lights upon Forrests of great extent, or upon Towns, it canhardly be doubted, but these Luminous Objects would appear either in anEcclipse of the Earth, or when such parts of the Earth are not illuminatedby the Sun. But yet, I know no man, who hath observed such things in the_Moon_; and one may be rationally assured that no _Vulcans_ are there, orthat none of them burn at this time. This it is (_so he goes on_) which allCurious men, that have good _Telescopes_, ought well to attend; and I doubtnot; but, if we had a very particular _Map_ of the _Moon_, as I haddesigned to make one with a _Topography_, as it were, of all theconsiderable places therein, that We or our Posterity would find somechanges in Her. And if the _Mapps_ of the _Moon_ of _Hevelius_, _Divini_, and _Riccioli_ are exact, I can say, that I have seen there some placesconsiderable enough, where _they_ put _parts that are clear_, whereas _I_there see _dark ones_. 'Tis true that if there be _Seas_ in the _Moon_, itcan hardly fall out otherwise, than it doth upon our _Earth_, where_Alluvium's_ are made in some places, and the Sea gains upon the Land inothers. _I say_, if those Spots we see in the _Moon_, are Seas, as mostbelieve them to be; whereas I have many reasons, that make me doubt, whether they be so; of which I shall speak elsewhere. And I have sometimesthought, whether it might not be, that all the Seas of the _Moon_, if theremust be Seas, were on the side of the other _Hemisphere_, and that for thiscause it might be that the _Moon_ turns not upon its _Axis_, as our_Earth_, {122} wherein the Lands and Seas are, as it were, ballanced: Thatthence also may proceed the non-appearance of any Clouds raised there, orof any Vapors considerable enough to be seen, as there are raised upon thisEarth; and that this absence of Vapors is perhaps the cause, that no_Crepuscle_ is there, as it seems there is none, my selfe at least nothaving hitherto been able to discerne any mark thereof: For, me thinks, itis not to be doubted, but that the reputed Citizens of the _Moon_ might seeour _Crepuscle_, since we see, that the same is without comparisonstronger, than the _Light_ afforded us by the _Moon_, even when she is_full_; for, a little after Sun-set, when we receive no more than the_first_ Light of the _Sun_, the sky is far clearer, than it is in thefairest night of the _full Moon_. Mean while, since we see in _the Moon_, when she is increasing or decreasing, the Light she receives from theEarth, we cannot doubt, but that the People of the _Moon_ should likewisesee in the _Earth_ that Light, wherewith the _Moon_ illuminates it, withperhaps the difference, there is betwixt their bigness. Much rathertherefore should they see the Light of the _Crepuscle_, being, as we havesaid, incomparably greater. In the mean time we see not any faint Lightbeyond the _Section_ of the Light, which is every where almost equalystrong, and we there distinguish nothing at all, not so much that cleerestpart, which is called _Aristarchus_, or _Porphyrites_, as I have oftentryed; although one may there see the Light, which the _Earth_ sendsthither, which is sometimes so strong, that in the _Moon's_ decrease I haveoften _distinctly_ seen _all_ the parts of the _Moon_, that were _notenlightned_ by the _Sun_, together with the difference of the clear parts, and the Spots, so far as to be able to discern them all. The _Shaddows_also of all the _Cavities_ of the _Moon_ seem to be stronger, than theywould be, if there were a _Second_ Light. For, although a far off, theshaddows of our Bodies, environed with Light, seem to Us almost dark; yetthey doe not so appear so much, as the Shaddows of the _Moon_ doe; andthose that are upon the _Edge_ of the _Section_, {123} should not appear inthe like manner. But, I will determine nothing of any of these things. WhenI shall hereafter have made more frequent Observations of the Moon with my_great Telescopes_, in convenient time, I shall then perhaps learn more ofit, than I know at present, at least it will excite the _Curious_ toendeavor to make the like Observations; and it may be, others, that I havenot thought of. * * * * * _The Instance of the _same Person_ to Mr. _Hook_, for communicating hisContrivance of making, with a Glass of a Sphere of 20 or 40 foot_diameter_, a _Telescope_ drawing several hundred foot; and his offer ofrecompensing that Secret with another, teaching To measure with a_Telescope_ the _Distances of Objects_ upon the Earth. _ In _Numb. _ 4. Of these _Papers_, pag. 67. Mr. _Hook_ had intimated, that hewould shortly discover a way of his, with a _Plane-convex_ Glasse of aSphære of 20. Or 40. Feet _Diameter_, without _Veines_, and truly wroughtof that _Figure_, to make a _Telescope_, that with a single _Eye-glass_should draw 300, 400, yea 1000 feet, _without_ at all _altering theConvexity_: Monsieur _Auzout_ returns this consideration, and offer uponit, which follows: To perform (_saith he_) with a _lesser Object-glass_ the effect of a _greatTelescope_, we must find out a way to make such an _Object-glass_ toreceive as many Rayes as one will, without their being sensibly distantfrom one another; to the end, that by applying to it a _strongerEye-glass_, there may be still Beams enough to see the Object, and toobliterate the small specks and imperfections of the _Eye-glass_. And ifMr. _Hook_ hath this Invention, I esteem it one of the greatest, that canbe found in the matter of _Telescopes_. If he please to impart it to us, weshall be obliged to him; and {124} I wish, I had a secret in _Opticks_ toencourage him to that communication. If I did believe, that this would beesteemed one, To measure with a _great Telescope_ the _distance of Objects_upon the _Earth_; which I have found long since, and proposed to some byway of Paradox; _Locorum distantias ex unica statione, absque ulloInstrumento Mathematico, metiri_; I doe here promise to discover it to him, with the necessary Tables, as soon as He shall have imparted his to me;which I will use, as he shall order me. For, although the _Practise_ doenot altogether answer the _Theory_ of my Invention, because that the lengthof the _Telescopes_ admits of some Latitude; yet one comes near enough, andperhaps as Just, as by most of the wayes, ordinarily used with Instruments. That, which I am proposing, I doubt not but M. _Hook_ will soon understand, and see the determination of all Cases possible. I shall only say, that ifwe look upon the sole _Theory_, we make use of an ordinary _Telescope_, whereof the _Eye-glass_ is to be _Convexe_: for, by putting the Glasses ata little greater distance, than they are, proportionably to the distancefor which it is to serve, and by adding to it a _new Eye-glass_, the Objectwill be seen distinct, though obscure; and if the _Eye-glass_ be _Convexe_, the Object will appear erect. They may be done two manner of ways; eitherby leaving the _Telescope_ in its ordinary situation, the _Object-glass_before the _Eye-glass_; or by inverting it, and putting _this_ before_that_. But if any will make use of two _Object-glasses_, whereof the_Focus's_ are known, the distance of them will be known. If it be supposed, that the _Focus_ of the _first_ be B. And _that_ of the _second_ C, and thedistance given, B + 2D, and that D _minus_ C, be _equal_ to F; for, thisdistance will be _equal_ to B + C + F - rF² - C². And if you have the_Focus_ of the _first Object-glass_, equal to B, the distance, where youwill put the _second_ Glass equal to B + C + D, the _focus_ of the 2dGlasse will be found equal to CD/{C+D}. And if you will that the Objectshall be magnified as much with these two Glasses, as it would be with asingle one, whereof the _Focus_ {125} should be of the distance given, having the _Focus_ of the _Object-glass_ given equal to B, and the distanceto B + D; the distance between the first and the second Glass will be equalto {2B² + 2BD}/{2B + D}, whence subducting B (the _Focus_ of the_Object-glass_ given) there remains BD/{2B + D}; and if this sum besupposed equal to C, we shall easily know, by the preceding Rule, the_Focus_ of the _second_ Glass. So far M. _Auzout_, who, I trust, will receive due satisfaction to hisdesire, as soon as the happy end of the present Contagion shall give abeginning and life again to the Studies and Actions of our retired_Philosophers_. I shall onely here adde, That the Secret he mentions [_Of measuring thedistance of Places by a Telescope (fitted for that purpose) and from oneStation_] is a thing already known (if I am not mis-informed) to someMembers of our Society; who have been a good while since considering of it, and have contrived ways for the doing of it: Whether the same with those ofMr. _Auzout_, I know not. Nor have I (at the distance that I am now fromthem) opportunity of particular Information. * * * * * _An Experiment of a way of preparing a Liquor, that shall sink into, andcolour the whole Body of _Marble_, causing a _Picture_, drawn on a surface, to appear also in the _inmost_ parts of the Stone. _ This _Experiment_, having been hinted at in the next foregoing _Papers_, out of the _Mundus Subterraneus_ of _Athanasius Kircher_, and severalCurious Persons, who either have not the leisure to read VoluminousAuthors, or are not readily skilled in that Learned Tongue wherein the saidBook is written, being very desirous to have it transferred hither, it wasthought fit to comply with their desire herein. The Author therefore of the _Mundus_, &c, having seen {126} some stonesreputed to be _natural_ that had most lively Pictures, not only upon them, but passing _thorow_ their whole substance, and thereupon finding an_Artist_; skilful to perform such rare workmanship, did not only pronouncesuch stones to be _artificial_, but when that _Artist_ was unwilling tocommunicate unto him his Secret, did joyn his study and endeavors withthose of one _Albertus Gunter_ a _Saxon_, to find it out themselves:wherein having succeeded, it seems, they made the Experiments which thisIndustrious and communicative _Jesuit_ delivers in this manner: The Colours, saith he, are thus prepared; I take of _Aqua fortis_ and _AquaRegis_, two ounces _ana_; of _Sal Armoniack_ one ounce; of the best _Spiritof Wine_, two drachms; as much _Gold_ as can be had for nine _Julio_'s (a_Julio_ being about six pence English) of pure _Silver_, two drachmes. These things being provided, let the Silver, when calcined, be put into aVial; and having powred upon it the two drachmes of _Aqua fortis_, let itevaporate, and you shall have a Water yielding first a _blew_ Colour, andafterwards a _black_. Likewise put the Gold, when calcin'd, into a Vial, and having powred the _Aqua Regis_ upon it, set it by to evaporate: thenput the _Spirit of Wine_ upon the _Sal Armoniack_, leaving it also till itbe evaporated; and you will have a Golden coloured Water, which will affordyou divers Colours. And, after this manner, you may extract many_Tinctures_ of Colours out of other Mettals. This done, you may, by themeans of these two Waters, paint what Picture you please upon white Marble, of the _softer_ kind, renewing the Figure every day for several days withsome fresh superadded Liquor, and you shall find in time, that the Picturehath penetrated the _whole_ solidity of the Stone, so that cutting it intoas many parts as you will, it will always represent unto you the sameFigure on both sides. _So far he_, which how far it answers expectation, is referred to the Tryalof Ingenious Artists. In the mean time there are not wanting ExperiencedMen that scruple the Effect, but {127} yet are far from pronouncing anything positively against it, so that they doe not discourage any that haveconveniencies, from trying. But whether the way there mentioned will succeed, or not, according toexpectation: Sure it is that a Stone-cutter in _Oxford_, Mr. _Bird_, hathmany years since found out a way of doing the same thing, in effect, thatis here mentioned; and hath practised it for many years. That is, he isable so to apply a colour to the outside of polished Marble, as that itshall sink a considerable depth into the body of the stone; and thererepresent like figures or images as those are on the outside; (deeper orshallower according as he continues the application, a longer, or lesserwhile. ) Of which kind there be divers pieces to be seen in _Oxford_, _London_, and elsewhere. And some of them being shewed to his Majesty, soonafter his happy restauration, they were broken in his presence, and foundto answer expectation. And others may be dayly seen, by any who is curious, or desirous to see it. * * * * * _An Intimation of a Way, found in _Europe_ to make _China-dishes_. _ Notice was lately given by an inquisitive _Parisian_ to a friend of his in_London_, that by an Acquaintance he had been informed, that Signor_Septalio_, a Canon in _Millan_, had the Secret of making as good_Porcelane_ as is made in _China_ it self, and transparent; adding that hehad seen him make some. This as it deserves, so it will be further inquired after, if God permit. * * * * * _An Account of an odd _Spring_ in _Westphalia_, together with anInformation touching _Salt-Springs_ and the straining of salt-water. _ An observing Gentleman did lately write out of _Germany_, that in_Westphalia_ in the Diocess of _Paderborn_, is a Spring, which looses itself twice in 24 houres; coming always, after 6 houres, back again with agreat noise, and so forcibly, as {128} to drive 3 Mills not far from itssource. The Inhabitants call it the _Bolderborn_, as if you should say, the_Boysterous Spring_. _The same Person_, having mentioned the many _Salt-Springs_ in _Germany_, as those at _Lunenburg_, at _Hall_ in _Saxony_, at _Saltzwedel_ in_Brandenburger Mark_, in _Tyrol_, &c. Observes, that no Salt-water, whichcontains any Metal with it, can well be sodden to Salt in a Vessel of thesame Metal, which it self contains, except _Vitriol_ in Copper Vessels. _He adds_, that, to separate Salt from Salt-water, without Fire, if youtake a Vessel of Wax, hollow within, and every where tight; and plunge itinto the Sea, or into other Salt-water, there will be made such aseparation, that the vessel shall be full of sweet water, the Salt stayingbehind: but, though this water have no saltish taste, yet, _he saith_, there will be found a Salt in the Essay, which is the Spirit of Salt, subtile enough with the water to penetrate the Wax. * * * * * _An Account of the Rise and Attempts, of a Way to conveigh Liquorsimmediately into the Mass of Blood. _ Whereas there have lately appeared in publick some _Books_, printed beyondthe Seas, treating of the Way of _Injecting liquors into Veines_; in whichBooks the _Original_ of the _Invention_ seems to be adscribed to others, besides him, to whom it really belongs; It will surely not be thoughtamiss, if something be said, whereby the true _Inventor's_ right may beyondexception be asserted & preserved; To which end, there will need no more, than barely to represent the _Time_ when, and the _Place_ where, & amongwhom it was first started and put to tryal. To joyn all these circumstancestogether, 'Tis notorious, that at least six years since (a good whilebefore it was heard off, that any one did pretend to have so much asthought of it) the Learned and Ingenious Dr. _Christopher Wren_ did proposein the _University_ of _Oxford_ (where he now is the Worthy SavilianProfessor of _Astronomy_, and where very many Curious Persons are ready to{129} attest this relation) to that Noble Benefactor to ExperimentalPhilosophy, Mr. _Robert Boyle_, Dr. _Wilkins_, and other deserving Persons, That he thought, he could easily contrive a Way to conveigh any liquidthing immediately into the Mass of Blood; _videl_: By making Ligatures onthe Veines, and then opening them on the side of the Ligature towards theHeart, and by putting into them slender Syringes or Quills, fastened toBladders (in the manner of Clyster-pipes) containing the matter to beinjected; performing that Operation upon pretty big and lean doggs, thatthe Vessels might be large enough and easily accessible. This Proposition being made, M. _Boyle_ soon gave order for an _Apparatus_, to put it to Experiment; wherein at several times, upon several Doggs, _Opium_ & the Infusion of _Crocus Metallorum_ were injected into that partof the hind-legs of those Animals, whence the larger Vessels, that carrythe Blood, are most easy to be taken hold of: whereof the success was, thatthe _Opium_, being soon circulated into the Brain, did within a short timestupify, though not kill the Dog; but a large Dose of the _CrocusMetallorum_, made another Dog vomit up Life and all: All which is moreamply and circumstantially delivered by Mr. _Boyle_ in his Excellent Bookof the _Usefulness of Experimental Philosophy_, Part 2. Essay 2. Pag. 53. 54. 55. Where 'tis also mention'd, that the fame of this Invention and ofthe succeeding Tryals being spread, and particularly coming to theknowledge of a foreign _Ambassadour_, that was Curious, and then resided in_London_, it was by him tryed with some _Crocus Metallorum_, upon aMalefactor, that was an inferiour Servant of his; with this success, thatthe Fellow, as soon as ever the Injection began to be made, did, eitherreally or craftily, fall into a swoon; whereby, being unwilling toprosecute so hazardous an Experiment, they desisted, without seeing anyother effect of it, save that it was told the Ambassadour, that it wroughtonce downwards with him: Since which time, it hath been frequentlypractised both in _Oxford_ & _London_; as well before the _Royal Society_, as elsewhere. And particularly that Learned {130} Physitian, Dr. _TimothyClerk_, hath made it part of his business, to pursue those Experiments withmuch industry, great accurateness, and considerable observations thereon;which above two years since, were by him produced and read before the_Royal Society_, who thereupon desired him, as one of their Members, tocompleat, what he had proposed to himself upon that subject, and then topublish the same: the Effect whereof 'tis hoped, will now shortly appear, and not prove unwelcome to the Curious. Some whereof, though they may conceive, that liquors thus injected intoVeines without preparation and digestion, will make odde, commotions in theBlood, disturb Nature, and cause strange Symptoms in the Body, yet theyhave other thoughts on Liquors, that are prepared of such things, as havepassed the Digestion of the Stomach; for example, of Spirit of Urine, ofHarts-horne, of Blood &c. And they hope likewise, that besides the_Medical_ Uses, that may be made of this _Invention_, it may also serve for_Anatomical_ purposes, by filling, after this way, the vessels of an Animalas full, as they can hold, and by exceedingly distending them, discover_New_ Vessels, &c: But not now to enlarge upon the Uses, the Reader maysecurely take this Narrative, as the naked real Matter of Fact, whereby'tis as clear, as Noon day (both from the Time, and irrefragable Testimonyof very many considerable Persons in that University, who can jointlyattest it; as well as from that particular unquestionable one of Mr. _Boyle_ and his worthy Company, who were the first Eye-witnesses of theTryals made, ) that to _Oxford_, and in it, to Dr. _Christopher Wren_, thisInvention is due; and consequently, that all others, who discourse or writeof it, doe either derive it from Him, or are fallen upon the same Deviseseveral years after Him. * * * * * _Published with License. _ Oxford, Printed by _A: & L: Lichfield_, for _Ric: Davis_. 1665. {131} * * * * * _Num. _ 8. PHILOSOPHICAL_TRANSACTIONS. _ * * * * * Munday, _Januar. _ 8. 1665/6. * * * * * The Contents. _An Account of the Tryals, made in _Italy_ of _Campani's_ new Optick Glasses. A further relation of the Whale-fishing about the _Bermudas_, and upon the Coast of _New England_, and _New Netherland_. Of a remarkable Spring of _Paderborn_ in _Germany_. Of some other uncommon Springs at _Basel_ and in _Alsatia_. Of the richest Salt-springs in _Germany_. Some Observations of Strange Swarms of _Insects_, and the mischiefs done by them: as also of the Brooding of Snakes and Vipers. Observations of odd Constitutions of humane Bodies. Of a way, used in _Italy_, of preserving Ice and Snow by _Chaffe_. Directions for Sea-men bound for far Voyages, drawn up by Master _Rook_, late _Geometry_ Professour of _Gresham Colledge_. Some Observations of _Jupiter_; Eclipsed by one of his _Satellites_: and of his Conversion about his _Axis_. Of some Philosophical and Curious Books, that are shortly to come abroad. _ * * * * * _An Account of the Tryalls, made in _Italy_ of _Campani's_ new _OptickGlasses_. _ An Inquisitive _Parisian_ writes to his Correspondent in _London_, asfollows; We received lately news from _Rome_, from a very Curious Person of ouracquaintance, importing, that _Campani_ hath had the advantage of _Divini_. The Great Duke of _Toskany_, and Prince _Leopold_, his Brother, upon Tryal, made of both their Glasses, have found those of _Campani_ excel the other, and with them they have been able, easily to distinguish people {132} at 4Leagues distance: Of which I intend you more particulars hereafter. Among them are expected the _Length_ of these _Telescopes_, and theLargeness of the _Aperture_ of their _Object-glasses_. In the mean time, the _Parabolical-glasses_, formerly mentioned to be in hand here at_London_, are finishing with all possible care and industry. * * * * * _A Further Relation of the _Whale-fishing_ about the _Bermudas_, and on theCoast of _New-England_ and _New-Netherland_. _ The same Person, that communicated the particulars about the newWhale-fishing near the _Bermudas_, mentioned in the first of these_Tracts_, gives this further Information; That there have been since takenby order of the _Bermudas_ Company, sixteen of those Whales, the Oylewhereof, to the quantity of 50 or 60 Tuns arrived in _Ireland_ at_Limrick_, some few months agoe. He adds, that about two years since, there stranded upon the Coast of_New-England_ a dead Whale, of that sort, which they call _Trumpo_, havingTeeth resembling those of a Mill, and its mouth at a good distance from, and under the Nose or Trunk, and several boxes or partitions in the Nose, like those of the Tailes in Lobsters; and that that being open'd there runout of it a thin oily substance, which would candy in time; after which, the remainder, being a thick fatty substance, was taken out of the samepart, with a scoope. And this substance he affirmed to be the _SpermaCeti_; adding further, that the _Blubber_, as they call it, it self, of thesame sort of Whales, when stewed, yields on the top a creamy substance, which taken off, and thrown upon white wine, lets fall a dirtyheterogeneous sediment, but what remains aloft, affords a_Sperma-Ceti_-like matter. {133} He concluded his relation with observing, that these whales were to be metwith, between the Coast of _New-England_, and _New-Netherland_, where theymight be caught eight or nine months in the year, whereas those about the_Bermudas_ are to be found there only in the Months of _February_, _March_and _April_. Concerning the death of the Whale, which hath been related to have strandedupon _New-England_, it is not very improbable, but, (that Fish having alsomore than one Enemy, whereof a small Fish called the _Thresher_ is one, who, by Mr. _Terry's_ Relation in his _East-Indian_ Voyage, with hisnimbleness vexes him as much, as a Bee does a great Beast on the land; anda certain horny Fish another, who runs its horn into the Whal's belly) itmay have been kill'd by the latter of these two; which kind of Fish isknown, sometimes to run its horn into Ships (perhaps taking them forWhales) and there snapping it asunder; as hapned not long since to anEnglish Vessel in the _West-Indian_ Seas; the broken piece of that Hornbeing by the Master of that ship presented to the King, and now kept in HisMajesties Repository: the like whereof befel a _French_ Vessel, sailingtowards the _East-Indies_, according to the Relation, made by Monsieur_Thevenot_ in his second _Tome_ of _Curious Voyages_. * * * * * _Of a remarkable Spring, about _Paderborn_ in _Germany_. _ An inquiring Gentleman of those parts writes to his Friend in _London_, asfollows; In this Diocess of _Paderborn_, about 2 leagues from that Town, is a trebleSpring call'd _Metborn_, which has three streams, two wherof are not aboveone foot and a half distant from one another, and yet of so differingqualities, that whereas one of them is limpid, blewish, lukewarm, bubling, and holding Sal-armoniack, Ochra, Iron, Vitriol, {134} Allum, Sulphur, Niter, Orpiment, used against Epilepsie, bad Spleens, and the Wormes; theother is Ice-cold, turbid and whitish, much stronger in tast, and heavierthan the former, holding much Orpiment, Salt, Iron, Niter, and someSal-Armoniack, Allum and Vitriol; Of this all Birds, observed to drink ofit, doe dye; which I have also privately experimented by taking some of ithome, and giving it to Hens, after I had given them Oates, Barly andBread-crums; For, soon after they had drunk of it, they became giddy, reeled, and tumbled upon their backs, with convulsion-fitts, and so dyedwith a great extention of their leggs. Giving them common-salt immediatlyafter they had drunk; they dyed not so soon; giving them vineger, they dyednot at all, but seven or eight days after were troubled with the _Pipp_. Those that dyed, being open'd, their Lungs were found quite shrivelledtogether. Yet some men, that are troubled with Worms, taking a litlequantity of it, and diluting it in common water, have been observed by thismeans to kill the Worms in their bellies, so that a great number of wormscome from them; whereupon though they are sick, yet they dye not. As to thethird stream, that lyes lower than the other two, about 20 paces distantfrom them, it is of a greenish colour, very clear, and of a sowre sweettast, pleasing enough. It hath about a middle weight between the other two;whence wee guess, that it is mixed of them both, meeting there together: toconfirm which, we have mixed equal quantities, of those two, with anaddition of a litle common well-water, and have found that they, beingstirred together and permitted to setle, made just a water of the samecolour and tast of this third stream. * * * * * _Of some other not-common Springs at _Basel_ and in _Alsatia_. _ A Curious Person writes from those Places in manner following; {135} At _Basel_ the Spring, running in the _Gerbergasse_ (or _Tanners-street_)from St. _Leonard's_ Hill, is of a Blewish colour, and somewhat troubled, holding Copper, Bitumen, and Antimony, about 3 parts of the first, one ofthe second, and two of the last, as has been examined by skilful Persons. Our Tanners do water their Skins in it; and being a well-tasted andwholesome Water, it is both much drunk, and used to Bath in. It mingleswith another Spring water, call'd the _Birsick_, and with it, between the_Salt-tower_ and the _Rhine-gate_ runs into the _Rhine_. In the same Town (which abounds with Spring-waters) there are two, amongthe rest, called _Bandulph's-well_, and _Brun Zum Brunnen_, that are moreobservable then the other; the former of them having a _Camphory_ anddrying Quality, and used against Hydropical Distempers; the lattercontaining some Sulphur, Saltpeter and Gold, and being an excellent Waterto drink, much used in the principal Tavern of the City, where the chief ofthe Town do resort, and near which it runs. In _Alsatia_ in the Valley, called _Leberthal_, near _Geesbach_ (an ancientMine-work) there runs out of a _Cavern_ a foul, fattish, oily Liquor, which, though the Country-men of that place employ to the vile use ofgreasing their Wheels, instead of ordinary Wheel-grease; yet doth it affordan excellent Balsom, by taking a quantity of it, and putting it in anEarthen Pot well luted, that no steam may exhale; and then with a gentleFire at first, but a stronger afterwards, boyling it for three hourstogether; in which space it will boyl in a fourth part, and an EarthenMatter, like Pitch, will settle it self at the bottom: but on the topthereof, when cold, there will swim a fatty Substance, like Lyne-Oyl, limped and somewhat yellowish, which is to be decanted from the thickSediment, and then gently distilled in an Alembick in _Arena_, by whichmeans, there will come over two differing Liquors, one Phlegmatick, theother Oily, {136} which latter swimming on the Phlegm, is to be severedfrom it. The Phlegm is used as an excellent Resister and Curer of all thePutrefactions of the Lungs and Liver, and it heals all foul Wounds andUlcers. The Oily part, being diluted with double its quantity of distilledVineger, and brought three times over the Helm, yields a rare Balsom, against all inward and outward Corruptions, stinking Ulcers, hereditaryScurfs and Scabs: 'Tis also much used against Apoplexies, Palsies, Consumptions, Giddinesses, and Head-aches. Inwardly they take it withSuccory-water against all corruptions of the Lungs. It is a kind of_Petroleum_, and contains no other Mineral Juice, but that of _Sulphur_, which seems to be thus distilled by _Nature_ under ground; the distillationof an Oyl out of _Sulphur_ by Art, being not so easie to perform. * * * * * _Of the richest _Salt-Springs_ in _Germany_. _ An Account having been desired of those two chief _Salt-Springs_ in_Germany_, at _Hall_ and _Lunenburg_, it was lately transmitted thus: The _Salt-Springs_ at _Hall_ in _Saxony_ are four, called _Gutiaar_, the_Dutch-Spring_, the _Mettritz_, and the _Hackel-dorn_; whereof the threefirst hold near the same proportion of Salt; the last hold less, but yieldsthe purest Salt. The three first hold about seven parts of Salt, three ofMarcasit, and fourteen of water: They are, besides their Oeconomical use, employed Medicinally to Bath in, and to draw a Spirit out of it, exhibitedwith good success against Venom, and the putrefaction of the Lungs, Liver, Reins, and the Spleen. The _Salt Water_ at _Lunenburgh_, being more greenish then white, and notvery transparent, is about the same nature and hold with that of _Hall_. Ithath a mixture of Lead with it, whence also it will not be sod in LeadenPans, and if it held no Lead at all, it would not be so good, that Metalbeing judged to _purifie_ the Water: whence also the Salt of {137}_Lunenburg_ is preferred before all others, that are made of Salt Springs. * * * * * _Some Observations of swarms of strange Insects, and the Mischiefs done bythem. _ A great Observer, who hath lived long in _New England_, did upon occasion, relate to a Friend of his in _London_, where he lately was, That some fewYears since there was such a swarm of a certain sort of Insects in that_English_ Colony, that for the space of of 200 Miles they poyson'd anddestroyed all the Trees of that Country; there being found innumerablelittle holes in the ground, out of which those Insects broke forth in theform of _Maggots_, which turned into _Flyes_ that had a kind of taile orsting, which they struck into the Tree, and thereby envenomed and killedit. The like Plague is said to happen frequently in the Country of the_Cosacks_ or _Ukrani_, where in dry Summers they are infested with suchswarms of _Locusts_, driven thither by an _East_, or _South-East_ Wind, that they darken the Air in the fairest weather, and devour all the Corn ofthat Country; laying their Eggs in _Autumn_, and then dying; but the Eggs, of which every one layeth two or three hundred, hatching the next Spring, produce again such a number of Locusts, that then they do far more mischiefthan afore, unless Rains do fall, which kill both Eggs and the Insectsthemselves, or unless a strong _North_ or _North-West_ Wind arise, whichdrives them into the _Euxin_ Sea: The Hogs of that Country loving theseEggs, devour also great quantities of them, and thereby help to purge theLand of them; which is often so molested by this Vermine, that they enterinto their Houses and Beds, fall upon their Tables and into their Meat, insomuch that they can hardly eat without taking down some of them; in theNight when they repose themselves upon the ground, they cover it three, orfour Inches thick, and if a Wheel pass {138} over them, they emit a stenchhardly to be endured: All which, and much more may be fully seen in the_French_ Description of the Countries of _Poland_, made by _Monsieur deBeauplan_, and by _Monsieur Thevenot_, in his Relation of the _Cosacks_, contained in the First part of his _Curious Voyages_. * * * * * _An Observation touching the Bodies of Snakes and Vipers. _ Several have taken notice, that there is a difference between the broodingof Snakes and Vipers, those laying their Eggs in Dung-hills, by whosewarmth they are hatched; but these (Vipers) brooding their Eggs withintheir Bellies, and bringing forth live Vipers. To which may be added, Thatsome affirm to have seen Snakes lye upon their Eggs, as Hens sit upontheirs. * * * * * _Some Observations of odde Constitutions of Bodies. _ A very curious Person, studying Physick at _Leyden_, to whom had beenimparted those Relations about a Milky Substance in Veins, heretoforealledged in _Numb. _ 6. Returns, by way of gratitude, the followingObservations. There was (saith he) not many Years since, in this Country a Student, whobeing much addicted to the study of _Astronomy_, and spending very manyNights in Star-gazing, had, by the Nocturnal wet and cold temper of theAir, in such a manner obstructed the pores of his skin, that little ornothing exhaled from his Body; which appeared hence, because that theshirt, he had worn five or six weeks, was then as white as if he had wornit but one day. In the mean while he gathered a subcutaneous Water, ofwhich yet he was afterwards well cured. We have also (_saith the same_) seen here a young Maid, of about thirteenYears of age, which from the time that she was but six Years old, and beganto be about her Mother in {139} the Kitchin, would, as often as she was bidto bring her Salt, or could else come at it, fill her Pockets therewith, and eat it, as other children doe Sugar: whence she was so dried up, andgrown so stiff, that she could not stirre her limbs, and was therebystarved to death. That Learned and Observing Doctor _John Beal_, upon the perusal of theforementioned _Numb. _ 6. Was pleased to communicate this Note: To your Observation, of Milk in Veines, I can add a _Phænomenon_ of someresemblance to it, which I received above 20 years agoe from _Thomas Day_, an Apothecary in _Cambridg_; _vid. _ That himself let a man bloud in thearme, by order of Doctor _Eade_, a Physitian there. The mans bloud waswhite as Milk, as it run out of his arme, it had a little dilute redness, but immediately, as it fell into the Vessel, it was presently white; and itcontinued like drops of Milk on the pavement, where ever it fell. Theconjecture which the said Physitian had of the cause of this appearance, was, that the Patient had much fed on Fish; affirming withall, that he hadsoon been a Leper, if not prevented by Physick. * * * * * _A way of preserving Ice and Snow by Chaffe. _ The Ingenious Mr. _William Ball_ did communicate the relation hereof, as hehad received it from his Brother, now residing at _Livorne_, as follows; The Snow, or Ice-houses are here commonly built on the side of a steephill, being only a deep hole in the ground, by which meanes, they easilymake a passage out from the bottom of it, to carry away all the water, which, if it should remain stagnating therein, would melt the Ice and Snow:but they thatch it with straw, in the shape of a Saucepan-cover, that therain may not come at it. The sides (supposing it dry) they line not withany thing, as is done in St. _Jeames_'s Park, by reason of the moistness ofthe ground. This Pit they fill {140} full of Snow or Ice (taking care thatthe Ice be made of the purest water, because they put it into their wine)over-spreading first the bottom very well with _Chaffe_; by which I meannot any part of the straw, but what remains upon the winnowing of the Corn;and I think, they here use Barley-chaffe. This done, they further, as theyput in the Ice, or the Snow, (which latter they ram down, ) line it thick bythe sides with such Chaffe, and afterwards cover it well with the same; andin half a years lying so, 'tis found not to want above an eight part ofwhat it weighed, when first put in. When ever they take it out into theAire, they wrap it in this Chaffe, and it keeps to admiration. The use ofit in _England_ would not be so much for cooling of drinks, as 'tis heregenerally used; but for cooling of fruits, sweetmeats &c. _So far thisAuthor. _ The other usual way both in _Italy_ and other Countries, to conserve Snowand Ice with _Straw_ or _Reed_, is set down so punctually by Mr. _Boyle_ inhis _Experimental History of Cold_, pag. 408. 409. That nothing is to beadded. It seems _Pliny_ could not pass by these _Conservatories_, and thecooling of drinks with Ice, without passing this severe, though elegant andwitty, Animadversion upon them: _Hi Nives, illi glaciem potant, poenásquemontium in voluptatem gulæ vertunt: Servatur algor æstibus, excogitatúrqueut alienis mensibus nix algeat_, lib. 19. Cap. 4. But the _Epigrammatist_sports with it thus; _Non potare nivem, sed aquam potare rigentem_ _De nive, commenta est ingeniosa sitis. _ Martial. 14. _Ep. _ 117. * * * * * _Directions for Sea-men, bound for far Voyages. _ It being the Design of the _R. Society_, for the better attaining the Endof their Institution, to study _Nature_ rather than _Books_, and from theObservations, made of the _Phænomena_ and Effects she presents, to composesuch a {141} History of Her, as may hereafter serve to build a Solid andUseful Philosophy upon; They have from time to time given order to severalof their Members to draw up both _Inquiries_ of things Observable inforrain Countries, and _Directions_ for the Particulars, they desirechiefly to be informed about. And considering with themselves, how muchthey may increase their _Philosophical_ stock by the advantage, which_England_ injoyes of making Voyages into all parts of the World, theyformerly appointed that Eminent Mathematician and Philosopher Master_Rooke_, one of their Fellowes, and _Geometry_ Professor of _GreshamColledge_ (now deceased to the great detriment of the Common-wealth ofLearning) to think upon and set down some _Directions_ for _Sea-men_ goinginto the _East_ & _West-Indies_, the better to capacitate them for makingsuch observations abroad, as may be pertinent and suitable for theirpurpose; of which the said Sea-men should be desired to keep an exact_Diary_, delivering at their return a fair Copy thereof to the _Lord HighAdmiral_ of _England_, his Royal Highness the _Duke_ of _York_, and anotherto _Trinity-house_ to be perused by the _R. Society_. Which _Catalogue_ of_Directions_ having been drawn up accordingly by the said Mr. _Rook_, andby him presented to those, who appointed him to expedite such an one, itwas thought not to be unseasonable at this time to make it publique, themore conveniently to furnish Navigators with Copies thereof. They are such, as follow; 1. To observe the Declination of the _Compass_, or its Variation from the_Meridian_ of the place, frequently; marking withal, the _Latitude_ and_Longitude_ of the place, wherever such Observation is made, as exactly asmay be, and setting down the _Method_, by which they made them. 2. To carry _Dipping Needles_ with them, and observe the Inclination of theNeedle in like manner. 3. To remark carefully the Ebbings and Flowings of the Sea, in as manyplaces as they can, together with all the Accidents, {142} Ordinary andExtraordinary, of the Tides; as, their precise time of Ebbing and Flowingin Rivers, at _Promontories_ or _Capes_; which way their Current runs, whatPerpendicular distance there is between the highest Tide and lowest Ebb, during the Spring-Tides and Neap-Tides; what day of the _Moons_ age, and attimes of the year, the highest and lowest Tides fall out: And all otherconsiderable Accidents, they can observe in the Tides, cheifly neer Ports, and about Ilands, as in St. _Helena_'s Iland, and the three Rivers there, at the _Bermodas_ &c. 4. To make Plotts and Draughts of prospect of Coasts, Promontories, Islandsand Ports, marking the Bearings and Distances, as neer as they can. 5. To sound and marke the Depths of Coasts and Ports, and such other placesnere the shoar, as they shall think fit. 6. To take notice of the Nature of the Ground at the bottom of the Sea, inall Soundings, whether it be Clay, Sand, Rock, &c. 7. To keep a Register of all changes of Wind and Weather at all houres, bynight and by day, shewing the point the Wind blows from, whether strong orweak: The Rains, Hail, Snow and the like, the precise times of theirbeginnings and continuance, especiall _Hurricans_ and _Spouts_; but aboveall to take exact care to observe the _Trade-Winds_, about what degree of_Latitude_ and _Longitude_ they first begin, _where_ and _when_ they cease, or change, or grow stronger or weaker, and how much; as near and exact asmay be. 8. To observe and record all Extraordinary _Meteors_, Lightnings, Thunders, _Ignes fatui_, Comets, &c. Marking still the places and times of theirappearing, continuance. &c. 9. To carry with them good Scales, and Glasse-Violls of a pint or so, withvery narrow mouths, which are to be fill'd with Sea-water in differentdegrees of _Latitude_, as often as {143} they please, and the weight of theVial full of water taken exactly at every time, and recorded, markingwithall the degree of _Latitude_, and the day of the Month: And that aswell of water near the Top; as at a greater Depth. * * * * * _Some Observations concerning _Jupiter_. Of the shadow of one of his_Satellites_ seen, by a Telescope passing over the Body of _Jupiter_. _ I have received an Account from very good hands, That on the 26^{th. } of_September_ last, at half hour after seven of the Clock, was seen, both in_Holland_ and in _France_ (by curious Observers, with very good Telescopes)the shadow of one of the _Satellites_ of _Jupiter_, passing over his Body. One of those small Stars moving about his Body (which are therefore calledhis _Satellites_) coming between the Sun and it, made a small Eclipse, appearing in the Face of _Jupiter_ as a little round black Spot. TheParticulars of those Observations, when they shall come to our Hands, wemay (if need be) make them publik: Which Observations, as they are inthemselves very remarkable, and argue the Excellency of the Glasses bywhich they were discovered; So are we, in part, beholding to Monsieur_Cassini_ for them, who giving notice before hand of such Appearances to beexpected, gave occasion to those Curious Observers to look for them. * * * * * _Of a permanent Spot in _Jupiter_: by which is manifested the conversion of_Jupiter_ about his own Axis. _ Besides that Transient Shadow last mentioned, there hath been observed, byMonsieur _Cassini_, a permanent Spot in the Disque of _Jupiter_; by thehelp whereof, he hath been able to observe, not onely that _Jupiter_ turnsabout upon his own Axis, but also the Time of such conversion; which he{144} estimates to be, 9 hours and 56 minutes. For as _Kepler_ did before conjecture, from the motion of the PrimitivePlanets about the Sun as their Center, that the Sun moved about its ownAxis, but could not prove it, till by _Galileo_ and _Shiner_ the Spots inthe Sun were discovered; so it hath been thought reasonable, from theSecundary Planets moving about _Jupiter_, that _Jupiter_ is also movedabout his Axis; yet, till now, it hath not been evinced by Observation, That it doth so move; much less, in what Period of Time. And the likereason there is to judge so of _Saturn_, because of the Secundary Planetdiscovered by Monsieur _Hugens de Zulichem_ to move about it; (though suchmotion be not yet evinced from Observation:) as well as that of the_Earth_, from its Attendant the _Moon_. Whether the same may be also concluded of the other Planets, _Mars_, _Venus_, and _Mercury_, (about whom have not yet been observed anySecondary Planets to move, ) is not so evident. Yet there may be somewhat oflike probability in those. Not onely, because it is possible they may haveSecundary Planets about them, though not yet discovered; (For, we know, itwas long after those of _Jupiter_, before that about _Saturn_ wasdiscovered; and who knows, what after times may discover about the rest?)But because the Primary Planets being all in like manner inlightned by theSun, and (in all likely hood) moved by it; it is likely that they be movedby the same Laws and Methods; and therefore, turn'd about their own Axis, as it is manifest that some of them are. But, as for the Secundary Planets, as well those about _Jupiter_, as thatabout _Saturn_; it is most likely that they have no such Rotation upontheir Axis. Not so much because, by reason of their smalness, no such thinghath been yet observed, (or, indeed, could be, though it were true;) Butbecause they being Analogical to our _Moon_, it is most likely that theyare moved in like manner. Now, though it be {145} true, that there is somekind of _Libration_ of the Moon's body, so that we have not precisely justthe same part of it looking towards us; (as is evident by _Hevelius_observations, and others;) yet is there no Revolution upon its Axis; thesame part of it, with very little alteration, always respecting us, as isto be seen in _Hevelius_ his Tratise _de Motu Lunæ Libratorio_, and indeed, by all those who have written particularly of the spots on the Moon; and isuniversally known to all that have with any curiosity viewed it withTelescopes. * * * * * _Of some Philosophical and curious Books, that are shortly to come abroad. _ 1. Of the _Origine_ of _Forms_ and _Qualities_, deduced from _Mechanical_Principles; by the Honorable _Robert Boyle_ Esq. 2. _Hydrostatical Paradoxes_, by the same. Both in _English_. 3. A Tract of the _Origine_ of the _Nile_, by Monsieur _Isaac Vossius_, opposed to that of Monsieur _de la Chambre_, who is maintaining, That_Niter_ is the principal cause of the Inundation of that River. 4. A Dissertation of _Vipers_, by _Signor Redi_, an _Italian_. 5. A Discourse of the _Anatomy_ of _a Lyon_, by the same. 6. Another, _De Figuris Salium_, by the same. 7. A Narration of the Establishment of the _Lyncei_, an _Italian_ Academy, and of their Design and Statutes: the Prince _Cesi_ being the Head of them, who did also intend to establish such Philosophical Societies in all partsof the World, and particularly in _Africa_ and _America_, to be by thatmeans well informed of what considerable productions of Nature were to befound in those parts. The Author yet _Anonymus_. 8. To these I shall add, a Book newly Printed in _Oxford_ (and not yetdispersed) being, _A Catalogue of Fixed Stars_ with their _Longitudes, Latitudes, and Magnitudes_, according to the _Observations_ of _Uleg-Beig_(a King, and famous Astronomer, who was _Great-Grand-childe_ to the famous{146} _Tamerlane_, and one of his Successors in some of his Kingdoms) madeat _Samarcand_, his cheief seat, (for the year of the Hegira 841, for theyear of Christ 1427), who not finding the _Tables_ of _Ptolemy_ to agreesufficiently with the Heavens, did with great diligence, and expense, makeobservations anew; as _Tycho Brahe_ hath since done. It is a small part ofa larger _Astronomical Treatise_ of his, whereof there be divers _Persian_Manuscript Copies in _Oxford_. Out of which this is Translated andPublished, both in _Persian_ and _Latine_, by Mr. _Thomas Hyde_, nowLibrary Keeper to the _Bodleyan_ Library in _Oxford_: (with Commentaries ofhis annexed:) Like as another part of it hath formerly been by Mr. _JohnGraves_. And it were a desirable work that the whole were Translated, thatwe might be the better acquainted with what was the Eastern Astronomy atthat time. * * * * * _Published with License. _ Oxford, Printed by _A: & L: Lichfield_, for _Ric: Davis_. 1666. {147} * * * * * _Num. _ 9. PHILOSOPHICAL_TRANSACTIONS. _ * * * * * _Munday_, _Feb. _ 12. 1665/6. * * * * * The Contents. _An _Apendix_ to the _Directions_ for Seamen, bound for far voyages. Of the judgment of some of the _English_ Astronomers, touching the difference between two learned men, about an Observation made of the first of the two late _Comets_. Of a _Correspondency_, to be procured, for the finding out of the _True_ distance of the _Sun_ and _Moon_ from the Earth. Of an Observation not long since made in _England_ of _Saturn_. An Account of some _Mercurial_ Observations, made with a _Barometer_, and their Results. Some Observations of _Vipers_, made by an _Italian_ Philosopher. _ * * * * * _An _Appendix_ to the _Directions_ for Seamen, bound for far Voyages. _ Whereas it may be of good use, both _Naval_ and _Philosophical_, to know, both how to sound depths of the sea _without a Line_, and to fetch up waterfrom any depth of the same; the following waies have been contrived by Mr. _Hook_ to perform both; (which should have been added to the lately printed_Directions for Seamen_, if then it could have been conveniently done. ){148} [Illustration] _First_, for the sounding of depths without a Cord, consider _Figure_ 1, and accordingly take a Globe of _Firr_, or _Maple_, or other light Wood, asA: let it be well secured by Vernish, Pitch, or otherwise, from imbibingwater; then take a piece of Lead or Stone, D, considerably heavier thenwill sink the Globe: let there be a long Wire-staple B, in the Ball A, anda springing Wire C, with a bended end F, and into the said staple, press inwith your fingers the springing Wire on the bended end: and on it hang theweight D, by its ring E, and so let Globe and all sink gently into thewater, in the posture represented in the first _Figure_, to the bottom, where the weight D touching first, is thereby stopt; but the Ball, being bythe _Impetus_, it acquired in descending, carried downwards a little afterthe weight is stopt, suffers the springing wire to fly back, and therebysets it self at liberty to reascend. And, by observing the time of theBall's stay under water (which may be done by a Watch, having minuts andseconds, or by a good Minut-glass, or best of all, by a Pendulum vibratingseconds) you will by this way, with the help of some _Tables_, come to knowany depth of the sea. Note, that care must be had of proportioning the weight and shape of theLead, to the bulk, weight, and figure of the Globe, after such a manner, asupon experience shall be found most convenient. In some of the Tryals already made with this Instrument, the Globe being ofMaple-wood, well covered with Pitch to hinder soaking in, was 5-13/16inches in diameter, and weighed 2½ pounds: the Lead of 4½ pounds weight, was of a _Conical_ figure, 11. Inches long, with the sharper end downwards, 1-9/16 inches at the top, and 1/16 at the bottom in diameter. And in thoseExperiments, made in the _Thames_, in the depth of 19. Foot water, therepassed between the Immersion and Emersion of the Globe, 6. Seconds of anhour; and in the depth of 10. Foot water, there passed 3½ seconds orthereabout: From many of which kind of Experiments it will likely not behard to finde {149} out a method to calculate, what depth is to beconcluded from any other time of the like Globes stay under water. [Illustration] In the same Tryals, made with this Instrument in the said River of_Thames_, it has been found, that there is no difference in time, betweenthe submersions of the Ball at the greatest depth, when it rose twoWherries length from the place where it was let fall (being carried by theCurrent of the _Tide_) and when it rose within a yard or so of the sameplace where it was let down. The _other_ Instrument, for Fetching up water from the depth of the sea, is(as appears by _Figure_ 2. ) a square woodden _Bucket_ C, whose bottoms_EE_, are so contrived, that as the weight A, sinks the Iron B, (to whichthe Bucket C, is fastned by two handles DD, on the ends of which are themoveable bottoms or Valves EE, ) and thereby draws down the Bucket, theresistance of the water keeps up the Bucket in the posture C; whereby thewater hath, all the while it is descending, a clear passage through;whereas, as soon as the Bucket is pulled upwards by the Line F, theresistance of the water to that motion beats the Bucket downward, and keepsit in the posture G, whereby the Included water is preserved from gettingout, and the Ambient water kept from getting in. By the advantage of which Vessel, it may be known, whether sea water beSalter at and towards the bottom, then at or near the top: Likewise, whether in some places of the sea, any sweet water is to be found at thebottom; the _Affirmative_ whereof is to be met with in the _East Indian_Voyages of the industrious _John Hugh Van Linsckoten_, who page 16 of thatBook, as 'tis _Englished_, records, that in the _Persian Gulph_, about theIsland _Barem_, or _Baharem_, they fetch up with certain Vessels (which hedescribes not) water out of the sea, from under the salt-water, four orfive fathom deep, as sweet, as any Fountain water. {150} * * * * * _Of the Judgement of some of the _English_ Astronomers, touching thedifference between two learned men, about an Observation made of the Firstof the two late _Comets_. _ [Sidenote: _By _Telescopical_ Stars are understood such, as are not seen, but by the help of a Telescope. _] Whereas notice has been taken in _Num. _ 6. Of these _Transactions_, thatthere was some difference between those two deservedly celebratedPhilosophers, _Monsieur Hevelius_ and _Monsieur Auzout_, concerning anObservation, made by the former of them, on the 8/18 of _February_ 1665. &that thereupon some Eminent _English_ Astronomers, considering theimportance of the dispute, had undertaken the examination thereof; it will, 'tis conceived, not be unacceptable to such, as saw those Papers, to beinformed, what has been done and discerned by them in that matter. Theyhaving therefore compared the Printed Writings of the two Dissenters, andwithall consulted the observations made with _Telescopes_ at home, by someof the most intelligent Astronomers amongst them, who have attentivelyobserved the Position of that _Comet_ to the _Telescopical_ stars, that layin its way; Do thereupon Joyntly conclude, that, whatever that Appearancewas, which was seen near the _First Star_ of _Aries_, by _MonsieurHevelius_ (the truth of whose relation concerning the same, they do in nowise question) the said _Comet_ did not come neer that _Star_ in the left_Ear_ of _Aries_, where the said M. _Hevelius_ supposes it to have passed, but took its course neer the _Bright Star_ in its _Left Horn_, according to_Bayers_ Tables. And since that the Observations of judicious both _French, Italian, & Dutch_ Astronomers (as many of them, as are come to theknowledge of the _English_) do in the main fully agree with theirs, they donot at all doubt, but that, there being such an unanimous {151} consent inwhat has been just now declared, & the Controversie being about _Matter offact_, wherein Authority, Number, and Reputation must cast the Ballance, Mons. _Hevelius_, who is as well known for his Ingenuity, as Learning, willjoyn and acquiesce in that sentiment. * * * * * _Of a correspondency, to be procured, for the Finding out the _True_distance of the _Sun_ and _Moon_ from the Earth, by the _Paralax_, observedunder (or neer) the same _Meridian_. _ Seeing that the knowledge of this distance may prove of important Use, forthe Perfecting of Astronomy, and for the better establishing the doctrineof _Refractions_, it is in the thoughts of some very curious Persons in_England_, for the finding out the same, to settle a Correspondency withsome others abroad, that are understanding in Astronomical matters, andlive in places farr distant in _Latitude_, and under (or near) the same_Meridian_. To perform which, the following Method is proposed to be observed; _viz. _That at certain times agreed on by two Observatours, making use of_Telescopes_, large, good and well fitted for this purpose, by a measuringrod, placed within the Eye glass at a convenient distance, that it may bedistinctly seen, and serve for measuring small distances by minuts andseconds (which is easie enough in large _Telescopes_) that, I say, each ofsuch observers, thus furnish't shall observe the visible way of the _Moon_among the _Fixt Stars_, (by taking her exact distance from any _FixtStarr_, that lyes in or very near her way, together with the exact time ofher so appearing) and the then apparent Diameter of her Disk; continuingthese Observations every time for two or three hours; that so, {152} ifpossible, two exact observations of her _Apparent_ place among the _FixtStars_ being made, at two places thus distant in _Latitude_, and as near asmay be under the same _Meridian_, by these Observators concurring at thesame time, her true and exact distance may be hence collected, not onelyfor that time, but at all other times, by any single Observator's viewingher with a _Telescope_, and measuring exactly her _Apparent_ Diameter. Itwere likewise desirable, that as often as there happens any considerable_Eclipse_ of the _Sun_, that this also might be observed by them, notingtherein the exact measure of the greatest Obscuration compared with thethen _Apparent_ Diameter of his Disk. For by this means, after the distanceof the _Moon_ hath been exactly found, the distance of the _Sun_ willeasily be deduced. As for the time, fittest for making Observations of the _Moon_, that willbe, when she is about a Quarter or somewhat less illuminated, because thenher light is not so bright, but that with a good _Telescope_ she may beobserv'd to pass close by, and sometimes over several _Fixt Stars_; whichis about four or five days before or after her Change: Or else at any othertime, when the _Moon_ passes near or over some of the bigger sort of _FixtStars_, such as of the first or second _Magnitude_; which may be easilycalculated and foreseen: Or best of all, when there is any _Totall Eclipse_of the _Moon_; for then the smallest _Telescopical Stars_ may be seen closeadjoyning to the very body of the _Moon_. Of all which particulars the twoCorrespondents are to agree, as soon as he, that is to joyn abroad, shallbe found out; whereupon they are mutually to communicate to each other, what they shall have thus observed in each place. * * * * * _Of an Observation, not long since made in _England_, of _Saturn_. _ [Illustration] This Observation was made by Mr. _William Ball_, {153} accompanied by hisbrother, Dr. _Ball_, _October_ 13. 1665. At six of the Clock, at _Mainhead_near _Exeter_ in _Devonshire_, with a very good _Telescope_ near 38 footlong, and a double Eye-glass, as the observer himself takes notice, adding, that he never saw that _Planet_ more distinct. The observation isrepresented by _Figure_ 3. Concerning which, the Author saith in his letterto a friend, as follows; This appear'd to me the present figure of_Saturn_, somewhat otherwise, than I expected, thinking it would have beendecreasing, but I found it full as ever, and a little hollow above andbelow. Whereupon the Person, to whom notice was sent hereof, examining thisshape, hath by Letters desired the worthy Author of the _Systeme of thisPlanet_, that he would now attentively consider the present _Figure_ of his_Anses_ or _Ring_, to see whether the appearance be to him, as in this_Figure_, and consequently whether he there meets with nothing, that maymake him think, that it is not _one_ body of a Circular Figure, thatembraces his _Diske_, but _two_. And to the end that other Curious men, in other places might be engaged, tojoyn their Observations with him, to see, whether they can find the likeappearance to that, represented here, especially such Notches orHollownesses, as at A and B, it was thought fit to insert here the newlyrelated Account. * * * * * _A Relation of some _Mercurial_ Observations, and their Results. _ Modern _Philosophers_, to avoyd Circumlocutions, call that Instrument, wherein a Cylinder of Quicksilver, of between 28. And 31. Inches inAltitude, is kept suspended after the manner of the _Torricellian_Experiment, a _Barometer_ or _Baroscope_, first made publick by that NobleSearcher of Nature, Mr. _Boyle_, and imployed by Him and others, to detectall the minut variations in the Pressure and weight of the Air. For themore {154} curious and nice distinguishing of which small changes, Mr. _Hook_ in the _Preface_ to his _Micrography_, has described such anInstrument with a _Wheel_, contrived by himself, and, by these two lastyears trials of it, constantly found most exact for that purpose: whichbeing so accurate, and not difficult to be made, it were desirable, thatthose who have a Genius and opportunities of making Observations of thiskind, would furnish themselves with such of these Instruments, as wereexactly made and adjusted according to the Method, delivered in the newlymentioned place. To say something of the Observations, made by this Instrument, and withalto excite studious _Naturalists_ to a sedulous prosecution of the same, the_Reader_ may _first_ take notice, that the lately named Mr. _Boyle_ hath(as himself not long since did intimate to the Author of these _Tracts_)already made divers Observations of this kind in the year 1659. And 1660. Before any others were publick, or by him so much as heard of; though hehas hitherto forborn to divulge them, because of some other Papers (inwhose Company they were to appear) which being hindred by other studies andemployments, he hath not as yet finished. _Next_, that, besides several others, who, since have had the curiosity ofmaking such observations, the Worthy and Inquisitive Dr. _John Beal_, isdoing his part with much assiduity (of which he hath by several Lettersacquainted his Friends in _London_) both by observing himself, and byprocuring many Correspondents in several places in _England_ for the samepurpose; judging it of great importance, that Observations of this kind bemade in parts somewhat distant from one another, that so from many ofthose, accurately made and then compared, it may be discovered, whether theAire gravitates more in the parts of the Earth lying more _East_ or _West_, _North_ or _South_? whether on such as lie neerer to the _Sea_, or furtherup into the _Mainland_? in hotter or colder weather? whether in {155} highWinds or Calms? whether in wet weather or dry? whether most when a North, or when a South, when an East or a West wind blows? and whether it keepsthe same seasons of Changes? and whether the seasons and changes of the Airand Weather can be thereby discover'd, and the now hidden causes of manyother _Phænomena_ detected? The said _Doctor_ is so much pleased with the discovery already made by thehelp of this Instrument, that he thinks it to be one of the most wonderfulthat ever was in the World, if we speak of strangeness, and just wonder, and of Philosophical importance, separate from the interest of lucre. For(_saith he in one of his Letters_) who could ever expect, that we menshould find an Art, to weigh all the Air that hangs over our heads, in allthe changes of it, and, as it were, to weigh, and to distinguish by weight, the Winds and the Clouds? Or, who did believe, that by palpable evidence weshould be able to prove, the _serenest_ Air to be most heavy, and the_thickest_ Air, and when darkest Clouds hang neerest to us, ready todissolve, or dropping, _then_ to be lightest. And though (_so he goes on_)we cannot yet reach to all the Uses and Applications of it, yet we shouldbe entertain'd for a while, by the truly Honourable Mr. _Boyle_, as theleading person herein, upon the delight and wonder. The _Magnet_ was knownmany hundreds of years before it was applied to find out _New Worlds_. Tome (_saith he_) tis a wonderful delight, that I have alwaies in my Studybefore my eye such a _Curious Ballance_. Having thus in _General_ expressed his thoughts about this Invention, andthe singular pleasure, he takes in the Observations made therewith, hedescends to particulars, and in several Letters communicates them to hisCorrespondent, as follows: [Sidenote: _The Exclusion of _all_ Air is here necessary, because Air beingsubject to the operation of Heat and Cold, if any of it remain in the_Barometer_, it will cause it to vary from shewing the true Pressure of theAir. _] 1. My _Wheel-barometer_ I could never fill so exactly with _Mercury_ as toexclude _all_ Air; and therefore I trust more {156} to a _Mercurial_ Cane, and take all my Notes from it. This Cane is but 35. Inches long, of a veryslender Cavity, and thick Glass. This may easily be conveyed to any place, for Trials. The Vessel for the stagnating _Mercury_, into which the saidCane is immersed, is about two _Inches_ wide. The _Mercury_ so well fill'd, that for some daies it would not subside, but hung to the top of theGlass-cane. I keep it in a Closet pretty close, 9. Foot high, 8. Footbroad, 15. Foot long; neer a Window. This I note, because possibly thecloseness of the room may hinder, that it gives not the full of allChanges, as it might in a more passable Air. 2. In all my Observations from _May_ 28. 1664 to this present (_December_9. 1665. ) the Quicksilver never ascended but very little above 30¼ Inches. 3. It ascended very seldom so high (_videl. _ to 30¼ Inches) chiefly_Decemb. _ 13. 1664. The weather being fickle-fair, Evening. 4. I find by my _Calender_ of _June_ 22. 1664. At 5. In the Morning, in atime of long setled fair weather, that the _Mercury_ had ascended abouthalf an Inch higher then 30: but I fear some mistake, because I then tookno impression of _wonder_ at it; yet for 3. Or 4. Daies, at that time itcontinued high, in well-setled, fair and warm weather; most part above 30. Inches. So that I may note, the _Mercury_ to rise as high in the hottest_Summer_, as in the coldest _Winter-weather_. [Sidenote: _Perhaps this is from some included Air. _] 5. Yet surely I have noted it ascend a little higher for the Coldness ofthe Weather; and very frequently, both in {157} Winter and Summer to behigher in the cold Mornings and Evenings, then in the warmer Mid-day. 6. Generally in setled and fair weather both of Winter and Summer, the_Mercury_ is higher, than a little _before_ or _after_, or _in_ Rainyweather. 7. Again, generally it descended lower after Rain, than it was before Rain. [Sidenote: _It seems these were _Easterly_ winds. _] 8. Generally also it falls in great winds; and somewhat it seem'd to sink, when I open'd a wide door to it, to let in stormy winds; yet I have foundit to continue very high, in a long stormy wind of 3. Or 4. Daies. 9. Again, generally it is higher in an _East_ and _North_-wind. (_Cæterisparibus_) than in a _South_ and _West_-wind. 10. I tryed several times, by strong fumes and thick smoaks to alter theAir in my Closet; but I cannot affirm, that the _Mercury_ yielded any more, then might be expected from some increase of heat. Such as have exact_Wheel-Barometers_, may try whether Odors or Fumes do alleviate the Air. 11. In this Closet I have not in all this time found the extreamest changesof the Quicksilver to amount to more, than to 2¾, or to 2-7/8. Inches, atmost. 12. Very often I have found great changes in the Air, without anyperceptible change in the _Barometer_; as in the dewy nights, when themoisture descends in a great quantity, and the thickness sometimes seems tohide the Stars from us: In the days foregoing, and following, the Vaporshave been {158} drawn up so _Invisibly_, that the Air and Sky seem'd veryclear all day long. This I account a great change between ascending anddescending Dews and Vapors (which import Levity and Weight, ) and betweenthick Air and clear Air: which changes do sometimes continue in theAlternative course of day and night, for a week or fortnight together; andyet the _Baroscope_ holding the same. 13. Sometimes (I say not often) the _Baroscope_ yields not to other verygreat changes of the Air. As lately (_December_ 18. ) an extraordinarybright and clear day; and the next following quite darkened, some Rain andSnow falling; but the _Mercury_ the same: so in high winds and calms thesame. 14. I do conceive, that such as converse much _Sub dio_, and walk muchabroad, may find many particulars much more exactly, then I, who have noleisure for it, can undertake. To instance in one of many, _December_ 16. Last, was a clear cold day, very sharp and strong _East_ wind, the_Mercury_ very near 30. Inches high, about three in the afternoon, I saw alarge black cloud, drawing near us from the _East_ and _South-East_, withthe _East-wind_. The _Mercury_ changed not that day nor the day following;the Stars and most of the sky were very bright and clear till Nine of theClock; and then suddenly all the sky was darkned, yet no change of weatherhappened; _December_ 17. The frost held, and 'twas a clear day, till abouttwo of the clock in the afternoon; and then many thick clouds appear'd lowin the _West_; yet no change of the weather here; the Wind, Frost, andQuick-silver, the same, _December_ 18. The _Mercury_ fell almost ¼ of aninch, and the sky and Air so clear and bright and cold with an _East-wind_, that I wondred what could cause the _Mercury_ to descend. I Expected, itshould have ascended, as usually it does in such clear skys. Casually Isent my servant abroad, and he discovered the remote Hills, about 20. Milesoff, cover'd with {159} snow, This seem'd to manifest, that the Air, beingdischarged of the clouds by snow, became lighter. 15. I have seldom seen the change to be very great, at any one time. For, though I do not now take a deliberate view of my Notes, yet I wonder'd onceto see, that in one day it subsided about ¾ of an inch. 16. Of late I have altered my Method upon the _Barometer_, observing it, asit is before my Eyes, all day long, and much of the night, being watchfulfor the moments of every particular change, to examine, what cause in theAir and Heavens may appear for such changes. And now my wonder is, to see, how slow it is, it holding most between the nine and twentieth andthirtieth inch of late. 17. I must now (_January_ 13. 1665/6) tell you, that the _Mercury_ standsat this time (as it did also yesterday) a quarter above 30. Inches; yetboth days very dark and cloudy, sometimes very thick and misty Air; whichseldom falls out. For, for the most part, I see it higher in clearestsetled weather, than in such cloudy and misty Foggs. This thick Air anddarkness hath lasted above a week; lately more Cold, and _East_ and_North-East_ wind. [Sidenote: _This seems to be wished, because the motion of the _Mercury_may be more free in a wider Cane. _] _Thus far_ the Notes of this Observing _Divine_; of which Mr. _Boyle_, towhom they were also communicated, entertains these thoughts, that they seemto him very faithfully made, and do for the main, agree well enough withhis observations, as far as he remembers, not having them, it seems, atthat time, when he wrote this, at hand; and though it be wished by him, that the Observer's Glass-Cane had been somewhat bigger; yet his diligencein fitting it so carefully, or rather so skilfully, as is above-mentioned, is much by him commended. {160} * * * * * _Some Observations of _Vipers_. _ A curious _Italian_, called _Francesco Redi_, having lately had anopportunity, by the great number of Vipers, brought to the _Grand Duke_ of_Toscany_ for the composing of _Theriac_ or _Treacle_, to examine what isvulgarly delivered and believed concerning the Poyson of those Creatures, hath, (according to the account, given of it in the French _Journal desScavans_, printed _January_ 4. 1665/6) performed his undertaking with muchexactness, and published in an Italian tract, not yet come into _England_, these Observations. 1. He hath observed, that the poyson of Vipers is neither in their _Teeth_, nor in their _Tayle_, nor in their _Gall_: but in the two _Vesicles_ or_Bladders_, which cover their teeth, and which coming to be compressed, when the Vipers bite, do emit a certain yellowish Liquor, that runs alongthe teeth and poysons the wound. Whereof he gives this proof, that he hathrub'd the wounds of many Animals with the _Gall_ of Vipers, and prickedthem with their _Teeth_, and yet no considerable ill accident follow'd uponit, but that as often as he rubbed the wounds with the said yellow Liquor, not one of them escaped. 2. Whereas commonly it hath hitherto been believed, that the poyson ofVipers being swallowed, was present death; this _Author_, after manyreiterated Experiments, is said to have observed, that in Vipers there isneither Humour, nor Excrement, nor any part, not the _Gall_ it self, that, being taken into the Body, kills. And he assures, that he hath seen meneat, and hath often made Bruit Animals swallow all that is esteem'd mostpoysonous in a Viper, yet without the least mischief to them. Whence heshews, that it needs not so much to be wondred at, that certain _Empiricks_swallow the juyce of the {161} most venomous Animals without receiving anyharm thereby; adding, that, which is ascribed to the vertue of their_Antidote_, ought to be attributed to the nature of those kinds of Poysons, which are no poysons, when they are swallow'd, (for which Doctrine he alsoalledges _Celsus_) but onely when they are put into wounds. Which also hasbeen noted by _Lucan_, who introduces _Cato_ thus speaking; _Noxia serpentum est admisto sanguine pestis, _ __Morsu_ virus habent, & fatum _dente_ minantur;_ __Pocula_ morte carent. _ And what also some Authors have affirm'd, _videl. _ That it is mortal, toeat of the Flesh of creatures killed by Vipers; or to drink of the Winewherein Vipers have been drowned; or to suck the wounds that have been madeby them, is by this Authour observed to be wide of truth. For he assures, that many persons have eaten Pullets and Pigeons, bitten by Vipers, withoutfinding any alteration from it in their health. On the contrary, hedeclares, That it is a soveraign Remedy against the biting of Vipers, tosuck the wound; alledging an Experiment, made upon a Dog, which he causedto be bitten by a Viper at the nose, who by licking his own wound saved hislife. Which he confirms by the example of those people, celebrated in_History_ by the name of _Marsi_ and _Psilli_, whose Employment it was, toheal those, that had been bitten by Serpents, by sucking their wounds. 3. He adds, that although _Galen_ and many modern _Physitians_ do affirm, that there is nothing, which causeth so much thirst, as Vipers-flesh, yethe hath experimented the contrary and knows divers persons, who did eat theflesh of Vipers at all their meals, and yet did assure him, they never wereless dry, then when they observed that kind of Diet. 4. As for the Salt of Vipers, whereof some _Chymists_ have {162} so greatesteem, he saith, that it hath no _Purging_ vertue at all in it; addingthat even of _All Salts_, none hath more vertue than another, as hepretends to have shew'd in an other _Book_ of his, _De natura salium_;which also hath not been yet transmitted into these parts. 5. He denies, what _Aristotle_ assures, and what _Galen_ saith to haveoften tryed, that the _Spittle_ of a _Fasting_ person kills Vipers; and helaughs at many other particulars, that have been delivered concerning the_Antipathy_ of Vipers unto certain things; and their manner of Conceptionand Generation, and several other properties, commonly ascribed to them;which the alledged French Author affirms to be refuted by so manyexperiments made by this _Italian_ Philosopher, that it seems to him, thereis no place left for doubting, after so authentick a testimony. * * * * * _Advertisement. _ The _Reader_ of these _Transactions_ is desired to correct these _Errata_in _Number_ 8. _viz. _ page. 132. Line penult. Read _Wine_ for _Lime_; andpage 133. Line 10. Read _Thresher_ for _Trepher_, as some _Copies_ have it;and page 136. Line ult. Read _purifie_ for _putrifie_. * * * * * _LONDON, _ Printed for _John Martyn_ and _James Allestree_, Printers to the RoyalSociety. 1666. {163} * * * * * _Num. _ 10. PHILOSOPHICAL_TRANSACTIONS. _ * * * * * _Munday_, _March_ 12. 1665/6. * * * * * The Contents. _Observations continued upon the _Barometer_, or _Ballance of the Air_. A Relation concerning the _Earth-quake_ neer _Oxford_; together with some Observations of the sealed _Weatherglass_ and _Barometer_ thereupon by _Dr. Wallis_. A more full and particular Account of those Observations about _Jupiter_, that were mention'd in Numb. 8. An Account of some Books, lately publisht, _videl. _ Mr. _Boyles_ Hydrostatical Paradoxes; _Steno_ de Musculis & Gladulis; _De Graeff_ de Natura & Usu Succi Pancreatici. _ * * * * * _Observations continued upon the _Barometer_, or rather _Ballance of theAir_. _ These _Transactions_ being intended, _not only_ to be (by parcels) briefRecords of the Emergent Works and Productions in the Universe; Of theMysteries of Nature of later discoveries; And, of the growth of UsefulInventions and Arts; _but_ also, and chiefly, to sollicite in all partsmutuall Ayds and Collegiate endeavours for the farther advancement thereof:We shall begin this _Second_ year of our Publications in this kind (inwhich, for 3-moneths the Printing-presses were interrrupted by the publickCalamity) with a few more particular Observations upon the _Ballance of theAir_, as they are most happily invented and directed by Mr. _Boyle_; anddeserve to be prosecuted with care and diligence in all places. But it is to be premised, that the Worthy person, who was alledged as theAuthor of the Observations, delivered of this kind in the last of these_Tracts_ (Dr. _Beale_) gives notice, That {164} he did not pretend toexactness, but only to excite the carefulness of others in the severaldistant places, and chiefly such, as can have the assistance of a_Wheel-ballance_ perfectly filled: without both which aids he hopes not toobtain all the benefits and mysteries of this Invention. This being thus briefly intimated, the Account of the Observationsthemselves, as they were extracted out of a late Letter of the same Person, are, as followes: [Sidenote: __Hygroscopes_ are Instruments, to discover the degrees ofMoisture and Drought of the Air. _] 1. As I have fitted and filled the _Single Cane_, I can say in the general, That I have not yet found any such infallible Prognostick of these changesof weather, which do follow a long serenity, or setled weather. Andperchance in brighter Climats it may be constantly infallible. In these_Northern Islands_, the Clouds are so short, and narrow, and by ficklechanges are sometimes emptied upon us, sometimes so neer, as may make solittle variation in the weight of the whole Atmosphere of Air, as maysometimes deceive us, or smother and hide from us the causes of fixedness, or of changes. I wish I could see a good _Calendar_ or _Journal_ taken intaken in _Tangier_, and in some of our _Northern_ and most _Southern_ partsof _America_. I have store of _Hygroscopes_ of divers kinds; and I doremark them, and the sweatings of Marble, and as many other famedPrognosticks, as I can hear off; but can find nothing so neerly indicativeof the change of weather, as this _Ballance_. Those others are oftenchanged by Dews, which do not at all alter the _Ballance_, nor alter thestate of the weather: And the open Weather-glass is known to signifienothing at certainty, having a double obedience to two Masters, sometimesto the _Weight of the Air_, sometimes to _Heat_, as the service iscommanded. 2. And in further confirmation of this Note, I may adde to the former, Thatin _January_ last 1665/6, from the _fourth_, and more especially from the_seventh_ day, for many daies it continued very dark, so that all menexpected daily great rain; yet the _Mercury_ held very high, neer to thegreatest height; And though in those daies sometimes thick mists arose, andsome small rain fell, yet the _Quick-silver_ held at a great height: whichdid indicate to me, there could _then_ be no great change of weather. Asthe small rain fell, it yeilded somewhat, not much; and that does more{165} confirm the indication. And more lately, in very dark daies, I hadthe same confidence upon the same ground, and I was not disappointed. 3. Again, if the _Mercury_ ascends to a good height after the fall of rain(as sometimes, but less often it does) then I look for a setled serenity;but if it proceeds after rain in a descending motion, then I expect acontinuance of broken and showry weather. But in all, as I only say, _Forthe most part_, so I dare not positively declare it an affirmative result, but do refer it to the remarks of others. And this may explicate the Notes6. And 14 of _Num. _ 9. Into more clearness. 4. That we find the Weather and our Bodies more chill, cold, and drooping, when the _Mercury_ is lowest, and the Air lightest, besides other causes, Iguess, That as Air is to us the breath of life, as water is to Fishes; so, when we are deprived of the usual measure of this our food, 'tis the sameto us, as when the water is drawn ebb from Fishes. But I would much ratherbe instructed by others, then offer much in this kind. 5. The lowest descent of the _Mercury_ in all the time, since I haveobserved it, was _Octob. _ 26. 1665. In the Evening, when it was very nearat 27½ Inches. Which I find thus circumstanced with the weather in mynotes. _Oct. _ 25. Morning; _Mercury_ at 28½ Inch. Great storms and much rain. _Oct. _ 26. Morning; _Merc. _ at 28. Winds quiet, thick dark clouds. _Oct. _ 26. Evening; _Merc. _ at 27½. That day, and some daies following, the weather was variable, frequent rain, and as you see, the _Mercury_ lower, than usual. 6. Over the place, where this _Mercurial Cane_ stands, I have set a _Windvane_, with purpose of exactness, of a Streamer in Brass so large, andpointing to a Board indented in the Margin, that I can at a sure Level uponthe _Vane_, take every of the 32. Points of the Wind, half points, andquarter points, at good distance. Otherwise we may find our guesses muchdeceived, as the best guessers, upon trial, do acknowledge. And thisexactness may become the _Wheel-ballance_, which shews the minutestvariations almost beyond imagination. And thus any servant, at the approachof a thick Cloud, or other _Meteor_, higher or lower, or at the rising of astorm or fresh wind in the night, or day, may bring a report of the Weightof the Air, as certainly and almost as {166} easily, as of the Sun from the_Dial_ in a Sunshine. It were good to have an _Index_ of Winds, thatdiscover'd as well their Ascent and Descent, as their Side-coastings. * * * * * _A Relation concerning the late _Earthquake_ neer _Oxford_; together withsome Observations of the sealed Weatherglass, and the Barometer both uponthat _Phænomenon_, and in _General_. _ This Relation was communicated by the excellently learned Dr. _Wallis_, asfollows: On the 19. Of _January_ 1665. _Stylo Angliæ_ (or _Jan. _ 29. 1666. _stylonovo_) at divers places neer _Oxford_, was observed a small _Earthquake_(as at _Blechington, Stanton-St. Johns, Bril_, &c. ) towards evening. In_Oxford_ it self, I doe not hear, that it was observ'd to be an Earthquake;yet I remember about that time (whether precisely then or not; I cannotsay) I took notice of some kind of odde shaking or heaving I observed in mystudy, but did impute it to the going of Carts or Coaches, supposed to benot far off; though yet I did take notice of it, as a little differing fromwhat is usual on such occasions; (and wondered the more, that I did nothear any:) But not knowing, what else to refer it to, I thought no more ofit. And the like account I have had from some others in _Oxford_, who yetdid not think of an Earth-quake; it being a rare thing with us. Hearingafterwards of an Earthquake observed by others; I looked on my Notesconcerning my _Thermoscope_ and _Baroscope_, to see if any alterationconsiderable had then happened. My _Thermoscope_ consists of a round large Glass, containing about half apint or more; from whence issues a long Cylindrical neck of Glass, abouttwo foot and a half in length, and less than a quarter of an inch diameter;which neck was _hermetically_ sealed at the top, to exclude communicationwith the External Air; but before the sealing of it, the whole Glass wasfilled with _Spirit of Wine_ (tinged with _Cochineel_, to make it the morediscernable to the Eye) so warmed, that it filled the whole content of theGlass; but afterwards, as it cooled, did so subside, as to leave a voidspace in the upper part of the Neck. Which Instrument, so prepared, doth bythe rising or falling of the tinged liquor in the neck (consequent upon theexpanding or contracting of the whole liquor contained in it and the Ballbelow) give a very nice account of the Temperature of the Air, {167} as to_Heat_ or _Cold_: Even so nice, as that my being or not being in my Study Ifind to vary its hight sometimes almost a quarter of an inch. My _Baroscope_, I call another Instrument for estimating the _Weight_ or_Pressure_ of the Incumbent Air, consisting of a long _Glass-tube_ of about4. Foot in length, and about a quarter of an inch Bore: which tube(_hermetically_ sealed at the one end) being filled with Quicksilver(according to the _Torricellian_ Experiment) is inverted, so as to have theopen end of it immersed in Stagnant Quicksilver, contained in a largerGlass under it, exposed to the pressure of the outward Air: Out of whichopen end (after such immersion) the Quicksilver in the Tube being sufferedto run out, as much as it will, into the Stagnant Quicksilver, in whichthat mouth or open end is immersed, there is wont to remain (as is commonlyknown to those acquainted with this Experiment) a Cylinder of Quicksilversuspended in the Tube, about 28, 29, or 30. Inches high; measuring from thesurface of the Stagnant Quicksilver perpendicularly; (but more or less, within such limits, according as the Weight or Pressure of the Airincumbent on the External Stagnant Quicksilver exposed to it, is greater orless:) leaving the upper part of the Tube void. (Both which Instrumentsbeing the contrivance of the Honourable _Robert Boyle_, they are by himmore particularly described in his _Physico-Mechanical Experiments touchingthe Air, Exper. _ 17. And 18. And in his _Thermometrical Discourses_, premised to his _History of Cold_. ) Now, according to both these Instruments, having kept a daily _Register_ ofObservations for more than a whole year (saving when I have been for someshort time absent from home) I find my Notes for that day to be these. _January. _ |_Thermoscope. _|_Baroscope. _ 1665/6. Day. Hour. | inches. | inches. 19. 8. Morn. | 14-1/16. | 29-1/2. Hard frost. Close. 4. Even. | 14-3/8. | 29-1/4. Hard frost. Cloudy. 9. Even. | 14-3/4. | 29-3/4. Rain. Wind 20. 8. Morn. | 15-1/4. | 28-3/4. Sunshine. Wind. So that, there being in the morning (_January_ 19. ) a hard frost (whichbegan the day before about 4. Of the Clock in the {168} afternoon (_Jan. _18. ) and continued (with us) till about 5. Of the Clock in the afternoon ofthat day, _Jan_ 19. With some fierceness) and the weather, _Jan. _ 19. Beingin the morning, close; and cloudy all the day, with little of Sun-shine;the Liquor in the _Thermoscope_ was very little raised, by 4. Of the Clockafternoon, that is, but 5/16 of an inch (which, had the Sun shone, would, it's likely, have been near an Inch:) and after that time (or somewhatbefore) had there been no considerable change of weather, it would upon theSun's setting have fallen (and probably so it did, till about 5. Of theClock, though I took no Observation in the interim. ) But, contrary to whatwould have been expected, it was at 9. Of the Clock at night, higher by 1/8of an inch, than it had been at 4. Occasioned by the change of weather, theFrost suddenly breaking, with us, between 5. And 6. Of the Clock; aboutwhich time also it began to rain, and continued raining that Evening andgood part of the Night. And the next morning I found the Liquor yet higherby half an inch, _vid. _ 15¼ inches: (by reason of the Air that night beingso much warmer, than it had been the day before;) whereas commonly it isconsiderably lower in the morning, than over night. As to the _Baroscope_, for the Weight or Pressure of the Air; I find, thatfor the 11, l2, 13, 14, 15, 16, and 17. Dayes, the _Mercury_ in the Tube, was (by the ballancing Pressure of the incumbent Air on the stagnantQuicksilver, exposed to it) kept up to the height of near 30. Inches abovethe surface of the External Quicksilver, (though with some littlevariation, as 30, 29-15/16, 29-7/8, 29-13/16 but never so low, all thattime, as 29¾;) which is the greatest height I have know it at, (for I donot find that I have ever, till then, observed it to be, in my Glasses, full 30. Inches, though it have been very near it:) the Weather having beenalmost continually Foggy, or very thick Mists, all that time. _January_ 18. It came down to 29¾, in the forenoon; and afternoon, to 29-11/16. About thetime the frost began: And _Jan. _ 19. It was, at 8. In the morning, comedown to 29½; at 4. In the afternoon, to 29¼. But at 9. In the evening (whenthe Earth quake had intervened) it was risen half an inch, _vid. _ to 29¾. And, by the next morning, fallen again a whole inch, _vid. _ to 28¾; whichfall I attribute (at least in part) to the rain that fell in the night. This being what I observed out of my _Register_ of these Instruments, (which, if I had then thought of an Earthquake, I {169} should have morenicely watched) what I have further gathered from Reports, is to thispurpose. I hear, it was observed at _Blechington_, above 5. Miles to the _North_ of_Oxford_, and so along by _Bostol_, _Horton_, _Stanton-St. Johns_, and sotowards _Whately_, which is about 4. Miles _Eastward_ from _Oxford_. Not atall these places at the same time, but moving forward from _Blechington_towards _Whately_. For it was at _Stanton_ about 6. Of the Clock or later(as I understand from Mr. _Boyle_, who was there at that time;) but hadbeen at _Blechington_ a good while sooner. And I am told, that it was takennotice of by Doctor _Holder_ (a Member of our _Society_) who was then at_Blechington_, to be observed by those in the further part of the Garden, some very discernable time before it was observed by those in the House;creeping forward from the one place to the other. What other places in theCountry it was observed at, I have not been informed: but at _Oxford_(which, it seems, was about the skirts of it) it was so small, as wouldhave been hardly noted at all, had not the notice, taken of it abroad, informed us of it. Upon this Occasion, it will not be unseasonable to give some Generalaccounts of what I have in my _Thermoscope_ and _Baroscope_ observed. My _Thermoscope_, being fitted somewhat at adventures, I have found at thelowest to be somewhat more than 12. Inches high, in the fiercest time ofthe long Frost in the beginning of the last year 1665. And about 27. Incheshigh, at the highest, in the hottest time of the last Summer: (which Imention, that it may appear at what temperature in proportion, the Air wasat the time above-mentioned. ) But I must add withall, that this standingso, as never to be exposed to the Sun, but in a room, that has a windowonly to the North, it would have been raised much higher than 27. Inches, if it were put in the hot Sun-shine in Summer; this, as it is placed, giving therefore an account onely of the Temperature of the Air in_general_, not of the immediate heat of the Sun-shine. This Instrument, thus situated, when it is about 15. Inches, or lower, isfor the most part hard frost; but seldom a frost, if higher than 16. Yetthis I have often observed, that the Air by the _Thermoscope_ has appearedconsiderably colder (and the liquor lower) at sometimes when there is noFrost, than at some other times, when the Frost hath been considerablyhard. {170} In my _Baroscope_, I have never found the Quicksilver higher than 30. Inches, nor lower than 28. (at least, scarce discernably, not 1/16 of aninch higher than _that_, or lower than _this_;) which I mention, not onlyto shew the limits, within which I have observed mine to keep, _vid. _ full2 inches, but likewise as an Estimate of the Clearness of the Quicksilverfrom Air. For, though my Quicksilver were with good care cleansed from theAir; yet I find that which Mr. _Boyle_ useth, much better: for, comparinghis with mine at the same times, and both in _Oxford_, at no greatdistance; I find his Quicksilver to stand alwaies somewhat higher than mine(sometimes neer a quarter of an Inch;) which I know now how to give a moreprobable account off, than that my Quicksilver is either heavier than his;or else, that his is better cleansed from Air, (unless, possibly, thedifference of the Bore, or other circumstances of the Tube, may cause thealteration; mine being a taller Tube, and a bigger Bore, than his. ) Andupon like reason, as his stands higher than mine; so another less cleansedfrom Air, may at the same time be considerably lower, and consequentlyunder 28. Inches at the lowest. In _thick foggy_ weather, I find my Quicksilver to rise; which I adscribeto the heaviness of the Vapours in the Air. And I have never found ithigher, than in the foggy weather above-mentioned. In _Sunshiny_ weather it riseth also (and commonly the clearer, the more;)which, I think, may be imputed _partly_ to the Vapors raised by the Sun, and making the Air heavier; and _partly_ to the Heat, increasing theElastick or Springy power of the Air. Which latter I the rather add, because I have sometimes observed in Sunshiny weather, when there have comeClouds for some considerable time (suppose an hour or two) the Quicksilverhas fallen; and then, upon the Suns breaking out again, it has risen asbefore. In _Rainy_ weather, it useth to fall (of which the reason is obvious, because the Air is lightned, by so much as falls:) In _Snowy_ weather, likewise, but not so much as in _Rain_. And sometimes I have observed it, upon a _Hoar-frost_, falling in the night. [Sidenote: * _The Author of these Observations intends hereafter moreparticularly to observe, _from what points_ those Winds blow, that make theQuicksilver thus subside. _] For _Windy_ weather, I find it _generally_ to fall; and that moreuniversally, and more discernably, than upon Rain: (which I attribute tothe Winds moving the Air _collaterally_, and thereby not suffering it topress so much _directly_ downwards: the like of {171} which we see inswimming, &c. ) And I have never found it lower than in high Winds. * I have divers times, upon discerning my Quicksilver to fall without anyvisible cause at home, looked abroad; and found (by the appearance ofbroken Clouds, or otherwise) that it had rained not far off, though notwith us: Whereupon, the Air being then lightened, our heavier Air (where itrained not) may have, in part, discharged it self on that lighter. * * * * * _A more particular Account of those Observations about _Jupiter_, that werementioned in _Numb. 8_. _ Since the publishing of _Numb. _ 8. Of these _Transactions_, where, amongother particulars, some short Observations were set down touching both the_shadow_ of one of _Jupiter's Satellits_, passing over his Body, and that_Permanent Spot_, which manifests the Conversion of that Planet about hisown _Axis_; there is come to hand an _Extract_ of that Letter, which waswritten from _Rome_, about those Discoveries, containing an ample andparticular Relation of them, as they were made by the Learned _Cassini_, Professor of _Astronomy_ in the University of _Bononia_. That _Extract_, asit is found in the _French Journal des Scavans_ of _Febr. _ 22. 1666. Wethus _English_. Monsieur _Cassini_, after he had discovered (by the means of thoseExcellent Glasses of 50. _palmes_, or 35. _feet_, made by M. _Campani_) the_Shadows_, cast by the 4 Moons or _Satellits_ of _Jupiter_ upon his Diske, when they happen to be between the Sun and Him; after he had alsodistinguished their Bodies _upon_ the Diske of _Jupiter_; made the lastyear some Prædictions for the Months of _August_ and _September_, notingthe dayes and hours, when the Bodies of the said _satellits_ and their_Shadows_ should appear upon _Jupiter_, to the end that the Curious mightbe convinced of this matter by their own Observations. Some of these Prædictions have been verified not only at _Rome_, and inother places of _Italy_, but also at _Paris_ by M. _Auzout_, the mostCelebrated and the most Exact of our _Astronomers_; and in _Holland_, by M. _Hugens_. And we can now doubt no longer, of the rotation of the_Satellits_ about _Jupiter_, as the Moon turns about the Earth; norbelieve, that _Jupiter_ or his _Attendants_ have any other Light, thanthat, which they receive from the Sun; as some did {172} assure beforethese Observations. There remained to find by Experience, whether _Jupiter_did turn about his _Axis_, as many believe, that the _Earth_ turns abouther's. And although most _Astronomers_ had conjectur'd, it did so, eitherby this Analogy, or by other Congruities, yet it was much wish'd, that wemight be assured thereof by Observations. And this it is, for which we areobliged to M. _Cassini_, who, having by the advantage of the same Glassesdiscover'd several changes, as well in the three obscure _Belts_, commonlyseen in _Jupiter_, as in the rest of his _Diske_, and having also observedSpots in the midst of that _Planet_, and sometimes _Brightnesses_, such ashave bin formerly seen in the _Sun_, hath at length discover'd a _PermanentSpot_ in the _Northern_ part of the most _Southern_ Belt; by the meanswhereof, he hath concluded, that _Jupiter_ turns about his _Axis_ in 9. Hours, 56. Minutes, and makes 29. Whole circumvolutions in 12 dayes 4. Minutes of ours, and 360 in 149. Dayes. For he has found, that this _Spot_was not caused by the Shadow of any _Satellit_, as well by reason of itsSituation, as because it appeared, when there could be no Shadow. Besides, that its motion differed from that of the Shadows, which is almost equal, as well towards the Edges as towards the Middle of _Jupiter_: Whereas, onthe contrary, this _Spot_ hath all the accidents, that must happen to athing, which is upon the surface of a round Body moving; for example, tomove much more slowly towards the Edges, than towards the Middle, and topass over that part, which is in the middle of the Diske, equal to the halfof the _Diameter_, in the sixth part of the time, it takes to make thewhole revolution: he having seen this half pass'd over, in 99 or 100minutes just, as it must happen, supposing the whole circumrotation is madein 9. Hours 56. Minutes. He hath not yet been able to determine the Situation of the _Axis_, uponwhich this motion is made, because the _Belts_, according to which it ismade, have for some years appeared streight, though in the precedent years, other _Astronomers_ have seen them a little crooked: Which sheweth, thatthe _Axis_ of the diurnal motion of _Jupiter_ is a little inclined to theplain of the _Ecliptick_. But in time we may discover, what certainty thereis in this matter. [Sidenote: _These _Tables_ are not yet sent over, but, 'tis hoped, will be, ere long. _] After this excellent Discovery, he hath calculated many _Tables_, whereofhe gives the Explication and Use in the Letters by him addressed to theAbbot _Falconieri_. By the means of them, one may know, _when_ this _Spot_may be seen by us. For, having first {173} considered it in relation to the_Sun_, in respect whereof, its motion is regular, he considers the same inrelation to the _Earth_, where _We_ observe it; and shews by the means ofhis _Tables_, what is to be added or subtracted, to know, at what time thesaid _Spot_ is to come into the middle of _Jupiter_'s Diske, according ashe is Oriental or Occidental. He hath also considered it in relation to anunmovable point, which he has supposed to be the first point of _Aries_, because we thither refer here upon Earth the beginning of all the Celestialmotions, and _there_ is the _Primum mobile_, that one would imagine, if wewere in _Jupiter_, as we do here imagine Ours of 24. Hours. The Discovery is one of the best, that have been yet made in the Heavens;and those, that hold the Motion of the earth, find in it a full Analogy. For, _Jupiter_ turning about the Sun, does nevertheless turn about his_Axis_; and although he be much bigger than the Earth, he does neverthelessturn much more swiftly than it, since he makes more than two Turns, and athird part, for its one; and carries with him 4. Moons, as the Earth doesone. This Observation ought to excite all Curious persons to endeavour theperfecting of _Optick Glasses_, to the end that it may be discovered, whether the other _Planets_, as _Mars_, _Venus_ and _Mercury_, about whomno Moon hath as yet been discovered, do yet turn about their _Axes_, and inhow much time they do so; especially _Mars_, in whom some _Spot_ isdiscover'd, and _Venus_, wherein M. _Burattini_ hath signified from_Poland_, he has observ'd Inequalities, as in the Moon. It will be worth while, to watch for the seeing of _Jupiter_ again thisSpring, that this happy Observation may be confirmed in divers places, andendeavours used to make new ones. * * * * * _An Account of some Books, lately published. _ I. _Hydrostatical Paradoxes, made out by New Experiments (for the most partPhysical, and Easie) by the Honourable Robert Boyle. _ This Treatise, promised in _Numb. _ 8. Of these Papers, is now come forth: And wasoccasioned by the perusal of the Learned Monsieur _Paschalls_ Tract, _Ofthe Æquilibrium of Liquors_, and of the _Weight of the Air_: Of which twoSubjects, the _latter_ having been more clearly made out in _England_ byExperiments, which could not be made by Monsieur _Paschal_ and others, thatwanted the advantage of such Engines and Instruments, as have here beenfrequently made use {174} off; Our Noble Author insists most upon giving ushis thoughts of the former, _videl. _ the _Æquilibrium of Liquors_: WhichDiscourse consisting partly of _Conclusions_, and partly of _Experiments_, the _former_ seem to Him to be almost all of them consonant to thePrinciples and Laws of the _Hydrostaticks_; but as for the _latter_, theExperimental proofs, offered by M. _Paschall_ for his Opinions, are by ourAuthor esteemed such, that he confesses, he hath no mind to make use ofthem: for which he alledges more reasons than one; which, doubtless, willappear very satisfactory to Intelligent _Readers_. Wherefore, instead of the those _Paschalian_ Experiments, there is in this_Treatise_ deliver'd a far more Expeditious way, to make out, _not only_most of the _Conclusions_, agreed on these two Authors, _but_ others also, that M _Paschall_ mentions not: and that with so much more ease andclearness, that persons, but ordinarily versed in the common principles of_Hydrostaticks_, may readily apprehend, what is deliver'd, if they will butbring with them a due Attention, and Minds disposed to prefer Reason andExperience to Vulgar opinions and Authors. It not being our _Authors_ present Task, to deliver a Body of_Hydrostaticks_, but only some _Paradoxes_, which he conceives to beproveable by his New way of making them out, he delivers them in as manydistinct Propositions; after each of which, he endeavours, in a Proof, oran Explication, to show, both that it is true, and why it ought to be so. The _Paradoxes_ themselves (after a premised _Postulatum_) are these: 1. That in Water, and other Fluids, the Lower parts are pressed by theUpper. 2. That a lighter Fluid may gravitate or weigh upon a heavier. 3. That, if a Body, contiguous to the Water, be altogether, or in part, lower than the highest level of the said Water, the lower part of the Bodywill be pressed upward by the Water, that touches it beneath. 4. That in the Ascension of Water in Pumps, &c. There needs nothing toraise the Water, but a Competent weight of an External Fluid. 5. That the pressure of an External Fluid is able to keep an HeterogeneousLiquor suspended at the same height in several Pipes, though these Pipes beof very different Diameters. {175} 6. If a Body be placed under Water, with its uppermost Surface parallel tothe Horizon; how much Water soever there may be on this or that side abovethe Body, the direct pressure susteined by the Body (for we now considernot the Lateral nor the Recoyling pressure, to which the Body may beexposed, if quite environed with Water) is no more, than that of a Columnof water, having Horizontal Superficies of the Body for its Basis, and thePerpendicular depth of the Water for its height. And so likewise, If the Water, that leans upon the Body, be contained in Pipes open at bothends, the pressure of the Water is to be estimated by the weight of apillar of Water, whose Basis is equal to the lower Orifice of the Pipe(which we suppose to be parallel to the Horizon) and its height equal to aperpendicular, reaching thence to the top of the Water; though the Pipe bemuch inclined towards the Horizon, or though it be irregularly shap'd, andmuch broader in some parts, than the said Orifice. 7. That a Body, immersed in a Fluid, sustains a Lateral pressure from theFluid; and that increased, as the depth of the immersed Body, beneath theSurface of the Fluid, increaseth. 8. That Water may be made as well to depress a Body lighter than it self, as to buoy it up. 9. That, whatever is said of Positive Levity, a parcel of Oyl lighter thanWater, may be kept in Water without ascending in it. 10. That the cause of the Ascension of Water in Syphons, and of its flowingthrough them, may be explicated without having a recourse to Nature'sabhorrency of a _Vacuum_. 11. That a Solid Body, as ponderous as any yet known, though near the Topof the water it will sink by its own weight; yet if it be placed at agreater depth, than that of twenty times its own thickness; it will notsink, if its descent be not assisted by the weight of the incumbent Water. These are the _Paradoxes_, evinced by our Authour with much evidence andexactness, and very likely to invite Ingenious men to cultivate and to makefurther disquisitions in so excellent a part of Philosophy, as are the_Hydrostaticks_; and Art deserving great _Elogiums_, not only, upon theaccount of the _Theorems_ and _Problems_, which are most of them pure andhandsome productions of Reason, very delightful and divers of themsurprising, and besides, much conducing to the clear explication and {176}thorow-understanding of many both familiar and abstruse _Phænomena_ ofNature; but also, upon the score of its _Practical_ use, since thePropositions, it teaches, may be of great importance to Navigation, and tothose that inquire into the Magnitudes and Gravities of Bodies, as also tothem, that deal in Salt-works: Besides, that the _Hydrostaticks_ may bemade divers waies serviceable to _Chymists_, as the Author intimates, andintends to make manifest, upon several occasions, in his yet unpublishtpart of the _Usefulness of Natural and Experimental Philosophy_. These Propositions are shut up by two important _Appendixes_, whereof the_one_ contains an Answer to seven Objections by a late learned Writer, toevince, that the upper parts of water press not upon the lower; the_other_, solves that difficult _problem_, why _Urinators_ or _Divers_, andothers, who descend to the bottom of the Sea, are not oppressed with theweight of the incumbent water? where, among other solutions, _that_ isexamined, which occurs in a printed Letter of Monsieur _des Cartes_, but isfound unsatisfactory. II. _Nicolai Stenonis de Musculis & Glandulis Observationum Specimen; cumduabus Epistolis Anatomicis_. In the _Specimen_ it self, the Author, havingdescribed in _general_, both the _Structure_ and the _Function_ of the_Muscles_, applies that description to the _Heart_, to demonstrate that_that_ is also a _true Muscle_: Observing _first_, that in the substance ofthe _Heart_ there appears nothing but _Arteries, Veins, Nerves, Fibres, Membrans_; and that that, & nothing else is found in a _Muscle_; affirmingwithall, that which is commonly taught of the _Muscles_, and particularlyof the _Heart's Parenchyma_, as distinct from _Fibres_, is due, not to the_Senses_, but the _Wit_ of _Anatomists_: so that he will not have the_Heart_ made up of a substance peculiar to it self, nor considered as theprinciple of _Innate heat_, or of _Sanguification_, or of _vital spirits_. He observes _next_, that the _Heart_ performs the like _operation_ with the_Muscles_, to wit, to contract the Flesh; which action how it can have adifferent cause from that of the Contraction made in the _Muscles_, wherethere is so great a parity and agreement in the _Vessels_, he sees not. Andas for the _Phænomena_, that occur, of the _Motion_ of the Heart, heundertakes to explicate them all, from the _Ductus_ or _Position_ of the_Fibres_; but refers for the performance of this undertaking to another_Treatise_, he intends to publish. [Sidenote: __Conglobate_ Glanduls are called those, that do consist, as itwere, of one continued substance, having an _even_ superficies; whereofthere are many in the _Mesentery_, and in other places: contra distinguishtto those, that bear the name of _Conglomerate_ Glanduls, which are made upof several small Kernels, such as the _Pancreas_, the _SalivatingGlanduls_, &c. _] As to his Observations about _Glanduls_, he affirms, that he has been theFirst, that has discover'd that Vessel, which by him is call'd {177}_Salivare Exterius_, passing from the _Parotides_ (or the two chiefArteries that are on the right and left side neer the Throat) into theMouth, and conveying the _Spittle_: Where he also gives an account ofseveral other Vessels and Glanduls, some about the _Lips_; others under the_Tongue_; others in the _Pallate_ &c. To which he adds the Vessels of the_Eye-lids_, which have their root in the _Glanduls_ that are about theEyes, and serve for the _shedding of Tears_. He mentions also severalthings about the _Lymphatick vessels_, and is of opinion, that theknowledge thereof may be much illustrated by that kind of _Glanduls_ thatare called _Conglobatæ_, and by their _true_ insertion into the veins; themistake of the latter whereof, he conceives to have very much misled theNoble _Ludovicus de Bills_, notwithstanding his excellent method of_dissection_. And here he observes _first_, that all the _Lymphatickvessels_ have such a commerce with the _Glanduls_, that none of them isfound in the body, which either has not its origine _from_, or is inserted_into_ a _Glandule_: And _then_, that _Glanduls_ are a kind of _Strainers_, so form'd, that whilst the Blood passes out of the Arteries into the Veinsthrough the small _Capillary_ vessels, the _Serous_ parts thereof, beingfreed from the _Sanguineous_, are by vertue of the beat expell'd throughfit pores into the _Capilaries_ of the _Lymphaticks_, the direction of the_Nerves_ concurring. Of the two annex'd _Epistles_, the _First_ gives an account of thedissection of two _Raja's_ or _Skates_, and relates that the Author foundin the bellies of these Fishes a _Haddock_ of 1½ span long, and a _Sole_, a_Plaise_, and nine middle-sized _Sea crafishes_; whereof not only the threeformer had their flesh, in the fishes stomack, turn'd into a _fluid_, andthe Gristles or Bones into a _soft_ substance, but the _Crafishes_ hadtheir shels comminuted into very small particles, tinging here and therethe _Chyle_ near the _Pylorus_; which he judges to be done not so much bythe heat of the Fishes stomack, as by the help of some digesting juyce. Coming to the _Uterus_ of these Fishes, he takes occasion to examine, withwhat ground several famous _Naturalists_ and _Anatomists_ have affirm'd, that Eggs are the _uterus_ exposed or ejected out of the body of theAnimal. Taking a view of their _Heart_, he there finds but _one_ ventricle, and discourses of the difficulty arising from thence. As for the _Lungs_, he saw no clearer footsteps of them in these, than he had done in otherFishes: but within the mouth he trac'd several _gaping fissures_, and foundthe recesses of the _Gills_ so form'd, that the water taken in at themouth, being let out by these dores, cannot by them re-enter, by reason ofa skin outwardly passing over every hole, and covering it. Where heintimates, that though Fishes have not _true_ Lungs, yet they want not a_Succedaneum_ thereto, to wit, the _Gills_; and if _water_ may be toFishes, what _Air_ is to terrestrial Animals, for Respiration: affecting, that whereas nothing is so necessary for the conservation of Animal life asa reciprocal Access and Recess of the _Ambient_ to the sanguineous vessels, tis all one, whether that be done by receiving the Ambient _within_ thebody, or by its gentle passing _by_ the _Prominent_ vessels of the _Gills_. The other _Epistle_, contains some Ingenious Observations, touching theway, by which the Chicken, yet in the shell, is nourish't, _videl. _ not bythe conveyance of the _Yolk_ into the _Liver_ by the _Umbilical_ vessels, nor into the _Stomack_ by the {178} _Mouth_, but by a Peculiar _ductus_, byhim described, into the _Intestins_, where, according to his alledgedexperience, it is turn'd into _Chyle_: which he affirms, he hathdiscover'd, by taking an Egge from under a brooding Hen, when the Chickenwas ready to break forth, and when he was looking for the passage of the_Yolk_, out of its integument into the _Liver_, by finding it pass thenceinto the _Intestins_, as he found the _White_ to do by the _mouth_ into the_belly_. Whence he inclines to infer, that, since every _fætus_ takes in atthe mouth the liquor it swims in, and since the Chicken receives the_white_ of the Egge into the _mouth_, and the _yolk_ by the new discover'd_ductus_ into the _Intestins_, it cannot be certainly made out, that a_part_ of the _Chyle_ is conveyed into the _Liver_, before it passes intothe _Heart_; Exhorting in the mean time the _Patrons_ of the _Liver_, thatthey would produce Experiments to evince their Ratiocinations. III. _Regneri de Graeff, de Succi Pancreatici Natura & usu, ExercitatioAnatomico-medica. _ In this Tract, the Industrious Author, after he hasenumerated the various opinions of _Anatomists_ concerning the use of thatkernelly substance; call'd _Pancreas_ (in _English_, the _Sweetbred_)endeavours to prove experimentally that this _Glandule_ was not form'd byNature, to separate any _Excrementitious_ humor, and to convey it into the_Intestins_, but to prepare an _useful_ juyce out of the Blood and AnimalSpirits, of a somewhat _Acid_ taste, and to carry the same into the Gut, call'd _Duodenum_, to be there mixt with the Aliment, that has been in somedegree already fermented in the Stomack, for a further fermentation, to beproduced by the conflux of the said acid _Pancreatick_ juyce and some_Bilious_ matter, abounding with volatile Salt, causing an Effervescence;which done, that juyce is, together with the purer part of the nourishment, carried into the _Milkie_ veins, thence into the _common receptacle_ of the_Chyle_ and _Lymphatick liquor_, and so through the _ductus Thoracicus_into the right Ventricle of the Heart. This Assertion, first advanced (saith the _Author_) partly by _GothofredusMobius_, partly by _Franciscus de le Boe Sylvius_, he undertakes to proveby experiments; which, indeed, he has with much industry, tried uponseveral Animals, to the end that he might collect some of this juyce of the_Pancreas_ for a taste: which having at last obtained, and found itsomewhat _acid_, he thereupon proceeds to deliver his opinion both of the_constitution_ and quantity of this _Succus_ in _healthy_ Animals, and thevices thereof, in the _unhealthy_: deriving most diseases _partly_ from itstoo great Acidity, or from its saltness, or harshness; _partly_ from itspaucity or redundancy: but especially, endeavouring to reduce from thence, as all _intermittent Feavers_ (of all the _Phænomena_ whereof he venturesto assign the causes from this _Hypothesis_) so also the _Gout, Syncope's, Stranguries, Oppilations, Diarrhæas, Dysenteries, Hysterical_ and _Colickpassions_, &c. All which he concludes with mentioning the waies andremedies to cure the manifold peccancy of this juyce by Evacuations andAlterations. This seeming to be a _new_ as well as a _considerable_ discovery, it ishop'd, that others will by this intimation be invited to prosecute the sameby further experiments, either to confirm what this Author has started, iftrue, or to rectifie it, if he be mistaken. * * * * * _NOTE. _ In _Fig. _ 1. Of _Num. _ 9 of these Tracts the Graver hath placed the bended_end_ of the _Springing Wire_ C F, above the _Wire-staple_ B, between itand the _Ring_ E, of the _Weight_ D; whereas _that_ end should have been soexpressed, as to pass _under_ the _Wire-staple_, betwixt its two Wires, into the said _Ring_. * * * * * _London_, Printed for _John Martyn_, and _James Allestry_, Printers to theRoyal Society. 1666. {179} * * * * * _Num. _ 11. PHILOSOPHICAL_TRANSACTIONS. _ * * * * * _Munday_, _April. _ 2. 1666. * * * * * The Contents. _A Confirmation of the former Account, touching the late _Earth-quake_ near _Oxford_, and the Concomitants thereof, by Mr. _Boyle_. Some Observations and Directions about the _Barometer_, communicated by the same Hand. General Heads for a _Natural History_ of a Country, small or great, proposed by the same. An Extract of a Letter, written from _Holland_, about _Preserving Ships from being Worm-eaten_. An Account of Mr. _Boyle's_ lately publish't Tract, entituled, _The Origine of Forms and Qualities_, illustrated by Considerations and Experiments. _ * * * * * _A Confirmation of the former Account touching the late _Earth-quake_ near_Oxford_, and the Concomitants thereof. _ This Confirmation came from the Noble Mr. _Boyle_ in a Letter, to the_Publisher_, as followeth: [Sidenote: * _See_ Num. 10. Phil. Transactions p. 166-171; _at the time ofthe printing whereof, this Relation of Mr. _ Boyle _was not yet come tohand. _] As to the _Earth-quake_, your curiosity about it makes me sorry, that, though I think, I was the first, that gave notice of it to several of the_Virtuosi_ at _Oxford_; yet the Account, that I can send you about it, isnot so much of the _Thing_ it self, {180} as of the _Changes of the Air_, that accompanied it. To inform you of which, I must relate to you, thatriding one Evening somewhat late betwixt _Oxford_ & a Lodging, I have at aplace, 4 miles distant from it, the weather having been for a pretty whileFrosty, I found the Wind so very cold, that it reduced me to put on somedefensives against it, which I never since, nor, if I forget not, all theforegoing part of the Winter was obliged to make use off. My unwillingnessto stay long in so troublesome a Cold, which continued very piercing, tillI had got half way home-ward, did put me upon galloping at no very lasyrate; and yet, before I could get to my Lodgings, I found the Wind turned, and felt the Rain falling; which, considering the shortness of the time, and that this Accident was preceded by a setled Frost, was surprising tome, and induced me to mention it at my return, as one of the greatest andsuddainest Alterations of Air, I have ever observ'd: And what changes Ifound, have been taken notice of in the _Gravity_ of the _Atmosphere_ atthe same time by that Accurate Observer * Dr. _Wallis_, who then suspectednothing of what follow'd; as I suppose, he has ere this told you himself. Soon after, by my guess about an hour, there was a manifest _Trembling_ inthe House where I was (which stands high in comparison of _Oxford_. ) But itwas not there so great, but that I, who chanced to have my thoughts busiedenough on other matters, than the weather, should not have taken notice ofit as an _Earth-quake_, but have imputed it to some other cause, if one, that you know, whose hand is employed in this Paper, and begins to be adiligent observer of Natural things, had not advertis'd me of it; as beingtaken notice of by him and the rest of the people of the House. And soonafter there hapned a brisk Storm: whereupon I sent to make inquiry at aplace call'd _Brill_, which standing upon a much higher ground, I supposedmight be more obnoxious to the effects of the _Earth-quake_ (of which, hadI had any suspition of it, my having formerly been in one neer the _LacusLemanus_, would have made me the more observant:) But the person I sent to, being {181} disabled by sickness to come over to me (which he promis'd todo, as soon as he could) writ me only a _Ticket_, whose substance was, Thatthe _Earth-quake_ was there much more considerable, than where I lodged, and that at a Gentlemans house, whom he names (the most noted Person, itseems, of the neighbourhood) the House trembled very much, so as to makethe Stones manifestly to move to and fro in the Parlour, to the greatamazement and fright of all the Family. The Hill, whereon this _Brill_stands, I have observ'd to be very well stor'd with Mineral substances ofseveral kinds; and from thence I have been inform'd by others, that thisEarth-quake reach'd a good many miles; but I have neither leasure, norinclination to entertain you with uncertain reports of the Extent and otherCircumstances, especially since a little further time an inquiry may enableme to give you a better warranted account. * * * * * _Some Observations and Directions about the _Barometer_, communicated bythe same Hand, to the _Author_ of this _Tract_. _ These shall be set down, as they came to hand in another Letter; _videl. _ [Sidenote: * _See _Num. 9_. Of the _Phil. Transact_. P. 159 the last_paragraph_. _] As to the _Barometrical_ Observations (as for brevities sake I use to callthem) though you * guessed aright, that, when I saw those of the Learnedand Inquisitive Dr. _Beale_, I had not Mine by me, (for I left them, someyears since, in the hands of a _Virtuoso_, nor have I now the leasure tolook after those Papers;) yet since by the Communication, you have madepublick, 'tis probable, that divers Ingenious men will be invited toattempt the like Observations, I shall (notwithstanding my present haste)mention to you some particulars, which perhaps will not appearunseasonable, that came into my mind upon the reading of what you havepresented the Curious. [Sidenote: * _Some whereof have been since invited by the _Publisher_, togive their concurrence herein_. ] When I did, as you may remember, some years agoe, publickly express anddesire that some Inquisitive men would {182} make _Baroscopical_Observations in several parts of _England_ (if not in forrain Countries *also;) and to assist them, to do so, presented some of my Friends with thenecessary Instruments: The declared reason of my desiring thisCorrespondence was (among other things) that by comparing Notes, _theExtent of the Atmospherical Changes, in point of Weight, might be thebetter estimated_. But not having hitherto received some account, that Ihoped for, I shall now, without staying for them, intimate thus much toyou: That it will be very convenient, that the Observers take notice notonly of the _day_, but as near as they can, of the _Houre_ wherein theheight of the _Mercurial Cylinder_ is observ'd: For I have often found, that within less than the compass of one day, or perhaps half a day, theAltitude of it has so considerably vary'd, as to make it in many casesdifficult, to conclude any thing certainly from Observations, that agreebut in the day. It will be requisite also, that the Observers give notice of the_Scituation of the place_, where their _Barometers_ stand, not only, because it will assist men to Judge, whether the Instruments were duelyperfected, but principally, because, that though the _Baroscope_ be good(nay, because it is so) the Observations will much disagree, even when the_Atmosphere_ is in the same state, as to Weight, if one of the Instrumentsstand in a considerably higher part of the Countrey, than the other. To confirm _both_ the foregoing admonitions, I must now inform you, that, having in these parts two Lodgings, the one at _Oxford_, which you knowstands in a bottom by the _Thames_ side, and the other at a place fourmiles thence, seated upon a moderate _Hill_, I found, by comparing two_Baroscopes_, that I made, the one at _Oxford_, the other at _Stanton St. Johns_, that, though the former be very good, and have been noted for such, during some years, and the latter was very carefully fill'd; yet by reason, that in the _Higher_ place, the incumbent part of the _Atmosphere_ must belighter, than in the _Lower_, there is almost {183} always between 2 and 3Eights of an Inch difference betwixt them: And having sometimes order'd myservants to take notice of the Disparity, and divers times carefullyobserv'd it my self, when I pass'd to and fro between _Oxford_ and_Stanton_, I generally found, that the _Oxford Barometer_ and the _other_, did, as it were by common consent, rise and fall together so, as that inthe former the _Mercury_ was usually 3/8 higher, than in the latter. Which Observations may teach us, that the Subterraneous steams, whichascend into the Air, or the other Causes of the varying Weight of the_Atmosphere_, do, many times, and at least in some places, uniformly enoughaffect the Air to a greater height, than, till I had made this tryall, Idurst conclude. But, as most of the _Barometricall_ observations are subject to exception, so I found the formerly mentioned to be. For (to omit lesser variations)riding one evening from _Oxford_ to _Stanton_, and having, before I tookhorse, look't on the _Baroscope_ in the former of these 2. Places, I wassomewhat surprised, to find at my comming to the latter, that in places nofarther distant, and notwithstanding the shortness of the time (which wasbut an hour and a half, if so much) the _Barometer_ at _Stanton_ was shortof its usual distance from the _other_, near a quarter of an _Inch_, though, the weather being fair and calm, there appear'd nothing of manifestchange in the Air, to which I could adscribe so great a Variation; andthough also, since that time, the _Mercury_ in the two Instruments hath, for the most part, proceeded to rise and fall as before. And these being the only Observations, I have yet met with, wherein_Baroscopes_, at some _Distance of Place_, and _Difference of Height_, havebeen compar'd (though I cannot now send you the Reflexions, I have elsewhere made upon them;) as the opportunity I had to make them my self, rendred them not unpleasant to me, so perhaps the Novelty will keep themfrom being unwelcome to you. And I confess, I have had some flyingsuspicions, that the odd _Phænomena_ of the _Baroscope_, which havehitherto more pos'd, than instructed us, may in time, if a {184} competentnumber of Correspondents do diligently prosecute the Inquiries (especiallywith _Baroscopes_, accommodated with Mr. _Hooks_ ingenious additions) makemen some _Luciferous_ discoveries, that possibly we do not yet dream off. [Sidenote: * _This hath been inquired into, and is found, that severalAccurate and Curious persons (as the Most Noble _President of the RoyalSociety_, the Lord Viscount _Brounker_, _Doctor Beale_, _Mr. Hook_ _&c. _)have observed the same. _] I know not, whether it will be worth while to add, that since I was oblig'dto leave _London_, I have been put upon so many lesser removes, that I havenot been able to make _Baroscopical_ Observations with such a constancy, asI have wished, but, as far as I remember, the _Quick-silver_ has been forthe most part, so high, as to invite me to take notice of it; and to desireyou to do me the favour to inquire among your correspondents whether theyhave observ'd the same thing. * For, if they have, this lasting (though notuninterrupted) Altitude of the _Quick-silver_, happening, when the Seasonsof the year have been extraordinary dry (so much as to become a grievance, and to dry up, as one of the late _Gazettes_ informs us, some springs near_Waymouth_, that used to run constantly) it may be worth inquiry, whetherthese obstinate Droughts, may not be cleaving of the ground too deep, andmaking it also in some places more porous and as it were, spungy, give amore copious Vent, than is usual, to subterraneal steams, which adscendinginto the Air, increase the gravity of it. The inducements I have to proposethis inquiry, I must not now stay to mention. But perhaps, if theObservation holds, it may prove not useless in reference to some Diseases. [Sidenote: * _See Number 9. _Phil. Transact. _ p. 157. 5. 8 & 9. Where theWord, _Generally_, signifies no more, than _for the most part_. _] Perhaps it will be needless to put you in mind of directing those_Virtuosi_, that may desire your Instructions about _Baroscopes_, to setdown in their Diarys not only the day of the month, and the hour of theday, when the _Mercuries_ height is taken, but (in a distinct _Columne_)the weather, especially the Winds, both as to the Quarters, whence theyblow (though that be not always so easy nor necessary, ) and as to theViolence or Remisness, wherewith they blow. For, though it be moredifficult, {185} than one would think, to settle any general rule about therising and falling of the _Quick-silver_; yet in these parts one of those, that seem to hold oftnest, is, * that when high winds blow, the _Mercury_is the lower; and yet that it self does sometimes fail: For, this very day(_March_ 3. ) though on that hill, where I am, the somewhat Westerly Windshave been blustering enough, yet ever since morning the _Quick-silver_ hasbeen rising, and is now risen near 3/8 of an _Inch_. I had thoughts to add something about another kind of _Baroscope_ (butinferiour to that in use) whereof I have given some intimation in one ofthe _Præliminaries_ to the _History of Cold_. But you have already too muchof a letter, and my occasions, &c. [Sidenote: * _Dr. _Beale_ concurs with this Observation, when he saith, ina late _Letter_ of _March 19_. To his Correspondent in _London_;_ By changeof Weather and Wind, the _Mercury_ is sunk more than an Inch, since I wroteto you on _Munday_ last. _March_ 12. This last night, by Rain and Southwind, 'tis sunk _half an Inch_. ] _So far that Letter. _ Since which time, another from the same NobleObserver intimates, That, as for that cause of the height of the_Quick-silver_ in Droughts, which by him is suspected to be the elevationof steams from the _Crust_ or Superficial parts of the Earth, which bylittle and little may add to the Weight of the _Atmosphere_, being not, asin other seasons, carried down from time to time by the falling Rain, itagrees not ill with what he has had since occasion to observe. For, whereasabout _March_ 12^{th}, at _Oxford_, The _Quick-silver_ was higher, than, for ought he knew, had been yet observ'd in _England_, viz. Above 5/16above 30. _Inches_, upon the first considerable showers, that haveinterrupted our long Drought, as he affirms, he foretold divers hoursbefore that the _Quick-silver_ would be very low, (a blustering Windconcurring with the Rain) so he found it at _Stanton_ to fall 3/8 beneath29. _Inches_. * {186} * * * * * _General Heads for a _Natural History of a Countrey_, Great or Small, imparted likewise by Mr. _Boyle_. _ It having been already intimated (_Num. 8 of Phil. Transact. _ p. 140. 141. )that divers _Philosophers_ aime, among other things, at the Composing of agood Natural History, to superstruct, in time, a _Solid_ and _Useful_Philosophy upon; and it being of no slight importance, to be furnisht withpertinent Heads, for the direction of Inquirers; that lately named_Benefactour to Experimental Philosophy_, has been pleased to communicate, for the ends abovesaid, the following _Articles_, which (as himself didsignifie) belong to one of his _Essays_ of the unpublisht part of the_Usefulness of Nat. And Experimen. Philosophy_. But first he premises, that what follows, is design'd only to point at themore _General_ heads of Inquiry, which the proposer ignores not to beDivers of them very comprehensive, in so much, that about some of the_Subordinate_ subjects, perhaps too, not the most fertile, he has drawn up_Articles_ of inquisition about particulars, that take up near as muchroom, as what is here to be deliver'd of this matter. The _Heads_ themselves follow; The things, to be observ'd in such a History, may be variously (and almostat pleasure) divided: As, into _Supraterraneous, Terrestrial_, and_Subterraneous_; and otherwise: but we will at present distinguish theminto those things, that respect the _Heavens_, or concern the _Air_, the_Water_, or the _Earth_. 1. To the _First_ sort of Particulars, belong the Longitude and Latitude ofthe Place (that being of moment in reference to the observations about theAir &c. ) and consequently the length of the longest and shortest days andnights, the Climate, parallels &c. What fixt starrs are and what not seenthere: What Constellations 'tis said to be subject to? Whereunto may beadded other Astrological matters, if they be thought worth mentioning. {187} 2. About the _Air_ may be observ'd, its Temperature, as to the first fourQualities (commonly so call'd) and the Measures of them: its Weight, Clearness, Refractive power: its Sublety or Grossness: its abounding with, or wanting an _Esurine_ Salt: its variations according to the seasons ofthe year, and the times of the day; What duration the several kinds ofWeather usually have: What _Meteors_ it is most or least wont to breed; andin what order they are generated; and how long they usually last:Especially, what Winds it is subject to; whether any of them be stated andordinary, &c. What diseases are Epidemical, that are supposed to flow fromthe Air: What other diseases, wherein _that_ hath a share, the Countrey issubject to; the Plague and Contagious sicknesses: What is the usualsalubrity or insalubrity of the Air; and with what Constitutions it agreesbetter or worse, than others. 3. About the _Water_, may be observ'd, the Sea, its Depth, degree ofSaltness, Tydes, Currents, &c. _Next_, Rivers, their Bigness, Length, Course, Inundations, Goodness, Levity (or their Contraries) of Waters, &c. _Then_, Lakes, Ponds, Springs, and especially Mineral waters, their Kinds, Qualities, Vertues, and how examined. To the _Waters_ belong also _Fishes_, what kinds of them (whether Salt or Fresh-water fish) are to be found inthe Country; their Store, Bigness, Goodness, Seasons, Haunts, Peculiaritiesof any kind, and the wayes of taking them, especially those that are notpurely _Mechanical_. 4. In the _Earth_, may be observed, 1. _It self. _ 2. Its _Inhabitants_, and its _Productions_, and these _External_, and _Internal_. _First_, in the Earth _it self_, may be observ'd, its dimensions, scituation, East, West, North, and South: its Figure, its Plains, andValleys, and their Extent; its Hills and Mountains, and the height of thetallest, both in reference to the neighbouring Valleys or Plains, and inreference to the Level of the Sea: As {188} also, whether the Mountains lyescattered, or in ridges, and whether those run North and South, or East andWest, &c. What Promontories, fiery or smoaking Hills, &c. The Country has, or hath not: Whether the Country be coherent, or much broken into Ilands. What the Magnetical Declination is in several places, and the Variations ofthat Declination in the same place (and, if either of those be veryconsiderable, then, what circumstances may assist one to guess at theReason as Subterraneal fires, the Vicinity of Iron-mines, &c. ) what theNature of the Soyle is, whether Clays, Sandy, &c. Or good Mould; and whatGrains, Fruits, and other Vegetables, do the most naturally agree with it:As also, by what particular Arts and Industries the Inhabitants improve theAdvantages, and remedy the Inconveniences of their Soyl: What hiddenqualities the Soyl may have (as that of _Ireland_, against Venemous Beasts, &c. ) _Secondly_, above the ignobler _Productions_ of the Earth, there must be acareful account given of the _Inhabitants_ themselves, both _Natives_ and_Strangers_, that have been long settled there: And in particular, theirStature, Shape, Colour, Features, Strength, Agility, Beauty (or the want ofit) Complexions, Hair, Dyet, Inclinations, and Customs that seem not due toEducation. As to their Women (besides the other things) may be observedtheir Fruitfulness or Barrenness; their hard or easy Labour, &c. And bothin Women and Men must be taken notice of what diseases they are subject to, and in these whether there be any symptome, or any other Circumstance, thatis unusual and remarkable. As to the _External_ Productions of the Earth, the Inquiries may be such asthese: What Grasses, Grains, Herbs, (Garden and Wild) Flowers, Fruit-trees, Timber-trees (especially any Trees, whose wood is considerable) Coppices, Groves, Woods, Forrests, &c. The Country has or wants: What peculiaritiesare observable in any of them: What Soyles they most like or dislike; andwith what Culture they thrive best. What _Animals_ the Country has orwants, both as to wild Beasts, Hawks, and other Birds of Prey; and as toPoultrey, and {189} Cattle of all sorts, and particularly, whether it haveany _Animals_, that are not common, or any thing, that is peculiar inthose, that are so. The _Internal_ Productions or Concealments of the Earth are here understoodto be, the riches that ly hid under the Ground, and are not alreadyreferr'd to other Inquiries. Among these _Subterraneal_ observations may be taken notice of, what sortsof Minerals of any kind they want, as well as what they have; _Then_, whatQuarries the Country affords, and the particular conditions both of theQuarries and the Stones: As also, how the Beds of Stone lye, in referenceto North and South, &c. What Clays and Earths it affords, asTobacco-pipe-clay, Marles, Fullers-earths, Earths for Potters wares, Bolus's and other medicated Earths: What other Minerals it yields, asCoals, Salt-Mines, or Salt-springs, Allom, Vitrial, Sulphur, &c. WhatMettals the Country yields; and a description of the Mines, their number, scituation, depth, signs, waters, damps, quantities of ore, goodness ofore, extraneous things and ways of reducing their ores into Mettals, &c. To these General Articles of inquiries (saith their _Proposer_) should beadded; 1 _Inquiries_ about _Traditions_ concerning all particular things, relating to that Country, as either peculiar to it, or at least, uncommonelsewhere, 2 _Inquiries_, that require _Learning_ or _Skill_ in theAnswerer: to which should be subjoyned _Proposals_ of ways, to enable mento give Answers to these more difficult inquiries. _Thus far_ our Author, who, as he has been pleased to impart these_General_ (but yet very _Comprehensive_ and greatly _Directive_) Articles;so, 'tis hoped from his own late intimation, that he will shortly enlargethem with _Particular_ and _Subordinate_ ones. These, in the mean time, were thought fit to be publisht, that the Inquisitive and Curious, might, by such an Assistance, be invited not to delay their searches of matters, that are so highly conducive to the improvement of _True Philosophy_, andthe wellfare of _Mankind_. {190} * * * * * _An Extract of a Letter, Written from _Holland_, about _Preserving of Shipsfrom being Worm-eaten_. _ This _Extract_ is borrowed from the _French journal des Scavans_ of _Febr. _15. 1666. And is here inserted, to excite Inventive heads _here_, toovertake the Proposer in _Holland_. The letter runs thus: Although you have visited our Port (_Amsterdam_) I know not whether youhave noted the ill condition, our ships are in, that return from the_Indies_. There is in those Seas a kind of small worms, that fastenthemselves to the Timber of the ships, and so pierce them, that they takewater every where; or if they do not altogether pierce them thorow, they soweaken the wood, that it is almost impossible to repair them. We have atpresent a Man here, that pretends to have found an admirable secret toremedy this evil. That, which would render this secret the more important, is, that hitherto very many ways have been used to effect it, but withoutsuccess. Some have imployed Deal, Hair and Lime, &c. And therewith linedtheir ships; but, besides that this does not altogether affright the worms, it retards much the ship's Course. The _Portugals_ scorch their ships, insomuch that in the quick works there is made a coaly crust of about an_Inch_ thick. But as this is dangerous, it happening not seldom, that thewhole vessel is burnt; so the reason why worms eat not thorow _Portugal_ships, is conceived to be the exceeding hardness of the Timber, employed bythem. We expect with impatience the nature and effect of this Proposition. Manyhave already ventur'd to give their thoughts concerning it. Some say, thereneeds no more, but to build Ships of a harder kind of Wood, than the usual. Others having observed, that these Worms fasten not to a kind of wild_Indian_ Pear-tree, which is highly bitter, do thereupon {191} suggest, that the best Expedient would be, to find out a Wood having that quality. But certainly there being now no Timber, fit for Ships, that is not known, 'tis not likely that any will be found either more hard, or more bitter, than that, which has been hitherto employed. Some do imagine, that theProposer will, by certain _Lixiviums_, give to the ordinary Wood such aquality and bitterness, as is found in the already mention'd _Indian_Pear-tree. But this also will hardly succeed, since it will be requisitenot only to make _Lixiviums_, in great quantities at an easie rate, andstrong enough to penetrate the thick sides of a Ship, but also to make themdurable enough, not to be wash't out by the Sea. Yet notwithstanding, inthese matters one ought to suspend on's judgement, untill experience doshew, what is to be believed of them. _So far the Extract. _ To which it may perhaps not be unseasonable to add, that a very worthy person in _London_, suggests the Pitch, drawn out of Seacoles, for a good Remedy to scare away these noysome insects. * * * * * _An Account of a Book, very lately publish't, entituled, _The Origine ofForms and Qualities_, illustrated by Considerations and Experiments, by theHonourable _Robert Boyle_. _ This Curious and Excellent Piece, is a kind of _Introduction_ to the_Principles_ of the _Mechanical Philosophy_, explicating, by veryConsiderable Observations and Experiments, what may be, according to suchPrinciples, conceived of the _Nature and Origine of Qualities and Forms_;the knowledge whereof, either makes or supposes the Fundamental and Usefulpart of _Natural Philosophy_. In doing of which, the Author, to have hisway the clearer, writes rather for the _Corpuscularian_ Philosophers (as heis pleased to call them) in _General_, than any {192} _Party_ of them, keeping himself thereby disengaged from adopting an _Hypothesis_, in whichperhaps he is not so throughly satisfied, and of which he does not conceivehimself to be necessitated to make use here; and accordingly forbearing toemploy Arguments, that are either grounded on, _or_ suppose _Atoms_, _or_any _Innate Motion_ belonging to them; _or_ that the Essence of Bodiesconsists in Extension; _or_ that a _Vacuum_ is impossible; _or_ that thereare such _Globuli Cælestes, or_ such a _Materia Subtilis_, as the_Cartesians_ imploy to explicate most of the _Phænomena_ of Nature. The _Treatise_ consisting of a _Speculative_, and an _Historical_ part, theAuthor, with great modesty leaves the _Reader_ to judge; _Whether_ in the_First_ part he hath treated of the _Nature_ and _Origine of Forms andQualities_ in a more Comprehensive way, than others; _Whether_ he has byfit Examples, and other means, rendred it more intelligible, than they havedone: _Whether_ he has added any considerable number of Notions andArguments towards the compleating and confirming of the proposed_Hypothesis_: _Whether_ he has with reason dismissed Arguments unfit to berelied on; and _Whether_ he has proposed some Notions and Arguments sowarily, as to keep them from being liable to Exceptions and Evasions, whereto they were obnoxious, as others have proposed them. And, as to the_Second_ and _Historical_ part, he is enclin'd to believe that the _Reader_will grant, he hath done that part of _Physicks_, he is treating of, someservice, by strengthning the doctrines of the _New Philosophy_ (as 'tiscall'd) by such particular Experiments, whose Nature and Novelty willrender them as well Acceptable as Instructive. The _summe_ of the _Hypothesis_, fully and clearly explicated in the_First_ Part, is this; That all Bodies are made of _one Catholick matter_, common to them all, anddiffer but in _Shape, Size, Motion_ or _Rest_, and _Texture_ of the smallparts, they consist off; from which {193} Affections of Matter, the_Qualites_, that difference particular Bodies, result: whence it may berationally concluded, that one kind of Bodies may be transmuted intoanother; _that_ being in effect no more, than that one Parcel of theUniversal Matter, wherein all Bodies agree, may have a _Texture_ producedin it, like the _Texture_ of some other Parcel of Matter, common to themboth. To this _Hypothesis_, is subjoin'd an Examination of the _Scholastick_opinion of _Substantial Forms_; where the Author, _first_, States theControversie; _next_, gives the Principal reasons, that move him to opposethat Opinion; _then_, answers the Main arguments employed to evince it;_further_, assigns both the _First_ Cause of Forms (_God_;) and the Grand_Second_ Cause thereof (_Local Motion_:) and _lastly_, proves the_Mechanical_ Production of _Forms_; grounding his proof, _partly_ upon theManner, by which such a _Convention of Accidents_, as deserve to pass for a_Form_, may be _produced_; as that the Curious Shapes of _Salts_ (believedto be the admirablest Effects and strongest Proofs of _Substantial Forms_)may be the Results of _Texture_; _Art_ being able to produce Vitriol, aswell as _Nature_: _partly_, upon the possibility of _Reproducing_ Bodies byskill, that have been deprived of their reputed _Substantial Forms_: Wherehe alledges the _Redintegration of Saltpetre_, successfully performed byhimself; though his Attempts, made upon the dissipation and re-union of_Amber_, _Allum_, _Sea-Salt_, and _Vitriol_, proved (by reason of_accidental_ hindrances rather, than of any impossibility in the Nature ofthe Thing) less successful. In the _Second_ and _Historical_ Part, the Author, appealing to theTestimony of Nature, to verifie his Doctrine, sets down, _both_ some_Observations_, of what Nature does without being over-ruled by the powerand skill of man; and some _Experiments_, wherein Nature is guided, and asit were, mastered by Art. The _Observations_ are four. 1. The _First_ is taken from what happens in the _Hatching of_ {194} _anEgge_; out of the _White_ whereof, which is a substance Similar, insipid, soft, diaphanous, colourless, and readily dissoluble in cold water, thereis by the _New_ and _Various_ contrivement of its small parts, caused bythe Incubation of the Hen, an Animal produced, some of whose parts areopacous, some red, some yellow, some white, some fluid, some consistent, some solid and frangible, others tough and flexible, some well, someill-tasted, some with springs, some without springs, &c. 2. The _Second_ is fetcht from _Water_, which being fluid, tastless, inodorous, diaphanous, colourless, volatile, &c. May by a _DifferingTexture_ of its parts, be brought to constitute Bodies, having qualitiesvery distant from these, as _Vegetables_, that have firmeness, opacity, odors, tasts, colours, Medicinal vertues; yielding also a true _Oyle_, thatrefuses to mingle with _Water_, &c. 3. The _Third_, from _Inoculation_; wherein, a small _Bud_ is able totransmute all the sap, that arrives at it, as to make it constitute a Fruitquite otherwise qualified, then that, which is the _genuine_ production ofthe Tree, so that the same sap, that in one part of the Branch constitutes(for Instance) a _Cluster of Haws_, in another part of the same Branch, maymake a _Pear_. Where the Author mentions divers other very considerableEffects of Inoculations, and inserts several Histories, all countenancinghis doctrine. 4. The _Fourth_, from _Putrified Cheese_; wherein, the _rotten_ part, bythe alteration of its Texture, will differ from the _Sound_, in colour, odor, taste, consistence, vermination, &c. The Experiments are ten. 1. _A Solution of Vitriol and Camphire_; in which by a change of Texture, appear'd the Production of a deep colour from a {195} white Body, and aclear Liquor without any external heat: The destruction of this Colour, byadding only some fair water: The change of an Odorous Body, _as Camphire_, into an Inodorous, by mixing it with a Body, that has scarce any sensibleodour of its own: The sudden restauration of the _Camphire_ to its nativescent and other qualities, by common water, &c. 2. _Sublimate, distill'd from Copper and Silver_, which both did whollyloose their Metalline forms, and were melted into brittle lumps, withcolours quite differing from their own; both apt to imbibe the moisture ofthe Air, &c. 3. _A solution of silver into Luna Cornea_: Whereby the opacous, malleableand hardly fusible Body of _Silver_, was, by the addition of a littlespirit of salt, reduced into Chrystals, differing from those of otherMettals; diaphanous also, and brittle, and far more easily fusible, thanSilver; wholly unlike either a Salt or a Mettal, but very like to a pieceof _Horn_, and withall insipid, though the Solution of Silver, be verybitter, and the spirit of salt, highly sowre, &c. 4. _An Anomalous Salt_; (which the Author had not, it seems the liberty toteach the Preparation off) whose Ingredients were purely Saline, and yetthe Compound, made up only of salt, sowre, and strongly tasted Bodies, wasrather _really_ sweet, than of any other taste, and when a little urgedwith heat, its odour became stronger, and more insupportable than that of_Aqua fortis_, _distilled Urine_ and even _spirit of salt Ammoniack_; butyet when these Fumes settled again into salt, their odour would again proveinoffensive, if not pleasant &c. 5. _A Sea-salt, whence Aqua fortis had been distilled_: Where the Liquor, that came over, proved an _Aqua Regis_: the substance in the bottom, hadnot onely a mild taste, and {196} affected the Pallat much more likesalt-peter, than Common salt; but was also very fusible, and inflammable, though produced of two un-inflammable bodies: and the same substance, consisting of _Acid_ salts, by a certain way of the Author, produced a_Fixt_ salt. 6. _Oyle of Vitriol poured upon a Solution of Bay-salt:_ whence wasabstracted a liquor, that by the smell and Taste appeared to be a spirit ofsalt. In which operation, the mixture, by working a great change ofTexture, did so alter the nature of the compounding Bodies, that thesea-salt, though a considerably fixt Body, was distill'd over in a moderateFire of sand, whilst the Oyl of Vitriol, though no such gross salt, was bythe same operation so fixt, as to stay behind: Besides that the same, by acompetent heat yeilded a substance, though not insipid, yet not at all ofthe taste of Sea-salt, or of any other pungent one, much less having thehighly corrosive acidity of oyl of Vitriol, &c. 7. _A dissolvent, made by pouring a strong spirit of Nitre on the rectifiedOyl of the Butter of Antimony, and then distilling off all the liquor, thatwould come over, &c. _ This _Menstruum_ (called by the Author _Peracutum_)being put to highly refined Gold, destroyed its Texture, and produced, after the method prescribed in the book, a _true Silver_, as its whitenessin colour, dissolublenes in _Aqua fortis_, and odious Bitterness, didmanifest: which change of a Mettal, commonly esteemed to be absolutelyindestructible by Art, though it be far from being _Lucriferous_, is yetexceedingly _Instructive_; as is also the way, the Author here adds, of_Volatilizing_ Gold, by the power of the same _Dissolvent_. 8. _Aqua fortis, concoagulated with differing Bodies_, produced verydiffering Concretes: And the same Numeral Saline Corpuscles, that beingassociated with those of one Mettal, had already produced a Body eminent inone Taste, did {197} afterwards, being freed from that Body, compose aLiquor of a very differing taste; and after _that_ too, being combin'd withthe parties of another Mettal, did with them constitute a Body of a veryeminent Taste, as opposite as any one can be to both the other Tasts; andyet these Saline Corpuscles, being instead of this second Mettal, associated with such a one as that, they are driven from, did therewithexhibite again the first of the three mention'd Tasts. 9. _Water transmuted into Earth_, though the Author saith of thisTransmutation, that it was not so perfect, as he wish'd, and as he hopes tomake it. 10. _A mixture of Oyle of Vitriol and Spirit of Wine. _ These two Liquors, being of odd Textures in reference to each other, their conjunction anddistillation made them exhibite these _Phænomena_: _vid. _ That, whereasSpirit of Wine has no great, nor good scent, and moderately dephlegm'd Oylof Vitriol is wont to be inodorous; the Spirit, that first came over fromtheir mixture, had a scent not only very differing from Spirit of Wine, butfrom all things else, that the Author ever smelt; the Odor being veryfragrant & pleasant, and so subtle, that in spight of the care taken inluting the Glasses exactly together, it would perfume the neighbouringparts of the _Laboratory_, and afterwards smell strongly at some distancefrom the Viol, wherein it was put, though stopt with a close Cork coveredwith two or three several Bladders. But, after this volatile andodoriferous Spirit was come over, and had been follow'd by an Acid Spirit, it was at last succeeded by a strongly stinking Liquor, &c. But _Manum de Tabula_: the Book it self will certainly give a satisfactionfar beyond what here can be said of it. {198} * * * * * _Some New observations about the Planet _Mars_, communicated since thePrinting of the former sheets. _ There was very lately produced a Paper, containing some observations, madeby Mr. _Hook_, about the Planet _Mars_; in the _Face_ whereof he affirmedto have discovered, in the late months of _February_ and _March_, thatthere are several _Maculæ_ or _Spotted parts_, changing their place, andnot returning to the same Position, till the next ensuing night near aboutthe same time. Whence it may be collected, that _Mars_ (as well as_Jupiter_, and the _Earth_, &c. ) does move about his own _Axis_, of which afuller account will be given hereafter, God permitting. This short andhasty intimation of it, is intended onely to invite others, that haveopportunity, timely to make Observations, (either to confirm, or rectify)before _Mars_ gets out of sight. * * * * * Printed with Licence for _John Martyn_, and _James Allestry_, Printers tothe Royal Society. 1666. {199} * * * * * _Num. _ 12. PHILOSOPHICAL_TRANSACTIONS. _ * * * * * _Munday_, _May_ 7. 1666. * * * * * The Contents. _A way of Preserving Birds taken out of the Egge, and other small _Fetus's_; communicated by _Mr. Boyle_. An Extract of a Letter, lately sent to _Sr. Robert Moray_ out of _Virginia_, concerning an unusuall way of Propagating Mulberry-trees there, for the better improvement of the _Silk-Work_; together with some other particulars, tending to the good of that _Royall_ Plantation. A Method, by which a Glass of a small Plano-Convex Sphere may be made to refract the Rayes of Light to a _Focus_ of a far greater distance, than is usuall. Observations about _Shining Worms_ in Oysters. Observations of the Effects of _Touch_ and _Friction_. Some particulars, communicated from forrain Parts, concerning the Permanent _Spott_ in _Jupiter_; and a contest between two Artists about _Optick-Glasses_, &c. An Account of a Book written by _Dr. Thomas Sydenham_, entituled, _Methodus Curandi Febres, propriis Observationibus superstructa_. _ * * * * * _A way of preserving Birds taken out of the Egge, and other small_Fætus's_; communicated by _Mr. Boyle_. _ This was imparted in a Letter, as follows; [Sidenote: * _In the Usefulness of Experimental Philosophy. _] The time of the year invites me to intimate to you, that among the otherUses of the Experiment, I long since presented the _Society_, of preservingWhelps taken out of the Dams womb, and other _Fætus's_, or parts of them, in _Spirit of Wine_; I {200} remember, I did, when I was sollicitous toobserve the Processe of Nature in the Formation of a Chick, open Hens Eggs, some at such a day, and some at other daies after the beginning of theIncubation, and carefully taking out the _Embryo's_, embalmed each of themin a distinct Glass (which is to be carefully stopt) in _Spirit of Wine_:Which I did, that so I might have them in readinesse, to make on them, atany time, the Observations, I thought them capable of affording; and to letmy Friends at other seasons of the year, see, _both_ the differingappearances of the Chick at the third, fourth, seventh, fourteenth, orother daies, after the Eggs had been sate on, _and_ (especially) someparticulars not obvious in Chickens, that go about; as the hanging of theGutts out of the _Abdomen_, &c. How long the tender _Embryo_ of the Chicksoon after the _Punctum saliens_ is discoverable, _and_ whilst the Bodyseems but a little Organized Gelly, _and_ some while after _That_, will bethis way preserv'd, without being too much shrivel'd up, I was hindred bysome mischances to satisfie my self: but when the _Fætus's_, I took out, were so perfectly formed as they were wont to be about the seventh day, andafter, they so well retain'd their shape and bulk, as to make me not repentof my curiosity: And some of those, which I did very early this Spring, Ican yet shew you. I know I have mention'd to you an easie application ofwhat I, some year since, made publick enough; but not finding it to havebeen yet made by any other, and being perswaded by Experience, that it maybe extended to other _Fætus's_, which this season (the _Spring_) is time tomake provision off, I think the _Advertisement_ will not seem unseasonableto some of our Friends; though being now in haste, and having in mythoughts divers particulars, relating to this way of Preserving Birds takenout of the Egge, and other small _Fætus's_, I must content my self to havemention'd that, which is _Essential_, leaving divers other things, which alittle practise may teach the Curious, unmention'd. Notwithstanding which, I must not omit these two Circumstances; the _one_, that when the Chick wasgrown big, before I took it out of the Egge, I have (but not constantly){201} mingled with the _Spirit of Wine_, a little Spirit of _SalArmoniack_, made (as I have elsewhere delivered) * by the help of_Quick-lime_: which Spirit I choose, because, though it abounds in a Saltnot Sowre, but Urinous, yet I never observed it (how strong soever I madeit) to coagulate Spirit of Wine. The _other_ circumstance is, that Iusually found it convenient, to let the little _Animals_, I meant toimbalme, lie for a little while in ordinary Spirit of Wine, to wash off thelooser filth, that is wont to adhere to the Chick, when taken out of theEgge; and then, having put either the same kind of Spirit, or better uponthe same Bird, I suffer'd it to soak some hours (perhaps some daies, _prore nata_) therein, that the Liquor, having drawn as it were what Tinctureit could, the _Fætus_ being remov'd into more pure and well dephlegm'dSpirit of Wine, might not discolour it, but leave it almost as limpid, asbefore it was put in. * * * * * _An Extract of a Letter, sent lately to Sir _Robert Moray_ out of_Virginia_, concerning an _unusual_ way of propagating _Mulberry trees_there, for the better improvement of the _Silk-Work_; together with someother particulars, tending to the good of that _Plantation_. _ I am disappointed at this time of some Rarities of Minerals, Mettals, andStones; but you may have them any other time, as conveniently, &c. I haveplanted here already ten thousand _Mulberry trees_; and hope, within two orthree years, to reap good silk of them. I have planted them in a wayunusual here, which advances them two or three years growth, in respect oftheir being sown in seed: And they are now, at writing hereof all holdinggood, although this has been a very long and bitter winter with us, muchlonger and colder, than ever I did find it in _Scotland_ or _England_. Iintend likewise to plant {202} them all, as if they were _Currants_ or_Goos-berries_, so thick as hedges; whereby one man may gather as many ofthem, as otherwise, when they are planted in trees at distance, fourpersons my do. Expedient is the benefit of this Trade. Having discoursed ofthis new way to all here; they are generally inclinable to it; consideringthat the Planting their Trees, as before, at distance, and letting themgrow high, has been the main obstruction of that work hitherto, and theloss of their time and gain: but being in hedges, they will be always youngtender plants; and consequently will be easily cut in great quantities witha pair of Garden Sizzers. But there may be suggested yet another, andperhaps a better way; which is, to sowe some Acres with _Mulberry seed_, and to cut it with a sith, and ever to keep it under. I have also bethoughtmy self of a new way, for a few hands to serve many Worms, and that morecleanly than before: which also will be a means, without more trouble orpains, to separate unhealthy worms from healthful; and by which a greatmany more may be kept in a room, than otherwise upon shelves, as is usualhere. Besides this, I have sown a little _French Barley_ and _Rice seed_, and am thinking on a way of un-husking them with expedition, and sopreparing them for the Merchant, as they use to be: But if you can informme, how they are prepared, you may save me some labour. If I had any_Coffee_ in husks, or any other vegetable commodity, from the Streights totry, I would here make tryal with them. Its like, that some of thoseMerchants that are of your _Society_, and keep a Correspondency there, mayassist in procuring them. By the latter ships I intend to send you a Newsort of sweet sented _Tobacco_, which I have not yet had time to improve. * * * * * _A Method, by which a Glass of a small Plano-convex Sphere may be made torefract the Rayes of light to a _Focus_ of a far greater distance, than isusual. _ This is proposed by Mr. _Hook_, in consequence of what was {203} mention'dfrom him in _Numb. _ 4 _pag. _ 67, of these _Transactions_. Prepare (_saith he_) two Glasses, the one exactly flat on both sides, theother flat on the one side, and convex on the other, of what Sphere youplease. Let the flat Glass be a little broader than the other. Then letthere be made a Cell or Ring of Brass, very exactly turn'd, into whichthese two Glasses may be so fastened with Cement, that the plain surfacesof them may lye exactly paralell, and that the Convex-side of thePlano-convex-Glass may lye inward; but so, as not to touch the flat of theother Glass. These being cemented into the Ring very closely about theedges, by a small hole in the side of the Brass-ring or Cell, fill theinterposed space between these two with _Water_, _Oyl of Turpentine_, _Spirit of Wine_, _Saline Liquors_, _&c;_ then stop the hole with a screw:and according to the differing refraction of the interposed Liquors, soshall the _Focus_ of the compound Glass be longer or shorter. But this (adds the _Proposer_) I would only have look't upon, as oneinstance of many (for there may be others) of the _Possibility_ of making aGlass, ground in a smaller Sphere, to constitute a Telescope of a muchgreater length: Though (not to raise too great exspectation) I must add, That of _Spherical_ object glasses, those are the best, which are made ofthe greatest Sphere, and whose substance hath the greatest refraction. * * * * * _Observations about _Shining Worms_ in Oysters. _ These Observations occur in the _French journal_ of _April_ 12. 1666. Intwo letters, written by M. _Auzout_ to M. _Dela Voye_; whereof thesubstance may be reduced to the following particulars. 1. That M. _Dela Voye_ having observed, as he thought, {204} some shiningWorms in Oysters; M. _Auzout_, being made acquainted with it, did firstconceive, they were not Worms (unless they were crushed ones) that shin'd, as having not been able then to discern any parts of a Worm; but only someshining clammy moysture; which appeared indeed like a little Star of ablewish colour, and stuck to the Oyster-shell; being drawn out, shone inthe Air its whole length (which was about four or five lines, ) and when putupon the _Observers_ hand, continued to shine there for some time. 2. That M. _Auzout_ afterwards, causing more than 20. Douzen of Oysters tobe open'd at Candle-light, really saw, in the dark, such shining worms inthem; and those of three sorts. _One_ sort was whitish, having 24. Or 25. Feet on each side, forked; a black speck on one side of the head (taken byhim for a _Chrystallin_) & the back like an Eele, stript off her skin. The_second_, red, and resembling the common _Glow-worms_, found at Land, withfolds upon their backs, and feet like the former; and with a nose like thatof a dog, and one eye in the head. The _third_ sort was speckled, having ahead like that of a Sole, with many tufts of whitish hair on the sides ofit, 3. That, besides these, the _Observer_ saw some much bigger, that weregrayish, with a big head, and two horns on it, like those of a Snayl, andwith 7. Or 8. Whitish feet, but these, though kept by him in the night, shin'd not. 4. That the two first sorts are made of a matter easily resoluble, theleast shaking or touch turning them in into a viscous and aqueous matter;which falling from the shell, stuck to the _Observers_ fingers, and shonethere for the space of 20. Seconds: and if any little part of this matter, by strongly shaking the shell, did fall to the ground, it appear'd like alittle piece of a flaming Brimstone; and when shaken off nimbly, it becamelike a small shining Line, which was dissipated before it came to theground. {205} 5. That this shining matter was of different colour; some, whitish, some, reddish; but yet that they afforded both, a light which appear'd aviolet to his eye. 6. That it is very hard to examine these worms entire (especially the whiteones) because that at the least touch they doe burst, and resolve into aglutinous moysture; whence also if it were not for their feet, that arediscover'd in their matter, none would judge them to be Worms. 7. That among those, which he observed, he saw two more firm, than therest, which shone all over; and when they fell from the Oyster, twinkledlike a great star, shining strongly, and emitting rays of a violet-light byturns, for the space, (as touch't above) of 20. Seconds. WhichScintillation the _Observer_ imputes to this, that those worms being alive, and sometimes raising their head, sometimes their tayle, like a Carpe, thelight increased and lessened accordingly; seeing that, when they shone not, he did, viewing them by a Candle, find them dead. 8. That forcibly shaking the Oyster-shells in the dark, he sometimes sawthe whole shell full of lights, now and then as big as a fingers end; andabundance of this clammy matter, both red and white, (which he judges tohave been Worms) burst in their holes. 9. That in the shaking he saw all the Communications of these littleVerminulous holes, like to the hole of Worms in Wood. 10. That in more than 20 douzen of Oysters he shook no shell (10. Or 12. Excepted) but it emitted light: And found some of this light in sixteen ofthe Oysters themselves. 11. That this light occurs more frequently in big, than small Oysters; inthose that are pierced by the Worm, oftner, than {206} in those that arenot, and rather upon the Convex-side, than the other; and more in freshones; than in the stale. 12. That having somewhat scaled the Convex-side of the shell, anddiscover'd the Communication of the holes, wherein the often-mention'dviscous moysture, that has any form of insects, is found; he smelt a scent, that was like the water of a squeesed Oyster. 13. That the Worms give no light, when irritated, but if they do, the lightlasts but a very little time, whereas that which appears in those, thatwere not angred before, continues a great while; the _Observer_ affirmingto have kept of it above 2 hours. So far the _Journal des Scavans_; which intimates withal, that if the_Observers_ had had better _Microscopes_, they could have better examin'dthis matter. But since the curious here in _England_ are so well furnish with good ones, 'tis hoped, that they will employ some of them for further and more minuteObservations of these Worms; it being a matter, which, joyned with otherObservations, already made by some excellent persons here, (especially Mr. _Boyle_) upon this subject of Light, may prove very luciferous to thedoctrine of it, so much yet in the dark. * * * * * _Some Observations of the Effects of _Touch_ and _Friction_. _ The Operations and Effects of _Touch_ and _Friction_ having been latelymuch taken notice off, and being lookt upon by some, as a great _Medical_Branch, for the curing of many diseases and infirmities; it will perhapsnot be unseasonable to mention (here also) some Observations relatingthereunto; which may give an occasion to others, to consider this subjectmore, than has been done heretofore, and to make {207} further Observationsand Tryals concerning the power of the same. And _First_, the Illustrious Lord of _Verulam_, in his _History of Life andDeath_, Histor. 6. §. 3. Observes, That _Motion_ and _Warmth_ (of whichtwo, _Friction_ consists) draws forth, into the parts, New Juyce andVigour. And _Canon. _ XIII. He affirms, That _Frictions_ conduce much to_Longevity_. See the same, _Connex. _ ix. §. 26. &c. _Secondly_, The Honourable _Robert Boyle_, in his _Usefulness ofExperimental Philosophy_, _sect_ 2. _ch. _ 15. Considering the Body of aLiving man or any Animal, as an Engine, so composed, that there is aconspiring communication betwixt its parts, by vertue whereof a very slightimpression of adventitious matter upon some one part, may be able to work, on some other distant part, or perhaps on the whole Engine, a change farexceeding, what the same adventitious matter could do upon a Body not socontrived: Representing, I say, an Animal in this manner, and thenceinferring, how it may be alter'd for the better or worse by motions orimpulses, confessedly _Mechanicall_, observes, How some are recover'd fromswouning fits by pricking; others grow faint and do vomit by the baremotion of a Coach; others fall into a troublesome sickness by the agitationof a Ship, and by the Sea-air (whence they recover by rest, and by going ashore. ) Again, how in our Stables a Horse well-curried is half-fed: Howsome can tell by the Milk of their Asses, whether that day they have beenwell curried or not: Arguing hence, that if in _Milk_ the alteration is soconsiderable, it should be so likewise in the _Blood_, or other Juyces, ofwhich the Blood is elaborated, and consequently in divers of the principalparts of the Body. Where also (upon the authority of _Piso_) he refers theReader to the _Brasilian_ Empiricks, whose {208} wild _Frictions_, asunskilfully as they order them, do strange things, both in _preservinghealth_, and _curing diseases_; curing Cold and _Chronical_ ones by_Friction_, as they do _Acute_ ones, by _Unction_. _Thirdly_, The learned Dr. _John Beale_, did not long since communicate bysome Letters; _First_, that he could make good proof of the curing orkilling a very great and dangerous _Wen_ (that had been very troublesomefor two or three years, ) by the application of a dead mans hand, whence thePatient felt such a cold stream pass to the Heart, that it did almost causein him a fit of swouning. _Secondly_, that, upon his brothers knowledge, acertain Cook in a Noble Family of _England_ (wherein that brother of histhen lived) having been reproached for the ugliness of his _Warty_ hands, and return'd for answer, that he had tried many remedies, but found none, was bid by his Lord, to rub his hand with that of a dead man; and that thisLord dying soon after, the Cook made use both of his Lords advise and hand, and speedily found good effect. (Which is also confirm'd by what Mr. _Boyle_ relates in his lately mentioned _Book_, of Dr. _Harvey's_frequently succesfull triall, of curing some Tumors or Excrescencies, byholding on them such a Hand. ) Here is _Friction_ or _Touch_, to mortifieWens, to drive away swellings and Excrescencies: And why not to repell ordissipate Spirits, that may have a dangerous influence upon the Brain, orother parts; as well as to call forth the retired ones into the habit ofthe Body, for Invigoration? _Thirdly_, that a Gentleman, who came latelyout of _Ireland_, lay at his House, and inform'd him of an aged Knightthere, who having great pain in his feet, insomuch that he was unable touse them, suffered, as he was going to bed, a loving _Spaniell_ to lick hisfeet; which was for the present very pleasing to him, so that he used itmornings and evenings, till he found the pain appeased, and the use of hisfeet restored. This, saith {209} the _Relater_, was a gentle touch, andtranspiration; for he found the Spirits transpire with a pleasing Kind ofTitillation. _Fourthly_, that he can assure of an honest Blacksmith, who byhis healing hand converted his Barrs of Iron into Plates of Silver; and hadthis particular faculty, that he caused Vomitings by stroaking the Stomack;gave the Stool by stroaking the Belly; appeased the Gout, and other paines, by stroaking the parts affected. * * * * * _Some particulars, communicated from forraign parts, concerning thePermanent _Spott_ in _Jupiter_; and a Contest between two Artists about_Optick Glasses_, &c. _ [Sidenote: _See _Numb. 1_. Of these _Transactions_; by the date whereof itwill appeare, that that _Spot_ was observed in _England_, a good whilebefore any such thing was so much as heard of. _] _Eustachio de Divinis_ (saith the _Informer_, ) has written a large Letter, wherein he pretends, that the Permanent Spot in _Jupiter_ hath been firstof all discovered with _his_ Glasses; and that the P. _Gotignies_ is thefirst that hath thence deduced the Motion of _Jupiter_ about his _Axis_;and that Signior _Cassini_ opposed it at first; to whom the said_Gotignies_ wrote a letter of complaint thereupon. The same _Eustachio_ pretends likewise, that his great Glasses excell thoseof _Campani_; and that in all the tryals, made with them, they haveperformed better; and that _Campani_ was not willing to do, what wasnecessary for well comparing the one with the other. _viz. _ To put equall_Eye-glasses_ in them, or to exchange the same Glasses. The said _Divini_ affirms also, that he hath found a way to {210} know, whether an Object glass be good or not, onely by looking upon it, withouttrying. This would be of good use, especially if it should extend so far asto discerne the goodness of such a glass, whilst it is yet on the Cement. * * * * * _An Account of Dr. _Sydenham's_ Book, entituled, _Methodus Curandi Febres, Propriis observationibus superstructa_. _ This _Book_ undertakes to deliver a more certain and more genuine Method ofcuring Feavers and Agues, than has obtained hitherto: And it beingpremised, _First_, that a Fever is Natures Engine, she brings into thefield, to remove her enemy; or her handmaid, either for evacuating theimpurities of the blood, or for reducing it into a New State: _Secondly_, that the true and genuine cure of this sickness consists in such atempering of the Commotion of the Blood, that it may neither exceed, nor betoo languide: This, I say, being premised by the Author, he informs theReader; In the _First Section_, of the different Method, to be employed in the cureof Feavers, not only in respect of the differing constitutions and ages ofthe patients, but also in regard of the differing seasons of one and thesame year, and of the difference of one year from another. As to the_Former_, he shews, in what sorts of _Patients_, and at what time of theFeaver, Phlebotomy, or Vomiting, or both, are to be used; and when andwhere not: In what space of time the _Depuration_ if nature be notdisturbed or hindred in her work, will be perform'd: When _Purgatives_ areto be administred: How that _Diarrhea's_ happen, if the _Patient_ had inthe {211} beginning of the Feaver an inclination to vomit, but no vomit wasgiven; and that those symptoms, which commonly are imputed to a malignity, do, for the most part, proceed from the Relaxation of the tone of theBloud, caused by Medicines too refrigerating, or by the unseasonable use ofGlisters in the declination of the disease. As to the _Latter_, heobserves, that one of the chief causes, rendring the Cure of Feavers souncertain and unsuccessfull, is, that _Practitioners_ do accommodate theirobservations, they take from the successful cure of some Feavers in oneseason or the year, or in some one year, to that of all Feavers in anyseason, or in any year whatsoever. And here he observes, _first_, howvigorous the blood is in the _Spring_, and how dispirited in _Autumn_; andthence regulates the letting of bloud, and Vomiting, and the giving ofGlisters. _Next_, how difficult it is, to assign the cause of thedifference between the Feavers of _Several years_; and to prognosticate ofthe salubrity or insalubrity of the following part of the year: where yethe insinuates, that, when _Insects_ do swarm extraordinarily, and whenFeavers and Agues (especially _Quartans_) appear very early, as about_Midsummer_, then _Autumn_ commonly proves very sickly. _Lastly_, whatmethod and Cautions are to be used in the Cure of _Epidemical_ Feavers. In the _Second Section_, he treats of the _Symptoms_, accompanying_Continued_ Feavers; as _Phrensies_, _Pleurisies_, _Coughs_, _Hicoughs_, _Fluxes_, &c. Shewing, both whence they are caused, and how they are to becured: Where having inserted a considerable _Paragraph_, touching a certain_Symptomatical_ Feaver in the _Spring_, to be cured like Plurisies; hementions among many Observables, this, as a chief one, that _Laudanum_, orany other _Narcotick_ given against the _Phrensy_, in the beginning, progress, or height of a Feaver, does rather hurt, than good, but in thedeclination thereof, is used with good success. To all which he subjoins aparticular {212} accompt of the _Iliac Passion_ (esteem'd by him to besometimes a _Symptome_ also of Feavers;) not only discoursing of its cause(a preposterous inversion of the Intestins, proceeding either fromObstruction, or Irritation, ) but adding also a very plain way of Curing thesame; and that not by the use of _Quick-silver_ or _Bullets_ (by him judgedto be frequently noxious) but only by _Mint-water_; and the application ofa Whelp to the Patients stomach; to strengthen the same, and to reduce itagain to its natural motion. In the _Third Section_, he treats of _Intermittent_ Feavers, or of _Agues_:Where he discourses of the times of the _Cold_ and _Hot_ fits, and of_that_ of the _Separation_ of the subdued aguish matter: Finds difficultyin giving a satisfactory accompt of the _return of Fits_: distinguishesAgues into _Vernal_ and _Autumnal_: Takes notice, that as there are few_Continued_ Feavers, so generally there are only _Quotidians_ and_Tertians_, in the _Spring_; and only _Tertians_ and _Quartans_ in_Autumn_; Of which having offered Reasons, that seem considerable, heproceeds to his Method of curing them; and, laying much weight upon thesaid difference, he prescribes and urges different ways to be used in thatcure: Interserting among other things these notes; _First_, that the Periodof Fermentation in Feavers, both _Continued_ and _Intermittent_, is (ifleft to Natures own conduct, and well regulated, if need be, by Art)perform'd in about 336. Hours or 14 dayes, subducting in _Intermittent_ones, the hours of intermission, and counting 5½ hours for every Paroxism;and imputing the excursion beyond that time to the disturbance given tonature by the error of Practitioners. _Secondly_, that whoever hath had a_Quartan_ formerly, though many years be pass'd, shall, if he chance tohave another, be _soon_ freed from it; and that a Physician knowing _that_, may confidently predict _this_. {213} In the _Fourth Section_, the Author, in conformity to the Custom of thosethat write of Feavers, discourses of the _Small-pox_; and _First_, examining the cause of this sickness and its universality, delivers hispeculiar opinion of the bloud's endeavouring a Renovation or a New Texture(once at least in a Mans life) and is inclin'd to preferr the same to thereceived doctrine of its malignity. _Then_, having laid down, for afoundation of the Cure, the two times, of _Separation_ and _Expulsion_, heargues as well against too high an Ebullition or too hasty a separation (bya hot diet or high Cordials) as against too languid a one (by Blooding, Purges, and Cooling medicines. ) The like he does to the Time of_Expulsion_, forbidding _both_ immoderate Heat (whereby Nature's expellingoperation is disturbed by a precipitated and too thick a crowd of theprotruded pustuls, ) _and_ too much Cooling, whereby due Expulsion ishindred. In short, he advises, to permit Nature to do her own work, requiring nothing of the Physician, but to regulate her, when she isexorbitant, and to fortifie her, when she is too weak. He concludes all, with delivering a Model of the Method, he would use for his own only Son, if he should fall into this Sickness. * * * * * Advertisement. _Whereas 'tis taken notice of, that several persons perswade themselves, that these_ Philosophical Transactions _are publish't by the_ RoyalSociety, _notwithstanding many circumstances, to be met with in the alreadypublish't ones, {214} that import the contrary; The Writer thereof haththought fit, expresly here to declare, that that perswasion, if there beany such indeed, is a meer mistake; and that he, upon his_ Private _account(as a Well-wisher to the advancement of usefull knowledge, and a Furthererthereof by such Communications, as he is capable to furnish by thatPhilosophical Correspondency, which he entertains, and hopes to enlarge)hath begun and continues both the composure and publication thereof: Thoughhe denies not, but that, having the honour and advantage of being a_ Fellow_of the said_ Society, _he inserts at times some of the Particulars thatare presented to them; to wit, such as he knows he may mention withoutoffending them, or transgressing their Orders; tending only to administeroccasion to others also, to consider and carry them further, or to Observeor Experiment the like, according as the nature of such things mayrequire. _ * * * * * Printed with Licence for _John Martyn_, and _James Allestry_, Printers tothe Royal Society. 1666. {215} * * * * * _Numb. _ 13. PHILOSOPHICAL_TRANSACTIONS. _ * * * * * _Munday_, _June_ 4. 1666. * * * * * The Contents. _Certain _Problems_ touching some Points of Navigation: Of a new Contrivance of _Wheel-Barometer_, much easier to be prepar'd, than others. An account of _Four Suns_ which lately appear'd in _France_; and of two, unusually posited, _Rainbows_, seen in the same Kingdom. A Relation of an Accident, by Thunder and Lightning, in _Oxford_. An Experiment, to examine, what _Figure_ or Celerity of Motion begetteth or increaseth _Light_ and _Flame_. Some Considerations touching a Letter in the _Journal des Scavans_ of _May__ 24. 1666. * * * * * _Certain _Problems_ touching some Points of _Navigation_. _ These _Problems_ are presented by the Learned and Industrious _NicolausMercator_, for the advancing of that Excellent and Beneficial Science, _Navigation_, as follows: The line of _Artificial Tangents_, or the _Logarithmical Tangent-line_, beginning at 45 deg. And taking every half _degree_ for a whole one, isfound to agree pretty near with the _Meridian-line_ of the _Sea-Charte_;they both growing, as it were, after the same Proportion. But the Table of_Meridional_ degrees being calculated only to every _Sexagesimal_ minute ofa degree, shews some small difference from the said _LogarithmicalTangent-line_. Hence it may be doubted, whether that difference do notarise from that little errour, which is committed by calculating the Tableof _Meridional_ degrees _only_ to every minute. {216} Mr. _Oughtred_ in the VI. _Chap. _ of his _Navigation_, annexed to the Book, entituled, _The Circles of Proportion, and the Horizontal Instrument_ &c. Mentions an Artifice, by himself discover'd, by which it may be effected, that the small Parts of the _Meridian_ be not _one_ minute (which on theface of the _Earth_ answers to above an _English_ Mile) but thehundred-thousanth, or, if need be, the millioneth part of a minute, scarceexceeding one fifteenth part of an Inch: Which thing, _he saith_, he isable to perform in _Tables_ unto the _Radius_ 10000000; yet nothing at alldiffering either in their form or manner of working from those that are nowcommonly in use. But which way this is to be done, this _Author_ hath not made known to thePublick. And, though such _Tables_ unto the _Radius_ 10000000, had beenbrought to light, yet would they not be sufficient to prove the identity orsameness of the said two Lines, as to continue the comparison between themas far, as the one of them, _videl. _ the _Logarithmicall Tangent-line_, isalready calculated, that is; to Ten places, besides the _Charactoristick_. Now therefore, if a certain Rule could be produced, by which the Agreementor Disagreement of the said two Lines might be shew'd, not only to thatExtent of places, to which that _Tangent Line_ is already calculated, butalso to as many more, as the same may be yet further extended unto, in_infinitum usque_; surely that rule would not only save us the labour ofmaking _Tables_ unto the _Radius_ 10000000; but also the _Helix_ or SpiralLine of the Ships Course would be reduced to a more precise exactness, thanever was pretended by Him: and this most Noble and Useful Science (as Hejustly calls it) which is the Bond of most disjunct Countries, and theConsociation of Nations farthest remote, would attain its full lustre andperfection. Besides, that the same Rule would also discover a far easier way of making_Logarithmes_, than ever was practised or known; and therefore might serve, when ever there should be occasion, to extend the _Logarithmes_ beyond thatnumber of places, that is already extant. Moreover such a rule would enable men to draw the _Meridian_ line_geometrically_, that is, without _Tables_ or _Scales_: which indeed {217}might also be done, by setting of the _Secants_ of every whole or halfdegree, if there were not this Inconveniency in it (which is not in myRule:) That a Line composed of so many small parts, would be subject tomany errours, especially in a small compass. The same Rule also will serve, to find the Course and Distance between twoPlaces assigned, as far, as practice shall require it; and that, withoutany Table of _Meridional_ parts, and yet with as much ease and exactness. And seeing all these things do depend on the solution of this Question, _Whether the Artificial Tangent-line be the true Meridian-line?_ It istherefore, that I undertake, by God's assistance, to resolve the saidQuestion. And to let the world know the readiness and confidence, I have tomake good this undertaking, I am willing to lay a _Wager_ against any oneor more persons that have a mind to engage, for so much as _anotherInvention_ of mine (which is of less subtlety, but of far greater benefitto the publick) may be worth to the Inventor. For, the great advantage, that all Merchants, Mariners, and consequentlythe Common-wealth, may receive from this _other Invention_, is, in myjudgment, highly valuable; seeing it will oftentimes make a ship sail, though, according to the common way of sailing, the wind be quite contrary, and yet as near to the place intended, as if the wind had been favourable:Or, if you will, it will enable one to gain something in the intended way, whether the wind be good or no (except only when you go directly South orNorth) but the advantage will be most, where there is most need of it, thatis, when the Wind is contrary: So that one may very often gain a fifth, fourth, third part, or more of the intended voyage; according as it islonger or shorter, _viz. _ always more in a longer Voyage, where the gain ismore considerable, and more welcome; not only by saving Time, but alsoVictuals, Water, Fuel, Mens health, and so much Room in the ship. All this, which is here pretended, the Proposer is to make good by theVerdict of some able Men, who also may give a guess, what this latterInvention may be worth to the owner: And for so much, and no more, he willstand engaged against {218} any one or more Persons, that he will and shallresolve the _Question_ above-mention'd, _viz. Whether the ArtificialTangent-line be the true Meridian-line, yea or no?_ And if he do not, thatthen he will loose, and transport to the other Party the whole benefit ofthe last mentioned invention. But if, on the contrary, he do prove ordisprove the Identity of the said two lines, to the Judgment of some able_Mathematicians_, That then so much money be paid him by the other Party, as the said Invention was valued. And, whereas there are often Wagers laid about things that concern theEngagers little or nothing; 'tis thought, that it would concern allMerchants, Mariners, and all Lovers of the common good, rather to laywagers against one another about Things of this nature, where the Gainerdoth gain as well, as if he had laid his wager about something else, andthe Looser hath so far the benefit as well as the Gaine, That he seeththereby promoted the thing, that concerns them both alike. Now therefore, to the end, that the Looser may have his benefit by it, aswell as the Gainer, it would not be amiss, that the condition were madethus, that the latter should grant the moity of his gain to the Proposer;that thereby he might be enabled to bring to light both those, and someother useful inventions, for the Service of Mankind. And to manifest, thatit is not for his own interest only, that the _Proposer_ mentions this; heis willing to impart from that moity, so received, the full moity again toany other person within his Majesty's Dominions, who shall first of allgive notice of his Undertaking to prove or disprove the said Identity, andperform it accordingly within the space of two Months, to be computed fromthe present Date. Those that have a mind to engage, may repair to thePrinters of these _Tracts_, where they may know further. [Illustration] * * * * * _A new Contrivance of _Wheel-Barometer_, much more easy to be prepared, than that, which is described in the _Micrography_; imparted by the Authorof that Book. _ This is only an easy way of applying an _Index_ to any _Common Barascope_, whether the Glass be only a Single Cane, or have a round Bolthead at thetop. And by the means thereof, the {219} Variation of the Altitude of the_Mercurial_ Cylinder, which at most is hardly three Inches, may be made asdistinguishable, as if it were three Foot, or three Yards, or as much more, as is desired. The manner hereof is visible enough by _Figure_ I: where A B C representsthe Tube, which may be either Blunt, or with a Head, as A B C (by whichlatter shape, more room is allow'd for any remainder of Air, to expand thebetter. ) This is to be filled with Quick-silver, and inverted as commonly;but into a Vessel of Stagnant Mercury, made after the fashion of I K, thatis, having its sides about 3 or 4 inches high, and the Cavity of it equallybig both above and below; and if it can be (besides that part, which isfill'd by the end of the _Mercurial_ Tube, that stands in it) of equalcapacity with the hollow of the Cane about B: For then the Quicksilverrising as much in the hollow of I, as it descends at B, the difference ofthe height in the Receiver I, will be just half the usual difference, Andif the receiving Vessel I K have a bigger Cavity, the difference will beless, but if less, the difference will be greater: But, whether thedifference be hereby made bigger or less, 'tis no great matter, since bythe contrivance of the _Wheel_ and _Index_ (which is more fully describedin the _Preface_ to the _Micrography_) the least variation may be made assensible as is desired, by diminishing the bigness of the Cylinder E, andlengthening the _Index_ F G, according to the Proportion requisite. * * * * * _An Account of _Four Suns_, which very lately appear'd in _France_, and oftwo _Raine-bows_, unusually posited, seen in the same Kingdom, somewhatlonger agoe. _ These _Phænomena_ are thought worthy to be inserted here, for theSpeculation of the Curious in those Kingdoms; as they were publisht in theFrench _Journal des Scavans_, of May 10, 1666. _viz. _ The 9th of _April_ of this present year, about half an hour past nine, there appear'd three Circles in the Sky. _One_ of them was very great, alittle interrupted, and white every where, without {220} the mixture of anyother colour. It passed through the midst of the Sun's _Disk_, and wasparallel to the _Horizon_. Its _Diameter_ was above a hundred degrees, andits _Center_ not far from the _Zenith_. The _Second_ was much less and defective in some places, having the Coloursof a Rainbow, especially in that part, which was within the great Circle. It had the true Sun for its Center. The _Third_ was less, than the first, but greater than the second; it wasnot entire, but only an Arch or Portion of a Circle, whose Center was fardistant from that of the Sun, and whose circumference did, by its middle, join to that of the least Circle, intersecting the greatest Circle by itstwo extreams. In this Circle were discerned also the Colours of a Rainbow, but they were not so strong, as those of the _Second_. At the place, where the circumference of this _Third_ Circle did close withthat of the _Second_, there was a great brightness of Rainbow-Colours, mixttogether: And at the two extremities, where this _Second_ Circleintersected the _First_, appear'd two _Parhelia's_ or Mock-suns; whichshone very bright, but not so bright, nor were so well defined, as the trueSun. The False Sun, that was towards the _South_, was bigger, and far moreluminous, than that towards the _East_. Besides those two _Parhelia's_, which were on the two sides of the true Sun, in the intersection of the_First_ and _Third_ Circle, there was also upon the _First_ great Circle, a_third_ Mock-sun, situated to the _North_, which was less and less bright, than the two others. So that at the same time there were seen _Four_ Sunsin the Heavens. [Illustration] [Illustration] _Figure_ II. Will illustrate the Position of this _Phænomenon_. A. _The Zenith or the Point Vertical to the place of Observation. _ B. _The true Sun. _ S C H N. _The great Circle, altogether White, almost parallel to theHorizon, which pass'd through the true Sun's Diske, and upon which were thefalse Suns. _ D E B O. _A Rain-bow about the Sun, forming an entire Circle, butinterrupted in some places. _ H D N. _A portion of a Circle, that was Excentrick to the Sun, and greaterthan the Circle_ D E B O, _which touch'd_ D E B O, _and was confounded withit in the point_ D. {221} H N. _The two Mock-Suns, in the intersection ofthe Semicircle_ H D N, _and the Circle_ S C H N: _The midst of which twoFalse-Suns was white and very luminous; and their Extremities towards_ D I_were tinged with the Colours of a Rainbow. The False Sun, mark'd_ N, _ wasfainter than that, which is mark'd_ H. C. _The Mock-Sun, all white, and far less shining, than the two others. _ I. _A space very dark betwixt_ R. _and_ D. [Sidenote: * _Those _Five_ Suns, that appear'd the 29 _March_, A. 1629. At_Rome_, between 2 or 3 of the Clock, in the afternoon, were thus posited;that the two of them, which were in the intersection of two Circles, appear'd in that of a Circle, which passed through the Sun's Diske, withanother, that was _Concentrick_ to the Sun: as may be seen in _Figure III_. Borrow'd (for the easier comparing them together) out of _Des-Cartes_ his_Meteors_, cap. X. _] This Appearance is look't upon as one of the notablest, that can be seen, by reason of the _Excentricity_ of the Circle H D N, and because that the_Parhelia_ * were not in the Intersection of the Circle D E B O with thegreat Circle S C H N, but in that of the Semi-circle H D N. As for the two odd _Rainbows_; they appear'd at _Chartres_ the 10. Of_August_, 1665. About half an hour past six in the Evening; and did crossone another almost at right Angles, as may be seen by _Fig. _ IV. [Illustration] The Rainbow, which was opposite to the Sun, in the usual manner, was moredeeply colour'd, than that, which cross'd it; though even the Colours ofthe first _Iris_ were not so strong, as they are now and then seen at othertimes. The greatest height of the stronger Rainbow, was about 45. Degrees; thefeebler Rainbow lost one of its Legs, by growing fainter, about 20 degreesabove the stronger; and the Leg below appear'd continued to the _Horizon_. These Rainbows did not _Just_ decussate one another at right Angles; therewas some 6 or 7 degrees difference. The fainter, seem'd to be a Portion ofa great Circle; and the stronger was but a Portion of a small Circle, asusually. The Sun, at their appearance, was about 6 degrees high above the _Horizon_, and towards the 17 _Azimuth_ of the West, Northward. {222} The Observer, M. _Estienne_, notes, that, when he made this Observation, the River of _Chartres_, which runs very near from _South_ to _North_, wasbetwixt him and the Rainbow; and that he stood Level with this River, whence he was distant not above 150 paces: which he adds, that the Curiousmay the better judge of this Observation. * * * * * _A Relation of an Accident by Thunder and Lightning, at _Oxford_. _ This was imparted by Dr. _Wallis_ in a Letter, written at _Oxford_, May 12, 1666. To the _Publisher_, as follows: I should scarce have given you so soon the trouble of another Letter, wereit not for an Accident which hapn'd here _May_ 10. I had that afternoon, about 4 of the clock heard it thunder at some distance. About 5 of theclock the Thunder coming nearer to us; it began to rain, and soon after(the rain withal increasing) the Thunder grew very loud, and frequent, andwith long ratling Claps (though not altogether so great, as I have someother times heard:) and the Lightning with flashes very bright(notwithstanding the clear day-light) and very frequent, (when at thefastest, scarce a full minute between one flash and another; many times notso much, but a second flash before the Thunder of the former was heard:)The Thunder for the most part began to be heard about 8 or 10 secondminutes after the flash; as I observ'd for a great part of the time by myMinute-Watch: but once or twice I observ'd it to follow (in a manner)immediately upon it, as it were in the same moment; and the lightningextream red and fiery. I do not use to be much apprehensive of Thunder andLightning, but I was at this time (I know not well, why?) veryapprehensive, more than ordinary, of mischief to be done by it, for itseem'd to me to be very low and near us (which made me so particular, as toobserve the distance of the flash by the noise) and very frequent, andbright, so that, had it been by night as it was by day, it would have beenvery terrible. And, though I kept within doors, yet I sensibly discover'd astinking sulphureous smell in the Air. About 7 of the clock it ended, before which time I had news brought me of a Sad Accident upon the {223}water at _Medley_ about a Mile or somewhat more distant from hence. TwoSchollars of _Wadham_-Colledge, being alone in a Boat (without a Water-man)having newly thrust off from shore, at _Medley_, to come homewards, standing near the Head of the Boat, were presently with a stroke of Thunderor Lightning, both struck off out of the Boat into the Water, the one ofthem stark dead, in whom, though presently taken out of the Water (havingbeen by relation, scarce a minute in it) there was not discerned anyappearance of life, sense, or motion: the other was stuck fast in the Mud(with his Feet downwards, and his upper parts above water) like a post notable to help himself out; but, besides a present stonying or numness, hadno other hurt; but was for the present so disturb'd in his senses, as thathe knew not, how he came there out of the Boat, nor could remember eitherThunder or Lightning, that did effect it: and was very feeble and faintupon it; which (though presently put into a warm Bed) he had not thoroughlyrecover'd by the next Night; and whether since he have or no, I know not. Others in another Boat, about 10 or 20 yards from these (as by theirdescription I estimate) felt a disturbance and shaking in their Boat, andone of them had his Chair struck from under him, and thrown upon him; buthad no hurt. Those immediately made up to the others, and (some leapinginto the Water to them) presently drew them either into the Boat or onShore; yet none of them saw these two fall into the Water (not looking thatway) but heard one of them cry out for help presently upon the stroke, andsmelt a strange stinking smell in the Air; which, when I asked him, thattold it me, what kind of stink? he said, like such a smell, as is perceivedupon the stricking of Flints together. He that was dead (when by putting into a warm Bed, and rubbing, and puttingstrong waters into his Mouth, &c. No life could be brought into him) wasthe next morning brought to town; where, among the multitudes of others, who came to see, Dr. _Willis_, Dr. _Mellington_, Dr. _Lower_, and my self, with some others, went to view the Corps: where we found no wound at all inthe skin, the face and neck swart and black, but not more, than might beordinary, by the settling of the blood: On the right side of the neck was alittle blackish spot about an inch long, and {224} about a quarter of aninch broad at the broadest, and was, as if it had been sear'd with a hotiron; and, as I remember, one somewhat bigger on the left side of the neck, below the Ear. Streight down the breast, but towards the left side of it, was a large place about three quarters of a Foot in length, and about twoinches in breadth, in some places more, in some less, which was burnt andhard, like Leather burnt with the fire, of a deep blackish red Colour, notmuch unlike the scorch'd skin of a rosted Pig. And on the fore-part of theleft Shoulder such another spot about as big as a Shilling; but that in theneck was blacker and seem'd more sear'd. From the top of the rightshoulder, sloping downwards towards that place in his Breast, was a narrowLine of the like scorched skin; as if somewhat had come in there at theneck, and had run down to the breast, and there spread broader. The buttons of his _Doublet_ were most of them off; which, some thoughtmight have been torn off with the blast, getting in at the neck, and thenbursting its way out: for which the greatest presumption was (to me) that, besides 4 or 5 buttons wanting towards the bottom of the Breast, there wereabout half a dozen together clear off from the bottom of the collardownwards, and I do not remember, that the rest of the buttons seem to benear worn out, but almost new. The collar of his doublet just over thefore-part of the left shoulder was quit broken asunder, cloth andstiffening, streight downwards, as if cut or chop'd asunder, but with a_Blunt_ tool; only the inward linnen or fustian lineing of it was whole, bywhich, and by the view of the ragged Edges, it seem'd manifest to me, thatit was by the stroak inward (from without) not outwards from within. His _Hat_ was strangely torn, not just on the Crown, but on the side of thehat, and on the brim. On the side of it was a great hole, more than to putin ones fist through it: some part of it being quite struck away, and fromthence divers gashes every way, as if torn, or cut with a _Dull_ tool, andsome of them of a good length, almost quite to the edges of the brim. And, beside these, one or two gashes more, which did not communicate with thehole in the side. This also I judged by a stroke inwards; not so much fromthe view of the edges of those gashes (from which there was scarce anyjudgement to be made either way) but {225} because the lining was not torn, only ript off from the edge of the hat (where it was sow'd on) on thatside, where the hole was made. But his hat not being found upon his head, but at some distance from him, it did not appear, against what part of thehead that hole was made. Upon the rest of his Cloaths, I do not know of any further effect, nor didwe smell any sulphurous scent about them: which might be, _Partly_ becauseit was now a good while after the time, and _Partly_ by reason of theirbeing presently drenched in the water into which he fell. The night following, the three _Doctors_ above mentioned, and my self, withsome Chirurgions (besides a multitude of others) were present at theopening of the head, to see if any thing could be there discover'd; butthere appear'd no sign of contusion; the brain full and in good order; thenerves whole and sound, the vessels of the brain pretty full of Blood. Butnothing was by any of them discern'd to be at all amiss. But it was bycandle-light, and they had not time to make very nice Observations of it(the Body being to be buried by and by) and the croud of People was afurther hindrance. But if any thing had been considerably out of order tothe view, it would surely have been by some of them discover'd. Some ofthem thought, they discern'd a small fissure or crack in the skull; andsome who held it, while it was sawing off, said, they felt it Jarring intheir hands, and there seem'd to the eye something like it, but it was sosmall, as that by candle-light we could not agree it certainly so to be. Some of the _Hair_ on the right Temple was manifestly singed, or burnt; andthe lower part of that Ear blacker, than the parts about it, but soft; andit might be only the settling of the Blood. The upper part of the leftshoulder, and that side of the neck, were also somewhat blacker than therest of the Body, but whether it were by the blow, which broke the collar, and scorch'd the round red spot thereupon, or only by settling of theBlood, I cannot say; yet I think, it might very well be, that both on thehead, and on this side of the neck, there might be a very great blow, and acontusion upon it (and seems to have been so, by the tearing of the hat, and breaking the collar, if not also cracking of the skull) and yet no signof such contusion, because dying so immediately, there was not time for theBlood to gather {226} to the part and stagnate there (which in bruises isthe cause of blackness) and it was but as if such a blow had been given ona Body newly dead; which does not use to cause such a symptom of a bruise, after the Blood ceases to circulate. Having done with, the Head, they open'd the _Breast_, and found thatburning to reach quite through the skin, which was in those scorch'd placeshard and horney, and shrunk up, so as it was not so thick as the soft skinabout it: but no appearance of any thing deeper than the skin; the Musclesnot at all disorder'd or discolour'd (perhaps, upon the reason, that wasbut now said of the Head, Neck and Shoulder). Having then taken off the_Sternum_, the Lungs and Heart appear'd all well, and well-colour'd withoutany disorder. This is the sum of what was observ'd; only that the whole Body was, bynight, very much swell'd, more than in the morning; and smelt very strongand offensively: Which might be by the hotness of the weather, and by theheat of the place occasion'd by the multitude of People. * * * * * _An Experiment to examine, what _Figure_, and _Celerity_ of _Motion_begetteth, or encreaseth _Light_ and _Flame_. _ This was communicated by Dr. _Beale_, as follows; _May_ 5. 1665. Fresh Mackrels were boyl'd in Water, with salt and sweetherbs; and, when the Water was perfectly cold, the next morning, theMackrels were left in the Water for pickle. _May_ 6. More fresh Mackrels were boyl'd in like Water; and _May_ 7. BothWater and Mackrels were put into the former Water, together with the formerMackrels. (Which circumstances I do particularize, because, whether, themixture of the pickle of several ages, and a certain space of time, orwhatever else was necessary, and wanting, the trial did not succeed withlike effect at other times). But now on the next _Munday_ (_May_ 8). Evening, the Cook stirring theWater, to take out some of the Mackrels, found the Water at the firstmotion become very luminous, and the Fish shining through the Water, asadding much to the Light, which the water yielded. The water by the mixtureof Salt and Herbs, {227} in the boyling, was of it self thick and ratherblackish, than of any other clear colour: yet being stirr'd, it shin'd, andall the fish appear'd, more brightly luminous in their own shapes. Wherever the drops of this water (after it was stirr'd) fell on the Ground, or Benches, they shin'd: And the Children took drops in their hands, asbroad as a penny, running with them about the house, and each drop, bothnear and at distance, seem'd by their shining as broad as a six pence, or ashilling, or broader. The Cook turn'd up the side of the Fish, which was lowest, and thence cameno shining: and after the water was for some good time settled, and fullyat rest, it did not shine at all. On _Tuesday_ night (_May_ 9). We repeated the same Trial, and found thesame effects. The water, till it was stirr'd, gave no light, but was thickand dark, as we saw by day-light, and by candle-light. As soon as theCook's hand was thrust into the water, it began to have a glimmering; butbeing gently stirr'd by the hand moving round (as the Dairy-maid do togather the Curds for Cheese) it did so shine, that they, who look'd on itat some distance, from the farther end of another room, thought verily, itwas the shining of the Moon through a Window upon a Vessel of Milk; and bybrisker Circulation it seem'd to flame. The Fish did then shine as well from the Inside, as the Outside, andchiefly from the Throat, and such places, as seem'd a little broken in theboyling. I took a piece that shin'd most, and fitted it as well as I could devise inthe night, both to my great _Microscope_, and afterwards to my little one;but I could discern no light by any of these Glasses; nor from any drops ofthe shining water, when put into the Glasses. And _May_ 10. In thebrightest rayes of the Sun, I examin'd, in my great _Microscope_, a smallbroken piece of the Fish, which shin'd most the night before. We could findnothing on the surface of the Fish very remarkable. It seem'd whitish, andin a manner dried, with deep inequalities. And others, as well as my self, thought, we saw a stream, rather darkish, than luminous, arising like avery small dust from the Fish: And rarely here and there, a very small; andalmost imperceptible sparkle in the Fish. Yet of these _sparkles_ we are_certain_; we numbered them, and agreed in the number, order and place. Ofthe _steam_ I am not confident, but do suspect our Eyes in the {228} brightSun, or that it might be some dust in the Aire. The great _Microscope_ being fitted in the day-light for this piece ofFish, we examin'd it that night, and it yielded no light at all, either bythe view of the Glass, or otherwise. Finding it dry, I thought that the moisture of Spittle, and touching of it, might cause it to shine: and so it did, though but a very little, in a fewsmall sparks, which soon extinguish'd. This we saw with the bare eye; notin the Glass. The Fish were not yet fetide, nor insipid to the best discerning palats:And I caused two Fish to be kept for further Tryal, two or three dayslonger, till they were fetide in very hot weather; and then I expected morebrightness, but could find none, either in the water, by stirring it, or inthe Fish, taken out of the water. And some Trials I made afterwards with other boyl'd Mackrels (as is abovesaid) with like pickle, but failed of the like success. This season serves for many Trials in this kind, and by better_Microscopes_, or better ordered. And in these Vulgarities we may perhapsas well trace out the cause and nature of Light, as in Jewels of greatestvalue, &c. * * * * * _Some Considerations touching a Letter in the _Journal des Scavans_ of _May24. 1666_. _ In _Num. _ 9. Of these _Transactions_ were publish'd the _Schemes_ and_Descriptions_ of certain Ways of _Sounding the Depth of the Sea without aLine_; and of _Fetching up Water from the bottom of it_; together with someExperiments already made with the former of these two Contrivances. TheAuthor of the French _Journal des Scavans_ found good, to insert them bothin his _Journal_ of _May_ 3. But in another of _May_ 24. Intimates, thatthe said _Schemes_ and their _Descriptions_ are not very clear andintelligible (he means, that they were not well understood by _French_Readers) proposing also some Difficulties, relating to that Subject, andesteemed by him necessary to be satisfied, before any use could be made ofthe said Instruments. Upon this occasion, the Author of these _Tracts_ thinks fit, here torepresent, {229} _First_, That _Englishmen_ and such others, as are well versed in the_English_ tongue, find no difficulty in understanding the descriptions ofthese _Engines_, nor in apprehending their structure, exhibited by the_Figures_, especially if notice be taken of the Emendation, expressed atthe end of _Num. _ 10. About the misgraving the _Bended end_ of the_Springing Wire_ (which it seems has not been noted in _France_, tho' thesaid _Num. _ 10 is known to have been seen there a pretty while before their_Journal_ of _May_ 24. Was publish'd). And as for the particular of the_Bucket_, fetching water from the bottom of the Sea, both the _Figure_ andthe annexed _Description_ thereof are so plain and clear, that 'tis somewonder here, that any difficulty of understanding them is pretended by any, that hath but ordinary skill in _Cutts_ and the _English_ language. Meanwhile, that way, which the _French_ Author recommends for this purpose asmore simple, _Videl. A Brass-Pump with double Valves_, is not at allunknown in _England_, nor has bin left untried there; but was foundinconvenient, in respect that the Valves in descending did not fully open, and give the water a free passage through the Cavity of the Vessel, nor inascending shut so close, as to hinder the water from coming in at the top:Whereas by the way proposed in _Num. _ 9. Both is perform'd with great easeand security. _Secondly_, Whereas the _French_ Author is of opinion, that 'tis unknown, how much time a Heavy Body requires to sink in water, according to acertain depth; he may please to take notice, that that hath been made outin _England_ by frequent Experiments; by which, several Depths, found bythis Method of sounding _without_ a Line, were examin'd by trying them overagain in _the same_ place _with_ a Line, after the common way. And as tothat _Quære_ of his, Whether a heavy Body descends in the same _Proportion_of swiftness in _Water_, that it would do in _Air_? The Answer is, that itdoes not; but that, after it is sunk one or two fathoms into the Water, ithas there arrived to its greatest swiftness, and keeps, after that, anequal degree of velocity; the _Resistance_ of the water being then foundequal to the _Endeavour_ of the heavy Body downwards. _Thirdly_, When the same _Author_ alledges that it must be known, when aLight Body reascends from the bottom of the water to {230} the top, in whatproportion of time and swiftness it rises. He seems not to have considered, that in this Experiment, the times of the descent and assent are both takenand computed together; so that for this purpose, there needs not thatnicety, he discourses of. _Fourthly_, Whereas it is further excepted, That this way of SoundingDepths is no new Invention; The answer is ready, that neither is itpretended to be so, in the often quoted _Tract_; it being only intimatedthere, that the manner of performing it, as it is in that place representedand described, is new. _Lastly_, To rectifie the said Author's mistake, as if the instrument offetching up Water from the bottom of the Sea, were chiefly contriv'd, tofind out, Whether in some places of the Sea any _Sweet_ Water is to be metwith at the bottom: There will need no more, than to direct him to the Bookit self _Num. _ 9. Where p. 149. Towards the end, the _First_ use of this_Bucket_ is express'd to be, to know the _degrees of Saltness_ of the Wateraccording to its nearness to the top or bottom; or rather to know theconstitution of the Sea-water in several depths of several _Climates_, which is a matter, much better to be found out by _Trial_, than_Discourse_. Neither is it any where argued in that Book (as the _FrenchJournal_ insinuates) that, because sweet water is found at the Bottom ofthe Sea of _Baharem_, therefore it _must_, but only that it _may_, be foundso elsewhere. And since the same _Journal_ admits, that those Sweetwater-springs, which yield the sweet water, that is found at the saidplace, have been formerly on the _Continent_, far enough from the Sea, which hath afterwards covered them. It will be, it is presumed, lawful toask, Why in many other places there may not be found the like? And besides, how we do know, but that there may be in other parts, Eruptious of largeSprings at the bottom of the Sea, as well as there? * * * * * Printed with Licence for _John Martyn_, and _James Allestry_, Printers tothe Royal-Society. 1666. {231} * * * * * _Num. _ 14. PHILOSOPHICAL_TRANSACTIONS. _ * * * * * _Munday_, _July_ 2. 1666. * * * * * The Contents. _An Account of a _New_ kind of _Baroscope_, which may be call'd _Statical_; and of some Advantages and Conveniencies it hath above the _Mercurial_; communicated by Mr. _Boyle_. The Particular Observations of the Planet _Mars_, formerly intimated to have been made by Mr. _Hook_ in _February_ and _March_ last. Some Observations, made in _Italy_, confirming the former; and withall fixing the _Period_ of the said Planet's Revolution. Observations, lately made at _London_, of the Planet _Jupiter_: as also of _Saturn_. A Relation of a sad Effect of Thunder and Lightning. An Account of some Books, lately publish'd; _videl_. The Relations of divers Curious Voyages, by Mons. _Thevenot_: A Discourse about the Cause of the Inundation of the _Nile_, by Mons. _de la Chambre_, both _French_: De Principiis & Ratiocinatione Geometrarum, Contra Fastum Professerum Geometriæ, by Mr. _Hobbes_: King _Salomons_ Pourtraiture of Old Age, by_ J. Smith, M. D. * * * * * _An Account of a _New_ kind of _Baroscope_, which may be called _Statical_;and of some Advantages and Conveniencies it hath above the _Mercurial_:Communicated, some while since, by the Honourable _Robert Boyle_. _ [Sidenote: * See _Num. 11. P. 185. Phil. Transactions. _] As for the _New_ kind of _Baroscopes_, which, not long agoe, * I intimatedto you, that my haste would not permit me to give you an account off; sinceyour Letters acquaint me, that you still design a Communicating to the{232} Curious as much Information, as may be, in reference to _Baroscopes_;I shall venture to send you some Account of what I did but name (in myformer Letter) to you. [Sidenote: * _The Scales here meant were before competent Eyewitnesses madeto turn manifestly with the thousandth part of a grain. _] Though by a Passage, you may meet with in the 19th and 20th Pages of my_Thermometrical Experiments and Thoughts_, you may find, that I did someyears agoe think upon this New kind of Baroscope; yet the Changes of theAtmosphere's Weight not happening to be then such, as I wish'd, and beingunwilling to deprive my self of all other use of the exactest Ballance *, that I (or perhaps any man) ever had, I confess to you, that successiveavocations put this attempt for two or three years out of my thoughts; tillafterwards returning to a place, where I chanc'd to find two or three pairsof Scales, I had left there, the sight of them brought it into my mind; andthough I were then unable to procure exacter, yet my desire to make theExperiment some amends for so long a neglect, put me upon considering, thatif I provided a _Glass-buble_, more than ordinary large and light, evensuch Ballances, as those, might in some measure perform, what I had triedwith the strangely nice ones above-mention'd. I caused then to be blown at the Flame of a Lamp some _Glass-bubles_ aslarge, thin and light, as I could then procure, and choosing among them, one, that seem'd the least unfit for my turn, I counterpoised it in a pairof Scales, that would loose their _Æquilibrium_ with about the 30th part ofa Grain, and were suspended at a Frame. I placed both the Ballance and theFrame by a good Baroscope, from whence I might learn the present weight ofthe Atmosphere. Then leaving these Instruments together; though the Scales, being no nicer than I have express'd, were not able to shew me all theVariations of the Air's weight that appear'd in the _Mercurial_ Baroscope, yet they did what I expected, by shewing me variations no greater, thanalter'd the height of Quicksilver half a quarter of an Inch, and perhapsmuch smaller than those: Nor did I doubt, that, if I had had either tenderScales, or the means of supplying the experiment with convenientaccommodations, I should have {233} discerned far smaller Alterations ofthe Weight of the Air, since I had the pleasure to see the Buble sometimesin an _æquilibrium_ with the counterpoise; sometimes, when the Atmospherewas high, preponderate so manifestly, that the Scales being gently stirr'd, the Cock would play altogether on that side, at which the Buble was hung;and at other times (when the Air was heavier) that, which was at the firstbut the Counterpoise, would preponderate, and, upon the motion or theBallance, make the Cock vibrate altogether on its side. And this wouldcontinue sometimes many daies together, if the Air so long retain'd thesame measure of gravity; and then (upon other changes) the Buble wouldregain an _æquilibrium_, or a preponderance; so that I had oftentimes thesatisfaction, by looking first upon the _Statical_ Baroscope (as fordistinctions sake it may be call'd) to foretell, whether in the _Mercurial_Baroscope the Liquor were high or low. Which Observations though they holdas well in Winter, and several times in Summer (for I was often absentduring that season) as the Spring, yet the frequency of their Vicissitudes(which perhaps was but accidental) made them more pleasant in the latter ofthese seasons. So that, the matter of Fact having been made out by variety of repeatedObservations, and by sometimes comparing severall of those new _Baroscopes_together, I shall add some of those Notes about this Instrument, whichreadily occur to my memory, reserving the rest till another opportunity. And _First_, if the ground, on which I went in framing this _Baroscope_, bedemanded, the answer in short may be; 1. That, though the Glass-buble, andthe Glass-counterpoise, at the time of their first being weigh'd, be in theAir, wherein they both are weigh'd, exactly of the same weight; yet theyare nothing near of the same bulk; the Buble, by reason of its capaciouscavity (which contains nothing but Air, or something that weighs less thanAir) being perhaps a hundred or two hundred times (for I have notconveniency to measure them) bigger than the Metalline counterpoise. 2. That according to a _Hydrostatical_ Law (which you know I have lately hadoccasion to make out) If two Bodies of equal gravity, but unequal bulk cometo be weigh'd in another _Medium_, they will be no longer {234}equiponderant; but if the new _Medium_ be heavier, the greater Body, asbeing lighter in _Specie_, will loose more of its weight, than the lesserand more compact; but if the new _Medium_ be lighter than the first, thenthe bigger Body will outweigh the lesser; And this disparity, arising fromthe change of _Medium's_, will be so much the greater, by how much thegreater inequality of bulk there is between the Bodies formerlyequiponderant. 3. That, laying these two together, I consider'd, that'twould be all one, as to the effect to be produced, whether the Bodieswere weighed in _Mediums_ of differing gravity, or in the same _Medium_, incase its (_specifick_) gravity were considerably alter'd: And consequently, that since it appear'd by the _Baroscope_, that the weight of the Air wassometimes heavier, and sometimes lighter, the alterations of it, in pointof gravity, from the weight, it was off at first counterpoising of theBuble of it, would _unequally_ affect so large and hollow a Body, as theBuble, and so small and dense a one, as a Metallin weight: And when the Airby an increase of gravity should become a heavier _Medium_, than before, itwould buoy up the Glass more than the Counterpoise; and if it grew lighter, than it was at first, would suffer the former to preponderate: (TheIllustrations and Proof can scarce be added in few words; but, if it bedesired, I may, God permitting, send you them at my next leasure:) Andthough our English Air be about a thousand times lighter, than water, thedifference in weight of so little Air, as is but equal in bulk to a Buble, seem'd to give small hopes, that it would be sensible upon a Ballance; yet, by making the Buble very large and light, I supposed and found the Event, Ihave already related. _Secondly_, The hermetically seal'd Glass-buble, I employed, was of thebigness of a somewhat large _Orange_, and weigh'd about 1. Drachme and 10. Grains. But I thought it very possible, if I had been better furnish'd withconveniencies (wherein I afterwards found, I was not mistaken) to make(among many, that might be expected to miscarry) some, that might bepreferable to this, either for capacity or lightness, or both; especiallyif care be taken, that they be not seal'd up, whilst they are too hot. For, though one would think, that it were {235} advantagious to rarify and driveout the Air as much as is possible, because in such seal'd Bubles the Airit self (as I have elsewhere shewn) has a weight; yet this advantagecountervails not the inconvenience of being obliged to increase the weightof the Glass, which when it includes highly rarified Air, if it be notsomewhat strong, will be broken by the pressure of the External Air, as Ihave sufficiently tryed. _Thirdly_, I would have tryed, whether the _Dryness_ and _Moisture_ of theAir would in any measure have alter'd the weight of the Buble, as well asthe Variation of Gravity produced in the _Atmosphere_ by other causes; butthe extraordinarily constant absence of Fogs, kept me from makingObservations of this kind; save that one morning early, being told of amist, I sent to see (being my self in bed) whether it made the Air so heavyas to buoy up the Buble; but did not learn, that that mist had any sensibleoperation on it. _Fourthly_, By reason of the difficulties and casualties, that may happenabout the procuring and preserving such large and light Bubles, as I havebeen lately mentioning; it may in some cases prove a convenience to beinform'd, That I have sometimes, instead of one sufficiently large Buble, made use of two, that were smaller. And, though a single Buble of competentbignes be much preferable, by reason that a far less quantity and weight ofGlass is requisite to comprise an equal capacity, when the Glass is blowninto a single Buble, than when it is divided into two; yet I found, thatthe employing of two instead of one, did not so ill answer myexspectations, but that they may for a need serve the turn instead of theother; than which they are more easier to be procured; And if the Ballancebe strong enough to bear so much Glass, without being injur'd: by employingtwo or a greater number of large Bubles, the effect may be moreconspicuous, than if only a single Buble (though a very good one) wereemployed. This instrument may be much improved by divers Accommodations, As _First_, There may be fitted to the _Ansa_ (or Checks of the Ballance) anArch (of a Circle) divided into 15. Or 20. Deg. (more or less, according tothe goodness of the Ballance) that the Cock resting over against theseDivisions, may readily {236} and without Calculation shew the quantity ofthe Angle, by which, when the scales propend either way, the Cock declinesfrom the Perpendicular, and the beam from its Horizontall parallelism. _Secondly_, Those, that will be so curious, may, instead of the OrdinaryCounterpoise (of Brass) employ one of Gold, or at least of Lead, whereofthe _latter_ being of equal weight with Brass, is much less in Bulk, andthe _former_ amounts not to half its bigness. _Thirdly_, These parts of the Ballance, that may be made of Copper orBrass, without any prejudice to the exactness, will, by being made of oneof those Mettals, be less subject, than Steel, (which yet, if well hardnedand polish'd, may last good a great while) to rust with long standing. _Fourthly_, Instead of the scales, the Buble may be hung at one end of theBeam, and only a Counterpoise to it at the other, that the Beam may not beburthen'd with unnecessary weight. _Fifthly_, The whole instrument, if placed in a small Frame, like a squareLanthorn with Glass-windows, and a hole at the top for the Commerce of theinternal and external Air, will be more free from dust, and irregularagitations; to the latter of which, it will otherwise be sometimesincident. _Sixthly_, This instrument being accommodated with a light Wheele and anIndex (such as have been applyed by the excellent Dr. _Chr. Wren_ to openWeather glasses, and by the ingenious Mr. _Hook_ to _Baroscopes_) may bemade to shew much more minute variations, than otherwise. _Seventhly_, And the length of the Beam, and exquisitness of the Ballance, may easily, _without_ any of the foregoing helps (and much more _with_them) make the instrument far exacter, than any of those, I was reduced toemploy. And to these Accommodations divers others may be suggested by afarther consideration of the nature of the thing, and a longer practice. Though in some respects this _Statical_ Baroscope be inferior to the_Mercurial_; yet in others it has its own advantages and convenienciesabove it. And 1: It confirms _ad oculum_ our former Doctrine, that the falling andrising of the _Mercury_ depends upon the varying weight of the Atmosphere;since in this Baroscope it cannot {237} be pretended, that a _Fuga vacui_, or a _Funiculus_, is the cause of the changes, we observe. 2. It shews, that not only the Air has weight, but a more considerable one, than someLearned men, who will allow me to have prov'd, it has some weight, willadmit; since even the variation of weight in so small a quantity of Air, asis but equal in bulk to an _Orange_, is manifestly discoverable upon suchBalances, as are none of the nicest. 3. This _Statical_ Baroscope willoftentimes be more parable, than the other: For many will finde it moreeasie, to procure a good pair of Gold-scales, and a Buble or two, than along Cane seal'd, a quantity of _Quick-silver_, and all the other requisitsof the _Mercurial_ Baroscope; especially if we comprise the trouble andskill, that is requisite to free the deserted part of the Tube from Air. 4. And whereas the difficulty of removing the _Mercurial_ Instrument has keptmen from so much as attempting to do it, even to neighbouring places; theEssential parts of the _Scale_-Baroscope (for the Frame is none of them)may very easily in a little room be carried, whither one will, without thehazard of being spoil'd or injur'd. 5. There is not in _Statical_Baroscopes, as in the other, a danger of uncertainty, as to the goodness ofthe Instruments, by reason, that in _these_ the Air is, in some more, andin some less perfectly excluded; whereas in _those_, that consideration hasno place. (And by the way, I have sometimes, upon this account, been ableto discover by our new Baroscope, that an esteem'd _Mercurial_ one, towhich I compared it, was not well freed from Air. ) 6. It being, as Iformerly intimated, very possible to discover _Hydrostatically_, both thebigness of the Buble, and the Contents of the cavity, and the weight anddimensions of the Glassie substance (which together with the included Airmake up the Buble, ) much may be discover'd by this Instrument, as to theWeight of the Air, _absolute_ or _respective_. For, when the _Quick-silver_in the _Mercurial_ Baroscope is either very high, or very low, or at amiddle station between its greatest and least height, bringing the_Scale_-Barometer to an exact _Æquilibrium_ (1 with very minute divisionsof a Graine, ) you may, by watchfully observing, when the _Mercury_ is risenor faln just an inch, or a fourth, of half an inch &c. And putting in thelike minute divisions of a Grain to the lighter Scale, till you have againbrought the Ballance to an {238} exquisit _Æquilibrium_; you may, I say, determine, What known weight in the _Statical_ Baroscope answers suchdeterminate Altitudes of the ascending and descending Quick-silver in the_Mercurial_. And if the Ballance be accommodated with a divided Arch, or aWheel and Index, these Observations will assist you for the future todetermine readily, by seeing the inclination of the Cock or the degreemark'd by the Index, what pollency the Buble hath, by the change of the_Atmospheres_ weight, acquired or lost. Some Observations of this nature Iwatchfully made, sometimes putting in a 64^{th. } sometimes a 32^{th. }sometimes a 16^{th. } and sometimes heavier parts of a Grain, to the lighterScale. But one, that knew not, for what uses those little papers were, coming to a window, where my Baroscopes stood, so unluckily shook them outof the Scales, and confounded them, that he robb'd me of the opportunity ofmaking the nice Observations I intended, though I had the satisfaction ofseeing, that they were to be made. 7. By this _Statical_ Instrument we maybe assisted to compare the _Mercurial_ Baroscopes of _several_ places(though never so distant) and to make some Estimates of the Gravities ofthe Air therein. As if, for instance, I have found by Observation, that theBuble, I employ, (and one may have divers Bubles of several sizes, that theone may repaire any mischance, that may happen to another) weigh'd just aDrachme, when the _Mercurial_ Cylinder was at the height of 29½ inches(which in some places I have found a _moderate_ altitude;) and that theAddition of the 16th part of a gr. Is requisite to keep the Buble in an_Æquilibrium_, when the _Mercury_ is risen an 8th, or any determinate partof an inch above the former station: When I come to another place, wherethere is a _Mercurial_ Barometer, as well freed from Air as mine (for thatmust be supposed) if taking out my _Scale_ instrument, it appeare to weighprecisely a Drachme, and the _Mercury_ in the Baroscope there stand at just29½ inches, we may conclude the Gravity of the Atmosphere not to besensibly unequal in both those two places, though very distant. And thoughthere be no Baroscope there, yet if there be an additional weight, as forinstance, the 16th part of a Grain requisite to be added to the Buble, tobring the scales to an _Æquilibrium_, it will appear that the Air at thissecond place is, at that time {239} so much heavier, than the Air of theformer place was, when the _Mercury_ stood at 29½ inches. But in making such comparisons, we must not forget to consider theSituation of the several places, if we mean to make Estimates not only ofthe weight of the Atmosphere, but of the weight and density of the Air. For, though the Scales wil shew (as has been said) whether there be adifference of weight in the Atmosphere at the two places; yet, if one ofthem be in a Vale or bottom, and the other on the top or some elevated partof a Hill, it is not to be exspected, that the Atmosphere, in this latterplace, should gravitate as much, as the Atmosphere in the former, on whicha longer Pillar of Air does lean or weigh. And the mention, I have made of the differing Situation of Places, puts mein mind of something, that may prove another use of our _Statical_Baroscope, and which I had thoughts of making tryal off, but wasAccidentally hindred from the opportunity of doing it. Namely, that byexactly poysing the Buble at the foot of a high Steeple or Hill, andcarrying it in its close Frame to the top, one may, by the weight requisiteto be added to Counterpoise there to bring the Beam to its Horizontalposition, observe the difference of the weight of the Air at the bottom, and at the top; and, in case the Hill be high enough, at some intermediateStations. But how far this may assist men, to estimate the _Absolute_ or_Comparative_ height of Mountains, and other elevated Places; and whatother Uses the Instrument may be put to, when it is duly improved; and theCautions, that may be requisite in the several cases, that shall beproposed, I must leave to more leasure, and farther Consideration. * * * * * _The Particulars of those Observations of the Planet _Mars_, formerlyintimated to have been made at _London_ in the Months of _February_ and_March_ A. _ 1665/6. To perform, what was promised _Num. _ 11. Of these Papers, _pag. _ 198; 'tisthought fit now to publish the Particular Observations, concerning thespots in _Mars_, and their motion, as they were made with a 36 footTelescope, and produced in {240} writing before the _Royal Society_, the 28_March_ 1666. By Mr. _Hook_, as follows; Having a great desire (saith he) to observe the Body of _Mars_, whilst_Acronycal_ and _Retrograde_ (having formerly with a Glass of about 12. Foot long, observ'd some kind of Spots in the Face of it, ) though it be notat present in the _Perihelium_ of its Orbe, but nearer its _Aphelium_, yetI found, that the Face of it, when neer its Opposition to the Sun (with aCharge, the 36. Foot-glass, I made use off, would well bear) appear'd verynear as big, as that of the Moon to the _naked_ eye; which I found, bycomparing it with the Full Moon, near adjoyning to it, _March_ 10. But such had been the ill disposition of the Air for several nights, thatfrom more than 20. Observations of it, which I had made since its being_Retrograde_, I could find nothing of satisfaction, though I oftenimagin'd, I saw Spots, yet the _Inflective veins_ of the Air (if I may socall those parts, which, being interspers'd up and down in it, have agreater or less Refractive power, than the Air next adjoyning, with whichthey are mixt) did make it so confus'd and glaring, that I could notconclude upon any thing. On the third of _March_, though the Air were still bad enough yet I couldsee now and then the Body of _Mars_ appearing of the form A: which Ipresently described by a _Scheme_; and about 10. Minutes after, as exactlyrepresenting what I saw through the Glass, as I could, I drew the _Scheme_B. This I was sufficiently satisfied (by very often observing it throughthe Tube, and changing my Eye into various positions, that so there mightbe no kind of Fallacy in it) could be nothing else, but some more _Dusky_and _Spotted_ parts of the Face of this Planet. _March_ 10. Finding the Air very bad, I made use of a very shallowEye-glass, as finding nothing _Distinct_ with the greater _Charge_; and sawthe appearance of it as in C, which I imagin'd, might be the Representationof the former Spots by a lesser charge. About 3 of the Clock the samemorning, the Air being _very bad_ (though to appearance _exceeding clear_, and causing all the Stars to twinckle, and the minute Stars to appear verythick) the body seem'd like _D_; which I still suppos'd to be {241} theRepresentation of the same Spots through a more confused and glaring Air. But observing _March_ 21. I was surprised to find the Air (though not soclear, as to the appearance of small Stars) so _exceeding transparent_, andthe Face of _Mars_ so very well _defined_, and round, and distinct, that Icould manifestly see it of the shape in E. About half an hour after Nine atnight. The _Triangular_ spot on the right side (as it was inverted by theTelescope, according to the appearances, through with all the preceeding_Figures_ are drawn) appear'd very black and distinct, the other towardsthe left more dim; but both of them sufficiently plain and defin'd. About aquarter before 12. Of the Clock the same night, I observ'd it again withthe same Glass, and found the appearance exactly, as in F; which I imagin'dto shew me a _Motion_ of the former triangular spot: But designing toobserve it again about 3. Of the Clock the same Morning, I was hindred bycloudy weather. But _March_ 22. About half an hour after 8. At night, finding the sameSpots in the same posture, I concluded, that the preceeding Observation wasonly the appearance of the same Spots at another height and thickness ofthe Air: And thought my self confirm'd in this Opinion, by finding them inmuch the same posture, _March_ 23. About half an hour after 9. Though theAir was nothing so good as before. And though I desired to make Observations, about 3. Of the Clock thosemornings; yet something or other interven'd, that hindred me, till _March_28. About 3 of the Clock, the Air being light (in weight) though moist anda little hazy; when I plainly saw it, to have the form, represented in I;which is not reconcileable with the other Appearances, unless we allow a_Turbinated_ motion of _Mars_ upon its Center: Which, if such there be, from the Observations made _March_ 21. 22. And 23. We may guess it to beonce or twice in about 24. Hours unless it may have some kind of_Librating_ motion; which seems not so likely. Now, whether certainly so ornot, I shall endeavour, as oft as I have opportunity, further to observe. [Illustration] A particular direction to the _Figures_ mentioned in the precedentdiscourse. A. _March _3^{d. } 00^{h. } 20^{m. }_ in the morning: the Air having many{242} inflecting parts dispersed up and down in it; by the _WheelBarometer_, heavy, _ B. _Another Scheme, which I drew from my Observation, about 10. Minutesafter, the same morning. Both these were observed with a very deepEye-glass. _ C. _March_ 10^{d. } 00^{h. } 20^{m. } _in the morning: the Air heavy andinflective. Use was made of a shallow or ordinary Charge. _ D. _March_ 10^{d. } 3^{h. } 00^m _in the Morning; the Air very heavy andInflective, which made it glare and radiate, and be more confused, thanabout 3. Hours before. A shallow Charge. _ E. _March_ 21^{d. } 9½^{h. } _post merid; the Air light (in weight) andclear, without inflecting parts; the Face appear'd most distinctly of thisForme. A shallow Charge. _ F. _March_ 21^{d. } 11¾^{h. } _post merid; the Air continuing very light andclear, without inflecting vapours. A shallow Charge. _ G. _March_ 22^{d. } 8½^{h. } _post mer. The Air clear, with few inflectingveins in it, and indifferent light. A shallow Charge. _ H. _March_ 23^{d. } 9½^{h. } _post mer. The Air pretty light, but moist, andsomewhat thick and hazy, but seem'd to have but few veins, or inflectingparts. _ I. _March_ 28^{d. } 3^{h. } _p. M. Much the same kind of Air with that ofMarch 23; light, moist, and a little hazy, with some very few veins. _ * * * * * _Observations made in _Italy_, confirming the former, and withall fixingthe _Period_ of the Revolution of _Mars_. _ These Observations we shall summarily present the Curious in these partswith, as they were lately presented (by Letter from his Excellency theAmbassadour of _Venice_, now residing at the Court of _France_) to the_Royal Society_, in some printed sheets of Paper, entituled, _MARTIS, circaAxem proprium Revolubilis, Observationes, BONONIÆ à JO. DOMINICO CASSINOhabitæ;_ come to hand _June_ 3. 1666. In these Papers the Excellent _Cassini_ affirms; 1. That with a _Telescope_ of 24. _Palmes_, or of about 16 _Foot_, wroughtafter S. _Campani's_ way, he began to observe _February_ 6. 1666 (st. N. ) inthe morning, and saw two dark Spots in the _first_ Face of _Mars. _ {243} 2. That with the same Glass he observ'd _Febr. _ 14/24. In the Evening, inthe _other_ Face of this Planet, two other Spots, like those of the first, but bigger. 3. That afterwards continuing the Observations, he found the Spots of thesetwo Faces to turn by little and little from _East_ to _West_, and to returnat last to the same situation, wherein he had seen them first. 4. That S. _Campani_, having also observ'd at _Rome_ with Glasses of 50. _Palmes_ or about 35 _Foot_, likewise of his own contrivance, had seen inthe same Planet the same _Phenomena_. 5. That sometimes he hath seen, during the same night, the two Faces of_Mars_, one, in the Evening, the other in the Morning. 6. That the Motion of these Spots in the inferior part of the apparentHemisphere of _Mars_, is made from _East_ to _West_, as that of all theother Celestial Bodies, and is peform'd by Parallels, that decline _much_from the _Equator_, and _little_ from the _Ecliptick_. 7. That the Spots return the next day to the same situation, 40. Minutslater, than the day before; so that in every 36. Or 37. Daies, about thesame hour, they come again to the same place. 8. He promises shortly to give us the particular _Tables_ of this Motionand of its Inequalities, together with the _Ephemerides_ themselves. 9. He represents, that some other _Astronomers_ have also made at _Rome_several Observations of these Spots of _Mars_, from _March 14/24. _ to_March 20/30. _ with Glasses, wrought by _Eustachio Divini_, of 25. And 45. Palmes; Which Spots he makes little differing from his own, of the firstFace; as will by and by appear, by the direction to the _Schemes_. 10. But he adds, that those other _Roman_ Astronomers, that have observ'dwith _Divini's_ Glasses, will have the Conversion of _Mars_ to beperformed, not in 24 h, 40 m. (as he maintains it is) but in about 13 h. 11. And to evince, that they are mistaken in these Observations of theirs;he alledges, That they assure that the Spots, which they have seen in thisPlanet, (by an _Eustachian_ Telescope) the 20/30 of _March_, were small, very distant from one another, remote from the middle of the Disk, and the_Oriental_ Spot was less, than the _Occidental_ (as is represented by theFig. O; like that of the first Face of _Mars_. ) whereas, on the contrary, {244} He (_Cassini_) pretends to evidence by his Observations, made at thesame time at _Bononia_, that, the same day and hour, those Spots were verylarge, neer one another, in the midst of the Disk, the Oriental bigger thanthe Occidental (as appears by _Fig. _ P, which is that of the second Face of_Mars_. ) 12. Besides, he declares, that those _Astronomers_ were too hasty, indetermining, after 5 or 6 Observations only, in how much time _Mars_finish's his Revolution; and denies it to be perform'd in 13 hours: adding, that, though Himself had observ'd for a much longer time, than they; yet hedurst not for a great while define, Whether _Mars_ made but _one_ Turn in24 hours 40 minuts or _two_; and that all, that he could, for a long timeaffirm, was onely this, that after 24 h. 40 m. This Planet appear'd in thesame manner he did before. 13. But since those first Observations, He affirms to have found cause todetermine, that the Period of this Conversion is made in the said space of24 h. 40 m; and not oftner than once within that time; Alledging for proof; 1. That, whereas _Febr. _ 6. (st. N. ) he saw the Spots of the first Face of_Mars_, moving from eleven of the Clock in the night, until break of day, they appear'd not afterwards in the Evening after the rising of that Planet(witness several intelligent persons, which he names, that were present atthe Observations) Whence he infers, that after 12 hours and 20 minuts, thesame Spots did not come about; since that the same, which in the morningwere seen in the middle, upon the rising of _Mars_; after 13 or 14 hours, might have appear'd neer the Occidental Limb. But, because he might beimposed upon by Vapors, whilst _Mars_ was yet so neer the _Horizon_, hegives this other determination, _vid. _ 2. Whereas he saw the first Face of _Mars_ the 6 of _February_ at 11 of theclock of the night following; he did not see the same after 18 daies at thesame hour; as he ought to have done, if the Period were absolved in thespace of 12 h. 20 m. [Illustration] 3. Again, whereas he saw _Febr. _ 24. In the Evening, the other Face of_Mars_, he could not see the same, the 13. And 15. Day of _March_, to witafter 17 and 19 days; as he should have done, if the Revolution were madein the newly mention'd time. 4. Again, whereas the 27. Of _March_ in the Evening he saw {245} the secondFace of _Mars_, he could not see it the 14. And 16. Of _April_. From all which Observations he Judges it to be evident, that the Period ofthis Planets Revolution is not perform'd in the space of 12. Hours 20, minutes, but in about 24 hours 40 minutes; more exactly to be determin'd bycomparing distant Observations: And that those who affirm the former, musthave been deceived by not well distinguishing the two Faces, but thathaving seen the second, taken it for the first. All which he concludes with this Advertisement, that, when he defines thetime of the Revolution of _Mars_, he does not speak of its _Mean_Revolution, but onely of that, which he observ'd, whilst _Mars_ wasopposite to the Sun; which is the shortest of all. _The Figures of the _Principal_ Observations, represented in the Book here discoursed of, may be seen in the annexed _Scheme_; _videl. __ K. _One of the Faces of _Mars_, as S. _Cassini_ observed it _March 3. (_st. N. _) 1666_ in the Evening, with a Glass of 24 Palmes. _ L. _The other Face, as he saw it _Febr. 14/24_ in the Evening. _ M. _The first Face, as S. _Campani_ saw at Rome, _March 3. 1666_. In theEvening, with a Glass of 50 Palmes. _ N. _The second Face, as the same _Campani_ observed it _March 18/28_. Inthe Evening. _ O. _The figure of _Mars_ as it was seen at _Rome_ by a Telescope of_Divini_ of 45 Palmes, _March 20/30_. _ P. _The Figure of the said Planet, as it was seen the same day and hour atBononia by _Cassini_; being that of the second Face. _ * * * * * _Some Observations lately made at _London_ concerning the Planet_Jupiter_. _ These, as they were made, so they were imparted, by Mr. _Hook_, as follows: [Illustration] A. 1666, _June_ 26. Between 3. And 4. Of the Clock in the morning, Iobserved the Body of _Jupiter_ through a 60 foot-glass, and found theapparent Diameter of it through the Tube, to be somewhat more than 2. Degrees, that is, about four {246} times as big, as the Diameter of the_Moon_ appears to the _naked_ Eye. I saw the Limb pretty round, and verywell defin'd without radiation. The parts of the _Phasis_ of it had variousdegrees of Light. About a and f, the _North_ and _South_ poles of it (inthe _Fig Q. _) 'twas somewhat darker, and by degrees it grew brightertowards b. And e, two Belts or Zones; the one of which (b) was a small dark_Belt_ crossing the Body Southward; Adjoyning to which was a smal Line of asomewhat lighter part; and below that again, Southwards, was the greatblack _Belt c_. Between that, and e, the other smaller black Belt, was apretty large and bright _Zone_; but the middle d, was somewhat darker thanthe edges. I perceiv'd about 3^{h. } 15^{m. } near the middle of this, a very_dark round Spot_, like that represented at g, which was not to beperceiv'd about half an hour before: And I observed it, in about 10. Minutes time to be gotten almost to d, keeping equal distance from the_Satelles h_, which moved also Westwardly, and was joyn'd to the Disk at i, at 3^{h. } 25^{m. } After which, the Air growing very hazy, and (as appearedby the _Baroscope_) very light also (in weight) I could not observe it: Sothat it was sufficiently evident, that this black Spot was nothing else, save the shadow of the _Satelles h_, Eclipsing a part of the Face ofJupiter. About two hours before, I had observed a large darker spot in thebigger _Belt_ about k, which in about an hour or little more (for I did notexactly observe the time, nor draw the _Figure_ of it) moving Westwards, disappear'd. About a week before, I discover'd also, together with a Spotin the _Belt c_, another Spot in the _Belt e_, which kept the same way andvelocity with that of the _Belt c_. The other three _Satellites_ in thetime of this Eclipse, made by the _Satelles_, were Westwards of the Body of_Jupiter_; appearing as bright through the Tube, as the Body of _Jupiter_did to the naked Eye, and I was able to see them longer through the Tube, after the day-light came on, than I was able to see the Body of _Jupiter_with my naked eye. * * * * * _A late Observation about Saturn made by the same. _ [Illustration] _June_ 29 1666. Between 11. And 12. At night I observed the Body of_Saturn_ through a 60. Foot Telescope, and found it {247} exactly of theshape represented in the _Figure_ R. The _Ring_ appear'd of a somewhatbrighter Light than the _Body_; and the black lines a a, crossing the Ring, and b b crossing the Body (whether Shadows or not, I dispute not) wereplainly visible: whence I could manifestly see, that the _Souther_-mostpart of the Ring was on _this_ side of the Body, and the _Northern_ part, behind, or covered by the Body. * * * * * _A Relation of a sad effect of Thunder and Lightning:_ This Relation was written by that worthy Gentleman, _Thomas Neale_ Esquire, (the then _High Sheriff_ of the County of _Hampshire_, when this disasterhapned) to a Friend of his in _London_, as follows; On the 24 of _January_ 1665/6, one Mr. _Brooks_ of _Hampshire_, going from_Winchester_ towards his house near _Andover_ in very bad Weather, washimself slain by Lightning, and the Horse, he rode on, under him. For abouta mile from _Winchester_ he was found with his Face beaten into the ground, one leg in the stirrup, the other in the Horses mane; his Cloaths all burntoff his back, not a piece as big as a handkerchief left intire, and hishair and all his body singed. With the force, that struck him down, hisnose was beaten into his face, and his Chin into his Breast; where was awound cut almost as low, as to his Navil; and his cloaths being, asaforesaid, torn, the pieces were so scatter'd and consum'd, that not enoughto fill the crown of a hat could be found. His gloves were whole, but hishands in them sing'd to the bone. The hip-bone and shoulder of his Horseburn't and bruised; and his saddle torn in little pieces. This was whatappear'd to the Coroners inquest, and so is likely to be as near truth, asany is to be had. _So far this Letter_: Which, if it had come soon enough to the hands of the_Publisher_, would have been joyned to a like _Relation_, inserted in thenext foregoing Papers (_Num. _ 13. ) of an accident hapn'd at a later time. With both which may be compared the Account, formerly published in Latin bythe Learned Dr. _Charleton_, concerning the Boy, that was {248}Thunder-struck near _Nantwich in Cheshire;_ the Title of the Book being_Anatome Pueride Cælo tacti_: such Relations, when truly made, welldeserving to be carefully recorded for farther consideration. * * * * * _Of some Books lately publish't. _ _RELATIONS OF DIVERS CURIOUS VOYAGES_, by _Mons. Thevenot_, the third_Tome_, in _French_. This Book contains chiefly, the Ambassie of the_Dutch_ into _China_, translated out of the Dutch manuscript: AGeographical description of _China_, translated out of a Chinese Author by_Martinius_: And the Account, which the Directors of the Dutch East-IndiaCompany made to the States General, touching the state of affairs in theEast-Indies, when their late Fleet parted from thence. To touch some thingsof a _Geographical_ and _Philosophical_ nature, contained therein, we shalltake notice; 1. How the Kingdom of _China_ is peopled; there being according to the bestcomputation (which is there made with singular care) above 58 millions ofMen, not counting Magistrates, Soldiers, Priests, Eunuchs, Women andChildren; so that it may not be altogether strange, if one should affirm, there were 200 millions of people, of all sorts, in that Kingdom. 2. That _Catay_ is nothing else, but the _Six_ Northern Provinces of_China_, separated from the other _Nine_, by the great River _KIANG_; andthat the City _Cambalu_ is the same with that of _Peking_; the _Tartars_, who carry every three years their Tribute to the Emperor of _China_, constantly calling the said Provinces and City by those names of _Catay_, and _Cambalu_. 3. That _China_ is so well furnisht with Rivers, and cut Channels, that menmay go from the most Southern to the most Northern part thereof by water, except one daies journey; as the Dutch Ambassadours did, embarking at_Canton_, which is 23d. 48m. Northern Latitude, and landing at _Peking_, which is about 40d; having only travell'd one daies journey over someMountains of the Province _Kiamsi_. 4. That the people of _China_ are exceeding industrious {249} Husbandmenmaking, among other waies of improving their soile, great use of Flouding. 5. That the _Physicians_ of _China_ do cure Sicknesses with much ease, andin a short time: That they have very ancient Books of the nature andvertues of Herbs, Trees and Stones: That their Modern Physicians (as wellas their Ancient ones did) write of the Prognosticks, Causes, Effects, &c. Of Diseases. That their Remedies consist for the most part of _Simples_ and_Decoctions_, _Cauteries_, _Frictions_; without the use of _Bloud letting:_That they have such an excellent skill and method in feeling the _Pulse_, that by the means thereof they discover even the most latent causes ofDiseases; taking a good half hour, when they visit a Patient, in feelingand examining his Pulse: That they prescribe much the use of _The_; and thedrinking alwayes warme, whatever they drink: To the custome of both whichit's imputed, that the inhabitants of _China_ do spit very little, nor aresubject to the Stone or Gout: That they prise highly the Root _Ginseng_, asan extraordinary Restorative and Cordiall, recovering frequently with itagonizing persons; one pound of it being paid with 3 pounds of silver. Asfor their _Chymists_, (of which they have also good store) they go beyondours, promising not only to make Gold, but to give Immortality. 6. That their _Nobility_ is raised from Learning and Knowledge, withoutregard to Bloud or Parentage, excepting the Royall Family. 7. That in _CHEKIAN_, a maritime Province, whence is the shortest cut of_China_ to _Japan_, is the best and plentifullest _Silk-trade_ in theworld: And that there every year the Mulberries are cutt, and kept down, that they grow not into Trees for the easier gathering of the Leaves, therebeing a _double_ Silk-harvest in that Country, as there is in severallother parts of the East-indies; (both which there is hope, will shortly beimitated in _Virginia_. ) 8. That the way of making _Porcelane_ is this: (_Which is the ratherinserted here, because it agrees so well with an Account, we received awhile since from a very Curious and intelligent Person of Amsterdam. _)There is in the Province of _Nankin_ a Town, call'd {250} _Goesifols_whence they draw the Earth for _Porcelaine_, which is found between theRocks of Mountains. This Earth they beat very small, and stamp it to a veryfine Powder, and then put it into Tubs fill'd with water; where the finestpart sinks to the bottom. Afterwards 'tis kneaded in the form of smallCubes, of the weight of about 3. _Catti_ (a _Catti_ being 20 Ounces. ) Thesepieces thus wrought are sold to the people, that commonly in great numbersfetch them, coming from the Town _Sintesimo_ (otherwise _Jontiou_) in theProvince of _Kiansy_, being about 50 miles distant from _Wotsing_, neer theCity _KIANSY_; which people transport them to their homes, and there bakethem in this manner: They heat their Ovens well, for the space of 15 daiessuccessively, and then keep them so close, that no Air may get in; andafter 15 _other_ daies are pass'd, they open the Oven in the presence of anOfficer, who takes every fifth vessel of each fashion for the service ofthe Emperor: Which done, the rest is sold to those of _Ucienien_, whence itis transported all over the Country. So that the Earth is not prepared, in_Nankin_, where 'tis found, because the people of that Province have notthe skill of working it, as the other above-mention'd; who also alone havethe Art of coloring it, which they keep as a great Secret, not teaching itto any, but their Children and next Kindred. 9. That _Musk_ is nothing else, but the Testicles of a Beast like a Dear, found in the Province of _Honan_; and that, when tis good and unmixt, as itcomes from the Animal, they sell it even in _Nankin_ and _Pekin_, for 30. Or 35. _Teyls_ (that is, about so many Crowns) the _Catti_. Many other curious informations might be borrow'd from this Author, concerning the Customs, Studies, Exercises of the _Chinese_; of the numberof the people of each Province; of the Natural productions of the Earth andRivers there; of the Structure and Antiquity of their Wall; of theMagnificence of their Porcelain Tower &c. ; but, remitting for these thingsto the Book it self, we shal only add a piece of Oeconomy, used by the_Holland_-Merchants in their Commerce with _China_, which is, that they dryabundance of Sage-leaves, role them up, and {251} prepare them like _The_, and carrying it to _China_, as a rare drogue, get for one pound of it, fourtimes as much _The_. _A DISCOURSE ABOUT THE CAUSES OF THE INUNDATION OF THE NILE_, in _French_. The Author of this Book is Monseiur _dela Chambre_, who being perswadedfrom several Circumstances, that accompany the Overflowing of this River, that it cannot proceed from Rain, ventures to assign for a Cause of _it_, and of all the other effects that happen at the time of its swelling, the_Niter_, wherewith that water abounds. The discourse having six parts, the Author endeavours to shew in the _First_, that the Waters of the _Nile_ are Nitrous, explicating the Natureof Salt, and Saltpeter, and imputing the fertility of the Earth, as well usthe fecundity of Animals, to Salt. Where he shews, that all things, thatserve to improve Land, are full of Salt; and that 'tis observ'd, that grainsteep'd in Vrine, before sowing, rises sooner, and becomes fuller andstronger, than else. Adding, that that, which renders the Seed of Animalsprolifick, is, that one of the _Spermatick_ veins hath its Origine from the_Emulgent_, through which the Nitrous and Saline Serosities, that dischargethemselves into the Kidneys and Bladder, do pass. In the _Second_, he examins, what is Fermentation, and how 'tis perform'd;affirming, that, what thrusts forth Plants in the Spring, is, that theEarth being fermented by the _Niter_, it harbours, the Nitrous spiritsinsinuate themselves into their Pores. In the _Third_ he treats of all the Circumstances, observable in theInundation of the Nile. 'Tis affirm'd, that 3 or 4 days before that Riverbegins to overflow, all its water is troubled: that then there falls acertain Dew, which hath a fermenting vertue, and leavens a Paste exposed tothe Air: that the Mud, which has been drawn out of the water, growsheavier, when the overflowing begins, then it was before, and that by theincrease of the weight of that Mud, they judge of the greatness of theapproaching inundation. The Author pretends, that {252} the Niter, whichthe _Nile_ is stored with, is the cause of all these strange effects, andof many others, by him alledged. For, _saith he_, when the Nitre is heatedby the heat of the Sun, it ferments, and mingling with the water, troublesit, and swells it, and makes it pass beyond its banks; after the samemanner, as the Spirits in new Wine render it troubled, and make it boyle inthe vessel. And it seems not likely to him, that the Mud, found in the_Nile_, should come a far off; for then it would at last so raise the banksof this River, that it would not be able to overflow them any longer. Whereas 'tis more than 2000 years, that the banks thereof are not grownhigher, there being now requisite but 16. Cubits for overflowing the Land, no more than there was in the time of _Herodotus_. Which shews, _saith he_, that this Mud is nothing but a volatil _Niter_, which exhaling, doth notincrease the Earth. As for the _Ægyptian_ Dew, and the increase of theweight of the Mud, he adscribes them to the same Cause. For the spirits ofNitre abounding in the _Nile_, when raised into the Air with the vapors, that exhale continually from this River, there is made out of theirmixture, a Dew, that refreshes the Air, makes sickness to cease, andproduces all those admirable effects, that make the _Ægyptians_ wish for itso passionately. And the same spirits of Niter, being joyned to the Paste, and to the Mud, raise the one, and augment the weight of the other. That, which Mr. _Buratini_ observes, that at the time of this inundation, theNiter-pits of the neighboring places vomit out liquid Niter, and that onemay see issue out of the Earth abundance of Chrystals of Nitre, is alledgedto fortify this conjecture; Which is yet more confirm'd by the Fertility, communicated to the Earth by the Mud of this River. For, plants do growthere in such abundance, that they would choak one another, if it were notremedied by throwing Sand upon the Fields; insomuch that the _Ægyptians_must take as much pains to spread Sand to lessen the fatness of their Land, as other Nations do, to spread dung or other manure upon theirs to increasethe fatness. In the _Fourth_ and _Fifth_, the Author undertakes to prove, that all thosestrange effects cannot be attributed to Rain or Snow, {253} and that theoverflowing of the _Nile_ always happens at a certain day. In the _Last_, he alledges some Relations, serving to confirm his Opinion;Which are too long here to insist upon. _DE PRINCIPIIS ET RATIOCINATIONE GEOMETRARUM, Contra Fastum ProfessorumGeometriæ;_ Authore _Thoma Hobbes_. It seems, that this Author is angrywith all Geometricians, but himself; yea he plainly saith in the dedicationof his Book, that _he invades the whole Nation of them_; and unwilling, itseems, to be call'd to an account for doing so; He will acknowledge nojudge of _this_ Age; but is full of hopes, that posterity will pronouncefor him. Mean while he ventures to advance this _Dilemma_; _Eorum qui deiisdem rebus mecum aliquid ediderunt, aut solus insanio Ego, aut solus noninsanio; tertium enim non est, nisi (quod dicet forte aliquis) insaniamusomnes. _ Doubtless, one of these will be granted him. As to the Book it self, he professes, that he doth not write it against_Geometry_, but _Geometers_; and that his design in it is, to shew, Thatthere is no less uncertainty and falsity in the writings of_Mathematicians_, than there is in those of _Naturalists_, _Moralists_, &c. , though he judges, that _Physicks_, _Ethicks_, _Politicks_, if theywere well demonstrated, would be as certain as the _Mathematicks_. Attacking the Mathematical Principles as they are found in Books, andwithall some Demonstrations, he takes to task _Euclid_ himself, instead ofall, as the Master of all Geometricians, and with him his best interpreter, _Clavius_, examining in the _First_ place, the _Principles_ of _Euclid_:_Secondly_, Declaring false, what is superstructed upon them, whether by_Euclid_, or _Clavius_, or any _Geometer_ whatsoever that hath made use ofthose or other (as he is pleased to entitle them) _false_ Principles. _Thirdly_, Pretending, that he means so to combat all, both Principles andDemonstrations, undertaken by him, as that he will substitute better intheir room, least he should seem to undermine the Science it selfe. {254} The particulars, which he undertakes to reform, are, _Punctum. _ _Linea. _ _Terminus. _ _Linea Recta. _ _Superficies. _ _Superficiei Termini. _ _Superficies Plana, _ _Angulus_ (Where he is large upon the _Angulus Contactus. _) _Petitio prima Elem. 1. Euclidis. _ _Ratio. _ _Radix & Latus. _ _Prop. 16. El. 3. _ _Dimensio Circuli. _ _Magnitudo Circuli Hugeniana. _ _Sectio Anguli. _ _Ratio, quam habet recta composita ex Radio & Tangente 30. Grad, ad Radium ipsum. _ _Propos. 47æ. Elem. 1. Demonstratio. _ _Addita est Appendix de Mediis proportionalibus in genere. _ _KING SALOMONS POUTRAITURE OF OLD AGE_; by _John Smith_, M. D. This Treatisebeing a _Philosophical_ Discourse, though upon a _Sacred_ Theme, maycertainly claim a place among _Philosophical_ Transactions. Not here tomention the many other learned Notes, this Worthy Author gives upon thatHieroglyphical Description of Old Age, made by that Royal Pen-man of_Ecclesiastes_, cap. 12. We shall onely take notice of that surprizinglyIngenious one, there to be met with, concerning the Antiquity of theDoctrine of the _Blood's Circulation_: King _Salomon_, who lived neer 2700years agoe, using such expressions, as may, to a considering Reader, veryprobably denote the same Doctrine, which the Sagacious Dr. _Harvey_ has oflate years so happily brought to light, and introduced into all the mostIngenuous Societies of Learned men: The _Pitcher_, mention'd in the quotedplace, being Interpreted for the _Veines_, and the _Fountain_ for the_Right Ventricle of the Heart_, as the _Cistern_ for the _Left_; the_Wheele_, there spoken off, manifestly importing a _Circulation_, made bythe _Great Artery_ with its Branches, the principal Instrument thereof. * * * * * Printed with Licence for _John Martyn_, and _James Allestry_, Printers tothe Royal Society. 1666. {255} * * * * * _Num. _ 15. PHILOSOPHICAL_TRANSACTIONS. _ * * * * * _Wednesday_, _July_ 18. 1666. * * * * * The Contents. _A new Experiment, shewing, How a considerable degree of Cold may be suddenly produced without the help of _Snow_, _Ice_, _Haile_, _Wind_, or _Niter_, and that at any time of the year. An Account of two Books, lately printed in _London_; whereof the one is entituled, _EUCLIDIS ELEMENTA GEOMETRICA, novo ordine ac Methodo demonstrata_; the Author _Anonymus_. The other, _THE ENGLISH VINE-YARD VINDICATED_, by _JOHN ROSE_. _ * * * * * _A new Frigorifick Experiment shewing, how a considerable degree of _Cold_may be suddenly produced without the help of _Snow_, _Ice_, _Haile_, _Wind_, or _Niter_, and that at any time of the year. _ This subject will it self, 'tis presumed, without any other _Preamble_, speak the Cause, why this present Paper is publish't at this (unusual) timeof the Month: though, by the by, it may not be amiss to add on thisoccasion, that the Publisher of these _Tracts_ never meant so to confinehimself to a _Set_ time, as not to retain the Liberty of taking any other, when there is occasion. And there being one given him, before another Monthis come in, he does without any scruple or delay comply therewith, presenting the Curious with an Experiment which he thinks is bothseasonable, and will not be unwellcome to them; furnish't out of the AmpleMagazin of that Philosophical Benefactor, the Noble Mr. _Boyle_; Concerningwhich, thus much is further thought requisite to intimate on this occasion, that it, and some others of the same Gentlemans, that have been, and maybe, mentioned in the _Transactions_, belong to certain Treatises, theAuthor hath lying by him; but that yet he denys not {256} to communicatethem to his Friends, and to allow them to dispose thereof, upon a hope, that equitable Readers will be ready to excuse, if hereafter they shouldappear also in the Treatises they belong to, since he consents to thisAnticipation, but to comply with those, that think the imparting of realand practical Experiments, may do the Publick some Service, by exciteingand assisting mens Curiosity in the interim. As for the Experiment, you saw the other day at my Lodgings, though itbelongs to some Papers about _Cold_, that (you know) could not bePublish't, when the rest of the _History_ came forth, and therefore wasreserved for the next _Edition_ of that Book; yet the Weather having beenof late very hot, and threatning to continue so, I presume, that to giveyou here in compliance with your Curiosity an Account of the Main andPractical part of the Experiment, may enable you to gratify not onely theCurious among your Friends, but those of the Delicate, that are content topurchase a Coolness of Drinks at a somewhat chargeable rate. You may remember, that the Spring before the last, I shew'd you aparticular Account of a way, wherein by a certain substance obtain'd from_Sal Armoniack_, I could presently produce a considerable degree of _Cold_, and that with odd Circumstances, without the help of _Snow_, _Ice_, _Niter_&c. But that Experiment being difficult and costly enough, and design'd toafford men _Information_, not _Accomodations_, I afterwards tryed, whatsome more cheap and facile mixtures of likely Bodies with _Sal Armoniack_would do towards the Production of Cold, and afterwards I began toconsider, whether to that purpose alone (for my first experiment wasdesign'd to exhibite other _Phænomena_ too) those mixtures might notwithout inconvenience be omitted: and I was much confirm'd in myconjecture, by an accident, which was casually related to me by a veryIngenious Physician of my acquaintance, but not to be repeated to you infew words, though he complain'd, he knew not what to make of it. Among the several ways, by which I have made infrigidating Mixtures with_Sal Armoniack_, the most simple and facile is this; Take one pound ofpowder'd _Sal Armoniack_ and about three Pints (or pounds) of Water, putthe Salt into the Liquor, _either_ altogether, if your design be to producean intense, though {257} but a short coldness; _or_ at two, three, or fourseveral times, if you desire, that the produced coldness should rather lastsomewhat longer than be so great. Stirre the powder in the Liquor with astick or whalebone (or some other thing that will not be injur'd by thefretting Brine, that will be made) to hasten the dissolution of the Salt;upon the quickness of which depends very much the intensity of the Cold, that will ensue upon this Experiment. For the clearing up whereof, I shallannex the following particulars. [Sidenote: * _In the History of Cold. _] 1. That a considerable degree of Cold is really produced by this operation, is very evident: _First_ to the touch; _Secondly_, by this, that if youmake the Experiment (as for this reason I sometimes chuse to do) in aGlass-Body or a Tankard, you may observe, that, whilst the Solution of theSalt is making, the outside of the Metalline Vessel will, as high as themixture reaches within, be bedew'd (if I may so speak) with a multitude oflittle Drops of Water as I have * elsewhere shown that it happens, whenmixtures of Snow and Salt, being put into Glasses or other Vessels, theaqueous vapors that swim to and fro in the Air, and chance to glide alongthe sides of the Vessels, are by the coldness thereof condens'd into Water. And in our Armoniack Solution you may observe, that if you wipe off the Dewfrom any particular part of the outside of the Vessel, whilst the solutiondoes yet vigorously goe on, it will quickly collect fresh Dew, which may besometimes copious enough to run down the sides of the Vessel. But_Thirdly_, the best and surest way of finding out the Coldness of ourMixture is that, which I shew'd you by plunging into it a good seal'dWeatherglass furnish't with tincted Spirit of Wine. For the Ball of thisbeing put into our frigorifick mixture, the Crimson Liquor will nimblyenough descend much lower, than when it was kept either in the open Air, incommon Water, of the same temper with that, wherein the _Sal Armoniack_ wasput to dissolve. And if you remove the Glass out of our Mixture into commonwater, the tincted Spirit will, (as you may remember, it did) hastilyenough reascend for a pretty while, according to the greater or lessertime, that it continued in the _Armoniack_ Solution. And this has succeededwith me, when instead of removing the Mixture into _Common_ Water, Iremoved it into water newly impregnated with _Salt-peter_. {258} 2. The _Duration_ of the Cold, produc'd by this Experiment, depends uponseveral Circumstances; as _First_, upon the Season of the year, and presenttemperature of the Air; For, in Summer and Hot weather the Cold will soonerdecay and expire. _Secondly_, upon the Quantity of Salt and Water: For, ifboth these be great, the effect will be as well more lasting, as moreconsiderable. _Thirdly_, for ought I yet know, we may here add the Goodness& Fitness of the particular parcel of Salt, that is imploy'd; for, thoughit be hard to discern beforehand, which will be the more, and which theless proper; yet some trials have tempted me to suspect, that there may bea considerable disparity, as to their fitness to produce Cold, betwixtparcels of Salt, that are without scruple look't upon as Sal Armoniack: Ofwhich difference it were not perhaps very difficult to asign probablereasons from the Nature of the Ingredients of this compound Concrete, andthe wayes of preparing it. But the Duration of the Cold may be conceived todepend also. _Fourthly_, upon the Way of putting in the Salt into theWater. For, if you cast it in all at once, the Water will sooner acquire anintense degree of Coldness, but it will also the sooner return to itsformer temper; Whereas, if you desire but an inferiour degree of thatQuality, but that may last longer (which wil usually be the most convenientfor the Cooling of Drinks), then you may put in the Salt by little andlittle. For, keeping a long Weather-glass for a good while in ourimpregnated Mixture, I often purposely try'd, that, when the tincted liquorsubsided but slowly, or was at a stand, by putting in, from time to time, 2or 3. Spoonfuls of fresh Salt, and stirring the Water to quicken theDissolution, the Spirit of Wine would begin again to descend, if it were ata stand or rising, or subside much more swiftly than it did before. And ifyou would lengthen the Experiment, it may not be amiss, that part of theSal Armoniack be but grosly beaten, that it may be the longer indissolving, and consequently in Cooling the Water. Whilst there are dewydrops produced on the outside of the Vessel, 'tis a sign, that the Coldwithin continues pretty strong; for when it ceases, these drops especiallyin warm weather, will by degrees vanish. But a _surer_ way of measuring theduration of the Cold, is, by removing from time to time the Seal'dWeather-glass out of the Saline Mixture into the same common Water, withpart of which it was made. And though it be not easie to determin any thingparticularly about this matter; yet it may somewhat assist you in yourEstimates, to be inform'd, That I have in the Spring by a goodWeather-glass found a sensible adventitious Cold made by a pound of SalArmoniack at the utmost, to last about 2 or 3 hours. 3. To cool Drinks with this Mixture, you may put them in _thin_ Glasses, the thinner the better; which (their orifices being stopp'd, and still keptabove the Mixture) may be moved to and fro in it, and then be immediatelypour'd out to be drunk: Though when in the Glass, I imployed, wasconveniently shap'd as, like a Sugar-loaf, or with a long Neck, I found itnot amiss to drink it out of that, without pouring it into any other; whichcan scarce be done without lessning the Coolness. The refrigeration, if theGlass viall be convenient, is quickly perform'd: And if one have a mind tocool his hands, he may readily do it by applying them to the outside of theVessel, that contains the refrigerating Mixture; by whose help, pieces ofChrystal, or Bullet for the cooling of {259} the Mouths or Hands of thosepatients, to whom it may be allow'd, may be potently cool'd, and other suchrefreshments may be easily procur'd. 4. How far Sal Armoniack, mingl'd with Sand or Earth, and not dissolv'd, but only moistn'd with a little Water sprinkl'd on it, will keep Bottles ofWine or other liquors more coole, than the Earth or that Sand alone willdo, I have not yet had opportunity by sufficient trials fully to satisfiemy self, and therefore resign that Enquiry to the Curious. 5. For the cooling of Air, and Liquors, to adjust Weather-glasses (to beable to do which at all times of the year, was one of the chief aimes, thatmade me bethink my self of this Experiment;) or to give a small quantity ofBeer &c. A moderate degree of coolness, it will not be requisite, to employneer so much as a whole pound of Sal Armoniack at a time. For, you mayeasily observe by a seal'd Weather-glass, that a very few ounces, wellpouder'd and nimbly dissolv'd in about 4. Times the weight of Water, willserve well enough for many purposes. 6. And that you may the less, scruple at this, I shall tell you, that evenbefore and after Midsummer, I have found the Cold producible by ourExperiment to be considerable and useful for refrigerating of Drinks, &c. But if the Sal Armoniack be of the fittest sort (for I intimated above, that I suspected, 'tis not equally good) and if the season of the year domake no disadvantagious difference, the degree of Cold, that may beproduced by no more than one pound (if not by less) of Sal Armoniack, may, within its own Sphere of Activity, be much more vehement, than, I presume, you yet imagine, and may afford us excellent Standards to adjust seal'dWeather glasses by; and for several other purposes, For I remember that inthe Spring, about the end of _March_, or beginning of _April_, I was ablewith one pound of Sal Armoniack, and a requisite proportion of Water, toproduce a degree of Cold much greater, than was necessary the precedingWinter, to make it frosty Weather abroad; nay I was able to produce realIce in a space of time, almost incredibly short. To confirm whichparticulars, because they will probably seem strange to you, I will hereannex the Transcript of an entry, that I find in a Note book of the_Phænomena_ and success of one of those Experiments, as I then tryed it;though I should be asham'd to expose to your perusal a thing so rudelypen'd; if I did not hope, you would consider, that 'twas hastily writtenonely for my own Remembrance. And that you may not stop at any thing in theimmediately annext Note, or the two, that follow, it will be requisite topremise this Account of the seal'd Thermoscope; (which was a good one)wherewith these Observations were made; That the length of the Cylindricalpipe was 16. Inches; the Ball, about the bigness of a somewhat largeWalnut, and the Cavity of the Pipe by guess about an eight or ninth part ofan inch Diameter. The First Experiment is thus registered. _March_ the 27th, in the Seal'dWeather glass, when first put into the Water, the tincted Spirit rested at8-5/8 inches; being suffered to stay there a good while, and now and thenstirr'd to and fro in the Water; it descended at length a little beneath7-5/8 inches; then the _Sal Armoniack_ being put in, within about a quarterof an hour or a little more it descended to 2-11/16 inches, but before thattime, in half a {260} quarter of an hour it began manifestly to freeze thevapours and drops of water on the outside of the Glass. And when thefrigorifick power was arriv'd at the height, I several times found, thatwater, thinly plac'd on the outside, whilst the mixture within was nimblystirr'd up and down, would freeze in a quarter of a minute (by aMinute-watch. ) At about ¾ of an hour after the infrigidating Body was putin, the Thermoscope, that had been taken out a while before, and yet wasrisen but to the lowest freezing mark, being again put in the liquor, fellan inch beneath the mark. At about 2½ houres from the first Solution of theSalt I found the tincted liquor to be in the midst between the freezingmarks, whereof the one was at 5½ inches (at which height when the Tincturerested, it would usually be, some, though but a small, frost abroad;) andthe other at 4¾ inches; which was the height, to which strong and durableFrosts had reduced the liquor in the Winter. At 3 hours after the beginningof the Operation, I found not the Crimson liquor higher than the upperFreezing mark newly mention'd; after which, it continued to rise veryslowly for about an hour longer; beyond which time I had not occasion toobserve it. Thus far the _Note-book_; wherein there is mention made of a Circumstanceof some former Experiments of the like kind, which I remember was veryconspicuous in this newly recited. For, the frigorifick mixture having beenmade in a Glass body (as they call it) with a large and flattish bottom, aquantity of water, which I (purposely) spilt upon the Table, was by theoperation of the mixture within the Glass, made to freeze, and thatstrongly enough, the bottom of the Cucurbite to the Table; that stagnantliquor being turn'd into solid ice, that continued a considerable whileunthaw'd away, and was in some places about the thickness of a half Crownpiece. Another Observation, made the same Spring, but less solemn, as meantchiefly to shew the Duration of Cold in a high degree, is recorded in theseterms: The first time, the Seal'd Weather-glass was put in, before ittouch'd the common water, it stood at 8-1/8, having been left there aconsiderable while, and once or twice agitated the water, the tinctedliquor sunk but to 7-7/8, or at furthest, 7-6/8; then the frigorifickliquor being put into the water with circumstances disadvantagious enoughin (about) half a quarter of an hour the tincted liquor fell beneath 3¾, and the Thermoscope, being taken out, and then put in again, an hour afterthe water had been first infrigidated subsided beneath 5 inches, andconsequently within ¼ of an inch of the mark of the strongly freezingweather. 7. Whereas the grand thing, that is like to keep this Experiment from beingas generally _Useful_, as perhaps it will prove _Luciferous_, is theDearness of Sal Armoniack, two things may be offered to lessen thisInconvenience. For _first_, Sal Armoniack might be made much cheaper, ifinstead of fetching it beyond-sea, our Country-men made it here at home;(which it may easily be and I am ready to give you the Receipt, which is nogreat Secret. ) But _next_, I considered, that probably the infrigidatingvertue of our mixture might depend upon the peculiar Texture of the SalArmoniack whereby, whilest the Water is dissolving it, either someFrigorifick particles are extricated and excited or (rather) some particleswhich did before more agitate the minute parts of the water, are expell'd(or invited out by the ambient Bodies) or {261} come to be clogg'd in theirmotion: Whence it seem'd reasonable to expect that upon the Reunion of theSaline particles into such a Body, as they had constituted before, theredintegrated Sal Armoniack having, neer upon, the same Texture, would, upon its being redissolv'd, produce the same, or a not much inferior degreeof Coldness: And hereupon, though I well enough foresaw that an Armoniacksolution, being boyl'd up in Earthen vessels (for Glass ones are toochargeable) would, by piercing them, both lose some of the more subtleparts, and thereby somewhat impaire the texture of the rest; yet I was notdeceiv'd in Expecting, that the dry Salt, remaining in the pipkins, beingredissolv'd in a due proportion of water, would very considerablyinfrigidate it; as may further appear by the Notes, which for your greatersatisfaction you will find here subjoyn'd, as soon as I have told you, that, though for want of other vessels I was first reduc'd to make use ofEarthen ones, and the rather, because some Metallin Vessels will be injur'dby the dissolv'd Sal Armoniack, if it be boyl'd in them; yet I afterwardsfound some conveniencies in Vessels of other Mettall, as of Iron; whereofyou may command a further Account. _March_ the 29th, the Thermoscope in the Air was at 8-7/8 inches; being putinto a somewhat large evaporating glass, fill'd with water, it fell (afterit staid a pretty while, and had been agitated in the liquor) to 8. Inches:then about half the Salt, or less, that had been used _twice_ before, andfelt much less cold than the water, being put in and stirr'd about, thetincted Spirit subsided with a visible progress, till it was falnmanifestly beneath 4. Inches; and then, having caused some water to befreshly pump'd and brought in; though the newly mention'd Solution weremixt with it, yet it presently made the Spirit of Wine manifestly to ascendin the Instrument, much faster, than one would have expected, &c. And this much may suffice for this time concerning our _Frigorifick_Experiment; which I scarce doubt but the _Cartesians_ will lay hold on asvery favourable to some of their Tenents; which you will easily believe, itis _not_ to the Opinion, I have elsewhere oppos'd, of those ModernPhilosophers, that would have _Salt-petre_ to be the _Primum Frigidum_:(though I found by trial, that, whilst 'tis actually dissolving, it gives amuch considerabler degree of Cold, than otherwise. ) But about theReflexions, that may be made on this Experiment, and the Variations, andImprovements & Uses of it, though I have divers things lying by me; yet, since you have seen several of them already, and may command a sight of therest, I shall forbear the mention of them here, not thinking it proper, toswell the bulk of this Letter with them. * * * * * _An Account of two Books lately printed in London. _ I. _EUCLIDIS ELEMENTA GEOMETRICA, novo ordine ac methodo demonstrata. _ Inthis compendious and pretty Edition, the Anonymous Author pretends to haverendred these Elements more expeditious; by bringing all together into oneplace, what belongs to one and the same subject: Comprising 1. What_Euclid_ hath said of _Lines_, Streight, Intersecting one another, andParallel. 2. What he hath demonstrated of a _Single Triangle_, and of_Triangles Compared_ one with another. 3. What of the _Circle_, and itsProperties. 4. What of _Proportions_ in Triangles and other Figures. 5. What of _Quadrats_ and _Rectangles_, made of Lines diversly {262} cut. 6. What of _Plane Superficies_'s. 7. What of _Solids_. After which follow the_Problems_. The _Definitions_ are put to each _Chapter_ as need requireth. The _Axioms_, because they are few, and almost every where necessary, arenot thus distributed in _Chapters_. The _Postulata_, are not subjoyn'd tothe _Axioms_, but reserv'd for the _Problems_, the Author esteeming, thatthey being _practical_ Principles, had only place in _Problems_. This for the _Order:_ As to the _Manner_ of Demonstrating, One and the sameis observ'd in most Propositions; all with much brevity; to the end, thatwhat is not of it self difficult, may not be made so, by multitude of Wordsand Letters. II. _THE ENGLISH VINE-YARD VINDICATED. _ The Author (Mr. _John Rose_, hisMajesties Gardener at his Royal Garden in St. _James_'s) makes it hisbusiness in this small Tract (a very thin Pocket-book) by a few shortObservations made by himself, to direct _Englishmen_ in the _Choice_ of the_Fruit_, and the _Planting_ of Vine-yards; heretofore very frequentlycultivated, though of late almost quite neglected by them. He discourses skilfully, 1. Of the _severall sorts_ of _Vines_, and what_Grapes_ are most sutable to the _Climate_ of _England_; where he chieflycommends the small _Black-grape_, or _Cluster-grape_; the _Parsley-grape_;the White _Muscadine_; the _Frontiniack_; and a new _White-grape_, with ared Wood and a dark green Leaf: All these being early ripe fruit. 2. Of the_Soyle_, and _Scituation_ of a Vine-yard in _England_: Where, as to the_First_, he pitches upon a _Light Soile_, having a bottom of _Chalk_ or_Gravel_, and given to _Brambles_ observing, that no Plant whatsoever is soconnatural to the Vine for Soyl, as the _Bramble_. As for the _Scituation_he chooses that side or declivity of a Hill, that lies to the _South_ or_Southwest_; and is favoured with _other Hills_ somewhat higher, or _Woods_on the _North_ and _East_, to break the rigour of those quarters. Thisdirection he thinks of that importance, that he affirms, that thediscouragement of the Culture of Vines in _England_ has only proceeded frommen's misinformation on this material article of _Choice_ of _Soyle_ and_Scituation_. 3. How to _prepare_ the Ground for the Plantation, _vid. _ byplowing up the _Swarth_ in _July_, and by disposing the _Turf_ in _small_heaps, and so burning them, and spreading the ashes over the Land; carebeing taken, that by heaping too much materials together, the Earth be notover-burnt by the excessive heat and fire, which they require to reducethem to ashes. What is added, of the Manner of planting the _Sets_; of Dressing, Pruning, and Governing the Plantation; of the Ordering and Cultivating the Vine-yardafter the first four years, till it needs renewing; as also of the _manner_and _time_, how and when to manure the Vine-yard, with Compost, will bebetter understood from the Book it self, than can be here described; theAuthor pretending, that, those few observations of his, as the nativeproduction of his own Experience, being practised with care, the Vine-yardsin _England_ may be planted, govern'd and perpetuated with undoubtedsuccess; and offering withall to furnish those, that have a desire to renewthis Culture, and to store their grounds with _Sets_ and _Plants_ of allthose sorts, which he recommends; he having a plentiful _stock_ of themall. * * * * * Printed with Licence for _John Martyn_, and _James Allestry_, Printers tothe Royal Society. 1666. {263} * * * * * _Num. _ 16. PHILOSOPHICAL_TRANSACTIONS. _ * * * * * _Munday_, _August_ 6. 1666. * * * * * The Contents. _An essay of Dr. _John Wallis_, exhibiting his _Hypothesis_ about the _Flux and Reflux of the Sea_, taken from the consideration of the _Common Center of Gravity of the Earth and Moon_; together with an _Appendix_ of the same, containing an _Answer_ to some _Objections_, made by severall Persons against that _Hypothesis_. Some Animadversions of the same _Author_ upon Master _Hobs'_s late Book, _De Principiis & Ratiocinatione Geometrarum_. _ * * * * * _An Essay of Dr. _John Wallis_, exhibiting his _Hypothesis_ about the _Fluxand Reflux of the Sea_. _ How abstruse a subject in Philosophy, the _Flux and Reflux of the Sea_ hathproved hitherto, and how much the same hath in all Ages perplexed the Mindseven of the best of _Naturalists_, when they have attempted to render anAccount of the Cause thereof, is needless here to represent. It may perhapsbe to more purpose, to take notice, that all the deficiencies, found in the_Theories_ or _Hypotheses_, formerly invented for that End, have not beenable to deterre the Ingenious of _this_ Age from making farther search intothat Matter: Among whom that Eminent Mathematician Dr. _John Wallis_, following his happy _Genius_ for advancing reall Philosophy, hath made it apart of his later Inquiries and Studies, to contrive and deduce a certainHypothesis concerning that _Phænomenon_, taken {264} from the Considerationof the _Common Center of Gravity of the Earth and Moon_, This being byseveral Learned Men lookt upon, as a very rational Notion, it was thoughtfit to offer it by the Press to the Publick, that other Intelligent Personsalso might the more conveniently and at their leisure examine the_Conjecture_ (the Author, such is his Modesty, presenting it no otherwise)and thereupon give in their sense, and what Difficulties may occur to themabout it, that so it may be either confirm'd or laid aside accordingly; Asthe _Proposer_ himself expressly desires in the Discourse, we now, withoutany more _Preamble_, are going to subjoyn, as it was by him addressed, byway of Letter, from _Oxford_ to Mr. _Boyle, April_ 25. 1666. And afterwardscommunicated to the _R. Society_, as follows: You were earnest with me, when you last went from hence, that I would putin writing somewhat of that, which at divers times, these three or fouryears last past, I have been discoursing with your self and othersconcerning the _Common Center of Gravity of the Earth and Moon_, in orderto salving the _Phænomena_ as well of the _Seas Ebbing and Flowing_; as ofsome perplexities in _Astronomical Observations_ of the _Places_ of theCelestial Bodies. How much the World, and the great Bodies therein, are manag'd according tothe _Laws of Motion_, and _Statick Principles_, and with how much more ofclearness and satisfaction, many of the more abstruse _Phænomena_ have beensalved on such Principles, within this last Century of years, than formerlythey had been; I need not discourse to you, who are well versed in it. For, since that _Galilæo_ and (after him) _Torricellio_, and others, haveapplied _Mechanick_ Principles to the salving of _Philosophical_Difficulties; _Natural Philosophy_ is well known to have been rendered moreintelligible, and to have made a much greater progress in less than anhundred years, than before for many ages. The _Seas Ebbing and Flowing_, hath so great a connexion with the _Moons_motion, that in a manner all Philosophers (whatever other Causes they havejoyned with it), have attributed much of its cause to the _Moon_, whicheither by some _occult quality_, {265} or _particular influence_, which ithath on moyst Bodies, or by some _Magnetick vertue_, drawing the watertowards it, (which should therefore make the Water there _highest_, wherethe Moon is _vertical_) or by its gravity and pressure downwards upon theTerraqueous Globe (which would make it _lowest_ where the Moon is_vertical_) or by whatever other means (according to the severalConjectures of inquisitive persons, ) hath so great an influence on, or atleast a connexion with, the Sea's Flux and Reflux, that it would seem veryunreasonable, to seclude the consideration of the Moons motion from that ofthe Sea: The _Periods of Tides_ (to say nothing of the greatness of themnear the New moon and Full moon) so constantly waiting on the Moon'smotion, that it may be well presumed, that either the one is governed bythe other, or at least both from some common cause. But the first that I know of, who took in the consideration of the_Earth's_ motion, (_Diurnal_ and _Annual_) was _Galilæo_; who in his_Systeme of the World_, hath a particular discourse on this subject: Which, from the first time I ever read it, seemed to me so very rational, that Icould never be of other opinion, but that the true Account of this great_Phænomenon_ was to be referred to the Earths motion, as the _Principal_cause of it: Yet that of the Moon (for the reasons above mentioned) not tobe excluded, as to the determining the _Periods of Tides_, and othercircumstances concerning them. And though it be manifest enough, that_Galilæo_, as to some particulars, was mistaken in the account which therehe gives of it; yet that may be very well allowed, without any blemish toso deserving a person, or prejudice to the _main Hypothesis_: For thatDiscourse is to be looked upon onely as an _Essay_ of the _generalHypothesis_; which as to _particulars_ was to afterwards adjusted, from agood _General History of Tides_; which it's manifest enough that he hadnot; and which is in a great measure yet wanting. For were the matter ofFact well agreed on, it is not likely, that several Hypotheses should sofar differ, as that one should make the Water _then_ and _there_ at theHighest, _where_ and _when_ the other makes it at the Lowest; as when theMoon is Vertical to the place. {266} And what I say of _Galilæo_, I must in like manner desire to be understoodof what I am now ready to say to you. For I do not profess to be so wellskilled in the History of Tides, as that I will undertake presently toaccommodate my _general Hypothesis_ to the _particular cases_; or that Iwill indeed undertake for the certainty of it, but onely as an _Essay_propose it to further consideration; to stand or fall, as it shall be foundto answer matter of Fact. And truly had not your importunity (which is tome a great Command) required me to do it, I should not so easily have drawnup any thing about it, till I had first satisfied my selfe, how well theHypothesis would answer Observation: Having for divers years neglected todo it, waiting a time when I might be at leisure throughly to prosecutethis design. But there be two reasons, by which you have prevailed with me, at least todo something. _First_, because it is the common Fate of the _English_, thatout of a modesty, they forbear to publish their Discoveries, tillprosecuted to some good degree of certainty and perfection; yet are not sowary, but that they discourse of them freely enough to one another, andeven to Strangers upon occasion; whereby others, who are more hasty andventurous, comming to hear of the notion, presently publish something ofit, and would be reputed thereupon, to be the first Inventers thereof:though even that little, which they can then say of it, be perhaps muchless, and more imperfect, than what the true Authors could have publishedlong before, and what they had really made known (publikely enough, thoughnot in print) to many others. As is well known amongst us as to thebusiness of the _Lymphatick Vessels_ in _Anatomy_; the _Injection ofLiquors into the veins of Living animals_; the _Exhibiting of a straightline equal to a crooked_; the _spot in Jupiter_, whence his motion abouthis own Axis may be demonstrated; and many other the like considerableInventions. The _other_ Reason (which, with me, is more really of weight, though eventhe former be not cotemptible) is, because, as I have been already for atleast three or four years last past diverted from prosecuting the inquiryor perfecting the Hypothesis, as I had thoughts to do; so I do not know, but like Emergencies may divert me longer; and whether I shall ever so{267} do it, as to bring it to perfection, I cannot determine. Andtherefore, if as to my self any thing should _humanitus accidere_; yetpossibly the notion may prove worth the preserving to be prosecuted byothers, if I do it not. And therefore I shall, at least to your self, givesome general account of my present imperfect and undigested thoughts. I consider therefore, that in the Tides, or the Flux and Reflux of the Sea, besides extraordinary Extravagancies or Irregularities, whence greatInundations or strangly high Tides do follow, (which yet perhaps may provenot to be so meerly accidental as they have been thought to be, but mightfrom the regular Laws of Motion, if well considered, be both well accountedfor and even foretold;) There are these _three_ notorious Observations madeof the Reciprocation of Tides. _First_, the _Diurnal_ Reciprocation;whereby twice in somewhat more than 24. Hours, we have a Floud and an Ebbe;or a High-water and Low-water. _Secondly_, the _Menstrual_; whereby in one_Synodical_ period of the Moon, suppose from Full-moon to Full-moon, theTime of those Diurnal Vicissitudes doth move round through the wholecompass of the [Greek: Nuchthêmeron], or Natural day of twenty four hours:As for instance, if at the Full-moon the full Sea be at such or such aplace just at Noon, it shall be the next day (at the same place) somewhatbefore One of the clock; the day following, between One and Two; and soonward, till at the New moon it shall be at midnight; (the other Tide, which in the Full moon was at midnight, now at the New-moon coming to be atnoon;) And so forward till at the next Full-moon, the Full sea shall (atthe same place) come to be at Noon again: Again, That of the Spring-tidesand Neap-tides (as they are called;) about the Full-moon and New-moon theTides are at the Highest, at the Quadratures the Tides are at the Lowest:And at the times intermediate, proportionably. _Thirdly_, the _Annual_;whereby it is observed, that at sometimes of the year, the Spring-tides areyet much higher than the Spring-tides at other times of the year: WhichTimes are usually taken to be at the Spring and Autumne; or the twoÆquinoxes; but I have reason to believe (as well from my own Observations, for many years, as of others who have been {268} much concerned to heed it, whereof more will be said by and by;) that we should rather assign thebeginnings of _February_ and _November_, than the two _Æquinoxes_. Now in order to the giving account of these three Periods, according to the_Laws of Motion_ and _Mechanick Principles_; We shall _first_ take forgranted, what is now adayes pretty commonly entertained by those, who treatof such matters; _That a Body in motion is apt to continue its motion, andthat in the same degree of celerity, unless hindred by some contraryImpediment_; (like as a Body at rest, to continue so, unless by somesufficient mover, put into motion:) And accordingly (which daily experiencetestifies) if on a Board or Table, some loose incumbent weight, be for sometime moved, & have thereby contracted an _Impetus_ to motion at such arate; if that Board or Table chance by some external obstacle, orotherwise, to be stopped or considerably retarded in its motion, theincumbent loose Body will shoot forward upon it: And contrarywise, in casethat Board or Table chance to be accelerated or put forward with aconsiderably greater speed than before, the loose incumbent Body, (nothaving yet obtained an equal _Impetus_ with it) will be left behind, orseem to fly backward upon it. Or, (which is _Galilæo_'s instance, ) if abroad Vessel of Water, for some time evenly carried forward with the waterin it, chance to meet with a stop, or to slack its motion, the Water willdash forward and rise higher at the fore part of the Vessel: And, contrarywise, if the Vessel be suddenly put forward faster than before; theWater will dash backwards, and rise at the hinder part of the Vessel. Sothat an Acceleration or Retardation of the Vessel, which carries it, willcause a rising of the Water in one part, and a falling in another: (whichyet, by its own weight, will again be reduced to a Level as it was before. )And consequently, supposing the Sea to be but as a loose Body, carriedabout with the Earth, but not so united with it, as necessarily to receivethe same degree of _Impetus_ with it, as its fixed parts do: Theacceleration or retardation in the motion of this or that part of theEarth, will cause (more or less, according to the proportion of it) such adashing of the Water, or rising at one part, with a Falling at another, asis that, which we call the Flux and Reflux of the Sea. {269} [Illustration] Now this premised, We are next, with him, to suppose the Earth carriedabout with a double motion; The one _Annual_, as (_Fig. _ 1. ) in B E C thegreat Orb, in which the Center of the Earth B, is supposed to move aboutthe Sun A. The other _Diurnal_, whereby the whole moves upon its own _Axis_, and eachpoint in its surface describes a Circle, as D E F G. It is then manifest, that if we suppose, that the Earth moved but by anyone of these motions, and that regularly, (with an equal swiftness;) theWater, having once attained an equal _Impetus_ thereunto, would still holdequal pace with it; there being no occasion, from the Quickening orSlackening of the Earths motion, (in that part where the Water lyeth) forthe Water thereon either to be cast Forward or fall Backward; and therebyto accumulate on the other parts of the Water: But the true motion of eachpart of the Earths surface being compounded of those two motions, the_Annual_ and _Diurnal_; (the _Annual_ in B E C being, as _Galilæo_ theresupposeth, about three times as fast as a _diurnal_ motion in a greatCircle, as D E F;) while a Point in the Earths surface moves about itsCenter B. From G. To D. And E. And at the same time, its Center B. Becarried forwards to C; the true motion of that Point forwards, is made upof both those motions; to wit, of B to C, and of G to E; but while G movesby D to E, E moves backward by F to G, contrary to the motion of B to C; sothat the true motion of E, is but the difference of B C, and E G: (for, beside the motion of B above the Center; G. Is also put forward as much asfrom G to E; and E put backward as much as from E to G:) so that the_Diurnal_ motion, in that part of the Earth, which is next the Sun, as E FG, doth abate the progress of the _Annual_, (and most of all at F;) and inthe other part, which is from the Sun, as G D E, it doth increase it, (andmost of all at D. ) that is, in the day time there is abated, in the nighttime is added to the _Annual_ motion, about as much as is G E, the Earths_Diameter_. Which would afford us a Cause of two Tides in twenty fourhours; the One upon the greatest Acceleration of motion, the Other upon itsgreatest Retardation. And thus far _Galilæo_'s Discourse holds well enough; But then {270} inthis it comes short; that as it gives an Account of two Tides; so those twoTides are alwayes to be at F and D; that is, at _Noon_ and _Midnight_;whereas Experience tells us, that the Time of Tides, moves in a _monethsspace_ through all the 24. Hours. Of which he gives us no account. Forthough he do take notice of a Menstrual Period; yet he doth it onely as tothe _Quantity_ of the Tides; greater or less; not as to the _Time_ of the_Tides_, sooner or later. [Sidenote: * _Vid. Riccioli Almagest. Novum_, Tom. 1, lib. 4. Cap. 10. N. 111. Pag. 216. 2. ] To help this, there is one (_Vid. * Jo. Baptista Balianus_) who makes the_Earth_ to be but a _secondary_ Planet; and to move, not directly about theSun, but about the Moon, the Moon meanwhile moving about the Sun; in likemanner as we suppose the Earth to move about the Sun, and the Moon aboutit. But this, though it might furnish us with the foundation of a _Menstrual_Period of Accelerations and Retardations in the compound motion of severalparts of the Earths surface; yet I am not at all inclined to admit this asa _true Hypothesis_, for divers Reasons, which if not demonstrative, areyet so consonant to the general Systeme of the World, as that we have nogood ground to disbelieve them. For 1. The Earth being undeniably thegreater Body of the two (whereof there is no doubt to be made) it cannot bethought probable, that this should be carried about by the Moon, lesserthan it self: The contrary being seen, not onely in the _Sun_, which isbigger than any of the Planets, which it carryes about; but in _Jupiter_, bigger than any of his _Satellites_; and _Saturne_, bigger than his. 2. Asthe _Sun_ by it's motion about it's own Axis, is with good reason judged tobe the _Physical_ cause of the _Primary_ Planets moving about it; So thereis the like reason to believe, that _Jupiter_ and _Saturne_ moving abouttheir Axes, are the Physical cause of their _Satellites_ moving about them, which motion of _Jupiter_ hath been of late discover'd, by the help of a_fixed_ Spot discern'd in him; and we have reason to believe the like of_Saturne:_ Whether _Venus_ and _Mercury_ (about whom no _Satellites_ havebeen yet observed) be likewise so moved; we have not yet the like ground todetermine: But we have of _Mars_; from {271} the Observations of Mr. _Hook_made in _February_ and _March_ last, and by him communicated to the _RoyalSociety_, and since Printed in the _Transactions_, published _Apr. _ 2. 1666. Consonant to the like observations of _Jupiter_, made by him in_May. _ 1664, and since communicated to the same _Society_; and thenpublished in the _Transactions_, of _March. _ 6. Then next following. Nowthat the Earth hath such a motion about its own _Axis_ (whereby it might befitted to carry about the Moon) is evident by its _Diurnal_ motion. And itseems as evident that the Moon hath not; because of the same side of theMoon alwaies turned towards us; which could not be, if the Moon carried theEarth about: Unlesse we should say, that it carries about the Earth in justthe same Period, in which it turnes upon its own Axis: Which is contrary tothat of the Sun carrying about the Planets: the shortest of whose Periods, is yet longer than that of the Suns moving about its own Axis. And the likeof _Jupiter_, shorter than the Period of any of his _Satellites_; if atleast the Period of his conversion about his Axis, lately said to beobserved, prove true. (Of _Saturn_ we have not yet any Period assigned; butit's likely to be shorter, than that of his _Satelles_. ) And therefore wehave reason to believe, not that by the Moons motion about its Axis theEarth should be carried by a contemporary Period (whereby the same face ofthe Moon should be ever towards us;) but that by the Earths revolutionabout its Axis in 24. Hours, the Moon should be carried about it in about29. Dayes, without any motion on its own Axis: And accordingly, that the_Secondary_ Planets about _Jupiter_ and _Saturn_, are not (like their_Principals_) turned about their own Axis. And therefore I am not at allinclined to believe, that the _Menstrual_ Period of the Tides with us, isto be salved by such an Hypothesis. In stead of this, that _Surmise_ of mine, (for I dare not yet, withconfidence give it any better name, ) of what I have spoken to youheretofore, (and which hath occasioned this present account which I am nowgiving you, ) is to this purpose. The Earth and Moon being known to be Bodies of so great connexion (whetherby any Magnetick, or what other Tye, I will not determine; nor need I, asto this purpose;) as that {272} the motion of the one follows that of theother; (The Moon observing the Earth as the Center of its _periodick_motion:) may well enough be looked upon as _one Body_, or rather _oneAggregate of Bodies_, which have _one common center of Gravity_; whichCenter (according to the known Laws of _Staticks_) is in a streight Lineconnecting their respective Centers, so divided as that its parts be inreciprocal proportion to the Gravities of the two Bodies. As for Example;Suppose the Magnitude (and therefore probably, the Gravity) of the Moon tobe about an _One and fourtieth part_ of that of the Earth; (and thereabouts_Hevelius_ in his _Selenography_ page 203. Doth out of _Tycho_, estimatethe proportion; and an exact certainty is not necessary to our presentbusinesse. ) And the distance of the Moons Center from the Center of theEarth, to be about _fifty six Semidiameters_ of the Earth, (as thereaboutshe doth there estimate it, in its middle distance; and we need not be nowvery accurate in determining the numbers; wherein Astronomers are not yetvery well agreed. ) The distance of the Common Center of Gravity of the twoBodies, will be from that of the Earth, about a two and fourtieth part offifty six Semidiameters; that is, about 56/42 or 4/3 of a Semidiameter;that is about 1/3 of a Semidiameter of the Earth, above its surface, in theAir, directly between the Earth and Moon. Now supposing the Earth and Moon, joyntly as one Body, carried about by theSun in the great Orb of the _Annual_ motion; this motion is to beestimated, (according to the Laws of _Staticks_, in other cases, ) by themotion of the common Center of Gravity of both Bodies. For we use in_Staticks_, to estimate a Body, or Aggregate of Bodies, to be movedupwards, downwards, or otherwise, so much as its Common Center of Gravityis so moved, howsoever the parts may change places amongst themselves. And accordingly, the Line of the _Annual_ motion, (whether _Circular_ or_Elliptical_; of which I am not here to dispute, ) will be described, not bythe Center of the Earth (as we commonly estimate it, making the Earth aPrimary and the Moon a Secondary Planet, ) nor by the Center of the Moon, (as they would do, who make the Moon the Primary and the Earth a {273}Secondary Planet, against which we were before disputing:) But by the_Common Center of Gravity of the Bodies, Earth and Moon_, as one Aggregate. [Sidenote: See Fig. 2. And 3. ] Now supposing A B C D E to be a part of the great Orb of the _Annual_motion, described by the Common Center of Gravity, in so long time as froma _Full-Moon_ at A to the next _New-Moon_ at E; (which, though an Arch of a_Circle_ or _Ellipse_, whose Center we suppose at a due distance below it;yet being put about 1/25 of the whole, may well enough be here representedby a streight Line:) the Center of the Earth at T, and that of the Moon atL, must each of them (supposing their common Center of Gravity to keep theLine A E) be supposed to describe a _Periphery_ about that Common Center, as the Moon describes her Line of _Menstrual_ motion (Of which I have (inthe _Scheme_) onely drawn that of the _Earth_; as being sufficient to ourpresent purpose; parallel to which, if need be, we may suppose onedescribed by the Moon; whose distance is also to be supposed much greaterfrom T than in the _figure_ is expressed, or was necessary to expresse. )And in like manner E F G H I, from that _New moon_ at E, to the next_Full-moon_ at I. [Illustration] From A to E (from Full moon to New moon, ) T moves (in its own _Epicycle_)upwards from the Sun: And from E to I, (from New moon to Full moon) itmoves downwards, toward the Sun. Again, from C to G, (from last quarter tothe following first quarter, ) it moves _forwards according_ to the _Annual_motion; But from G forward to C, (from the first Quarter to the ensuinglast Quarter, ) it moves _contrary_ to the _Annual_ motion. It is manifest therefore, according to this Hypothesis, that from Lastquarter to First quarter (from C to G, while T is above the Line of the_Annual_ motion) its _Menstrual_ motion in its Epicycle _adds_ somewhat ofAcceleration to the _Annual_ motion, and most of all at E, the New-moon:And from the first to the last quarter (from G forward to C, while T isbelow the Line of the _Annual_ motion, ) it _abates_ of the _Annual_ motion;and most of all at I, or A the Full-moon. So that in pursuance of _Galilæo's_ Notion, the _Menstrual_ {274} adding toor detracting from the _Annual_ motion, should either leave behinde, orcast forward, the loose waters incumbent on the Earth, (and thereby cause aTide, or accumulation of Waters) and most of all at the Full Moon andNew-moon, where those Accelerations or Retardations are greatest. Now this _Menstrual_ motion, if nothing else were superadded to the_Annual_, would give us two Tides in a moneth, and no more; (the one uponthe Acceleration, the other on the Retardation;) at New moon and Full-moon;and two Ebbs, at the two Quarters; and in the Intervals, Rising and Fallingwater. But the _Diurnal_ motion superadded, doth the same to this _Menstrual_, which _Galilæo_ supposeth it to do to the _Annual_; that is, doth _Add_ to, or _Subtract_ from, the _Menstrual_ Acceleration or Retardation; and sogives us Tide upon Tide. [Illustration] For in whatsoever part of its Epicycle, we suppose T to be; yet because, while by its _Menstrual_ motion the Center moves in the Circle L T N; eachpoint in its surface, by its diurnal motion moves in the Circle L M N:whatever effect (accelerative or tardative) the _Menstrual_ would give, that effect by the _Diurnal_ is increased in the parts L M N (or rather l Mn. The Semicircle) and most of all at M: but diminished in the parts N O L(or rather n O l) and most of all at O. So that at M, and O, (that is whenthe Moon is in the _Meridian_ below or above the _Horizon_, ) we are to havethe Diurnal Tide or High-water, occasioned by the greatest Acceleration orRetardation, which the _Diurnal_ Arch gives to that of the _Menstrual_:which seems to be the true cause of the _Daily Tides_. And withall gives anaccount, not onely why it should be _every_ day; but like wise, why at_such a time_ of the day; and why this time should in a moneth run throughthe whole 24 hours; _viz. _ because the Moons coming to the _Meridian_ aboveand below the _Horizon_, (or as the Seamen call it, the _Moons Southing_, and _Northing_, ) doth so: As likewise of the _Spring tides_ and_Neap-tides_. For, when it so happens, that the _Menstrual_ and _Diurnal_Accelerations or Retardations, be coincident, (as at New moons andFull-moons they are, ) the effect must needs be the greater. And although(which is not to be dissembled) this happen {275} but to one of the twoTides; that is, the Night-tide at the New-moon (when both motions do mostof all Accelerate, ) and the Day-tide at Full-moon (when both do most Retardthe _Annual_ motion;) Yet, this tide being thus raised by two concurrentcauses; though the next Tide have not the same cause also, the _Impetus_contracted will have influence upon the next Tide; Upon a like reason, as a_Pendulum_ let fall from a higher Arch, will (though there be no new causeto occasion it) make the Vibration on the other side (beyond thePerpendicular) to be also greater: Or, of water in a broad Vessel, if it beso jogged, as to be cast forward to a good height above its Levell, willupon its recoyling, by its own gravity, (without any additional cause)mount so much the higher on the hinder part. But here also we are to take notice, that though all parts of the Earth byits _Diurnal_ motion do turn about its Axis, and describe _parallel_Circles; yet not _equal_ Circles; but _greater_ neer the _Æquinoctial_, and_lesser_ near the _Poles_, which may be a cause why the Tides in some partsmay be much greater than in others. But this belongs to the _particular_considerations, (of which we are not now giving an Account:) not to the_general_ Hypothesis. Having thus endeavoured to give an account of the _Diurnal_ and _Menstrual_Periods of Tides; It remains that I endeavour the like as to the _Annual_. Of which there is, at least, thus much agreed; That, at some times of theyear, the Tides are noted to be much higher, than at other times. But here I have a double task; _First_, to rectify the Observation; and_then_, to give an account of it. As to the _First_; It having been observed (grosly) that those high Tideshave used to happen about the _Spring_ and _Autumn_; it hath been generallytaken for granted (without any more nice observation) that the _twoÆquinoxes_ are the proper times, to which these _Annual high Tides_ are tobe referred; And such causes sought for, as might best sute with such aSupposition. But it is now, the best part of twenty years, since I have had frequentoccasions to converse with some Inhabitants of _Rumney-marsh_ in _Kent_;where the Sea being kept out with great Earthen walls, that it do not athigh water overflow the Levell; {276} and the Inhabitants livelyhooddepending most on grazing, or feeding Sheep; they are (as you may believethey have reason to be) very vigilant and observant, at what times they aremost in danger of having their Lands drowned. And I find them generallyagreed, by their constant Observations, (and Experience dearly bought) thattheir times of danger are about the beginning of _February_ and of_November_; that is, at those Spring Tides which happen near those times;to which they give the names of _Candlemass-stream_ and_Allhallond-stream_; And if they scape those Spring-tides, they apprehendthemselves out of Danger for the rest of the year. And as for _March_ and_September_ (the two _Æquinoxes_) they are as little solicitous of them, asof any other part of the year. This, I confess, I much wondred at, when I first heard it; and suspected itto be but a mistake of him, that first told me, though he were indeed aperson not likely so to be mistaken, in a thing wherein he was so muchconcerned: But I soon found, that it was not onely his, but a generalobservation of others too; both there, and elsewhere along the Sea coast. And though they did not pretend to know any reason of it, (nor so much asto enquire after it;) Yet none made doubt of it; but would rather laugh atany that should talk of _March_ and _September_, as being the dangeroustimes. And since that time, I have my self very frequently observed (bothat _London_ and elsewhere, as I have had occasion), that in those months of_February_ and _November, _ (especially _November_), the Tides have run muchhigher, than at other times: Though I confess, I have not been so diligentto set down those Observations, as I should have done. Yet this I doparticularly very well remember, that in _November_ 1660. (the same yearthat his Majesty returned) having occasion to go by Coach from the _Strand_to _Westminster_, I found the Water so high in the middle of _King-street_, that it came up, not onely to the Boots, but into the Body of the Coach;and the _Pallace-yard_ (all save a little place near the _West-End_)overflow'd; as likewise the Market-place; and many other places; and theirCellars generally filled up with Water. And in _November_ last, 1665. Itmay yet be very well remembred, what very high Tides there were, not onelyon the Coasts of _England_, (where much hurt was {277} done by it) but muchmore, in _Holland_, where by reason of those Inundations, many Villages andTowns were overflow'd. And though I cannot so particularly name otheryears, yet I can very safely say, that I very often observed Tidesstrangely high about those times of the year. This Observation did for divers years cause me much to wonder, not onlybecause it is so contrary to the received opinion of the two _Æquinoxes_;but because I could not think of any thing signal at those times of theyear: as being neither the two _Æquinoxes_, nor the two _Solstices_, northe Sun's _Apogæum_ and _Perigæum_: (or Earths _Aphelium_ and_Perihelium_;) nor indeed, at contrary times of the year, which at least, would seem to be expected. From _Alhollandtide_ to _Candlemass_ being butthree months; and from thence to _Alhollandtide_ again nine months. At length it came into my mind, about four years since, that though theredo not about these times happen any _single_ signal Accident, which mightcast it on these times, yet there is a _compound of two_ that may do it;Which is the _Inequality_ of the _Natural day_ (I mean that of 24. Hours, from noon to noon) arising at least from a double cause; either of whichsingly would cast it upon other times, but both joyntly on those. It's commonly thought, how unequal soever the length be of the _Artificial_dayes as contradistinguished to nights, yet that the _Natural_ Days, reckoning from noon to noon, are all _equal_: But _Astronomers_ know well, that even these dayes are _unequal_. For, this _Natural_ Day is measured _not onely_ by one intire conversion ofthe _Æquinoctial_, or 24. _Æquinoctial_ hours, (which is indeed taken to beperformed in equal times, ) _but_ increases by so much, as answers to thatpart of the _Sun's_ (or _Earths_, ) Annual motion as is performed in thattime. For, when that part of the _Æquinoctial_, which (with the _Sun_) wasthe _Meridian_ yesterday at noon, is come thither again to day, it is notyet _Noon_ (because the Sun is not now at the place where yesterday he was, but is gone forward about one degree, more or less) but we must stay tillthat place, where the _Sun_ now is, comes to the _Meridian_ before it benow _Noon_. Now this Additament (above the 24 _Æquinoctial_ hours, or intire conversionof the _Æquinoctial_) is upon a double account {278} unequal. _First_, because the Sun, by reason of its _Apogæum_ and _Perigæum_, doth not at alltimes of the year dispatch in one day an equal Arch of the _Ecliptick_; butgreater Arches neer the _Perigæum_, which is about the middle of_December_; and lesser neer the _Apogæum_, which is about the middle of_June_: As will appear sufficiently by the _Tables_ of the Sun's Annualmotion. _Secondly_, though the Sun should in the _Ecliptick_ move alwaiesat the same rate; yet equal Arches of the _Ecliptick_ do not in all partsof the _Zodiack_ answer to equal Arches of the _Æquinoctial_, by which weare to estimate time: Because some parts of it, as about the two_Solsticial_ Points, lie nearer to a _parallel_ position to the_Æquinoctial_, than others, as those about the two _Æquinoctial_ points, where the _Ecliptick_ and _Æquinoctial_ do intersect; whereupon an Arch ofthe _Ecliptick_, neer the _Solsticial_ points answers to a greater Arch ofthe _Æquinoctial_, than an Arch equal thereunto neer the _Æquinoctial_points: As doth sufficiently appear by the _Tables_ of the Suns _rightAscension_. According to the _first_ of these causes, we should have the longest_natural_ daies in _December_, and the shortest in _June_, which if it didoperate alone, would give us at those times two _Annual_ High-waters. According to the _second_ cause, if operating singly, we should have thelongest daies at the two Solstices in _June_ and _December_, and the twoshortest at the _Æquinoxes_ in _March_ and _September_; which would atthose times give occasion of four _Annual_ High-waters. But the true _Inequality_ of the Natural Days, arising from a _Complicationof those two causes_, sometimes crossing and sometimes promoting each eachother: though we should find some increases or decreases of the _Natural_daies at all those seasons answerable to the respective causes (and perhapsof Tides proportionably thereunto:) yet the longest and shortest _naturaldaies_ absolutely of the whole year (arising from this complication ofCauses) are about those times of _Allhallontide_ and _Candlemas_; (or notfar from them) about which those _Annual_ High-tides are found to be: Aswill appear by the _Tables of Æquation_ of _Natural_ daies. And therefore Ithink, we may with very good reason cast this _Annual_ Period upon thatcause, or rather {279} complication of causes. For (as we before shewed inthe _Menstrual_ and _Diurnal_) there will, by this inequality of Naturaldaies, arise a _Physical_ Acceleration and Retardation of the Earths _Mean_motion, and accordingly a casting of the Waters backward or forward; eitherof which, will cause an Accumulation or High-water. 'Tis true, that these longest and shortest daies, do (according to the_Tables_, some at least) fall rather before, than after _Alhallontide_ and_Candlemas_ (to wit the ends of _October_ and _January_;) but so do also(sometimes) those high Tydes: And it is not yet so well agreed amongst_Astronomers_, what are all the Causes (and in what degrees) of theInequality of Natural daies; but that there be diversities among them, about the true time: And whether the introducing of this New Motion of theEarth in its _Epicycle_ about this Common Center of _Gravity_, ought nottherein also to be accounted for, I will not now determine: Having alreadysaid enough, if not too much, for the explaining of this generalHypothesis, leaving the particularities of it to be adjusted according tothe true measures of the motions; if the General Hypothesis be found fit tobe admitted. Yet this I must add, (that I be not mistaken) that whereas I cast the timeof the daily Tydes to be at all places, when the Moon is there in the_Meridian_; it must be understood of _open_ Seas, where the water hath suchfree scope for its motions, as if the whole Globe of Earth were equallycovered with water: Well knowing, that in _Bayes_ and _In land-Channels_, the position of the Banks and other like causes must needs make the timesto be much different from what we suppose in the open Seas: And likewise, that even in the Open Seas, _Islands_, and _Currents_, _Gulfs_ and_Shallows_, may have some influence, though not comparable to that of_Bays_ and _Channels_. And moreover, though I think, that Seamen docommonly reckon the time of High-water in the _Open Seas_, to be then, whenthe Moon is there in the _Meridian_ (as this Hypothesis would cast it:) YetI do not take my self to be so well furnished with a _History of Tides_, asto assure my self of it; much less to accommodate it to particular placesand cases. Having thus dispatched the main of what I had to say {280} concerning theSeas Ebbing and Flowing: Had I not been already too tedious, I should nowproceed to give a further reason, why I do introduce this consideration ofthe _Common Center of Gravity_ in reference to _Astronomical Accounts_. Forindeed, that which may possibly seem at first to be an Objection _against_it, is with me one reason _for_ it. It may be thought perhaps, that if the Earth should thus describe an_Epicycle_ about the Common Center of Gravity, it would (by this its changeof place) disturbe the _Cælestial_ motions; and make the _apparent_ placesof the Planets, especially some of them, different from what they wouldotherwise be. For though so small a removal of the Earth, as the _Epicycle_would cause (especially if its _Semidiameter_ should not be above 1-1/3 ofthe Earths Semidiameter) would scarce be sensible (if at all) to theremoter Planets; yet as to the nearer it might. Now though what _Galilæo_ answers to a like Objection in his _Hypothesis_;(that its possible there may be some small difference, which _Astronomers_have not yet been so accurate, as to observe) might here perhaps serve theturn; Yet my answer is much otherwise; to wit, that such difference hathbeen observed and hath very much puzzeled _Astronomers_ to give an accountof. About which you will find Mr. _Horrocks_ (in some of his Letters, whereof I did formerly, upon the Command of the _Royal Society_, make an_Extract_) was very much perplexed; and was fain, for want of other relief, to have recourse to somewhat like _Keplers_ amicable _Fibres_, which didaccording to the several positions of the Moon, accelerate or retard theMoon's motion; which _amicable Fibres_ he had no affection to at all (asthere appears) if he could any other waies give account of those littleinequalities; and would much rather (I doubt not) have embraced this Notionof the Common Center of Gravity, to salve the _Phænomenon_, had it come tohis mind, or been suggested to him. And you find, that other _Astronomers_have been seen to bring in (some upon one supposition, some upon another)some kind of _Menstrual Æquation_, to solve the inequalities of the Moon'smotion, according to her _Synodical_ Revolution, or different Aspects (ofNew-moon, Full Moon, &c. ) beside what concerns her own _Periodical_ motion. {281} For which, this consideration of the _Common Center of Gravity of the Earthand Moon_, is so proper a remedy (especially if it shall be found preciselyto answer those _Phænomena_, which I have not Examined, but am very apt tobelieve) that it is so far from being, with me, an Objection against it, that it is one of the reasons, which make me inclinable to introduce it. I must before I leave this, add one Consideration more, That if we shallupon these Considerations think it reasonable, thus to consider the _CommonCenter of Gravity of the Earth and Moon_; it may as well be thoughtreasonable, that the like Consideration should be had of _Jupiter_ and hisfour _Satellites_, which according to the Complication of their severalmotions, will somewhat change the position of _Jupiter_, as to that _Commoncenter of Gravity_ of all these Bodies; which yet, because of theirsmallness, may chance to be so little, as that, at this distance, thechange of his apparent place may not be discernable. And what is said of_Jupiter_, is in the like manner to be understood of _Saturne_ and his_Satelles_, discovered by _Hugenius_: For all these _Satellites_ are totheir _Principals_, as so many Moons to the Earth. And I do very wellremember, in the Letters forecited, Mr. _Horrocks_ expresseth some suchlittle inequalities in _Saturnes_ motion, of which he could not imaginewhat account to give, as if (to use his Expression) this crabbed _OldSaturn_ had despised his _Youth_. Which, for ought I know, might wellenough have been accounted for, if at that time the _Satelles_ of _Saturn_had been discovered, and that Mr. _Horrocks_ had thought of such a notionas the _Common Center of Gravity_ of _Saturn_ and his _Companion_, to beconsiderable, as to the guiding of his motion. You have now, in obedience to your Commands, an Account of my thoughts, asto this matter, though yet immature and unpolished: What use you willplease to make of them, I shall leave to your prudence, &c. * * * * * _An _APPENDIX_, written by way of Letter to the _Publisher_; Being ananswer to some Objections, made by several Persons, to the precedentDiscourse. _ I Received yours; and am very well contented, that _objections_ be madeagainst my _Hypothesis_ concerning _Tydes_: being {282} proposed but as aconjecture to be examined; and, upon that Examination, rectified, if therebe occasion; or rejected, if it will not hold water. 1. To the first objection of those you mention; _That it appears not howtwo Bodies, that have no tye, can have one common Center of Gravity:_ thatis (for so I understand the intendment of the objection) can act or beacted in the same manner, as if they were connected: I shall onely answer, that it is harder to shew _How_ they have, than _That_ they have it. Thatthe Load-stone and Iron have somewhat equivalent to a Tye; though we see itnot, yet by the effects we know. And it would be easy to shew, that twoLoad-stones, at once applyed, in different positions, to the same Needle, at some convenient distance, will draw it, not to point directly to eitherof them, but to some point between both; which point is, as to those two, the _common Center of Attraction;_ and it is the same, as if some _one_Load-stone were in that point. Yet have these two Load stones no connectionor tye, though a _Common Center of Virtue_ according to which they joyntlyact. And as to the present case, _How_ the Earth and Moon are connected; Iwill not now undertake to shew (nor is it necessary to my purpose;) but, That there is somewhat, that doth connect them, (as much as what connectsthe Load-stone, and the Iron, which it draws, ) is past doubt to those, whoallow them to be carryed about by the Sun, as one Aggregate or Body, whoseparts keep a respective position to one another: Like as _Jupiter_ with his_four Satellites_, and _Saturn_ with his _one_. Some Tye there is, thatmakes those _Satellites_ attend their _Lords_, and move in a Body; thoughwe do not _See_ that Tye; nor _Hear_ the Words of Command. And so here. 2. To the second objection; _That, at Chatham and in the Thames, the AnnualSpring-tydes, happen about the Æquinoxes; not (as this Hypothesis dothsuppose elsewhere to have been observed) about the beginning of Februaryand November. _ If their meaning be, that Annual High Tydes, do then happen, and then onely: If this prove true, it will ease me of half my work. For itis then easily answered, that it depends upon the _Obliquity of theZodiack_; the parts of the Æquinoctial answering to equal parts of the{283} _Zodiack_, being neer the Solstitial points greatest, and near theÆquinoctial points least of all. But beside this _Annual Vicissitude of theÆquinoxes_, not to say, of the 4. Cardinal Points (which my Hypothesis dothallow and assert;) I believe it will be found, that there is _anotherAnnual vicissitude_ answering to the Suns _Apogæum_ and _Perigæum_. Andthat the greatest Tydes of all, will be found to be upon a result of thesetwo causes Cooperating: which (as doth the Inequality of Natural dayes, depending on these same causes) will light nearer the times, I mention. Towhat is said to be observed at _Chatham_ and in the _Thames_, contrary tothat I allege as observed in _Rumney marsh_: I must at present [Greek:apechein], and refer to a _melius inquirendum_. If those who object thiscontrary observation, shall, after this notice, find, upon new Observationsheedfully taken, that the _Spring-tydes_ in _February_ and _November_, arenot so high, as those in _March_ and _September_; I shall then think theobjection very considerable. But I do very well remember, that I have seenin _November_, very high Tydes at _London_, as well as in _Rumney Marsh_. And, the time is not yet so far past, but that it may be remembered (byyour self or others then in _London_) whether in _November_ last when theTydes were so high at _Dover_, at _Deal_, at _Margate_, and all along theCoast from thence to _Rumney Marsh_, as to do in some of those places muchhurt, (and, in _Holland_, much more;) whether, I say, there were not alsoat the same time, at _London_, (upon the _Thames_) very high Tydes. But agood _Diary_ of the Height and time both of High-water, and Low-water, fora year or two together, even at _Chatham_, or _Greenwich_; but rather atsome place in the _open_ Sea, or at the _Lands end_ in _Cornwal_, or on the_West parts of Ireland_; or at St. _Hellens_, or the _Bermodas_, &c. Woulddo more to the resolving of this point, than any verbal discourse withoutit. 3. To the third Objection, _That supposing the Earth and Moon to move abouta Common center of gravity; if that the highest Tydes be at the New-moon, when the moon being nearest to the Sun, the Earth is farthest from it, andits compound motion at the swiftest; and that the Tydes abate as the Earthapproacheth nearer; till it comes into the supposed Circle of her Annualmotion: It may be demanded, why do they not still abate as the Earth comesyet nearer to the Sun; and the_ {284} _swiftnesse of its compound motionstill slackens? And so, why have we not Spring tides at the New Moon (whenthe motion is swiftest) and Neap tides at Full Moon (when the motion isslowest) but Spring tides at both?_ The answer (if observed) is alreadygiven in my _Hypothesis_ it self. Because the effect is indifferently tofollow, either upon a suddain Acceleration, or a suddain Retardation. (Likeas a loose thing, lying on a moving body; if the body be thrust suddainlyforward, that loose thing is cast back, or rather left behind, not havingyet obtained an equal _impetus_ with that of the body, on which it lyes;but if stopped, or notably retarded, that loose incumbent is thrownforward, by its formerly contracted _impetus_ not yet qualified oraccomodated to the slowness of the Body, on which it lyes. ) Now both ofthese happening, the one at the New Moon, the other at the Full Moon, docause high Tides at both. 4. To the fourth Objection, _That the highest Tydes are not at all places, about the New Moon and Full Moon; and particularly, that, in some places ofthe East Indies, the Highest Tydes are at the Quadratures_: I must firstanswer in _general_; That as to the particular varieties of Tydes inseveral parts of the World, I cannot pretend to give a satisfactoryaccount, for want of a competent History of Tydes, &c. Because (as isintimated in what I wrote in the _general_) the various positions ofChanels, Bays, Promontories, Gulfs, Shallows, Currents, Trade-winds, &c. Must needs make an innumerable variety of Accidents in particular places, of which no satisfactory account is to be given from the general_Hypothesis_ (though never so true) without a due consideration of allthose. Which is a task too great for me to undertake, being so illfurnished with materials for it. And then as to the particular instance ofsome places in the _East Indies_, where the highest Tydes are at the_Quadratures_: I suppose, it may be chiefly intended of those about_Cambaia_, and _Pegu_. At which places, beside that they are situate at theinmost parts of Vast Bayes, or Gulfs (as they are called) they have alsovast In-draughts of some hundred Miles within Land; which when the Tydesare out, do lye (in a manner) quite dry: And may therefore very well besupposed to participate the effect of the Menstrual Tydes many dayes afterthe {285} cause of them happens in the open Sea, upon a like ground as inStraights and narrow Channels the Diurnall Tydes happen some hours laterthan in the Ocean. And a like account must be given of particular accidentsin other places, from the particular situation of those places, as _Bays_, _Chanels_, _Currents_, &c. 5. To the 5. Objection, _That the Spring-Tydes happen not, with us, just atthe Full and Change, but two or three daies after_. I should with the moreconfidence attempt an Answer, were I certain, whether it be so in the_Open_ Seas, or onely in our Channels. For the Answers will not be the samein both cases. If onely in our Channels, where the Tydes find a largein-draught; but not in the Open Seas: we must seek the reason of it fromthe particular position of these places. But if it be so generally in thewide Open Seas: We must then seek a reason of it from the generalHypothesis. And, till I know the matter of Fact, I know not well, which tooffer at; lest whilst I attempt to salve one, I should fall foul of theother. I know that Marriners use to speak of Spring-Tydes at the New andFull of the Moon; though I have still had a suspition that it might be somedaies after, as well in the open Seas, as in our narrower Channels; (andtherefore I have chosen to say, in my Papers, _About_ the New and Full, rather than _At_ the New and Full; and even when I do say _At_, I intend itin that laxer sense in which I suppose the Marriners are to be understood, for _Neer_ that time:) Of which suspition you will find some intimationseven in my first Papers: But this though I can admit; yet, because I wasnot sure of it, I durst not build upon it. The truth is, the Flux andReflux of water in a vessel, by reason of the jogging of it, though itfollow thereupon; yet is, for the most part, discernable some time after. For there must, upon that jog, be some time for Motion, before theAccumulation can have made a Tyde. And so I do not know but that we mustallow it in all the Periods. For as the _menstrual_ High Tyde, is not (atleast with us) till some Daies after the Full and Change; so is the_Diurnal_ High water, about as many Hours, after the Moons comming toSouth; (I mean, At Sea: for in Chanels it varies to all Hours, according asthey are neerer or further from the open Sea:) And the _Annual_ High-Tydesof _November_ and _February_; somewhat later than {286} (what I conjectureto be from the same causes) the greatest Inequalities of the natural Days, happening in _January_ and _October_. But this though I can admit, yet(till I am sure of the matter of Fact) I do not build upon. And since ithath hitherto been the custome to speak with that laxness of expression;assigning the times of New-moon, Full-moon, and Quadratures, with the Moonscomming to South, for, what is neer those times: I did not think myselfobliged in my conjectural Hypothesis (while it is yet but a _Candidate_) tospeak more nicely. If the Hypothesis for the maine of it be found Rational;the Niceties of it are to be adjusted, in time, from particularObservation. Having thus given you some Answers to the Objections you signifie to havebeen made by several persons to my Hypothesis, and that in the same orderyour Paper presents them to me; I shall next give you some account of thetwo _Books_, which you advised me to consult; so far as seems necessary tothis business; Which, upon your intimation, I have since perused, thoughbefore I had not. And first, as to that of _Isaac Vossius, De motu Marium & Ventorum_; ThoughI do not concur with him in his Hypothesis; That all the _Great motions ofthe Seas_, &c. Should arise onely from _so small a warming of the water_ asto raise it (where most of all) _not a Foot_ in perpendicular, (as in his12_th_ Chapter. ) Or that there is no other connexion between the Moonsmotion, and the Tydes _menstrual_ period, than a _casual Synchronism_(which seems to be the doctrine of his 16_th_ and 18_th_ Chapters;) Besidemany other things in his Philosophy, which I cannot allow: Yet I am wellenough pleased with what is Historical in it, of the matter of Fact:Especially if I may be secure, that he is therein accurate and candid, notwresting the _Phænomena_ to his own purpose. But I find nothing in it, which doth induce me to vary from my Hypothesis. For, granting hisHistoricals to be all true; the account of the constant Current of the SeaWestward, and of the constant Eastern Blasts, &c. Within the _Tropicks_, ismuch more plausibly, and (I suppose) truly rendered by _Galilæo_ longsince, from the Earths _Diurnal_ motion: (which, neare the _Æquator_, describing a greater Circle, than nearer the {287} _Poles_, makes theCurrent to be there more conspicuous and swift, and consequently, the Eddy, or recurrent motion, nearer the Poles, where this is, more remiss:) thancan easily be rendered by so small a Tumor, as he supposeth. Not to adde;that his account of the Progressive motion, which he fansieth to followupon this Tumefaction, and by Acceleration to grow to so great a heightnear the Shoar (as in Chap. 13. And 14. ) is a Notion, which seems to me tooextravagant to be salved by any laws of _Staticks_. And that of the Moonsmotion onely Synchronizing with the Tydes, casually, without any _Physical_connexion; I can very hardly assent to. For it can hardly be imagined, thatany such constant _Synchronisme_ should be in Nature; but where, either theone is the cause of the other, or both depend upon some _Common_ cause. Andwhere we see so fair a foundation for a _Physical_ connection. I am notprone to ascribe it to an Independent Sychronism. In sum; His History dothwell enough agree with my Hypothesis; and I think, the Phænomena are muchbetter salved by mine, than his. And then as to _Gassendus_, in his discourse _De Æstu Maris_; I find him, after the relating of many other Opinions concerning the Cause of it, inclining to that of _Galilæo_, ascribing it to the Acceleration &Retardation of the Earths motion, compounded of the Annual and Diurnal; Andmoreover attempting to give an account of the _Menstrual Periods_ from theEarths carrying the Moon about it self, as _Jupiter_ doth his _Satellites_;which together with them is carryed about by the _Sun_, as one Aggregate;(and that the Earth with its Moon is to be supposed in like manner to becarried about by the Sun, as one Aggregate, cannot be reasonably doubted, by those who entertain the _Copernican Hypothesis_, and do allow the sameof _Jupiter_ and his _Satellites_. ) But though he would thus have the Earthand Moon looked upon as two parts of the same moved Aggregate, yet he dothstill suppose (as _Galilæo_ had done before him) that the line of the MeanMotion of this Aggregate (or, as he calls, _motus æquabilis et velutimedius_) is described by the _Center_ of the _Earth_ (about which Center hesupposeth both its own revolution to be made, and an Epicycle described bythe Moons motion;) not by another Point, distinct from the Centers of both, about which, as the {288} common Center of Gravity, as well that of theEarth, as that of the Moon, are to describe several Epicycles. And, forthat Reason fails of giving any clear account of this _Menstrual_ Period. (And in like manner, he proposeth the Consideration as well of the Earths_Aphelium_ and _Perihelium_ as of the _Æquinoctial_ and _Solstitial_Points, in order to the finding a Reason of the _Annual_ Vicissitudes; butdoth not fix upon any thing, in which himself can Acquiesce: And thereforeleaves it _in medio_ as he found it. ) It had been more agreeable to the Laws of _Staticks_, if he had, (as I do, )so considered the _Earth_ and _Moon_ as two parts of the same movable, (notso, as he doth, _aliam in Centro et sequentem præcise revolutionem axis, aliam remotius ac velut in circumferentia_, but, ) so, as to make neither ofthem the Center, but both out of it, describing Epicycles about it: Likeas, when a long stick thrown in the Air, whose one end is heavyer than theother, is whirled about, so as that the End, which did first fly foremost, becomes hindmost; the proper line of motion of this whole Body is not that, which is described by either End, but that, which is described by a middlepoint between them; about which point each end, in whirling, describes anEpicycle. And indeed, in the present case, it is not the Epicycle describedby the Moon, but that, described by the Earth, which gives the _Menstrual_Vicissitudes of motion to the Water; which would, as to this, be the same, if the Earth so move, whether there were any Moon to move or not; nor wouldthe Moons Motion, supposing the Earth to hold on its own course, any whitconcern the motion of the Water. [Illustration] But now, (after all our Physical, or Statical Considerations) the clearestEvidence for this Hypothesis (if it can be had) will be from CelestialObservations. As for instance; (see _Fig. _ 5. ) Supposing the Sun at S; theEarths place in its Annual Orb at T; and _Mars_ (in opposition to the Sun, or near it) at M: From whence _Mars_ should appear in the Zodiack at[gamma], and will at Full moon be seen there to be; the Moon being at C andthe Earth at c; (and the like at the New-moon. ) But if the Moon be in theFirst quarter at A, and the Earth at a: _Mars_ will be seen, not at[gamma], but at [alpha]; too slow: And when the Moon is at B, and the Earthat b, _Mars_ will be seen at [beta]; yet too slow: till at the {289}Full-moon, the Moon at C, the Earth at c, _Mars_ will be seen at [gamma], its true place, as if the Earth were at T. But then, after the Full, theMoon at D, the Earth at d; _Mars_ will be seen, not at [gamma], but at[delta], too forward: and yet more, when the Moon (at the last Quarter) isat E, the Earth at e, and _Mars_ seen at [epsilon]. If therefore _Mars_(when in opposition to the Sun) be found (all other allowances being made)somewhat too backward before the Full moon, and somewhat too forward afterthe Full-moon, (and most of all, at the Quadratures:) it will be the bestconfirmation of the Hypothesis. (The like may be fitted to _Mars_ in otherpositions, _mutatis mutandis_; and so for the other Planets. ) But this proof, is of like nature as that of the Parallaxis of the EarthsAnnual Orb to prove the Copernican Hypothesis. If it can be observed, itproves the Affirmative; but if it cannot be observed, it doth not convincethe Negative, but only proves that the Semidiameter of the Earths Epicycleis so small as not to make any discernable Parallax. And indeed, I doubt, that will be the issue. For the Semidiameter of this Epicycle, being littlemore than the Semidiameter of the Earth it self, or about 1-1/3 thereof (asis conjectured, in the _Hypothesis_, from the Magnitudes and Distances ofthe Earth and Moon compared;) and there having not as yet been observed anydiscernable _Parallax_ of _Mars_, even in his neerest position to theEarth; it is very suspicious, that here it may prove so too. And whetherany of the other Planets will be more favourable in this point, I cannotsay. * * * * * _ANIMADVERSIONS of Dr. _Wallis_, upon Mr. _Hobs_'s late Book, _DePrincipiis & Ratiocinatione Geometrarum_. _ These were communicated by way of Letter, written in _Oxford_, July 24. 1666. To an Acquaintance of the _Author_, as follows: Since I saw you last, I have read over Mr. _Hobs_'s Book _Contra Geometras_(or _De Principiis & Ratiocinatione Geometrarum_) which you then shewed me. A New Book of _Old_ matter: Containing but a _Repetition_ of what he hadbefore told us, more than once; and which hath been Answered long agoe. In which, though there be Faults enough to offer ample {290} matter for alarge Confutation; yet I am scarce inclined to believe, that any willbestow so much pains upon it. For, if that be true, which (in his_Preface_) he saith of himself, _Aut solus insanio Ego, aut solus noninsanio_: it would either be _Needless_, or _to no Purpose_. For, by hisown confession, _All others_, if they be not mad themselves, ought to think_Him_ so: And therefore, as to _Them_ a Confutation would be _needless_;who, its like, are well enough satisfied already: at least out of danger ofbeing seduced. And, as to himself, it would be _to no purpose_. For, if_He_ be the Mad man, it is not to be hoped that he will be convinced byReason: Or, if _All We_ be so; we are in no capacity to attempt it. But there is yet another Reason, why I think it not to need a Confutation. Because what is in it, hath been sufficiently confuted already; (and, soEffectually; as that he professeth himself not to Hope, that _This Age_ islike to give sentence for him; what ever _Nondum imbuta Posteritas_ maydo. ) Nor doth there appear any Reason, why he should again Repeat it, unless he can hope, That, what was at first False, may by oft Repeating, become True. I shall therefore, instead of a large Answer, onely give you a briefAccount, _what is in it_; &, _where it hath been already Answered_. The chief of what he hath to say, in his first 10 Chapters, against_Euclids_ Definitions, amounts but to this, That he thinks, _Euclide_ oughtto have allowed his _Point_ some _Bigness_; his _Line_, some _Breadth_; andhis _Surface_, some _Thickness_. But where in his _Dialogues_, pag. 151, 152. He solemnly undertakes toDemonstrate it; (for it is there, his 41th _Proposition_:) hisDemonstration amounts to no more but this; That, _unless a Line be allowedsome Latitude; it is not possible that his Quadratures can be True_. Forfinding himself reduced to these inconveniences; 1. That his _GeometricalConstructions_, would not consist with _Arithmetical calculations_, norwith what _Archimedes_ and others have long since demonstrated: 2. That the_Arch_ of a Circle must be allowed to be sometimes _Shorter_ than its_Chord_, and sometimes _longer_ than its _Tangent_: 3. That the sameStraight Line must be allowed, at one place onely to _Touch_, and atanother place to _Cut_ the same Circle: (with others of like nature;) Hefindes it necessary, that these things may not seem Absurd, to allow his_Lines_ some _Breadth_, (that so, as he speaks, _While a Straight Line withits Out-side doth at one place {291} Touch the Circle, it may with itsIn-side at another place Cut it_, &c. ) But I shou'd sooner take this to bea _Confutation of His Quadratures_, than a _demonstration of the Breadth ofa _(Mathematical)_ Line_. Of which, see my _Hobbius Heauton-timorumenus_, from _pag. _ 114. To p. 119. And what he now Adds, being to this purpose; That though _Euclid_'s [Greek:Sêmeion], which we translate, _a Point_, be not indeed _Nomen Quanti_; yetcannot this be actually represented by any thing, but what will have someMagnitude; nor can _a Painter_, no not _Apelles_ himself, draw a _Line_ sosmall, but that it will have some Breadth; nor can _Thread_ be spun soFine, but that it will have some Bigness; (_pag. _ 2, 3, 19, 21. ) is nothingto the Business; For _Euclide_ doth not speak either of such _Points_, orof such _Lines_. He should rather have considered of his own Expedient, _pag. _ 11. That, when one of his (_broad_) Lines, passing through one of his (_great_)Points, is supposed to cut another Line proposed, into two equal parts; weare to understand, the _Middle of the breadth_ of that Line, passingthrough the _middle_ of that Point, to distinguish the Line given into twoequal parts. And he should then have considered further, that _Euclide_, bya _Line_, means no more than what Mr. _Hobs_ would call _the middle of thebreadth_ of his; and _Euclide_'s _Point_, is but the _Middle_ of Mr. _Hobs_'s. And then, for the same reason, that Mr. _Hobs_'s _Middle_ must besaid to have no _Magnitude_; (For else, not the _whole Middle_, but the_Middle of the Middle_, will be _in the Middle_: And, the _Whole_ will notbe equal to its _Two Halves_; but Bigger than _Both_, by so much as the_Middle_ comes to:) _Euclide_'s _Lines_ must as well be said to have noBreadth; and his _Points_ no Bigness. In like manner, When _Euclide_ and others do make the _Terme_ or _End_ of aLine, a _Point_: If this _Point_ have _Parts_ or _Greatness_, then not the_Point_, but the _Outer-Half_ of this Point ends the Line, (for, that the_Inner-Half_ of that Point is not at the End, is manifest, because the_Outer-Half_ is beyond it:) And again, if that _Outer Half_ have _Parts_also; not this, but the _Outer_ part of it, and again the _Outer part_ ofthat _Outer part_, (and so in _infinitum_. ) So that, as long as _Any thingof Line_ remains, we are not yet at the _End_: And consequently, if we musthave passed the _whole Length_, before we be at the _End_; then that _End_(or _Punctum terminans_) has _nothing of Length_; (for, when the _wholeLength_ is past, there is nothing of it left. ) And if Mr. _Hobs_ tells us(as _pag. _ 3. ) that this {292} _End_ is not _Punctum_, but only _Signum_(which he does allow _non esse nomen Quanti_) even _this_ will serve ourturn well enough. _Euclid_'s [Greek: Sêmeion], which some Interpretersrender by _Signum_, others have thought fit (with _Tully_) to call_Punctum_: But if Mr. _Hobs_ like not that name, we will not contend aboutit. Let it be _Punctum_, or let it be _Signum_ (or, if he please, he maycall it _Vexillum_. ) But then he is to remember, that this is only aControversie in _Grammar_, not in _Mathematicks_: And his Book should havebeen intitled _Contra Grammaticos_, not, _Contra Geometras_. Nor is it_Euclide_, but _Cicero_, that is concern'd, in rendring the Greek [Greek:Sêmeion] by the Latine _Punctum_, not by Mr. _Hobs_'s _Signum_. TheMathematician is equally content with either word. What he saith here, _Chap. _ 8. & 19. (and in his fifth _Dial. _ p. 105. &c. )concerning the _Angle of Contact_; amounts but to thus much, That, by the_Angle of Contact_, he doth not mean either what _Euclide_ calls an_Angle_, or any thing of that kind; (and therefore says nothing to thepurpose of what was in controversie between _Clavius_ and _Peletarius_, when he says, that _An Angle of Contact hath some magnitude_:) But, that bythe _Angle of Contact_, he understands the _Crookedness of the Arch_; andin saying, the _Angle of Contact hath some magnitude_, his meaning is, thatthe _Arch of a Circle hath some crookedness_, or, is a _crooked line_: andthat, of equal Arches, That is the more crooked, whose chord is shortest:which I think none will deny; (for who ever doubted, but that a _circularArch is crooked_? or, that, of such Arches, equal in length, _That is themore crooked, whose ends by bowing are brought nearest together_?) But, whythe _Crookedness of an Arch_, should be called an _Angle of Contact_, Iknow no other reason, but, because Mr. _Hobs_ loves to call that _Chalk_, which others call _Cheese_. Of this see my _Hobbius Heauton-timorumenus_, from _pag. _ 88. To p. 100. What he saith here of _Rations_ or _Proportions_, and their _Calculus_; for8. Chapters together, (_Chap. _ 11. _&c, _) is but the same for substance, what he had formerly said in his 4th. Dialogue, and elsewhere. To which youmay see a full Answer, in my _Hobbius Heauton-tim. _ from _pag. _ 49. To p. 88. Which I need not here repeat. Onely (as a _Specimen_ of Mr. _Hobs_'s Candour, in Falsifications) you mayby the way observe, how he deals a Demonstration of Mr. _Rook_'s, inconfutation of Mr. _Hobs_'s Duplication of the Cube. Which when he hadrepeated, _pag. _ 43. He doth then (that it might seem absurd) change thosewords, _æquales {293} quatuor cubis_ DV; (_pag. _ 43. _line_ 33. ) into these(p. 44. L. 5. ) _æqualia quatuor Lineis, nempe quadruplus Recta_ DV: Andwould thence perswade you, that Mr. _Rook_ had assigned a _Solide_, equalto a _Line_. But Mr. _Rook's_ Demonstration was clear enough without Mr. _Hobse's_ Comment. Nor do I know any Mathematician (unless you take _Mr. Hobs_ to be one) who thinks that _a Line multiplyed by a Number will make aSquare_; (what ever _Mr. Hobs_ is pleased to teach us. ) But, That _a Numbermultiplyed by a Number, may make a Square Number_; and, That _a Line drawninto a Line may make a Square Figure_, _Mr. Hobs_ (if he were, what hewould be thought to be) might have known before now. Or, (if he had notbefore known it) he might have learned, (by what I shew him upon a likeoccasion, in my _Hob. Heaut. _ _pag. _ 142. 143. 144. ) _How_ to understandthat language, without an Absurdity. Just in the same manner he doth, in the next page, deal with _Clavius_, forhaving given us his words, pag. 45 l. 3. 4. _Dico hanc LineamPerpendicularem extra circulum cadere_ (because neither _intra Circulum_, nor in _Peripherea_;) He doth, when he would shew an errour, first makeone, by falsifying his word, _line_ 15. Where instead of _LineamPerpendicularem_, he substitutes _Punctum A. _ As if _Euclide_ or _Clavius_had denyed the _Point A. _ (the utmost point of the _Radius_, ) to be in theCircumference: Or, as if Mr. _Hobs_, by proving the _Point A. _ to be in theCircumference, had thereby proved, that the _Perpendicular Tangent A E_ hadalso lyen in the Circumference of the Circle. But this is a Trade, whichMr. _Hobs_ doth drive so often, as if he were as well faulty in his_Morals_, as in his _Mathematicks_. The _Quadrature of a Circle_, which here he gives us, _Chap. _ 20. 21. 23. Is one of those _Twelve_ of his, which in my _Hobbius Heauton-timorumenus_(from _pag. _ 104. To _pag. _ 119) are already confuted: And is the _Ninth_in order (as I there rank them) which is particularly considered, _pag. _106. 107. 108. I call it _One_, because he takes it so to be; though itmight as well be called _Two_. For, as there, so here, it consisteth of_Two branches_, which are Both false; and each overthrow the other. For ifthe _Arch of a Quadrant_ be equal to the _Aggregate of the Semidiameter andof the Tangent of 30. Degrees_, (as he would _Here_ have it, in _Chap. _ 20. And _There_, in the close of _Prop. _ 27;) Then is it not equal to _thatLine, Whose Square is equal to Ten squares of the Semiradius_, (as, _There_, he would have it, in _Prop. _ 28. And, _Here_, in _Chap. 23. _) Andif it be equal to _This_, then not to _That_. For _This_, and _That_, arenot equal: As I then demonstrated; and need not now repeat it. The grand Fault of his Demonstration (_Chap. _ 20. ) wherewith he would nowNew vamp his old false quadrature, lyes in those Words _Page_ 49. _line_30, 31. _Quod Impossibile est nisi _ba_ transeat per _c_. _ which is noimpossibility at all. For though he first bid us _draw the Line R c_, andafterwards the _Line R d_; Yet, Because he hath no where proved (nor is ittrue) that _these two are the same Line_; (that is, that the point _d_ lyesin the _Line R c_, or that _R c_ passeth through _d_:) His proving that _Rd cuts off from _ab_ a Line equal to the Sine of R c_, doth not prove, that_ab_ passeth through _c_: For this it may well do though _ab_ lye _underc. _ (vid. In case _d_ lye beyond the line _R c. _ that is, further from_A_:) And therefore, unless he first prove (which he cannot do) that _A c_( a sixth part of _A D_) doth just reach to the line _R c_ and no further, he only proves {294} that a sixth part of _ab_ is _equal_ to the Sine of_B c_. But, whether it _lye above it_, or _below_ it, or (as Mr. _Hobs_would have it) just _upon_ it; this argument doth not conclude. (Andtherefore _Hugenius's_ assertion, which Mr. _Hobs_, _Chap. _ 21. Would havegive way to this Demonstration, doth, notwithstanding this, remain safeenough. ) His demonstration of _Chap. _ 23. (where he would prove, that _the aggregateof the Radius and of the Tangent of 30. Degrees_ is equal to _a Line, whosesquare is equal to 10 Squares of the Semiradius_;) is confuted not only byme, (in the place forecited, where this is proved to be impossible;) but byhimself also, in this same Chap. _pag. _ 59. (where he proves sufficientlyand doth confesse, that this demonstration, and the 47. _Prop. _ of thefirst of _Euclide_, cannot be both true. ) But, (which is worst of all;)whether _Euclid's_ Proposition be False or True, his demonstration mustneeds be False. For he is in this Dilemma: If that Proposition be _True_, his demonstration is _False_, for he grants that they cannot be both True, _page_ 59 _line_ 21. 22. And again, if that Proposition be False, hisDemonstration is so too; for _This_ depends upon _That_, _page_ 55. _line_22. And therefore must fall with it. But the Fault is obvious in _His Demonstration_ (not in _Euclid'sProposition_:) the grand Fault of it (though there are more) lyes in thosewords, _page_ 56. _line_ 26. _Erit ergo M O minus quam M R_ Where, insteadof _minus_, he should have said _majus_. And when he hath mended thatError, he will find, that the _major_ in _page_ 56. _line penult_, willvery well agree with _majorem_ in _page_ 57. _line_ 4 (where the _Printer_hath already mended the Fault to his hand) and then the _Falsum ergo_ willvanish. His Section of an Angle _in ratione data_, _Chap. _ 22 hath no otherfoundation, than his supposed _Quadrature_ of _Chap. _ 20. And therefore, that being false, this must fall with it. It is just the same with that ofhis 6. Dialogue, _Prop. _ 46. Which (besides that it wants a foundation) howabsurd it is, I have already shewed, in my _Hobbius Heauton-timor. _ _page_119. 120. His _Appendix_, wherein he undertakes to shew a Method of finding _anynumber of mean Proportionals, between two Lines given_: Depends upon thesupposed Truth of his 22. Chapter; about _Dividing an Arch in anyproportion given_: (As himself professeth: and as is evident by theConstruction; which supposeth such a Section. ) And therefore, that failing, this falls with it. And yet this is other wise faulty, though _that_ should be supposed True. For, In the first Demonstration; _page_ 67. _line_ 12. _Producta L fincidet in I_; is not proved, nor doth it follow from his _Quoniam igitur_. In the second Demonstration; _page_ 68. _line_ 34. 35. _Recta L f inciditin x_; is not proved; nor doth it follow from his _Quare_. In his third Demonstration; _page_ 71: _line_ 7. _Producta _Y P_ transibitper _M_;_ is said _gratis_; nor is any proof offered for it. And so thiswhole structure falls to the ground. And withall, the _Prop. _ 47. _El. _ 1doth still stand fast (which he tells us, _page_ 59, 61, 78. Must haveFallen, if his Demonstrations had stood:) And so, _Geometry_ and_Arithmetick_ do still agree, which (he tells us, _page_ 78: _line_ 10. )had otherwise been at odds. And this (though much more might have been said, ) is as much as need to besaid against that Piece. * * * * * Printed with Licence for _John Martyn_, and _James Allestry_, Printers tothe Royal Society. {295} * * * * * _Num. _ 17. PHILOSOPHICAL_TRANSACTIONS. _ * * * * * _Munday_, _Septemb. _ 9. 1666. * * * * * The Contents. _Observations made in several places (at _London_, _Madrid_ and _Paris_, ) of the late _Eclipse of the Sun_, which hapned _June_ 22. 1666. Some Enquiries and Directions, concerning _Tides_, proposed by _Dr. Wallis_. Considerations and Enquiries touching the same Argument, suggested by Sir _Robert Moray_. An Account of several Books lately publish't: Vid. 1. _Johannis Hevelii Descriptio Cometæ, _ A. 1665. Exorti; una cum _Mantissa Prodromi Cometici_. 2. _Isaacus Vossius de Nili & aliorum Fluminum Origine_. 3. _Le Discernement du Corps & de l'Ame_, par Monsieur de _Cordemoy_. _ * * * * * _Observations made in several places, Of the late _Eclipse of the Sun_, which hapned on the 22 of _June_, 1666. _ The Observations that were made at _London_ by Mr. _Willughby_, Dr. _Pope_, Mr. _Hook_, and Mr. _Philips_, are these: The Eclipse began at 5h. 43' h. ' { 3/11 diam. At 6. 00 | 5 dig. At 7. 06 { 4 digits at 6. 07 | 4 dig. At 7. 13 It was { 5 dig. At 6. 13 | 3 dig. At 7. 20 darkned, { 6 dig. At 6. 21 | 2 dig. At 7. 26 { 7 dig. At 6. 39½ | 1 dig. At 7. 32 { 6 dig. At 6. 57 | 0 dig. At 7. 37 Its _Duration_ hence appears to have been one hour and 54 m. Its _greatestObscurity_ somewhat more than 7. Digits. About the middle, between thePerpendicular and Westward Horizontal _Radius_ the Sun, viewing it throughMr. _Boyle_'s 60. Foot-_Telescope_, there was perceived a little of theLimb of the Moon without the Diske of the Sun: which seemed to some of theObservers to come from some shining _Atmosphere_ about the Body either ofthe Sun or Moon. They affirm to have observ'd the _Figure_ of this _Eclipse_, and measuredthe {296} _Digits_, by casting the _Figure_ through a 5 foot _Telescope_, on an extended paper, fix't at a certain distance from the Eye-glasse, andhaving a round figure; all whose _Diameters_ were divided, by 6_Concentrick_ Circles, into 12 _Digits_. The Observations made at _Madrid_ by a Noble Member of the _Royal Society_, His Excellence the Earle of _Sandwich_, as they were sent to the RightHonourable, the Lord Vice-Count _Brounker_, are these; The Eclipse _began_ at _Madrid_ about 5 of the Clock in the morning, at 5h. 15', the Suns _Altitude_ was 6 deg. 55'. The _Middle_ of it was at 6 h. 2', the Suns _Altitude_, 15. Deg. 5'. The _End_ was exactly at 7 h. 5'; the Suns _Altitude_, 25. Deg. 24'. The _Duration_, 2h. 4'. 37. Parts of the Suns diameter remained light. 63. Parts of the same were darkened. The Observations made at _Paris_ by Monsieur _Payen_, assisted by several_Astronomers_, as they were printed in _French_, and addressed to Monsieurde _Montmor_, are these; The _Eclipse_ began there, at 5 h. 44'. 52". _mane_. It ended at 7 h. 43'. 6". So that its _whole Duration_ was 1 h. 58'. 14". The _greatestObscuration_ they assign to have been 7. Dig. 50. M. But they adde, that itseem'd to have been greater by 3 minuts; which M. _Payen_ imputes to aparticular motion of _libration_ of the Suns Globe, which entertain'd thatLuminary in the same _Phasis_ for the space of 8. _min. _ and some_seconds_, as if it had been stopped in the midst of its Course; ratherthan to a tremulous Motion of the _Atmosphere_, as _Scheiner_ would haveit. They intimate that they took the time of each _Phasis_ from half _digit_ tohalf _digit_, as well by a _Pendulum_, as by the _Altitudes_ of the _SunsCenter_ above the _Horizon_, corrected by the _Verticall Paralaxes_ and_Æstivall Refractions_, by which they judged, that though the Time by the_Pendulum_ may be sufficient for _Mechanicall_ Operations, yet 'tis notexact enough for establishing the _Grounds of true Astronomy_. They further conceive that the apparent _Diameters_ were almost equal;seeing that in the _Phasis_ of 6. _Digits_, the _Circumference_ of the_Moons disk_ passed through the _Center_ of that of the _Sun_, so as thattwo Lines drawn through the two _Horns_ of the Sun, made with the _CommonSemi-diameter_ two _Equilateral Triangles_. Next, they affirm, That there was so great a Variation in the _Parallaxes_, by reason as well of the Refractions of the Air, which environs the Earth, as of the Alteration of the Air, which encompasses the Moon, that the_Horns_ of the Sun, there formed by the Shaddow of the Moon, appeared inall kinds of _Figures_; Sometimes inclined to the _Vertical_, sometimes_Perpendicular_ to the _Horizon_, and at last _Parallel_; the _Convexe_part respecting the _Heaven_, and the _Concave_, the _Horizon_. By thecrossing (_so they go on_) of the {297} _Horns_ with the _Angles ofInclination_, it will be easie to those, that have exactly observed them, and that are skill'd in the higher _Astronomical_ Calculations, to computethe _true Place_ of the _Moon_ in her _Orbite_, that so it may be comparedwith that of the _Tables_, and with that, which has been observ'd in otherplaces, for the more precise determinating of the _Difference_ of_Meridians_ (that being the way, esteem'd by _Kepler_ the most certain) andfor making a good Judgment of the defect or exactnesse of the Celestial_Tables_. Then they observe, That the _Beginning_ and the _Middle_ of this _Eclipse_hapned to be in the _North Eastern Hemisphere_, and the _End_, in the_South-Eastern_. The _first Contact_ (as 'twere) of the two Disks wasobserv'd in the _Superior Limb_ of the _Suns Disk_ in respect to the_Vertical Line_, and in the _Inferior_ in respect to the _Ecliptick_: Butthe _Middle_, and the _End_ were seen in the _Superior Limb_, in respectboth to the _Vertical_ and the _Ecliptick_: And (what to this Author seemsextraordinary) both the _Beginning_ and the _End_ of this _Eclipse_ hapnedto be in the _Oriental_ part of the Suns Disk. Lastly, they take notice, that by their Observations it appears, that thereis but little exactness in all the _Astronomical Tables_, predicting the_Quantity_, _Beginning_ and _Duration_ of this Eclipse; Those of_Lansbergius_ importing, That the Obscuration should be of 10. Dig. 48';those of _Ricciolo_, of 9. Dig. 1'; and those of _Kepler_, of 7. Dig. 30'. 16": Again, that the _Duration_ should be of 2h. 2'. Lastly, The_Beginning_ did anticipate the _Ricciolan Tables_ by 5 _minuts_, the _End_by 23; and the _Middle_, almost by 11. In the mean time the Author notes, that the _Rudolphin Tables_ come nearest to the Truth; and withal assuresthe _Reader_ of the goodnesse of the _Instruments_ employed in his_Observations_, and of the singular care, he, together with his skilfulAssistants, took in making them. * * * * * _Some Inquiries and Directions concerning _Tides_, proposed by Dr. _Wallis_, for the proving, or disproving of his lately publish't_Discourse_ concerning them_. The Inquisitive Dr. _Wallis_, having in his lately printed _Hypothesis_ ofTides intimated, that he had reason to believe, that the _AnnualSpring-tides_ happen to be rather about the beginnings of _Febr. _ and_Nov. _ than the two _Æquinoxes_, doth in a late Letter to the _Publisher_, written from _Oxford_ in _Aug. _ last, desire, that some understandingPersons at _London_, or _Greenwich_, but rather nearer the Sea, or upon theSea-shore, would make _particular_ Observation of all the _Spring-Tides_(_New-Moon_ and _Full-Moon_) between this and the End of _November_; andtake account of the _Hour_, and of the _Perpendicular height_: that we maysee, whether those in _September_, or those of _November_ be highest: Andit were not amiss, the Low waters were observed too. Which may be easilydone by a mark made upon any standing Post in the Water, by any {298}Water-man, or other understanding Person, who dwells by the Water-side. It would also deserve (thinks he) to be inquired into, whether, when theTides be highest, the Ebbs be ever lowest, & _contra_; (which is generallyaffirmed, and almost put out of question) or rather (which sutes best withthis _Hypothesis_) whether, when the Tides are highest, both in the_Annual_ and _Menstrual_ Periods, the Low waters be not also highest; andat Neap Tides, the Ebbes also very low. He adds, that he should expect, that the Spring Tides now coming, and thoseat the beginning of _September_, should not be so high, as those at the_middle_ of _September_; and then lower again at the _beginning_ of_October_, and after that, higher at the _middle_ of _October_, and higheryet about the _beginning_ of _November_ (at the usual times of_Spring-tides_ after the _New_ and _Full_. ) * * * * * _Considerations and Enquiries concerning _Tides_, by Sir _Robert Moray_;likewise for a further search into Dr. _Wallis's_ newly publish't_Hypothesis_. _ In regard that the High and Low waters are observed to increase, anddecrease regularly at several seasons, according to the Moons age, so as, about the _New_ and _Full Moon_, or within two or three daies after, in theWestern parts of _Europe_, the _Tides_ are at the _highest_, and about the_Quarter-Moons_, at the _lowest_, (the former call'd _Spring-tides_, theother _Neap-tides_;) and that according to the height and excesses of the_Tides_, the _Ebbes_ in opposition are answerable to them, the heighestTide having the lowest Ebbe, and the lowest Ebbe, the highest Tide; theTides from the _Quarter_ to the _highest Spring-tide_ increasing in acertain proportion; and from the _Spring tide_ to the _Quarter-tide_decreasing in like proportion, as is supposed: And also the _Ebbes_ risingand falling constantly after the same manner: It is wished, that it may beinquired, in what proportion these Increases and Decreases, Risings andFallings happen to be in regard of one another? And 'tis supposed, upon some Observations, made in fit places, by theabove-mentioned Gentleman, though, (as himself acknowledges) not thoroughlyand exactly performed, that the Increase of the Tides is made in the_Proportion_ of _Sines_; the first Increase exceeding the lowest in a smallproportion; the next in a greater; the third greater than that; and so onto the mid-most, whereof the excess is greatest, diminishing again fromthat, to the highest Spring-Tide; so as the proportions, before and afterthe _Middle_, do greatly answer one another, or seem to do so. Andlikewise, from the _highest Spring-tide_, to the _lowest Neap-tide_, the_Decreases_ seem to keep the like proportions; the _Ebbes_ rising andfalling in like manner and in like proportions. All which is supposed tofall out, when no Wind or other Accident causes an alteration. {299} And whereas 'tis observed, that upon the main Sea-shore the Current of theEbbings and Flowings is sometimes swifter, and sometimes slacker, than atothers, so as in the beginning of the Floud the Tide moves faster but in asmall degree, increasing its swiftness constantly till towards the _Middle_of the Floud; and then decreasing in velocity again from the _Middle_ tillto the top of the High water; it is supposed, that in Equal spaces of Time, the Increase and Decrease of velocity, and consequently the degrees of theRisings and Fallings of the same, in Equal spaces of time, are performedaccording to the _Proportion_ of _Sines_. But 'tis withall conceived, that the said _Proportion_ cannot hold_exactly_ and _precisely_, in regard of the _Inequalities_, that fall outin the _Periods_ of the _Tides_, which are commonly observed and believedto follow certain _Positions_ of the _Moon_ in regard of the _Equinox_, which are known not to keep a _precise_ and _constant_ Course: so that, there not intervening equal portions of Time between one New Moon andanother, the Moons return to the same _Meridian_, cannot be alwaiesperform'd in the same Time; and consequently there must be a like Variationof the Tides in the Velocity, and in the Risings and Fallings of the Tides, as to equal spaces of time. And the Tides from New-moon to New-moon beingnot alwaies the same in number, as sometimes but 57, sometimes 58, andsometimes 59, (without any certain order of succession) is another evidenceof the difficulty of reducing this to any great exactness. Yet, because'tis worth while, to learn as much of it, as may be, the _Proposer_ andmany others do desire, That Observations be constantly made of all theseParticulars for some Months, and, if it may be, years together. And becausesuch Observations will be the more easily and exactly made, where the Tidesrise highest, it is presumed, that a fit _Apparatus_ being made for thepurpose, they may be made about _Bristol_ or _Cheap-stow_, best of anyplaces in _England_, because the Tides are said thereabout to rise to tenor twelve fathoms; as upon the coast of _Britanny_ in _France_, they do tothirteen and fourteen. In order to which, this following _Apparatus_ is proposed to be made useof. In some convenient place upon a Wall, Rock, or Bridge, &c. Let there bean _Observatory_ standing, as neer as may be to the brink of the Sea, orupon some wall; and if it cannot be well placed just where the Low wateris, there may be a Channel cut from the Low water to the bottom of theWall, Rock, &c. The Observatory is to be raised above the High water 18. Or20. Foot; and a Pump, of any reasonable dimension, placed perpendicularlyby the Wall, reaching above the High water as high as conveniently may be. Upon the top of the Pump a Pulley is to be fastned, for letting down intothe Pump a piece of floating wood, which, as the water comes in, may riseand fall with it. And because the rising and falling of the water amountsto 60. Or 70. Foot, the Counterpoise of the weight, that goes into thePump, is to hang upon as many Pulleys, as may serve to make it rise & fallwithin the space, by which the height of the Pump exceeds the height of theWater. And because by {300} this means the Counterpoise will rise and fallslower; and consequently by less proportions, than the weight it self, thefirst Pulley may have upon it a Wheele or two, to turn _Indexes_ at anyproportion required, so as to give the minute parts of the motion, anddegrees of risings and fallings. All which is to be observed by_Pendulum-watches_, that have _Minutes_ and _Seconds_, with _Checks_, according to Mr. _Hugens's_ way. And because if the Hole, by which the water is let into the Pump, be aslarge as the Bore of the Pump it self, the weight that is raised by thewater, will rise and fall with an Undulalation, according to the inequalityof the Sea's Surface, 'twill therefore be fit, that the Hole, by which thewater enters, be less than half as bigg as the Bore of the Pump; anyinconvenience that may follow thereupon, as to the Periods and Stations ofthe Floud and Ebb, not being considerable. And to the end, that it may appear the better; what are the _particular_Observations, desired to be made, near _Bristol_ or _Cheap-stow_ bridg, itwas thought not amiss, to set them down distinctly by themselves. 1. The degrees of the Rising and Falling of the water every quarter of anhour (or as often as conveniently may be) from the Periods of the Tides andEbbs; to be observed night and day, for 2 or 3 months. 2. The degrees of the velocity of the Motion of the Water every quarter ofan hour for some whole Tides together; to be observed by a second_Pendul_-watch: and a logg fastened to a line of some 50 fathoms, woundabout a wheel. 3. The exact measures of the Heights of every utmost High-water andLow-water, from one Spring-tide to another, for some Months or ratherYears. 4. The exact Heights of Spring-tides and Spring-Ebbs for some Yearstogether. 5. The Position of the Wind at every observation of the Tides; and thetimes of its Changes; and the degrees of its Strength. 6. The State of the Weather, as to Rain, Hail, Mist, Haziness, &c, and thetimes of its Changes. 7. At the times of observation of the Tides, the height of the_Thermometer_; the height of the _Baroscope_; the height of the_Hygroscope_; the Age of the Moon, and her _Azimuths_; and her place in allrespects; And lastly the _Sun's_ place; all these to _minutes_. And it would be convenient, to keep _Journal Tables_, for all theseObservations, each answering to its day of the Month. For the _Apparatus_ of all these observations, there will be particularlynecessary. A good _Pendulum_-watch. A _Vane_ shewing _Azimuths_ to minute parts. An _Intrument_ to measure the Strength of the Winde. A large and good _needle_ shewing _Azimuths_ to degrees. {301} _Thermometers_, _Barometers_, _Hygroscopes_. These Observations being thought very considerable as well as curious, 'tishoped, that those who have conveniency, will give encouragement andassistance for the making of them; and withall oblige the publick byimparting, what they shall have observed of this kind: The _Publisher_intending, that when ever such observations shall be communicated to him, he will give notice of it to the _publick_, and take care of theimprovement thereof to the best use and advantage. A _Pattern_ of the_Table_, proposed to be made for observing the _Tides_, is intended to bepublished the next opportunity, God permitting. * * * * * _An Account of Several Books lately published_ I. _Johannis Hevelii DESCRIPTIO COMETÆ, Anno Æræ Christianæ MDCLXV. Exorti;unà cum MANTISSA Prodromi Cometici, Observationes omnes prioris COMETÆMDCLIV, ex iisque genuinum motum accuratè deductum, cum Notis &Animadversionibus, exhibens. _ This Book (as the Title it self intimates) undertakes two things. _First_, To give an Account of the _Second_ of the two late Comets, which appeared, when the _other_ was scarce extinct; Concerning which, the Author doth, from the Observations made by himself with a _Sextant_ of 6 foot, anddivided into _minutes_ and _seconds_, assign _both_ its true place (as wellin respect of the _Ecliptick_ as the _Æquator_) _and_ its proper motion;Adding a fair Delineation of its Course, together with the genuineRepresentations of its _Head_ and _Train_, in each day of its apparition;and subjoyning a General Description and Discourse of some of the morenotable _Phenomena_ thereof. It was first seen at _Dantzick_ by theWatchmen, the 5th of _April_ st. N. 1665. And then observed by the _Author_from _April_ 6, about 1½ of the Clock in the morning, till _April_ 20 at 3. In the morning. During which time, it went with a reasonable velocity;making 46 deg. In its Orb, _according to the Order of the Signs_, movingfrom the _Breast_ of _Pegasus_, towards the _Head_ of _Andromeda_, and the_Left Horn_ of _Aries_; having, as 'tis presumed, taken its rise from above_Sagittary_, and run through the _Breast_ of _Antinous_, under _Aquila_ andthe _Dolphin_, to the said _Pegasus_; and so on, as is already expressed. The _Head_ of it is in the Book described of a Colour like that of_Jupiter_, all along much brighter than that of the former Comet, though ofa somewhat less magnitude; having in its middle onely _one_ round, but verybright and big _Kernel_ or Speck, resplendent like Gold, and encompassedwith another more dilute and seemingly uniform matter: its _Tail_ being atfirst, about 17. Deg. And afterwards 20. And sometimes 25 deg. Long, anddivaricated towards the End. _Next_, it is observed, that though this Star did afterwards slacken itspace, yet it retained the vividness of its Colour, both of the _Head_ and_Train_; the _Head_ especially, keeping at the time as well of the lastobservations, as of the {302} first, the brightness of its single _kernel_, though the environing more dilute matter were then almost all lost; itbeing, according to the Author, more and more attenuated, and grown narrow, the nearer the Star approached to the Sun. _Thirdly_, 'tis noted, That this _Comet_ did very much digress from the_Hypothesis_, delivered by _M. Auzout_, in regard that, whereas accordingto that _Hypothesis_, this Star should not arrive to the _Ecliptick_ tillafter the space of 3 months, it arrived there the 28 of _April_. And then, that its first Conjunction with the Sun hapned between the 19 and 20 of_April_, and the second, the last of _April_, not (as _M. Auzout_, wouldhave it) the 15 of _May_. So that he concludes, that this Comet never camedown to the _Pleiads_ and the _Eye of Taurus_, as the Hypothesis of _M. Auzout_ requires, but that from _April_ 20. It did immediately take itscourse towards the Ecliptick, deflecting every day more and more from the_Section_ of a _Great Circle_, to the _Lucida_ of _Aries_, arriving at the_Ecliptick_ the last of _April_, about the 8th or 10th deg. Of _Taurus_;not in _July_ about the 8th of _Gemini_, and the _Eye of Taurus_. _Fourthly_, He intimates, that if this Comet had appeared some weekssooner, it would have confronted the former Comet, being yet in its vigourand of a conspicuous bigness, in the same place, where that was, viz. The_Head of Aries_. _Fifthly_, He observes, that this Star in progress of time became_Retrograde_, whence it came to pass, that in the Months of _June_ and_July_ it did not appear again before the Rising of the Sun, though the Sunleft it far behind: whereas, if it had proceeded toward the _Eye ofTaurus_, it would have appeared again in the morning. _Sixthly_, He maintains, that this Comet was not the same with the former;which he thinks may be demonstrated, onely by a due Delineation of boththeir Course upon the _Globe_; where he saith it to be evident, that theformer could never come to the _Head_ of _Pegasus_, as moving already in_February_ in a streight Course about the _Head_ of _Aries_; Besides, thatthe _former_ went in the very beginning in a _Retrograde_ motion; but_this_ perpetually in a direct one: _that_, about the end, very slow, itsHead lessning and growing dark; _this_ swift enough, with its headconspicuous and bright. To which he adds, that the whole Course of theformer was made under a quite different _Angle_ of the _Orbite_ and_Ecliptick_, and a different Motion of the _Nodes_ from the latter: As alsothat their _Faces_ differed very much from one another; the _first_exhibiting all along a matter, which as to its density and rarity, alteredfrom day to day exceedingly, whereas the _second_ retained (to the Authorsadmiration, who affirms, never to have observed the like) all the time hesaw it, one and the same round, dense and bright Speck or Kernel. All which he concludes 1, With an Intimation of his sense concerning twoother Comets, pretended to have been lately seen, _One_ at _Rome_, aboutthe {303} _Girdle of Andromeda_, in the Months of _February_ and _March_, 1664. The other in _Germany_ in _Capricorne_, about _Saturne_ in the headof _Sagittary_, during the Months of _September_ and _October_, 1665. 2ly, With an Advertisement of what he has done in that important Work for theAdvancement of _Astronomy_, the due _Restitution of the Fixt Stars, vid. _That he has almost finish't it; himself alone, without trusting to anyother mans labour, that was not directed by him. The _Second_ Part of this Book (the _Mantissa_ to the _ProdromusCometicus_) endeavours to justifie the Authors Observations touching theformer Comet, excepted against by M. _Auzout_, in several particulars; as1. That it had not pass'd to the _First_, but _Second_ Star in _Aries_, andhad mov'd in quite another Line, than He had described. 2. That its _propermotion_ about the end of _January_ and the beginning of _February_, 1665. Had not been rightly assigned. 3. That the _Bignesse_ of its _Diameter_ hadnot been truly delivered; Nor 4. The _Faces_ of its _Head_ in due mannerrepresented. To all which the Author endeavors to answer: 1. By delivering all hisObservations of that Comet, thereby to shew, what care and diligence he hadused, _particularly_ to make out, how great its _Diurnal motion_ had been;in what proportion, and how far, it decreased, and where and in what degreeit increased again: Which being, as he conceives, duly and exactly deduced, and demonstrated, he esteems it afterwards to be easie for every one, versed in these matters, certainly to collect and to judge, what way theComet, after it became invisible to the naked Eye, and could be no longerobserved with _Sextants_ and _Quadrants_, had taken, and what Line it haddescribed. 2, By subjecting all those Observations, with great diligenceand labour, to a rigid _Calculus_, thereby to obtain, for every day, the_Longitudes_, _Latitudes_, _Right Ascensions, Declinations_, _Propermotion_, _Angle_ of the _Ecliptick_ and the _Æquator_, and the _Nodes_ ofthat Comet; for the construction of an _Ephemerides_ of its whole Motion. From all which he pretends to prove, that he has not erred in hisObservation of _February_ 18, nor been prepossest by any _Hypothesis_, nordeluded by any _Fixt Star_, as M. _Auzout_ thinketh; but that near the_First Star_ of _Aries_ there _then_ appear'd a _Phænomenon_, most like tothat Comet, that was seen some dayes before, if compared with theObservations make thereof _Febr. _ 12, 13, 14. Though he will not hithertopositively determine, whether that _Phænomenon_, which appear'd to him_February_ 18. Was {304} indeed that very Comet, which he saw with hisnaked Eye, and observed with his Geometrical Instruments, the said 12, 13, and 14. Dayes of _February_; or whether it was another, and whether he hadlost that Comet, which moved towards the _Second Star_ in _Aries_: butleaves it to the Learned World, and particularly to the _Royal Society_, after they shall have well examined and considered all his Observations, and the _Calculus_ raised therefrom, to judge of this, and the otherparticulars in controversie. II. _Isaacus Vossius de NILI et ALIORUM FLUMINUM ORIGINE_. It was _Numb. _14. Of these _Transactions_, that gave an account of the _Cause_ of the_Inundation of the Nile_, as it was rendred by Monsieur _de la Chambre_:_This_ is to give you another, not only of the _Inundation_, but also ofthe _Origine_ of that, and of _other Rivers_, as it is delivered byMonsieur _Isaac Vossius_, who undertakes in this Book to shew; 1. That those _Subterraneous Channels_, through which several_Philosophers_ teach, that the Sea discharges it self into the Rivers, arenot only imaginary, but useless, in regard 'tis impossible for the water torise from the Subterraneous places up to the Mountains, where commonly theSources of Rivers are. 2. He explicates, why, if a Pipe be put into a Bason full of Water, thewater is seen more raised in the Pipe, than in the Bason, and rises higheraccording as the Pipe is narrower; On the contrary, if the same Pipe be putinto a Bason full of Quicksilver, the Quicksilver stayes lower in the Pipe, than in the Bason. The reason, which he renders hereof, is, That as theWater sticks easily to all it touches, it is sustain'd by the sides of thenarrow Pipe wherein it is included: And indeed, if the Pipe be quite drawnout of the Water, the Water doth not all fall out, but so much of itremains, as the sides of the Pipe could sustaine: Whence it is, that theWater which is kept up by the Walls of the Tube, weighing no longer uponthat which is in the Bason, is thrust upwards, and keeps it self raisedabove its Levell; but the Quicksilver not adhering so easily, as Water, toBodies it touches, is not sustained by the sides of the Tube, and so mountsnot above its Levell, but rather descends below it, because the Pipe, whichis streight, hinders the endeavor that is in the _Mercury_ to rise to itsLevel. He adds, that this Observation makes nothing for the Explication ofthe _Origine of Rivers_; because, though it be true, that the Water {305}by this means rises above its Levell, yet it does never run out at the topof the Pipe. Having said this, he answers to the other Arguments, commonlyalledged to maintain this Opinion. 3. He pretends, that all Rivers proceed from a _Colluvies_ or _Rendevous_of Rain-waters, and that, as the Water, that falls upon _Hills_, gathersmore easily together, than that which falls in _Plaines_, therefore it is, that Rivers ordinarily take their Source from _Hills_. Thence also comes it(saies he) that there are more _Rivers_, than _Torrents_, in the _TemperateZones_; and, on the contrary, more _Torrents_, than _Rivers_, in the_Torrid Zone_: For, as in hot Climats the Mountains are far higher, theWater, that descends from them with impetuosity, runs away in a littlewhile, and formes such Collections of Water, as soon dry up, but in coldClimats, the Waters do not run away but slowly, and are renew'd andrecruited by Rain, before they are quite dryed up; because the Hills arethere lower, and so the Bed of Rivers hath lesse declivity. Having thus discoursed of _Rivers_ in _General_, he treats of the _Nile_ in_particular_; and there 1. Observes, That the Order of the Seasons of the Year is quite invertedunder the _Torrid Zone_. For, whereas it should be then Summer, when theSun is near; and Winter, when the Sun is farther off: Under the _TorridZone_ 'tis never lesse hot, than when the Sun is nearest; nor more hot, than when the Sun is farthest off: So that to the people that live betweenthe _Æquinoctial_ and the _Tropicks_, Summer begins about _Christmass_, andtheir Winter, about St. _Johns_ day. The reason whereof is, (_saith he_)that when the Sun is directly over their Heads, it raises abundance ofvapors, and draws them so high, that they are presently converted intoWater by the coldnesse of the Air; whence it comes to passe, that then itrains continually, which does refresh the Air; but when the Sun is fartheroff, there falls no more rain, and so the Heat becomes insupportable. 2. He proves by many recent Relations, that the _Sources_ of the _Nile_ areon this side of the _Æquinoctial_ in _Æthiopia_, of which he gives a veryaccurate _Mappe_, correcting many faults which _Geographers_ are wont tocommit in the Description of the Kingdom of the _Abyssins_, which theybelieve to be much greater than indeed it is. {306} 3. This supposed, he easily gives an account, why the _Nile_ yearlyoverflows about the end of _June_: For, as at that time there falls muchrain in _Æthiopia_, it must needs be, that the _Nile_, whose source is inthat Country, should then overflow, when those rains begin, and subside, when they cease. There are besides, in this Book, two other _Tracts_. In the _first_, M. _Vossins_ endeavours to maintain the Doctrine, he had deliver'd in his Book_De Lumine_, and to shew, that the _Soul_ of Animals is nothing but _Fire_, that there are no invisible Atoms; nor so much as any Pores, even in theSkin of man. Here he treats also of _Refractions_, and alledges theExamples of several persons, who have then seen the Sun by the means ofRefraction, when really He was under the _Horizon_. In the _second_, He discourses of some points of the _Mechanicks_; andrelates among other things, that the _Arrows_ and _battering Rams (Aries)_of the Antients did as much execution, as our _Muskets_ and _Canons_; andthen, that the Vehemence of the percussion depends as much upon the Lengthof the percutient Body, as upon the velocity of the Motion. He adds, thatthe Length of a Canon ought not to exceed 13 foot, and that a greaterlength is not onely useless, but hinders also the effect of the Gun, notbecause the Bullet is thrown out of the Gun, before all the powder is fired(as some believe;) but because the Bullet is then beaten back into the Gunby the Air, re-entring into it with impetuosity, when the flame is extinct. III. _LE DISCERNEMENT DU CORPS ET DE L'AME_, par M. _de Cordemoy_. This _French_ Treatise (but very lately come to the _Publisher's_ hands)examines the different Operations of the Soul and Body, and the Secret oftheir Union, pretending to discover to every one, what he is, and what istransacting within him. It consists of six Discourses. [Sidenote: * _It sounds hard, To say, An _extended_ substance is_indivisible_. _] 1. In the _first_, the Author examines the Notions, we have in _general_ of_Bodies_ and _Matter_; of _Quantity_; of _Qualities_; of _Place_; of_Rest_; of _Motion_; of _Vacuity_; of _Forms_: to shew what is to beunderstood by these Terms, which cause all the perplexity that is in theordinary _Physicks_. He begins with taking notice, that hitherto_Philosophers_ have had no _distinct_ notions of _Bodies_ and _Matter_, from the want whereof he conceives, that almost all the Errors in Common_Physiology_ have {307} sprung. To rectify which, he defines _Bodies_ to be* _Extended Substances_, and _Matter_ an _Aggregate of Bodies_. Whence heinferrs, that _Bodies_ are Indivisible and _Matter_ divisible; a _Body_being nothing but _one_ and the _same_ substance, whose differentextremities are inseparable, because they are the extremities of one andthe same Extension, and, in a word, of one and the same Substance; but_Matter_ being nothing but an Association or Collection of Bodies, 'tisevident, (_saith he_) it must be divisible. This doctrine he so muchinsists upon, that he conceives, Nature cannot subsist, if a Body in thesence he takes it, be divisible; and that _Motion_ and _Rest_ cannot beexplicated without it. As for _Quantity_, he makes that to be nothing butMore or Less Bodies; not allowing, that each Body should be a Quantity, though it be a part of Quantity; no more than an _Unite_ is a Number, though it make part of a Number: so that _Quantity_ and _Extension_ are twodistinct things with him, the _first_ belonging properly to _Matter_, thelast to a _Body_. Touching _Vacuity_, he conceives, that the Bodies, whichcompose a mass, are not every where so near one another, as not to leavesome interval in several places. Neither does he think it necessary, thatthose intervals should be fill'd up; nor unconceivable, that there shouldbe no Body between two Bodies; which touch not one another. And when 'tissaid, that those intervals cannot be conceived without Extension, and thatconsequently there are Bodies that replenish them, he frankly pronouncesthat not to be true; and affirms, that though it may be said, that betweentwo Bodies, which touch not one another, other Bodies may be placed of soor so many feet, &c: yet ought it not to be inferred, that therefore they_are_ there, but onely, that they are thus placed, that there _may_ be putbetween them so many Bodies, as joyned together would compose an Extensionof so many feet. So that one conceives onely, that Bodies _may_ be placedthere, but not that they _are_ there: and as we can have an _Idea_ of manyBodies, though none of them be in being; so we can conceive, that someBodies _may_ be put between others, where really there are none. And when'tis alledged, that if all the Bodies, that fill a vessel full, weredestroyed, the sides of the vessel would be closed together; He professes, he understands not that ratiocination, nor can conceive, what one Body doesto the subsistence of another, more than to sustain themselves mutually, when they are thrust by the neighbouring ones: and therefore sees not, whythe sides of the vessel should close, if nothing did thrust them together;but understands clearly, that two Bodies may well subsist so far from oneanother, that one might place a great many Bodies between them, or none atall, and yet they neither approach to, not recoil from one another. {308} 2. In the _Second_, he examines the _Changes_, which he knows in Matter, and makes it his business to explicate all those that respect _Quantity_, _Qualities_ and _Forms_, by _Local Motion_, esteeming that needs no other. 3. In the _third_, he explains the Motion of _Artificial_ Engins, and thatof _Natural_ ones, by one and the same Cause; endeavouring among otherthings to shew, that the Body of an Animal is moved after the same mannerwith a Watch. That cause of motion he makes the _Materia Subtilis_; and thefiner or subtiler that is, the better and fitter he conceives it to be topreserve Motion. 4. In the _Fourth_, he teaches, that though Experience seems to evince, that the Soul moves the Body, and that one Body moves an other; yet thereis nothing but God, that can produce any notion in the World, and all otherAgents, which we believe to be the _Cause_ of this or that Motion, are nomore but the _Occasion_ thereof. In doing this, he advances certain_Axioms_, and Conclusions, which are in short, a. The _Axioms_: That no substance has that of it self, which it can loose, without ceasing to be, what it is: That every body may loose of its motion, till it have no more left, without ceasing to be a Body: That we cannotconceive but two sorts of substances, _vid. _ a _Spirit_ (or _That whichthinketh_) and a _Body_, wherefore they must be considered as the Causes ofall, that happens, and what cannot proceed from the one, must necessarilybe adscribed to the other: That to _Move_, or to cause motion, is anAction: That an Action cannot be continued but by the Agent, who began it. b. The _Conclusions_: That no _Body_ hath Motion of it self: That the FirstMover of Bodies not a Body: That it cannot be but a _Spirit_, that is theFirst Mover: That it cannot be but the same Spirit, who has begun to moveBodies, that continues to move. In the _Fifth_, He treats of the Union of the Body and Soul, and themanner, how they act one upon the other; and esteems it not more difficultto conceive the Action of Spirits upon Bodies, and of Bodies upon Spirits, than to conceive the Action of Bodies upon Bodies: the cause of the greatdifficulty in understanding the two former, arising (according to him) fromthence, that we will conceive the one by the other, not considering, thatevery thing acting according to its own nature, we shall never know theaction of one Agent, if we will examine it by the notions we have ofanother, that is of a quite differing nature. Here he notes, that theAction of Bodies upon Bodies is not {309} more known to us; than that ofSpirits upon Bodies, or of Bodies upon Spirits; and yet most men admirenothing but _this_, believing to know the _other_; whereas he Judges, thatall things being well examin'd, the Action of Bodies upon Bodies is no moreconceivable, than that of Spirits upon Bodies. Mean while the opinion ofthe Authour touching this subject, is, That the union of Soul and Bodyconsists onely in this, that certain motions of the Body are followed bycertain _Cogitations_ of the Soul, and, on the contrary, that certainThoughts of the Soul are follow'd by certain _Motions_ of the Body. And, having supposed, that Bodies are said to act upon one another, when theycause some change suitable to Extension; and Spirits to act upon oneanother, when they cause some change suitable to a Thought; he infers, thatwhen a Body acts upon a Spirit, that cannot be by causing any change ofmotion, of figure, or parts, as having none of all these; nor when a Spiritacts upon a Body, that cannot be by producing any change of Thought, ashaving none: But, when this Body, or its motion, or figure, or other thing, depending upon its nature, can be perceived by a Spirit, so as, upon thatoccasion, this Spirit has thoughts, it had not before, it may be said, thatthe Body has acted upon this Spirit, for as much as it has caused all thechange in it, whereof it was capable according to its nature. In the _Sixth_, After he hath shew'd, what is to be understood by what wecall _Soul_, and by what we call _Body_, he labours to make it out, that weare much more assured of the Existence of the Soul, than of that of theBody, which he conceives he can prove from hence, that we cannot doubt, that we think, because even doubting is thinking; but one may doubt, whether one has a body, for several reasons, which he alledges, and thinksso cogent, that he concludes, it is not evident to him by the light ofreason, that he has a Body. But supposing, there be Bodies, he examines, what are the Operations, that belong to the Soul, and what those, thatbelong to the Body; and lastly, what those, that result from the Union ofboth: And then explains, how all those operations are perform'd, andparticularly, _Sensation_; where he shews, that the Nerves, holding at oneend to the Brain, whereof they are but Allongations, and being at the otherend extended to the extremities of the Body; when an Object comes to touchthose exterior ends of the Nerves, the interior ones in the Brain arepresently shaken; and cause different sensations according to thediversitie of Nerves, and the differing manner, in which they are shaken. And to shew, that 'tis this shaking, that causes Sensation, he notes, thatif any thing shakes the interior parts of the Nerves, though the object beabsent, the Soul has presently the same {310} sensations, as it would have, if it were present. As, if one should knock on's head forcibly against awall, the shaking, which the blow gives to the Brain, moving the interiorextremities of the Nerve, which causes the sensation of Light, the Soul hasthe same sensation, which it would have, if it saw a thousand Candles: Onthe contrary, if the interior extremities of the nerves are not shaken, though the object be present, it causes no sensation; whence it comes, thatif a strong Ligature be made upon the middle of the Arm, and the hand bethen prickt, no pain is felt, because the shaking of the nerves that arepricked, being stopped by the Ligature, cannot reach to the extremities ofthe Nerves, that are within the Brain. * * * * * _Advertisement. _ The following _Errata_, left by the _Press_ in _Num. _ 16, the _Reader_ isdesired thus to correct. Page 269. Lin 27. Read, _motion of B above the Center; G. Is also_, with a_Semi-colon_ after the word _Center_. P. 274. L. 13, r. _it to do to the_. P. 277. L. 24. R. _natural days_. P. 281. L. 16. R. _of his_. Ib. L. 27. R. _a notion_. P. 293. L. 4. R. _enough without_. Ib. L. 43. R. _to the Sineof_. P. 294. L. 1. R. _to the Sine of_. * * * * * _LONDON_, Printed for _John Martin_ and _James Alestry_, Printers to the RoyalSociety. 1666. {311} * * * * * _Numb. _ 18. PHILOSOPHICAL_TRANSACTIONS. _ * * * * * _Munday_, _October_ 22. 1666. * * * * * The Contents. __Patterns_ of the _Tables_ proposed to be made for _Observing of Tides_; promised in the next foregoing _Transactions_. Other _Inquiries_ touching the Sea. Some Considerations touching the _Parenchymous_ parts of the Body. Observables concerning _Petrification_. A Relation from _Paris_, of a kind of _Worms_, that eat out Stones. Some promiscuous Observations made in _Somersetshire_. A Problem for finding the Year of the _Julian Period_, by a new and very easie Method. An Account of some Books, not long since publish'd, which are, _1. Tentamina Physico-Theologica de Deo_, Authore _Samuele Parkero. 2. Honorati Fabri Tractatus duo; Prior, de Plantis et de Generatione Animalium; Posterior, de Homine. 3. Relation du Voyage de l'Evesque de Beryte, par la Turquie, la Perse, les Indes_, &c. Per Monsieur de _Bourges_. _ * * * * * __Patterns_ of the _Tables_ proposed to be made for _Observing of Tides_, promised in the next foregoing _Transactions_; by Sir _Rob. Moray_. _ In performance of what was promised in the last of these _Papers_ forObserving the _Tides_, here are subjoyned _Patterns_ of the _Tables_ therementioned; _One_, for marking the _precise Time_ of the High waters andLow-waters during one Month; that is, between _New_ and _New_ Moon, or_Full_ and _Full_ Moon. The _other_, for marking the _Degrees_ of theRisings and Fallings of the Water in _Equal_ spaces of Time, and the_Velocity_ of its motion at _several_ heights: The _Degrees_ of _Heat_ and_Cold, &c. _ The _Times_, assigned in the _first_, to the High waters and Lowest Ebbs, are taken out of Mr. _Wing_'s Almanack, for this present year 1666, as hecalculates them for the Month of _September_ for _London Bridge_. Only, whereas he takes notice but of _one_ High-water for every day, _Here_ areset {312} down the Times of the other, and the two Ebbs intervening, bysubdividing the _Differences_, he assignes between two Tides, equallyamongst them. In all which, though there may be Errors, that is not to beconsidered, seeing the Dissein is to Correct and State the _Times_ of the_Tides exactly_ by _Experiments_, after this method. Mr. _Wing_ states theHigh waters to fall out at _London-Bridge_ constantly, when the Moon is 46. Deg. 30. Min. To the _West-ward_ of the _Meridian_. For the Times, he marksfor them, are made up by adding every day 3. Hours, 6 minutes, to those inhis _Table_ for knowing the Time of the Moons coming to the South. The _First Table_ consists of _two_ Parts, and each part of _four Columns_. The _first_ part marks the Tides and Ebbs from the day of the _New_-Moon toits _Full_: The _other_, from the _Full_ to the next _New_. The _firstColumn_ in both parts hath the day of the Month and Week; _M. _ standingevery where for _Morning_ and _A. _ for _Afternoon_. The _third_ column haththe _Character_ of the day of the Week prefixt to the Hour and Minute ofthe High-water, and answering to the day of the Month. The _last_ Columnhath the same for the time of Low-water, varying the _Character_ of theday, as often as the low-water falls out more early than the High-water. Inthis _Example_ between the said _New_ Moons there falls out in all just 57. Periods of the Tide or Flowing water, and 58. Of the Ebb or Low water;which numbers vary according to the Intervals of the Moons changes, butwith what constancy and exactness, is to be inquired after: Which whosoeverundertakes to do, may keep such a _Table_, as is here proposed, in a Bookby it self. The _other_ Table doth in 9. _Columns_ comprehend the particularObservations of the _Degrees_ of the Rising and falling of the Tides, andthe other things specified at the Tops of them: The _first_ Column markingthe Hour and Minut common to all the several Observations. Each hour isdivided in 3. Equal Parts, that number of Observations being only pitch'tupon by way of _Example_: The numbers may else be varied at pleasure, whenother more frequent Observations are thought fit to be made, or when theyprove too frequent and laborious; though the most frequent are mostdesirable, till competent information of all particulars be attained. The _Rising_ of the Tide from Low-water to the highest pitcht of the fullSea, is here supposed to be 60. Foot: And the Degrees of its rising every20. Minuts, to be in the _Proportion_ of _Sines_, The whole time of Flowingsupposed to be 6. Hours. But this _Example_ will serve for marking the_Spaces_ of the Increasing or Rising, as well as of the falling of thewater, in order to the investigation of their _Proportions_ to one another, when the _Duration_ of the Tide exceeds 6. Hours by any number of _minuts_, as well as for just 6. Hours; seeing they may be easily collected from anyNumber of Observations; their precise Time and that of the Duration of thewaters Rising and Falling (that is, the just interval between theHigh-Water and Low-water) being known: This Calculation by _Sines_, beingonly set down as a _Conjecture_, flowing from Observations of the Motion ofthe water in its Rising and Falling, {313} which seems to observe this orsome such like Proportion; which is supposed still to hold in _all_ Tides, be the _Duration_ what it will; the Increase still continuingproportionably till the very midle of the Hight and Duration, andDecreasing afterwards in the same manner: Which whether it be so indeed ornot, is that, which is desired to be known. There is the like Proportion here supposed to be in the _different degrees_of the _Velocity_ of the Current of the Water after _Equal_ spaces ofTimes, as in its Rising and Falling: And so it is markt in the _Third_Column. But because the _true Velocity_ of the Current of the Water, raisedabove the Levell 456/1000 of a foot, is unknown, it is by way ofSupposition set at Ten feet in one Minute of an Hour, which being oncestated, the rest distant from each other by the space of 20. Minutes of anHour, are set down according to the same _Proportions_ of _Sines_ beforesuggested. It being supposed, that of the _Velocity_ of the Current of theTide, after it hath flowed 20 minuts of an hour, be such, as a Log of Woodplaced in the Water will move 10 foot in the space of one minute of time, at the middle of the Tide it will in the like space of Time move 114 f. 276/1000, and so proportionably at other times: Which, howsoever theseProportions shall be found by Experiments to fall out, may be not unworthyof the pains and charges requisite to acquire the knowledge of it. For, besides the satisfaction it may afford upon other accounts, it may possiblybe of no small use to those, who need an exact reckoning of their Shipsrunning, when the Velocity of the Current of the Tide may be necessary tobe known; lest through the defect of the knowledge of that, especially whenit is reckoned less than indeed it is, the Ship be thrown in the night uponShores, Rocks or Sands, when they reckon themselves to be far from them. The Numbers in the 4, 5, 6, 7, and 8. _Columns_ are set down at random, only for _Examples_ sake; there being no difficulty in the apprehension ofit, and imitating of it in setting down the true Hights and Variations ofthe _Thermometer_, _Baroscope_, &c. The Use whereof is so vulgarly known, that there needs no further Direction concerning them. But if any personwho would make these Experiments, do not know the fabrick or use of any ofthe Instruments requisite for some of these Observations, nor where to havethem, he may address himself to Mr. _Shortgrave_, one of the _Operators_ ofthe _Royal Society_, lodged in _Gresham Colledge_, from whom he willreceive full satisfaction about these things. But the labour employed in the Observations of the Heat, Cold, &c. Requiredto be taken notice of in order to the Ends proposed in the former _Tract_, and others that may be of no less delight than advantage, will be muchretrenched, when Dr. _Christopher Wren_ puts in practice, what he someyears ago proposed to the _Royal Society_ concerning an _Engine_ with a_Clockwork_, which may perform these Observations in the last enumerate_Columns_, without being toucht or lookt after but once or twice a day. The Tables themselves follow, {314} _A Perpendicular Line divided into _Signes_, supposed to be the _Periods_of the Risings and Fallings of the Tides, as is in the other Tablerepresented. _ [Illustration] 1666. Age of Time of High water. Time of Low water. Sept. The moon ho. Mi. Day. Hour. Min. Day. Hour. Min. Mo. 3. New Mo. 2. 57. Morn. Mo. 9. 8. Morn. 8. 38'. 3. 19. Aftern. 9. 30. Aftern. Tu. 4. Tu. 3. 41. M. Tu. 9. 51½ M. 4. 2. A. 10. 12½ A. We. 5. We. 4. 23. M. We. 10. 33¼ M. 4. 43½ A. 10. 53¾ A. Th. 6. Th. 5. 4. M. Th. 11. 14½ M. 5. 25. A. 11. 35½ A. Fr. 7. Fr. 5. 46. M. Fr. 11. 56½ M. 6. 7. A. Sa. 0. 17½ M. Sa. 8. Sa. 6. 28. M. 0. 39½ A. 6. 51. A. Su. 1. 2½ M. Su. 9. Su. 7. 14. M. 1. 23½ A. 7. 37. A. Mo. 1. 48¼ M. Mo. 10. Mo. 8. 0. M. 2. 13. A. 8. 26. A. Tu. 2. 39. M. Tu. 11. 1. Qu. Tu. 8. 52. M. 3. 5. A. 10 A. 9. 18. A. We. 3. 31. M. Mo. 12. Mo. 9. 44. M. 3. 57¾ A. 10. 11½ A. Th. 4. 25¼ M. Th. 13. Th. 10. 39. M. 4. 53. A. 11. 7. A. Fr. 5. 21. M. Fr. 14. Fr. 11. 35. M. 5. 49. A. Sa. 15. Sa. 0. 3. M. Sa. 6. 17. M. 0. 31. A. 6. 45. A. Su. 16. Su. 0. 59. M. Su. 7. 13. M. 1. 27. A. 7. 41. A. Mo. 17. Mo. 1. 55. M. Mo. 8. 9. M. 2. 23. A. 8. 36¾ A. Tu. 18. Full. Tu. 2. 50½ M. Tu. 9. 4¼ M. 11. 10'. 3. 19. A. 9. 31¼ A. We. 19. We. 3. 45. M. We. 9. 58½ M. 4. 11. A. 10. 25½ A. Th. 20. Th. 4. 39. M. Th. 10. 52½ M. 5. 6. A. 11. 20. A. Fr. 21. Fr. 5. 34. M. Fr. 11. 48. M. 6. 2. A. 0. 16. A. Sa. 22. Sa. 6. 30. M. Sa. 0. 44. A. 6. 58. A. Su. 1. 12½ M. Su. 23. Su. 7. 27. M. 1. 41½ A. 7. 36. A. Mo. 2. 10¼ M. Mo. 24. Mo. 8. 24½ M. 2. 38¾ A. 8. 53. A. Tu. 3. 6¾ M. Tu. 25. Tu. 9. 20½ M. 3. 34¼ A. 9. 48. A. We. 4. 1¾ M. We. 26. Last Q We. 10. 15½ M. 4. 29¼ A. 3. 11' 10. 43. A. Th. 4. 56½ M. Th. 27. Th. 11. 10. M. 5. 23½ A. 11. 37. A. Fr. 5. 48. M. Fr. 28. Fr. 11. 59. M. 6. 10. A. Sa. 29. Sa. 0. 21. M. Sa. 6. 32. M. 0. 43. A. 6. 54. A. Su. 30. Su. 1. 5. M. Su. 7. 16. M. Octob. 1. 27. A. 7. 38. A. Mo. 1. Mo. 1. 49. M. Mo. 7. 59. M. 2. 9. A. 8. 19. A. Tu. 2. Tu. 2. 29. M. Tu. 8. 39. M. New. 2. 49. A. 8. 59. A. We. 3. 1. 38' We. 3. 9. M. We. 9. 19. M. 1666. Rising, and Thermo- Hygro- Sept. 3. Fall of Tides metre scope Hour. M. Foot /1000 Inch /10 Inch /10 Velocity of Baro- Azimuth. Force the Current scope of the Wind Foot /1000 Inch /10 deg. Deg. 00, 000. 0, 000. Weather XII. 00. 00, 000. 6. 7. 28. 1. 3. 4. S. To W. 50. 3. 0, 456. Rain great 20. 10, 000. 6. 7. 28. 1. 3. 4. S. To W. 57. 3. 1, 353. Rain great 40. 36, 250. 6. 8. 28. 1. 3. 4. S. To W. 60. 3. 2, 211. Rain small I. 00. 48, 587. 6. 8. 28. 1. 3. 3. S. W. 45. 4. 3, 000. Rain small 20. 66, 658. 6. 8. 28. 1. 3. 2. S. W. 30. 4. 3, 696. Rain very small 40. 81, 053. 6. 9. 28. 2. 3. 1. S. W. 36. 4. 4, 284. Fair but cloudy II. 00. 93, 289. 6. 9. 28. 2. 3. 0. S. W. 39. 5. 4, 740. Fair and warm 20. 103, 289. 6. 8. 28. 1. 2. 7. S. W. 42. 5. 5, 049. Warm and cloudy 40. 110, 724. 6. 8. 28. 2. 2. 3. S. W. 19. 6. 5, 211. Sunshine III. 00. 114, 276. 6. 8. 28. 2. 2. 0. S. W. 60. 5. 5, 211. Sunshine and clear 20. 110, 724. 6. 7. 28. 3. 2. 1. S. W. 73. 5. 5, 049. Sun clouded 40. 103, 289. 6. 7. 28. 3. 2. 0. S. W. 90. 6. 4, 740. Cloudy IIII. 00. 93, 289. 6. 6. 28. 3. 2. 1. S. W. 90. 6. 4, 284. Hazy about the Horiz. 20. 81, 053. 6. 6. 28. 4. 2. 3. N. W. 87. 6. 3, 696. Misty 40. 66, 658. 6. 5. 28. 4. 2. 3. N. W. 70. 7. 3, 000. Misty V. 00. 48, 487. 6. 4. 28. 4. 2. 3. N. W. 59. 7. 2, 211. Clearing up 20. 36, 250. 6. 2. 28. 5. 2. 3. N. W. 50. 6. 1, 353. Clear 40. 10, 000. 6. 1. 28. 5. 2. 1. N. W. 60. 5. 0, 456. Sunshine VI. 00. 00, 000. 6. 0. 28. 5. 2. 0. N. W. 60. 4. 0, 000. Sunshine {315} * * * * * _Other Inquiries Concerning the Sea. _ The _Publisher_ of these _Tracts_, knowing that the Honorable _RobertBoyle_ had not left unconsidered the Natural History of the _Sea_, of whichSubject the late, and these present Papers, have entertained the _Reader_as to the Observables of its _Flux_ and _Reflux_; He was on this occasioninstant, with that Gentleman to impart to him, for publication, these Headsof Inquiries, he had drawn up, touching that Subject: Which having obtained(though the _Author_ desires, they may be lookt upon as unfinisht) he thussubjoyns. What is the Proportion of Salt, that is in the Water of differing Seas; Andwhether in the same Sea it be always the same? And if it be not, how muchit differs? [Sidenote: * _This last Clause containing difficult _Quaere_ and that mayseem something odd, Mr. _Boyl_ thinks fit to note, That having recommendedthis matter, among others, to a learned Physician, that was sailing into_America_, and furnished him with a small _Hydrostaticall_ Instrument, toobserve from time to time the Differences of Gravity he might meet with;This account was returned him, That he found by the Glass, the Sea-water toincrease in weight, the nearer he came to the _Line_, till he arrived at acertain Degree of _Latitude_; as he remembers, it was about the 30th; afterwhich, the Water seemed to retain the same specifick gravity, till he cameto the _Barbadoes_, or _Jamaica_. _] What is the Gravity of Sea-waters in reference to Fresh Waters and to oneanother: Whether it vary not in Summer and Winter, and on other Scores? Andwhether in the same Season its Gravity proceed _only_ from the greater orlesser Proportion of Salt, that is in it, and not sometimes from otherCauses? And what are the differing Gravities of the Sea-water, according tothe Climats. * What are the Odors, Colours and Tasts, observable in Sea-water? What is the depth of the sea in several places, and the Order of itsincrease and Decrements? And whether the Bottom of the Sea does always risetowards the Shore, unless accidentally interrupted? Of the Bottom of the Sea, and how it differs from the Surface of the Earth, in reference to the Soyl, and evenness or Roughness of the Superficies, Andthe Stones, Minerals and Vegetables to be found there? What the Figuration of the Seas from North to South, and from East to West, and in the several Hemispheres and Climats? What communication there is of Seas by Streights and SubterranealConveyances? Of the Motion of the Sea by Winds, and how far Storms reach downwardstowards the Bottom of the Sea? [Sidenote: * _The particulars whereof (saith the Author) are here omitted;Sir _Robert Moray_ and Dr. _Wallis_ having by there more accurate inquiriesabout _Tides_ made them needless. _] Of the grand Motions of the Bulk or Body of the Sea; especially of theTides *; Their History as to their Nature and Differences. {316} What power the Sea hath to produce or hasten Putrefaction in someBodies, and to preserve others; as Wood, Cables, and others that are sunkunder it? Of the Power ascribed to the Sea to eject Dead Bodies, _Succinum_, _Ambergris_? Of the shining of the Sea in the night? What are the Medical vertues of the Sea, especially against _Hydrophobia_? What is its vertue to Manure Land? And what are the Plants, that thrivebest with Sea-water. * * * * * _Some Considerations concerning the _Parenchymous_ parts of the Body. _ These were communicated by the inquisitive M. _Edmund King_ at the Instanceof the _Publisher_, as follows; The _Parenchymous_ parts of the Body, are by _Anatomists_ generallysupposed to be in very many places wholly _void of Vessels_; designedchiefly to fill up Cavities and interstices between the Vessels, and toboulster up the same, and to convey them through the parts. But having many years endeavoured to excarnate several parts of the Body, _viz. _ the Liver, Lungs, Spleen, Kidneys, &c. (not to name the _PlacentaUteri_, which seems to be _Parenchymous_ too;) and being very desirous tomake a _Scheme_ of the Vessels of any of these, what ever they were, I fixtupon; I found, notwithstanding all my care to preserve the Vessels, when Iwas freeing them, as heedfully as I could, from the supposed _Parenchyma_, that in every breach, I made, either with my fingers or otherwise, all myendeavors were destructive to my purpose: and that, upon examination ofthose bits, much of which is called _Parenchyma_, I met in them moreVessels, than I had preserved in the parts whence they came: And though theportion were never so small, yet my bare eye could make this discovery;much more could I, when assisted by a _Microscope_, perceive, I haddestroyed more Vessels than preserved, in despite of the exactest care, Iwas capable to use. And being not a little concern'd, that I shouldundertake to preserve the Vessels by such a Cause, as I saw plainly to betheir definition (were the part never so big, or never so small) I was bothconfounded and tired. For I saw (and so must any, that will attempt thiswork) in my endeavouring to preserve one Vessel of a traceable magnitude, Ispoiled an infinite number of others less discernable, which were as trulyVessels, as the other, differing only in size and figure (as toappearance. ) Then reviewing what mischief I had done in every place, quitethrough the whole Tract of my Fingers, Knife, &c. I begin to think with myself, That it was not impossible for these parts to consist wholly ofVessels curiously wrought and interwoven (probably for more Uses, than isyet known;) And the {317} consideration, which came into my mind, of apiece of fine Cloth (which consists of so many several minute Hairs, call'd_Wool_) was no discouragement to this opinion. Yet I durst not bepresumptuous as to indulge my self too much in it; much less to venterpresently to speak of such a thing, which seem'd to contradict so manyLearned Men's belief. But being restless, till I might receive moresatisfaction in the thing, I iterated experiments over and over; some ofwhich prov'd so successful to my apprehension, that I was encouraged in theyear 1663. And 1664 to discourse of it to several very worthy Persons, asMr. _Boyl_, Sir _William Petty_, Dr. _Williams_, Dr. _Lenthal_, Dr. _JasparNeedham_, Dr. _Samson_, (who afterwards sent me a Letter from _France_, intimating the acquaintance he had made with the learned _Steno_, who hathsince published something of the same Discovery) Mr. _Daniel Cox_, and Dr. _Samuel Parker_, &c, who doubtless cannot but remember, that then I relatedto them, I found much cause to believe, that that substance commonly called_Parenchyma_, was in most, if not in all its _Parenchymous_ parts, full ofVessels; however it had been imagin'd by all, I could ever meet with, toconsist in great part of a substance, in many places void of Vessels, designed for such uses, as are above mentioned. Against which I have now further to alledge, 1. That I observe in a pieceof _Musculous_ flesh (so call'd) either raw, rosted, or boiled, &c. That ifI so far extend it as to make it to be seen through, I can (assisting myEye) perceive it full of Vessels placed as thick as is possible to beimagin'd, (the fat if there be any, being first removed) there appearingthen nothing but vessels, yet so as with a _Microscope_ may be seenthrough, when they are extended. 2. That, if any one, as he is at dinner, take a piece of flesh, and begin either at the head or tail of a _Muscle_, he may divide it _in infinitum_ all along from head to tail, withoutbreaking any thing of that, called Flesh, only these transverse _Fibres_, that seem to stitch them together, and (as I am apt to think) pass throughthe very Bodies of the smallest of them, and quite through the whole Muscleup the Cutaneous porosities; so that there is not one of these small_ducts_, that run _per longitudinem_, but 'tis furnisht with a sufficientnumber of outlets, when need requires, though too minute to suffer any_alimentary_ juice to pass transversly (in a living Body) or any otherliquor, when the Body is dead and cold. But to wave their use at present, and to return to what I was saying. Compress between the fingers this bitof flesh, and you shall find the Juice, especially if the Meat be Hot, togo before your fingers toward either end you please; but if you compressboth ends, you shall see it swell into the middle; and again, if you pressthe middle, it will run out at both ends. But further, suppose a piece offlesh, called _Parenchyma_, as big, or as little as you please, in any partof the Body, and let me prick it with a Needle, where you shall appoint; ifyou feel it, I presume you will acknowledge, a _Nerve_, or a _Fibrilla_, related to it, is touch'd; If you feel it not, I am sure some liquor eithersanguineous or other, will follow the Needle; And from whence can thatcome, but out of Vessels? unless {318} accidentally, as by a _Contusion_, &c. , it be extravased, in which case my Argument will not be injured, because the part is depraved, whereas I speak of the parts, as they are intheir natural State. To confirm and illustrate all which, I desire, that the following_familiar_ Observations may be considered: 1. If a Horse, fat and fair to look on, without a hollow to be seen betweenhis Muscles, be rid extreme hard, and into a great sweat, and then kept oneday without water or moist meat, you shall see him took so thin in manyplaces as in the _musculous_ parts, that you will hardly believe it to bethe same Horse, especially if he be (as the Phrase is among Horse-masters)a _Nash_ or _Wash-Horse_. The cause of which thinness will easily begranted to be only an exhaustion of Juice, expended out of the Blood, whichdid stuff out these Vessels. And whoever, that is used to ride hard, shallobserve, how thick this foul Horse breaths, and at what a rate he will reekand sweat, will not much wonder at the alteration. But if the Horse be ahardy one, and used to be hard ridden, then you will see, that one daysrest, and his belly full of good meat and drink, will in one day or twoalmost restore him to his former plight, the food being within that shortspace of time so distributed, that all the Vessels will be replenish'dagain, as before. And the cleaner the Horse is, the sooner recruited, andthe less sign of hard riding will appear. This seems to shew the facility, with which the Juice, called Blood, passeth; Which surely, if there weresuch a thing as a _Parenchyma_ might by several accidents (not difficult tomention) be so deprav'd in several parts of it, that it might lose itsreceptive faculty; than which it may be thought to have none of greateruse, being supposed to be without Vessels. 2. Discoursing sometimes with _Grasiers_ in the Country, about the Pastureof Cattle, I have been informed by them, that, if they buy any Old Beasts, Oxen, or Cows to feed, they choose rather those that are as poor as can be, so they be sound; because that, if they are pretty well in flesh, what theythen add to them by a good pasture, though it make them both look and sellwell, yet it will not make them eat so well, their flesh proving hard andvery tough: Which some may suppose to be the age of _Parenchyma_; and so itis of that so called. But if those Beasts be old and extremely poor, thenthey feed very kindly, and will be not only very fat but spend well, likeyoung ones, and eat very tender. Of which I take the reason (excluding a _Parenchyma_ now) to be this. Whenan Oxe or a Cow is grown old, and in an indifferent plight as to his_flesh_ (for so it is called) all those Vessels having been kept at thatsize for the most part, have contracted a tenseness and firmness, and their_fibers_ less extensive, nor so fitted for the reception of more unctuousparticles to relaxe them; and that additional unctuous matter, whichoccasions fatness, is forced to seek new quarter any where (often remotefrom Muscles) where it can be with least difficulty received; sometimes toone place, sometimes to {319} another, as may be seen in Shambles. Whereas, if there were such a thing as a _Parenchyma_, that certainly would, like ahungry Sponge, immediately swell up in several parts, (which without muchdifficulty might be discover'd in the dissection) and more eminently, whereit should find the pores most potent: And in the dissection of such Musclesit would be very strange, not to find some, if not many, pieces of them invarious shapes, to the great inconvenience of the parts, in which they areseated: Which yet I confess I could never find in any Muscle unless it werewhere there had been a _Contusion_, or an _Impostume_, or the like. Butaccording to my opinion of the _Parenchymous_ parts, the reason, why theFlesh of a very lean Ox or Cow, that hath got new Flesh in a good pasture, eats tenderer, seems to be this: That in a very lean Beast the Vesselsdesigned for admitting and distributing the nourishing Juice, are so nearcontracted, and lye so close together; that, when once they are relax'd; byfresh and unctuous nourishment, they extend every way in all _extensive_parts, until in a short time the whole Creature is, as it were, created anew, having got new flesh upon old bones. And the necessity of extremeextension makes all those parts, that are, as has been said, for theadmission of nourishment, so thin and fine, that it will make the leanBeast, put into a rich pasture, eat young and tender: Whereas one of thesame Age, that never was very poor, fed in the same pasture, shall eat hardand tough. 3. It has been observed, that Corpulent Persons in some Diseases, thatseize on them, do fall away to wonder, not only in the Wast, but in theArms, Legs, and Thighs; and the very Calves of the Legs have been observedso flaccid and loose, that one might wrap the skin about the bones. Thereason whereof, according to the opinion deliver'd, may be easily rendredto be, A great Consumption of the Stock of Liquors, that in Health kept theVessels turgid; Which Vessels I suppose to make up those Muscles. But whenthe Pores are obstructed, that the nourishment is hindred (which then alsouses to be but sparingly administred) and sweats, either spontaneous, orforced, are large, there must needs be a great expence of those Liquors, the supply being but inconsiderable: which cannot but contract all theseducts of all sorts nearer together, and make them much less in themselves, meerly from Exhaustion: Or, if there should be no sweats, the internal Heatspends the spirits, and dries up the Liquors; the consequence whereof mayreasonably be presumed to be this Flaccidity of parts, and great and suddenChange, made in them; not that there is need of any _Parenchyma_ to fill upthese Muscles considering what hath been said. Mean while, I humblyconceive, that if it be in any part of a Muscle, their Ingenuity, thatplead for it, will put them upon some experiments, to bring it to OcularDemonstration, either in Living or Dead Muscle, any kind of flesh, raw, rosted, boyl'd, or in what they can best make it out. And when I shall beconvinc'd of an Errour in what I have discoursed, I shall beg pardon forgiving the Occasion of the trouble of that Experiment, which shall prove a{320} _Parenchyma_ in any Muscle; and think my time well spent in receivinga full satisfaction of the ungroundedness of my opinion; and readily submitto the Author, with a grateful acknowledgement of my Obligation to any onethat shall rectifie me in my mistake, if it be one. * * * * * _Observables touching _Petrification_. _ Though much hath been already said and written of _Petrification_, yet 'tisconceived, that all that comes so far short of a competent stock for thecomposing of a perfect _History of Petrification_, that the incompleatnessthereof ought to awaken the more diligent attention of the Curious, and tocall in their aid for Additions, thereby so to encrease and to complete the_Materials_ for that work, that it may the better serve to clear and makeout the Cause of that Transmutation. And that the rather, because if it layin the power of humane Skill (by the knowledge of _Nature_'s works) toraise _Petrification_, or to allay, or prevent it, or to order and directit (which perchance in time might be attained the said way) much use mightbe made of this Art; especially if it could be made applicable to hinderthe Generation of the Stone and Gravel in humane Bodies, or to dissolve theStone, where 'tis formed; besides other valuable Uses, that might beexcogitated. Upon this Consideration, care is, and further _will be_ taken in thesePapers, to record, among other Observables of Nature, what shall becommunicated of this kind of _Change_. In _Num. _ 1. 2. And 5. Several Relations have been made belonging to thisArgument. Much of it, together with considerable Reflections may be seen inMr. _Boyle_'s _Essay of Firmness_: In _Helmont de Lithiase_, where, amongother remarques, is recited the Testimony of _Paræus_ of a _PetrifiedChild_ seen at _Paris_, and by the Owner used for a _Whetstone_: In_Densingius_'s Historia _Infantis in Abdomine inventi, & in duritiemlapideam conversi_: In Mr. _Hook_'s _Micrography_, and in others. To omitnow, what has been related (but perhaps not well enough attested) byAuthors, concerning the stupendious Petrifications of whole Companies ofMen, and Troops of Cattle; by _Aventinus_, lib. 7. _Annal. Bojorum_; by_Purchas_ in his _Pilgrimage_ p. 416. In fol. Printed at _London_ 1614, and, (of a Troop of _Spanish_ Horsemen) by _Jos. Acosta_ lib. 3. C. 9. To all which, the curious Dr. _Beale_ now adds a Narrative of a Stone, notlong since taken out of the Womb of a Woman of his neighbourhood neer_Trent_ in _Somersetshire_, by incision, and afterwards perfectly cured, though she had born the Stone with extreme torments for. 8. Or 9. Years. The operation he relates to have been made in _Easter_ last; after whichtime, he affirms to have seen the Stone, and weigh'd it in Gold Scales, where it wanted somewhat of four Ounces, but had lost of the weight, itformerly had, {321} being very light for a Stone of that Bulk. He furtherdescribes to be of a whitish colour, lighter than Ash-colour; perchance(_saith he_) not unlike to that recited out of _Scaliger_ by Mr. _Boyle_ inhis _Essay of Firmness_ pag. 238. _qui aëris contactis postea in gypseamtum speciem tum firmitatem concreverat_. It had no deep asperities, and hadsomewhat of an Oval figure, but less at one end, than a Hen-Egge, andbigger and blunter at the other end, than a Goose egge. This Stone, (so he concludes) is intended for the _Royal Society_, with theTestimony of the _Chirurgion_, that perform'd the Operation, and otherWitnesses of special credit; where also will be annexed the _manner_ ofOperation. It appears by this last clause (to add that on this occasion) that thisWell-wisher to the Improvement of all usefull knowledge, has taken noticeof that considerable _Collection of Curiosities_, lately presented to thelately nam'd Society for their _Repository_, by the Publick-mindedGentleman Mr. _Daniel Colwall_, a very worthy and useful Member of thatBody: To which Repository whatsoever is presented as rare and curious, willbe with great care, together with the _Donors names_ and their_Beneficence_ recorded, and the things preserved for After-ages, (probablymuch better and safer, than in their own private Cabinets;) and in progressof Time will be employed for considerable Philosophical and Usefullpurposes; of which perhaps more largely in another place. * * * * * _A Relation of a kind of _Worms_ that eat out Stones. _ This is taken out of a Letter, written by one _M. De la Voye_ to _M. Auzout_, to be found in the 32. _Journal des Scavans_; as follows. In a great and very ancient Wall of Free-Stone in the _Benedictins Abby_ at_Caen_ in _Normandy_, facing Southward, there are to be found many Stonesso eaten by Worms, that one may run his hand into most of the Cavitieswhich are variously fashion'd, like the Stones, which I have seen wroughtwith so much Art in the _Louvre_: In these cavities there is abundance oflive-Worms, their excrement, and of that Stone-dust, they eat. Between manyof the Cavities there remain but leaves, as it were, of Stone, very thin, which part them. I have taken some of these living Worms, which I found inthe eaten Stone, and put them into a Box with several bits of the Stone;leaving them there together for the space of eight days; and then openingthe Box, the Stone seem'd to me eaten so sensibly, that I could no longerdoubt of it, I send you the Box and the Stones in it, together with theliving Worms: and to satisfie your Curiosity, I shall relate to you, what Ihave observed of them both _with_ and _without_ a _Microscope_. {322} These Worms are inclosed in a Shell, which is grayish and of the bigness ofa Barly-corn, sharper at one end, than the other. By the means of anexcellent _Microscope_ I have observ'd, that 'tis all overspread withlittle Stones and little greenish Eggs; and that there is at the sharpestend a little hole by which these Creatures cast out their excrement, and atthe other end, a somewhat bigger hole, through which they put out theirheads and fasten themselves to the Stones, they gnaw. They are not so shutup, but that sometimes they come out, and walk abroad. They are all black, about two _Lines_ of an inch long and three quarters of a _Line_ large. Their Body is distinguish't into several plyes, and near their head theyhave three feet on each side, which have but two Joynts resembling those ofa Lowse. When they move, their Body is commonly upwards, with their mouthagainst the Stone. They have a big head, somewhat flat, and even, of thecolour of a Tortoise-Shell, braunish, with some small white hair. Theirmouth is also big; where may be seen four kinds of Jaw-bones, lyingcrossewise, which they move continually, opening and shutting them like apair of _Compasses_, with four branches. The Jaws on both sides of themouth are all black, the nether Jaw hath a point like the Sting of a Bee, but uniform. They draw threds out of their mouth with their fore-feet, using that point to range them, and to form their Shells of them. They haveTen Eyes, very black and round, which appear to be bigger than a Pins head. There are five of them on each side of the head, standing after thismanner, [Illustration] But besides these Worms, I have found, that _Mortar_ is eaten by aninfinite number of small Creatures, of the bigness of Chees-Mites. Thesehave but two Eyes, and are blackish. They have four feet on each sidepretty long. The point of their Muzzle is very sharp, as that of a Spider. I send you but one of them, though I had abundance, but they are dead andlost. It may be, you'l find some at _Paris_, seeing that in the old Mortarbetwixt Stones, that is found in Walls made with rubbish, there is greatstore of them, together with great plenty of their little Eggs. I have notyet examined, whether these be those, that in the surfaces of all theStones, where they are met with, make little round holes, and small tracesand impressions, which make them look like _Worm-eaten Wood_. But 'tisprobable, they are such. It should be observed, whether these Worms do nottake Wings, and all the other appearances of Caterpillars; and whether theyare not to be found in plaister that is full of holes, in Bricks, in GreetyStones, and in Rocks. You may observe more of them in Walls exposed to the _South_, than inothers; and that the Worms, that eat the Stone, live longer, then those, {323} that eat the Mortar, which keep not above eight days alive. I haveobserved all their parts with a very good _Microscope_, without which, anda great deal of attention, 'tis difficult to see them well. I have seen other very old Walls altogether eaten, as those of the _Temple_at _Paris_, where I could find no Worms, but the Cavities were full ofShells of various kinds, diversly figur'd and turn'd: all which I believeto be little Animals petrified. * * * * * _Some promiscuous Observations, made in _Somerset shire_, and imparted bythe above-mentioned Dr. _Beale_. _ His words are these, in a Letter to the _Publisher_, of the 24. _Septemb. _1666 at _Yeovill_ in _Somersetshire_; I have two or three remarks, perhaps not unworthy to be recorded forfurther application in like cases of time and place 1. In the Moores from hence towards _Bridgewater_, in the extreme drought, we have endured this Summer, some lengths of pasture grew much soonerwhithered and parched, than the other pasture. And this Parched part seem'dto bear the length and shape (in gross) of Trees. They digg'd, and found, in the place, _Oakes_ indeed, as black as Ebony. And hence they have beeninstructed to find and take up many hundreds of Oakes, as a neighbour ofgood credit assures me. This advertisement may be instructive for otherparts, as _Kent_, _Essex_, _Lincoln_, &c. [Sidenote: * _This had somewhat of a Vitriolate taste. But the Experimentbeing made with greater quantities of this water, which questionless willbe done, the nature and kind of it may be better known. _] 2. My Cosen _Philips_ of _Montague_ has in his pastures of _Socke_, aboutthree miles off, a large Pool, to which Pigeons resort; but the Cattle willnot drink of it, no not in the extream want of water in this drought. Tothe taste it is not only brackish, but hath other loathsome tasts. In aVenice-glass it looked greenish and clear, just like the most greenishCider as soon as it is perfectly clarified. I boyl'd a Pint of it in aPosnet of Bell-Mettall (commonly used to preserve Sweatmeats:) suddenly ityeilded a thick froth, whence I scumm'd half a score Spoonfulls; of whichthe inclosed is a part, * Suffering the water to be boyl'd all away, itleft much of the same on the sides and bottom of the Posnet. 3. From _Lamport_, towards _Bridge water_, Eeles are so cheap in the frostsof Winter, that they vend them for little. Their abundance is from hence, that as the people walk, in the frosty Mornings, on the banks of river, they discern, towards the edges of the banks, some parts _not hoar_, as therest, but _green_; where searching the holes of the banks they find heapsof Eeles. {324} * * * * * _A Problem for finding the Year of the _Julian Period_ by a new and veryeasie Method. _ This occurs in the _Journal des Scavans_ n^o. 96. As it had been proposedcommunicated to the Learned _Jesuit DE BILLY_. Viz. Multiply the _Solar_ Cycle by 4845. And the _Lunar_, by 4200. And that ofthe _Indiction_, by 6916. Then divide the Sum of the Products by 7980. Which is the _Julian Period_: The _Remainder_ of the Division, withouthaving regard to the _Quotient_, shall be the year required after. E. G. Let the Cycle of the _Sun_ be 3; of the _Moon_ 4; and of the_Indiction_, 5. Multiply 3. By 4845, and you have 14535; and 4. By 4200. Comes 16800; and 5. By 6916. Comes 34580. The Sum of the products is 65915, which being divided by 7980. Gives 8. For the _Quotient_, and the number2075. Which remains, is the Year of the _Julian Period_. Some learned Mathematicians of _Paris_, to whom the said _P. De Billy_, didpropose this _Problem_, have found the Demonstration thereof; as the same_Journal_ intimates. * * * * * _An Account of some Books, not long since published. _ I. TENTAMINA PHYSICO-THEOLOGICA DE DEO, _Sive_ THEOLOGIA SCHOLASTICA, _adNormam Novæ & Reformatæ Philosophiæ concinnata, & duobus libriscomprehensa. Quorum altero, de Dei existentia adversus Atheos & Epicureosex ipsorummet Principiis disputatur; altero, de ejusdem Essentia &Attributis; primò secundum Theologiam Ethnicam, ubi explicatur, Quantumhactenus Alii in Gentilium sententiis, de summi Numinis Natura eruendis, hallucinati fuerint; deinde secundum Theologiam Christianam: Et quid deDivina Essentia ac Attributis statuendum sit, diceretur. Quibus postremòaccedit specialis Dissertatio de Primo Numinis Attributo, ÆTERNITATE_. Authore _Samule Parkero_, A. M. This Treatise, published the last year, would sooner have been taken noticeof in these _Tracts_, had it not escaped the _Publishers_ view till oflate, when he, upon serious perusal, found it very worthy the recommendingit to all sorts of persons; and particularly to those who either pleasethemselves with that fond opinion, _That Philosophy is the Apprentiship ofAtheisme_; or hearken to the aspersions, that are generally laid upon the_Reformation_ of _Philosophy_. This excellent piece removes both these; and being joyned and compared withthe truly Noble Mr. _Boyle_'s Considerations in his _First part_ of the{325} _Usefulness of Experimental-Natural Philosophy_, will stronglyevince, How Much that Philosophy, which searches out the real Productionsof Nature (the true Works of God) does manifest the Divine Glory more, thanthe Notionals of the Gentiles. This Author (now a Fellow of the _Royal Society_) delivers his Matter intwo Books. Lib. 1. Cap. 1. Atheists are disappointed of the Authority of _Epicurus_, and of other Antient Philosophers, for their gross Atheisme. Cap. 2. The beautiful Frame of the World evinceth the ArchitectonicalAuthor and Governor. Cap. 3. The admirable Contrivance in the Structure of Mankind, and ofAnimals, does more conspicuously shew the Deity. Cap. 4. The Atheist caught in his own Net, or convinced by the true forceof his own Arguments. Cap. 5. The Arguments devised against Atheists by _Des Cartes_, and drawnfrom the _Idea's_ of our Mind, examin'd and found imperfect and invalid. Lib. 2. Cap. 1. The opinions of the Gentiles concerning God, unduly appliedto the _Deity_, which we worship: but properly to be understood by them ofthe _Sun_, or of the _Soul of the World_. Cap. 2. More expresly proved, that the Antient Philosophers conceived, the_Soul of the World_ to be God. Cap. 3. The Historical Theology of the Gentiles for the most part is undulyapplyed or accommodated to the Holy Scriptures. Cap. 4. The Divine Substance, Immensity, Incomprehensibility, Invisibility, explicated, as far as our weak reason does teach. Cap. 5. The Divine Perfections, and other Attributes and Affections, howfar explicable. Cap. 6. The Eternity of God, how apprehended. These are in short the Heads of the Book, which is yet but in Latin. Itwere to be wisht, the Author would make it speak his own lively _English_. II. HONORATI FABRI _Soc. Jesu Theologi, Tractatus duo; quorum Prior est dePlantis & de Generatione Animalium; Posterior de Homine. _ As the Matter of this Book is considerable, so is the order and dependenceof all its parts excellent; in regard that all the Propositions are rangedaccording to a Geometrical method, and so well disposed, that the latter doalways suppose the former, and seem to depend all of them upon certainevident principles, whence they flow by a natural consequence. This _Volume_ contains two Treatises. The _First_ is divided into 5. Books. In the _four first_, he treats of_Plants_, and distributes them into three _Classes_; some growing _in theEarth_, as _Trees_; others, growing upon _Plants_, as _Mosse_; and a thirdsort growing upon _Animals_, as _Hair_, _Horns_, and _Feathers_. He examinsand considers the {326} Parts of all these Plants and their Use, themanner, how they are produced, and nourished; and their differentQualities. He discourses also of Bread, Wine, Oyle, and the other Mixtures, that are made of Plants. In the _Fifth Book_, he treats of the _Generation of Animals_, where hedelivers many curious matters, explicating in a very easie and familiar waythat Argument, which hath always been lookt upon, as one of the obscurestin Natural Philosophy. The _Second_ Treatise consists of 7. Books; wherein the Author considers, what appertains to _Man_. He discourses _first_, of Digestion, of theCirculation of the Bloud, and of the Use of the principal parts of theHumane Body. _Next_, he treats of the Senses, External and Internal; of allthe Motions of the Body, both Natural and Voluntary, of the sensitiveAppetite, and the Passions; _Thence_ he proceeds to the Temperaments, Habits, Instinct, Sleep, Sickness, &c. _Lastly_, passing to the _RationalSoul_, he endeavours to demonstrate the Immortality thereof, and to explainalso the Manner, how it worketh upon the Body, and is united with the Body;where he omits not to reason of all the Powers of the Soul, of Liberty, andof the Operations of the Understanding and Will. In _general_, the Author makes it his study, for the explicating of themost perplext Difficulties, to shew, that Nature works not but by verysimple and easie wayes. In _particular_ he intersperses several curious remarks. _E. G. _ He teacheshow to make _Perspectives_, that magnifie Objects, without Glass; tellingus, that when an Object is look't upon through a small hole, it appearsmuch greater than it is; and that therefore, if instead of Glasses one didcast before ones eyes two _Plates_ having little holes in them, it wouldfurnish us with a new kind of _Perspectives_, more commodious than those ofGlasses, which spoil the Sight by reason of the refraction of the Rayes, caused thereby. _Again_, He renders the cause of that common, butsurprising, effect of Painters, drawing certain Pourtraictures, which seemto look directly upon all their Beholders, on what side soever they placethemselves: _Videl. _ That in those Pictures, the Nose it a little turned toone side, and the eyes to the other. Whence it comes, that such picturesseem to look to the right side, because the Eyes are indeed turned thatway; but they appear also to look to the left, because the point of theNose is turned that way, and the Table, whereon the Picture is drawn, beingflat the Looker on perceives not, that the Eyes are turned th'other way;which he would do, if the Eyes of the Pourtrait were convex: Whence itcomes, that no Figure can be made embossed, which looks every way. The art, which he teaches of making _Parsley_ shoot out of the ground in afew hours, is this. Infuse the seed of it in Vinegar; and having sown it ingood ground cast on it a good quantity of the Ashes of Bean-Cods, andsprinkle it with Spirit of Wine, and then cover it with some linnen. Hementions also; that if you calcine Earth, and then water it well, it will{327} produce a great variety of different Herbs, and that the Ashes ofCorn burnt, being sown, have sometimes produced other Corn. To add that by the by, this Author is not so addicted to _Aristotle_, as tobe on his side, when he thinks Truth is not. He hath emancipated himselfconsiderably from the _Scholastick_ way of Philosophing. He dares maintain, that the Vegetative and Sensitive Souls are not _Substantial_ Forms; andthat it is with Plants and Animals, as with Artificial things, the Formwhereof results from the Union and Disposition of the parts. According tothis _Hypothesis_ he explicates all the Operations of Plants and Animals, without having any recourse to the Soul. He avers also, that there are no_Species Intentionales_, and no Habitudes, and that the Animal Spirits, which Philosophers commonly believe to be necessary for all the Operationsof Life, are useless. It might also be observed out of this Author, what he discourses of theGeneration of Animals by Putrefaction; of the Cause of intermittent_Feavers_, and of the Animal Instinct, and of many other particulars; wereit not better to refer the curious to the Book it self. III. _RELATION DU VOYAGE de l' Evesque de Beryte, par la Turquie, la Perse, les Indes, _&c. _ jusques au Royaume de Siam, & autres lieux_; par M. _deBourges, Prestre_ &c. This Author imploying his Pen chiefly, according to his design, to give anAccompt of the Success, the Undertakers of this Voyage had, in propagatingthe Christian Faith in the remoter parts of the World, and relating on thatoccasion, What number of Churches they have founded in _Cochin_, _China_, and the Kingdom of _Tonquin_, (in which latter alone he affirms, that thereare more than three hundred thousand Christians;) being I say principallyintent upon that Subject, he seems not to have made many Philosophicalobservations in those places. Mean while he does good service to those thathave occasion to travel into the _East-Indies_ mostly by Land, bydescribing the passage, they took thither; which was, That they embarquedat _Marseilles_, in _September_, the most convenient and favourable seasonfor that Voyage; whence Ships do ordinarily pass every Month from _Syria_, reckoning one Month for the time of Sayling, to _Alexandretta_. Thence to_Aleppo_, counting one Month more for the Stay, to be made there to meetthe _Caravane_ for _Babylon_, and six weeks more for the march from_Aleppo_ to _Babylon_, where a fortnight will pass before an opportunityhappen to embarque upon the _Tyger_ for _Balsora_; which Journey willrequire a fortnight more: And about this time it will be about the end of_January_. Thence is always conveniency to pass from _Congo_, 4 daysJourney from _Comoron_ or _Gombroun_, to which latter part there is alsofrequent occasion to pass by Sea from _Balsora_, which will take up some 15or 16. Days Sail. There (vid. At _Comoron_) you will every year meet with_English_, _Portugal_, _Dutch_, and _Moorish_ Vessels, from _Surat_, from_October_ till the end of _April_, for they are obliged to be at _Surate_, before the end of _May_, because all the ports of those {328} _Indies_ areshut the 4. Ensuing months, by reason of the danger of that _Sea_. But besides this Direction, the Book is not quite destitute of _Natural_Observations. It relates, 1. How Diamonds are found and separated in_Golconda_; They take of the Earth, held to be proper to form them, whichis reddish, and distinguish'd with white veins, and full of flints and hardlumps. Then they put near the places, which they will digge, a close andeven Earth; and to it they carry those Earths, they have digg'd out of theMine, and gently spread it abroad, and leave it exposed to the Sun for twodays. Then being dryed enough they beat it, and sifting this Earth, theyfind the Diamonds in ashes of Flints, in which Nature hath set them. Herehe adds, that the King of that Country farms out these Diamond-Mines for600000. Crowns _per annum_, reserving to himself the right of all theDiamonds, that exceed ten _Carats_ in weight. There are Diamonds, thatmount to 35. And 40. _Carats_. And this is the great Treasure of thatPrince. 2. That the most esteemed fruit in those parts; the _Durion_ (of thebigness and shape of an ordinary _Melon_) has a very unpleasing and unevenuntollerable smell, like to that of a rotten _Apple_. 3. That _Rice_ prospers most in waterish grounds; and that the fields, where it grows best, resembles rather to Marshes, than to any ploughedSoyle: Yea, that that Grain has the force, though 6. Or 7. Foot water standover it, to shoot its Stalk above it; and that the Stem, which bears it, rises and grows proportionably to the height of the water, that drowns thefield. 4. That the way of keeping ones self harmless from a wild _Elephant_, whenhe runs directly upon one, is, to hold something to him; as a Hat, a Coat, a piece of Linnen, which he seises on with his Trunk; and playes with it, as if he were pleased with this apparent homage, done to him; and so passeson. If he be in a rage, that then the only remedy is, to turn incessantlybehind him to the left side, in regard that naturally (_saith this Author_)he never turns himself that way, but to the right: And the time, there isto turn, because of the Beasts unweildiness, affords leisure enough toclimbe up some high Tree, or to mount some steep ground: all which if itfail, by holding always his tail, and turning with him, the Animal will betired, and give opportunity to escape. * * * * * _London_, Printed by _T. R. _ for _John Martin_, Printer to the _RoyalSociety_, and are to be sold at the _Bell_ a little without _Temple-Bar_. {329} * * * * * _Numb. _ 19. PHILOSOPHICAL_TRANSACTIONS. _ * * * * * _Munday_, _November_ 19. 1666. * * * * * The Contents. _An Addition to the Instances of _Petrification_, formerly enumerated. Articles of _Inquiries_ concerning _Mines_; as, to the neighbouring Country about them; the Soyl where they are; the Signes of them; the Structure and other particulars belonging to the Mines themselves; the Nature and Circumstances of _Ore_; and the Reduction of _Ore_ into _Metal_. Promiscuous _Inquiries_ formerly recommended to Monsieur _Heuelius_, particularly about _Cold_; together with his own, and his Correspondents _Answer_ to some of them. The success of the Experiment of Transfusing the Blood of one Animal into another. _ * * * * * _An Addition to the _Instances_ of _Petrification_, enumerated in the lastof these _Papers_. _ _This _Instance_ was some while since communicated to the _Royal Society_ by that Ingenious Gentleman Mr. _Philip Packer_, a worthy Member of that Body; in these words;_ On a Bank in a Close of Mr. _Purefoy_, neer his house, call'd _Wadley_, amile from _Farrington_ in _Berks_, there grows an _Elme_, which hath nowlost the top, and is grown hollow, containing neer a Tun of Timber. Fromthe But of the same Tree, one of the spreading Clawes having been formerlycut off with an Axe, that part of the But, from whence the same wassever'd, being about 1½ foot above ground, and inward within the trunk{330} of the Tree, hath contracted a petrfied Crust, about the thickness ofa _shilling_, all over the woody part within the Bark; the Marks of the Axealso remaining very conspicuous, with this petrified crust upon it. By whatmeans it should thus happen, cannot well be conceived, in regard there isno water neer it; the part, above the ground and out of the weather; theTree yet growing: unless being cut at some season, when the sap wasflowing, the owsing of the sap might become petrified by the Air, and theTree grow rotten and hollow inward since that time; which how long since, is not known. A piece of that part cut, was presented, together with this Account, to thesaid _Society_, for their _Repository_. * * * * * _Articles of Inquiries touching _Mines_. _ What the Honourable _Robert Boyle_ gave the Reader cause to hope for, in_Numb_. 11. When he was pleased to impart those _General Heads_ for aNatural History of a Country, _there_ publish'd; He is not un-mindful toperform, by enlarging them as occasion serves, with _Particular_ and_Subordinate_ Inquiries. Here he gratifies the Curious with a considerableSet of Inquiries about _Mines_: which though unfinish'd, yet the_Publisher_, was instant to obtain their present Publication, to the end, that he might the more conveniently recommend them to several Forreignersof his Acquaintance, now ready to return to their several Countryes, whichhe understands to abound in Mines; and from the Curious Inhabitantswhereof, he expects to receive a good Accompt upon some at least of theseInquiries; which also by several of them have been earnestly desired, asInstructions, to direct them, what Particulars to inquire after upon thisSubject. These Quæries are reduced by the _Author_ to six Heads: The _first_, The neighbouring Country about the Mines. The _second_, The Soyl where the Mines are. The _third_, The Signs of Mines. The _fourth_, The Structure and other particulars belonging to the Minesthemselves. The _fifth_, The Nature and Circumstances of the Ore. The _sixth_, the Reduction of the Ore into Metal. {331} _QUÆRIES_ _About the first Title. _ 1. Whether the Country be Mountainous, Plain, or distinguish'd with Vales?And in case it be mountainous, what kind of Hills they are; whether high, or low, or indifferently elevated? Whether almost equal or very un-equal inheight? Whether fruitful or barren; cold or temperate; rocky or not; hollowor solid? Whether they run in ridges, or seem confusedly placed; and, ifthe former, what way the ridges run, North and South, &c. And whether theyrun any thing parallel to one another? 2. Whether the Country be barren or fruitful? And, if any way fruitful, what it produces, and what it most abounds with? 3. What Cattle it nourishes, and whether they have any such thing peculiarin point of bigness, colour, shape, longævity, fitness or unfitness to makegood meat, &c. As may be rather adscribed to the peculiar nature of theplace, than to the barrenness of the Soyl, or other manifest causes? 4. Whether the Natives, and other Inhabitants, live longer or shorter thanordinary? Whether they live more or less healthy? Whether they be subjectto any _Epidemical_ Diseases, that may very probably be imputed to theMines; and what these Diseases are; and what Remedies are found successful? 5. Whether the Country be, or be not furnish'd with Rivers, Brooks, Springs, and other Waters; and how these waters are conditioned? 6. Whether the Air be dry or moist; hot or cold; clear or foggy; thick orthin; heavy or light; and especially, whether the Weather be more or lessvariable than ordinarily; or whether it be subject to great and suddenchanges, that may probably be imputed to the Mineral and SubterraneousSteams; and what they are? {332} _About the second Title. _ 7. Whether the _Soyle_ that is neer the Surface of the Earth, be Stony;and, if it be, what kind of Stones it abounds with? Whether it be Clayie, Marley, Chalkye, &c. And, if it be of several kinds, how many they are; andby what properties they are distinguish'd? _About the third Title. _ 8. By what _Signs_ they know or guess, that there is a Mine in such aplace? 9. These Signs are _either_ upon the Surface of the Earth, _or beneath_ it. To the _former_ belong these _Quæries_. 10. Whether the Ground be made barren by Metalline or Mineral Effluviums? 11. Whether it be observed, that Trees and other greater Plants seem tohave their tops burnt, or other leaves or outsides discoloured? or whetherthere be any Plants, that do affect to grow over such Mines; and whether ithave been tryed, that other Plants, that would prosper in the adjacentplaces, will not be made to grow and thrive there? 12. Whether the Stones and Pebles, that are wash'd by the Brooks, Springs, or other Waters, have any colour'd substance left upon them; and if theyhave, of what colour, weight, &c. These adherences are? 13. Whether the Waters of the place proposed, do by their tast, smell, ponderousness, &c. Disclose themselves to contain Minerals? And, if theydo, what Minerals they or their residences, when they are evapourated away, do appear to abound with, or to participate of? 14. Whether _Snow_ will not lye, or _Frost_ continue so long, or _Dew_ begenerated or stay upon the ground in the place proposed, as on otherneighbouring grounds? 15. Whether the _Dew_ that falls on that ground, will discolour whiteLinnen or Woollen-Cloths, spred overnight on the {333} surface of theground, and employed to collect the Dew? And whether the _Rain_ that fallsthere, and may be supposed to come thither from elsewhere, will discoloursuch Clothes, or afford any residence of a Mineral Nature? 16. Whether the Place be more than ordinarily subject to Thunder andLightning, and to sudden Storms or Earthquakes; as likewise to NocturnalLights and fiery Meteors. 17. Whether Mists use to rise from Grounds stored with Minerals? What isobservable in them, and what Minerals they signify, and may be supposed tobe produced by? 18. Whether the _Virgula Divinatoria_ be used to find out the Veins ofproposed Mines; and, if it be, with what success? 19. What other Signs above ground afford probability of Mines, or Directionfor following a Vein over Hills, Valleys, Lakes, Rivers, &c. The _second_ sort of _Signs_ belonging to these _Quæries_, are such asfollow. 20. Whether there be any Clayes, Marles, or other Mineral Earths, yellow orliquid matters, that usually give notice of the Ore? And if there be morethan one, how and at what depths they are wont to lye respectively? Of whatthickness and consistence they are; and in what Order the Diggers meet withthem? 21. Whether there be any Stones or _Marchasites_ to be found neer, or notvery far from the surface of the ground, by which one may have ground toexpect a Mine? As is often observed in the Tin-Mines of _Cornwall_, overwhich such kind of Stones are divers times found lying above ground? 22. Whether all Stones of that kind do equally signify that Mine? And, ifnot, how the significant Stones are to be known, as by Colour, Bigness, Shape, Weight, Depth under ground, &c. 23. Whether there be any Earths of peculiar kinds, as to Colour, Consistence, &c. That indicate a Mine beneath or near them; and, if therebe, what they are, and what is their consecution, if they have any? 24. Whether Heat or Damps give any assurance or a probability of finding aMine? {334} 25. Whether Water of any kind, met with in Digging, especially at this orthat depth, do betoken a Mine? 26. Whether there be any Signs of the neerness of the Mine, and what theyare? 27. Whether there be any Signs of ones having miss'd the Mine, either bybeing past above, or beneath, or having left it on either hand; and whatthey are? 28. Whether there be any Signs not only of the distinct and determinatekind of Metals or Minerals; but of the Plenty and Goodness of the Vein; andwhat they are? 29. Whether there be any Signs of the depth of the Vein beneath the surfaceof the Earth; and what they are? 30. Whether there be any proper or peculiar Signs, that show it to behopeless, or at least unlikely, to find a Vein in the place where it isdigg'd for; and what those are? _About the fourth Title. _ 31. What is the depth of the Shaft or Groove (which though named in the_singular_ Number; the Questions about it are _generally_ applicable) tillyou come at the Vein or Ore? 32. Whether the Vein run or lye Horizontal, or dippe? And if it dippe, what_inclination_ it hath, how deep the lowest part lies; and consequently howmuch deeper than the uppermost? As also, what it's Flexures, if it haveany, are? And whether it runs directly _North_ or _South_, _East_ or_West_; or seem rather to have a Casual tendency, than any determinate oneby Nature? and how far it reaches in all? 33. What is the Wideness of the Groove at the Top, and elsewhere? Whetherthe Groove be perpendicular or crooked; and if crooked, after what manner, and with what distance it winds? 34. How the Groove is supported? What are the kinds, length, bigness, andway of placing the Timber, Poles, &c. That are employed to support it? Andhow long the Wood will last, without being spoyled with the subterraneousfumes and waters? and what wood lasts longest? {335} 35. What Air-shaft belongs to the Mine? Whether it be _single_, or morethan One? Of what breadth the Air-shaft is at the Orifice? Whether it beconvenient enough, or not? How neer it is placed to the Groove; and in whatposition? And if there be _several_ Air-shafts, what their Distances andscituation are in reference to the Groove, and to each other? Or how Air issupplied, if there be no Air-shafts? 36. Whether they meet with any Waters in the Mine? And, if they do, howcopious they are; at what depths they occur; how they are qualified; andwhat way they Spring, &c. 37. Whether they are constant or temporary? whether they increase ordiminish notably in Summer or Winter, or at any other time of the year; andif they do, at what season that is; how long it is wont to last; and theproportions of Increase and Decrease? 38. What Expedients and Engines are employed to free the Mines from Water?The materials, the parts, the bigness, the shapes, the coaptation; and, inshort, the whole structure, number, and way of applying the Instruments, that are made use off to free the Mines from Water? 39. What are the Conditions, Number, &c. Of the _Adits_? 40. Whether the Mine be troubled with _Damps_, and of what kind they are?whether they come often or seldom at any set time, or altogetherirregularly? what Signs fore-run them? what mischief they do? what remediesare the most successfully imployed against them, aswell in reference to theCleering of the Mine, as to the Preservation and Recovery of the Workmen? 41. What Methods the Mine-men use in following the Vein, and tracing theirpassages under ground (which they call _Plumming_ and _Dyalling_) accordingto the several exigencies? And whether they employ the Instruments, madewith the help of the Load-stone, the same way that is usual; and if not, wherein they differ in the use of the same Instruments; or what Instrumentsthey substitute in their place? 42. What ways they take to secure themselves from the uncertainty, incidentto the guidance of _Magnetick_ Needles from the _Iron-Stone_ or Ore, thatthey may meet with under ground? {336} (of which yet perhaps there is notso great danger, as one may imagine; as far as I could find by a Trial, Ipurposely made in a Groove, where I was sure, there wanted not Iron-Ore. )And what other wayes may be used to direct Miners without the help of aLoad-stone? 43. How the Miners deal with the Rocks and Sparrs, they often meet with, before they come at the Ore? Whether they use Fire to soften, calcine, orcrack them? How they employ it, and with what measure of success? 44. What wayes and cautions they use, to free the Mine and secure theWork-men from the inconveniencies and danger accruing from the use of muchfire in it? 45. What Instruments they use to break the Rock &c? And how thoseInstruments are conducive; and how long they last? 46. How the Mine-men work; whether naked or cloathed? And what Lights theyuse to work by; what materials they are made of, what measure of light theygive; how long they last; and by what wayes they are kept burning in thatthick and foggy air? 47. How Veins are follow'd, lost, and recover'd? And how several Minerswork on the same Vein? And what is the best way of getting all the Ore in aVein, and most conveniently? 48. How they convey out their Ore, and other things, that are to be carriedout of the Mine? Whether they do it in Baskets drawn up by Ropes, or uponMens backs; and if this last-named way; what kind of Vessels they use formatter, shape, and capacity? And whether the Work-men deliver them one toanother; or the same Work-men carry them all the way? And whether theDiggers descend and ascend by Ladders of Wood, or of Ropes, &c. _About the Fifth Title. _ 49. Whether the Ore runs in a Vein; or lie dispers'd in scatter'd pieces;or be divided partly into a Vein, and partly into loose masses; or like aWall between two Rocks, as it were in a Cleft; or be interspers'd in thefirm Rock, like speckled Marble? Or be found in _Grains_ like _Sand_ or_Gravel_; as store {337} of excellent _Tin_ is said to be found in someparts of _Cornwall_ at the Sides and in the Channels of running Waters, which they call . .. ; or whether the Ore be of a softer consistence, like_Earth_ or _Lome_, as there is Lead-ore in _Ireland_ holding store ofSilver, and Iron-ore in the North parts of _Scotland_ and elsewhere? Andwhat is observable in it as to Weight, Colour, Mixture, &c? 50. Whether any part of the Metal be found in the Mine perfect andcomplete? (As I have had presented me good valuable _Copper_, and pieces ofperfect _Lead_, that were taken up, the one at _Jamaica_, and the other byan acquaintance of mine, that took them out of the ground himself in _NewEngland_. ) 51. Whether the Mine affords any parcels of Metal, that seem to grow like_Plants_ (as I have sometimes seen Silver growing, as it seemed, out ofStone, or _Sparre_ almost like blades of Grass; as also great Grains of aMetal, which appear'd to me, and which those, that tryed some of it, affirmed to be Gold, abounding in a stony lump, that seem'd to consistchiefly of a peculiar kind of _Sparre_. ) 52. Whether the Vein lie near, or much beneath the surface of the Earth, and at what depth? 53. Whether the Vein have or have not any particular Concomitants, or Coats(if I may so call them;) and, if any, what they are, and in what order theylie? (As the Veins of _Lead-ore_, with us, have frequently annnext to thema Substance call'd _Sparre_, and next to that another, call'd _Caulk_. ) 54. Whether (besides these Coats) the Vein have belonging to it any other_Heterogeneous_ substance? (As in _Tin-mines_ we often find that yellowsubstance, which they call _Mundick_. ) 55. What are the principal Qualities of these Extraneous substances? (Asthat _Sparre _ is white, but transparent, almost like course Crystall, heavy, britle, easily divisible into flakes, &c. _Caulk_ is of a differenttexture, white, opacous, and like a Stone, but much more ponderous. _Mundick_ I have had of a fine golden colour; but, though it be affirm'd tohold no Metal; yet I found it in weight, and otherwise, to differ from_Marchasites_; and the Mine-men think it of a poisonous nature. ) {338} 56. Whether the Vein be inclosed every way in its Coats; or whether it onlylye between them? 57. Whether the Vein be every way of an uniform breadth, and thickness;and, if it be, what these Dimensions are; and if not, in what places itvaries, and in what measures? (The like Questions are to be made concerningthe _sparre_, _Caulk_, and other Teguments or mixtures of the Ore?) 58. Whether the Vein be un-interrupted, or in some places broken off; andwhether it be abruptly, or not; and whether it be by Vales, Brooks, Gullets, &c? 59. How wide the Interruptions are? what Signs, whereby to find the Veinagain? whether the ulteriour part or division of the Vein be of the sameNature, and hold on in the same Course, as to its tendency upwards ordownwards, or Horizontally, Norward, Southward, &c. With the Vein, fromwhich it is cut off? 60. Whether, in case the last end of the Vein be found, it terminateabruptly, or else end in some peculiar kind of Rock or Earth, which does, as it were, close or Seal it up, without leaving any crack or cranny, orotherwise? And whether the terminating part of the Vein tend upwards, downwards, or neither? And whether in the places, where the Vein isinterrupted, there be any peculiar Stone or Earth, that does, as it were, seal up the Extremity of it? 61. Whether it be observed; that the Ore in Tract of time may be brought toafford any Silver or Gold, which it doth not afford, or more than it wouldafford, if it were not so ripe? And whether it have been found, that theMetalline part of the Vein grows so, that some part of the Mine will affordOre or Metal in tract of time, that did not so before? And whether to thisMaturation of the Mine, the being exposed to the free Air be necessary; or, whether at least it conduce to the Acceleration of it; or otherwise? 62. Whether all the Ore, contained in the Mine, be of the self-same natureand goodness; and, if not, what are the differing kinds; and how to bediscriminated and estimated? 63. What is the fineness and goodness of the Ore, by which the Mine is wontto be estimated? And what are the marks and {339} characters, thatdistinguish one sort from another? 64. What proportion of Metal it affords? (As in our _Iron-mines_ 'tisobserved, that about three Tuns of Iron-stone will afford one Tun of Metal:And I have had _Lead-Ore_, which an Ingenious man, to whom I recommendedsuch Tryals, affirm'd to me to afford three parts in four of good Lead. ) 65. Whether the Ore be pure in its kind from other Metals, and, if not, ofwhat Metals it participates; and in what proportion? Which is especially tobe Inquired into, in case the Mine be of a _base_ metal, that holds a_noble_ metal: (As I have known it observ'd, that _Lead-Ore_, that is poorin its own metal; affords more Silver, than other; and I remember, that the_Ore_ lately mention'd, being rich in Lead, scarce afforded us upon the_Cuppel_, an Atome of Silver. And _Matthesius_ informs us, that a littleGold is not unfrequently found in _Iron-Ore_. And I have by me some Gold, that never endur'd the Fire, taken out of a Lump of Tin-Ore. ) _About the sixth Title. _ 66. What are the mechanick and prævious Operations, as Beating, Grinding, Washing, &c. That are used to separate the Ore from the HeterogeneousBodies, and prepare it for the Fire? Or whether the Ore requires no suchpreparation? (as it often happens in Lead, and sometimes in Iron, &c. ) 67. Whether _Mercury_ be made use off, to extract the nobler from the basermetals? (as is their practice in _Peru_, and other parts of the_West-Indies_. ) 68. Whether the leaving the Ore expos'd to the open Air and Rain for a goodwhile, be used as a Præparative? (as I have seen done in _Iron-stone_. ) 69. Whether the Burning and Beating of the Ore be used to prepare it forthe Furnace? (as is practised in _Iron_, and almost always in _Copper_:)And, in case they use it more than once, how often they do it; (for, _Copper-Ore_ is in some places washed 8. Or 10. Times, and in others, 12. Or 14. ) and with what circumstances; as, how long the Ignition lasts at atime, whether the Ore be suffer'd to cool of it self, or be quench'd?whether it be washed betwixt each Ignition? 70. What Flux-powders, and other ways they have to try {340} and examinethe goodness of the Ore in small quantities? 71. Whether, when they work in _great_, they use to melt the Ore with anyFlux or Additaments, or only by the force of the Fire, or in any waybetween both? (As throwing in of Charcoals when they melt Iron-stone doesnot only serve to feed the Fire, but perhaps by the _Alchaly_ of its Ashesto promote the fusior: so Lime-stone, &c. ) 72. What kind of Furnaces they use, to melt the Ore in? Whether they be allof one sort and bigness, or of differing? 73. What are, the Situation, Materials, Dimensions, Shape, Bigness, and inshort what is the whole structure and Contrivance of the Furnace? If therebe any thing peculiar and remarkable? What Tools are used in Smelting, their Figures, use, &c. And the whole manner of working? 74. What kinds of Fewel, and what quantities of it, are wont to be employedin the Furnace, within the compass of a day, or week? How much is put in ata time? How often it is renewed? And how much Ore in a determinate time, asa week or a day, is wont to be reduced to Metal? 75. In case an Additament be employed, what that is, and in what proportionit is added? Whether it be mingled with the Ore, before that be put intothe Fire, or cast in afterwards; and, if so, at what time, &c? 78. Whether the Ore be melted by a Wind, excited by the Fire it self; as inWind-ovens? Ore by the course of Waters? Or acuated by the blast ofBellows; and, if so, whether these Bellows be mov'd by a Wheel, turn'd byWater running under it, or falling on it? And what are, the Dimensions, Situation, &c. Of the Bellows? 79. What contrivance they have, to let or take out the Metal, that is infusion; and cast it into Barrs, Sows, Pigs, &c? 80. What Clay, Sand, or Mould they let it run or pour it through? And afterwhat manner they refrigerate it? 8l. Whether or no they do, either to facilitate the fusion, or to obtainthe more or better Metal, mingle differing sorts or degrees of Ore of thesame metal? (As in some places 'tis usual, to mingle poor and rich Ore; andat _Mendip_ they mix two or more of these differing kinds of _Lead-ore_that they call _Frim-ore_, _Steel-ore_, _Potern-ore_, &c. ) {341} 82. Whether or no, having once brought the Ore to fusion, they melt all theMetal it self, to have it the more pure? And, if they do, with whatcircumstances they make the fusion? 83. Whether they have any Signs, whereby to know whether the Fusion havebeen well or ill perform'd; and the Metal have obtain'd the perfection, tobe expected from such Ore, melted in such a Furnace? 84. Whether they observe any great difference in the goodness of the Metal, that first melts, from that of the rest of the Metal which comes afterwardsin the same or another operation? And whether the Rule holds constantly?(For, though they observe in _Tin-Mines_, the best Metal comes first, yetin the works of an Industrious friend of mine, he informs me, that the bestMetal comes last. ) 85. Whether the produced Metal be all of the same goodness? And if it be, how good it is in reference to the Metal of other Mines, or other parts ofthe same Mine or Vein? And if it be not, what differences are observ'dbetween the produced portions of Metal; and what disparity that amounts toin the price? 86. What are the Wayes of distinguishing them, and estimating theirgoodness? 87. Whether they do any thing to the Metal, after it is once brought toFusion, and, if need be, melt it over again, to give it a melioration? (Aswhen _Iron_ is refined, and turn'd into Steel;) And what distinct Furnaces, and peculiar Ways of ordering the Metals are employ'd to effect thisimprovement? With a full description of them and the Tools in allCircumstances, observ'd in the refining of Metals. 88. Whether in those places, where the Metal is melted, there be notelevated some Corpuscles, that stick to the upper parts of the Furnace, orBuilding? And, if there be, whether they be barely fuliginous andrecrementitious exhalations, or, at least in part, Metallin Flowers? (As inthe _Cornish_ Tin-mines, after some years they usually destroy the thatch'dHouses, where the Ore hath been melted, to get the stuff, that adhears tothe insides of the Roofs, out of which they melt store of excellent Tin. ) 89. Whether the Metal, being brought to fusion, affords {342} anyRecrements? (As _Iron-stone_ affords store of a dark Glass or Slagg) And, if it do, what those Recrements are? How they are separated from the Metal;and to what Uses they are employed? 90. Whether, after the Metal has been once melted, the remaining part ofthe Ore being exposed to the Air, will in tract of time be impregnated, orripen'd, so as to afford more Metal? (For, this is affirm'd to me of the_Cornish_ Tin-Ore; and what remained after the fusion of _Iron-ore_ in the_Forest of Dean_, is so rich in Metal, that a Tenant of mine in _Ireland_, though he had on the Land, he held from me, an Iron-Mine, found it lessprofit to work it, than to send cross the Sea to the _Forest of Dean_ forthis already us'd Ore, which having lain for some ages, since it was thrownaside in great heaps expos'd to the Air, he affirm'd to yield as well greatgreat store of Iron, as very good: though I somewhat doubt, whether this be_totally_ to be ascribed to the Aire, and length of time; or to the leavingof Metal in the Slaggs in old times, before great Furnaces were in use. ) * * * * * _Promiscuous Inquiries about Mines, from the same Author. _ 1. Whether the Territorie, that bears the Mine, abounds with no other Kindof Mineral in some distinct part of it? (As in _Kent_ near _Tunbridge_, onepart of the Country which is Hilly, abounds all along with _Iron-Mines_;the other, which is also Hilly, and divided from it but by a small Valley, abounds exceedingly (as the Diggers and Inhabitants told me upon the place)in _Quarry's_, which the Metallin-Country wants, but is quite destitute ofIron-stone. And so at _Mendip_, in one part of the Hill, I saw store of_Lead-Mines_, containing several Kinds of Ore of that Metal; another partof the Hill I found to be full of _Cole-pits_, which had some_Marchasites_, but no Metal; and in another place, _Iron-ore_, and mixtOres, which yet they did not think fit to work. ) 2. Whether the Air appear to be really cold in Summer, {343} and hot inWinter at the bottom of the Mines, by surer proofs than the Testimony ofour Touch? 3. Whether they ever meet with places and Stones actually very hot, as_Matthesius_ relates? And whether that spring not from the quenching of_Marchasites_? 4. Whether they find in the Mines any Mineral Gelly, such as the _German_Naturalists call _Ghur_? And whether in process of time it will harden intoa metal, or Mineral Concretion? 5. What are the Laws, Constitutions, and Customs, _Oeconomical_, _Political_, _Ethical_, that are receiv'd and practis'd among the Mine-men? 6. Whether the Diggers do ever really meet with any subterraneous _Demons_;and if they do, in what shape and manner they appear; what they portend;and what they do, &c? 7. Whether they observe in the Trees and other Plants, growing over or neerthe Mine, not only, (as hath been already intimated) that the Leaves areany whit gilded or silver'd by the ascending Mineral Exhalations, but also, that the Trees or other Plants are more solid and ponderous? And if theyhave not also some discernable Metalline or Mineral Concretes, to be metwithin the small Cavities and Pores of their substance? 8. Whether there be not Springs, and also greater Streams of Water neer theMine, that rise, and run their whole course under ground, without everappearing above it? 9. Whether the Subterraneous Springs do rise with any wind or determinatechange of weather? 10. How much heavier the _Atmosphere_ is at the bottom of the Mine, than atthe top? And whether Damps considerably increase the weight of it? 11. Whether they find any strange substances in the Mines, as Vessels, Anchors, Fishes inclos'd in Sparr or Metal, &c. ? {344} * * * * * __Promiscuous Inquiries_, chiefly about _Cold_, formerly sent andrecommended to Monsieur _Heuelius_; together with his Answer return'd tosome of them. _ A considerable piece of the grand Design of the Modern _Experimental_Philosophers being, to procure and accumulate Materials for a good NaturalHistory, whence to raise in progress of time a solid Structure ofPhilosophy; all possible Endevours are used in _England_, to send abroadand recommend to as many of Forreign parts, as there is opportunity, _Directions_ for searching into the Operations of Nature, and for observingwhat occurs therein, aswell as in Mechanical operations and practices. Several Heads of that kind have been already publish'd for this purpose inseveral of the former Tracts; to which, as we have added, in this, the_Quæries_ about _Mines_, so we shall subjoyn those, that were not longsince committed to the care of that Excellent Promoter of Astronomy andPhilosophy, Monsieur _Heuelius_, Consul of _Dantzick_; who demonstrates somuch zeal for the advancement of real knowledge, that he not only improvesand promotes it by his own Studies, but labours also to incite others to dothe like; having already warmed many of the Northern Climate, particularly_Poland_, _Prusse_, _Livonia_, _Sweden_ and _Denmark_, into a dispositionto be studious and active in inquiring after such particulars concerningPhilosophy, as are recommended from hence, and rendred them, very willingto employ themselves in things of that nature. _The Inquiries sent to _Dantzick_, are these;_ 1. What Signior _Burattini_ (an _Italian_ Gentleman, Master of the Mint tothe King of _Poland_, and reputed a great Master in the _Mechanicks_) hathperform'd in _Diopticks_? Whether at present he employs himself, as isrelated, in grinding a _Telescope_ of 120 foot long? And, if so, what wayhe means to make use {345} of, commodiously to handle a Tube of thatlength? 2. Whether the same have the Art (as has been written from _Paris_) to makesuch Glass, as is not at all inferiour to _Venice_-glass, and exceeds anyplate of Glass, hitherto made there, twice or thrice in bigness? 3. What is the way of making Pot-ashes in _Poland_? 4. What is to be observed about _Succinum_ or Amber? whether it be anExsudation of the Sea? whether it be seen to float upon the surface of theSea? whether it be soft, when 'tis first cast on shore? At what season ofthe year, and in what manner 'tis taken up, &c? 5. What is to be observ'd in the Digging of _Sal Gemmæ_ in _Poland_? whatis the Depth of the Mines, stored with this Salt? what their distance fromthe Sea, &c? 6. What truth there is in that Relation concerning Swallows being found inWinter under waters congealed, and reviving, if they be fish'd and held tothe fire? 7. Whether there be in the _Bodnick Bay_ a Whirl-pool, as is related to bein the Sea of _Norway_, which is commonly call'd the _Maal-stroom_? Andwhether there be any Signs, that speak the communication of those Gulphs bysubterraneous passages; as the Jesuit _Kircher_ affirms in his _MundusSubterraneus_ T. 1. P. 146? 8. To what depth the Cold in those parts peirces the Earth and Water? 9. Whether their Watches go slower by the intense cold? 10. Whether their Oyls in hard frosts are turn'd into true, that is, hardand britle, Ice? 11. Whether they can freeze there a strong Brine of Bay-Salt; and a strongDecoction of _Sal Gemmæ_, or Soot; or a strong Solution of _Salt_ of_Tartar_, or of _Sugar_ of _Lead_? 12. Whether they can congeal meer _Blood_, all the serous part thereofbeing sever'd? Item, _Canary_ Wine; the _Lixiviums_ of Soap-boylers, andsuch as are prepared of other Salts; as also, the Spirits extracted out ofSalts, as Spirit of _Vitriol_, _Nitre_, &c? 13. Whether an intense and lasting Frost makes any alteration in_Quick-silver_, exposed very shallow in a flat Vessel. 14. Whether the Purgative virtue of _Catharticks_ be increased or lessened, or even totally destroy'd by a strong and continued Cold? {346} 15. Whether Harts-horn thaw'd, and such like substances, using the samemethod of Distilling, yield the same quantity of Liquor, which they use toyield, when not frozen? 16. What Cold operates in the Fermentation of Liquors? 17. Whether Birds and Wilde Beasts grow white there in Winter, and recovertheir native colour in Summer? 18. Whether Colours may be concentred by a sharp cold? _E. G. _ A strongDecoction of Cocheneel in a fit Glass? 19. Whether the _Electrical_ virtue of _Amber_, and the _Attractive_ and_Directive_ force of the _Magnet_, be changed by a vehement Cold? 20. Whether pieces of Iron and Steel, even thick ones, be made britle byintense frosts; and therefore Smiths are obliged for prevention, to givetheir Iron and Steel-tools a softer temper? 21. Whether accurate Observations evince, that all Fishes dye in frozenWaters, if the Ice be not broken? Where it is to be diligently inquiredinto, whether the Cold it self, or the want of changing or ventilating thewater, or the privation of Air, be the cause of the death of Fishes? 22. Whether any Physicians or Anatomists have inquired, by freezing todeath some Animals (as Rabits, Pullets, Dogs, Cats, &c. ) after what mannerit is, that Intense Cold kills men? whether they have found any Ice in theInner parts; and if so, in which of them; Whether in the Ventricles of theBrain and Heart; and in the greater Vessels? _These were the Queries_ recommended about a Twelve-month ago. Monsieur_Heuelius_ in a late Letter of his, accompanied with several papers fromothers, returns this Accompt. The Inquiries you proposed to me, I did impart to several of my Learnedfriends: But hitherto I have attained an Answer but to few particulars. Among the rest you'l find a Letter of the Learned _Johannes Schefferus_, Professor in the _Swedish_ University at _Vpsall_, wherein he discourseshandsomly of several things, being ready to entertain a Literary Commercewith you about such matters. Touching _Amber_, I am almost of the same mindwith him, that it is a kind of _Fossil Pitch_ or _Bitumen_, seeing it isnot only found on the Shore of the _Borussian_ Sea, but also digg'd up insubterraneous places, some _German_ miles distant from the {347} and thatnot only in Sandy, but also in other Hills of firmer Earth; of which I haveseen my self pretty big pieces. Concerning _Swallows_, I have frequentlyheard Fisher-men affirm, that they have here often fish'd them out of theLakes, in the Winter; but I never have seen it my self. Whilst I am writingthis, I receive Letters out of _Denmark_, advertising me, that those twoLearned men, _Thomas_ and _Erasmus Bartholin_, do intend shortly to answerthe same _Quæries_. Next Winter, if God vouchsafe me life and health, Ipurpose to make a Journey to _Konigs-berg_, where I hope to learn manythings, especially about _Amber_. _Thus far in answer to those Inquiries for the present. _ To this he subjoyns other things, no less fit to be communicated to theCurious, in these words; The Books you have sent me over sea, I have not yet received: I wish, theywere all translated into Latin; for I have not _English_ enough, tounderstand all particulars perfectly. For the rest, you have obliged me, bycommunicating the Observations of the last _Eclipse_ of the _Sun_, aswellthose made in _England_, as those of _Paris_ and _Madrid_. That I mayrequite you in some measure, I send you my Observations both of _that_, andthe _Moons_ last _Eclipse_. In the _Sun's Eclipse_, this is chieflyobservable, That the _Semidiameter_ of the _Moon_ from the very beginning, to about 5. Or 6. Digits of the increasing _Phasis_ was much less than the_Rudolphin_ Account imports. For it was then almost equal to the_Semidiameter_ of the _Sun_: but, after the greatest Obscuration, when Iagain contemplated the _Moons Semidiameter_, I found it 8" or 9" biggerthan that of the _Sun_; so that the _Semidiameter_ of the _Moon_ was notalways, during this Eclipse, constant to it self. It will therefore beworth while, to be hereafter more diligent and curious in this particular, and accurately to observe in the _Phasis_ of each _Digit_ the _Proportion_of the _Semidiameters_ of both Luminaries; to the end, that _first_ it maybe made manifest, Whether in all the _Eclipses_ of the _Sun_, or in someonly, that variation happens; _next_, that the Causes of such a_Phænomenon_ may be diligently inquired into. Of this Variation, theExcellent _Ismael Bullialdus_ hath also observed something at _Paris_. Forhe has written to me, That in the same Eclipse the _Semidiam. _ of the _Sun_to the _Semid. _ of the _Moon_ was, as 16'. 9". To 16'. 22"; but that inanother {348} _Phasis_ of 6 _digits_, the Semidiameters appear'd equal. These my Observations, if you think them worthy, you may communicate toother Mathematicians. The last year 1665. _July_ 27. (_st. N. _) the_Tables_ did also indicate an Eclipse of the _Moon_: but though the Skyhere was very cleer, yet the Moon was not at all obscured by the _trueshadow_, but entred only a little into the _Penumbra_, wherein it continued50'. The beginning of its touching the _Penumbra_ did then almost happen, when _Aquila_ was elevated 36° 18'; which is an Example worthy to be noted. I have many Observations of the _Eclipses_ of former years by me, which Icould not yet make publick, by reason of the multitude of my business, which do almost over-whelm me. The Eclipse of the Moon of this Year 1666. _June_ 16. (_st. N. _) was observed from a Hill neer my Garden, to the end, that we might see both together the _Suns setting_, and the _Moon rising_. But I was disappointed of my hopes: For very thick Exhalations, besiegingthe _Horizon_, where the Moon was to rise, unto 2°. 30', hindred me fromseeing the _Moon rise_, in the Article of the _setting_ of the _Sun_. Wherefore the first _Phasis_ of 1. _dig_. 45'. Did not appear but in the_Moons Altitude_ of 2°. 30'; when the greatest Obscuration was alreadypast. The _End_ fell out hor. 9. 27'. About 128° from the _Zenith_Westward. [Sidenote: * A Letter, written since from _Paris_, advertises, that some ofthe Curious there have received one of these Glasses of _Sr. Burattini_, and do esteem it to be good without mentioning the Dimension of it: whichyet is look'd for by the next. ] I am very glad to understand, that you have so good _Telescopes_, as tomake such considerable Observations in _Jupiter_ and _Mars_, as you havelately done in _England_. I have no leasure now, by reason of theObservations of the Fixt Stars, which I now almost constantly am employ'dabout, to do any thing in the advancing of _Telescopes_. I am obliged tofinish the _Catalogue_ of the _Fixt Stars_; having mean while thecontentment to find, that many excellent persons labour about theImprovement of _Optick Glasses_. If I could get a good one of those of 60. Foot, you mention, at a reasonable rate, you would oblige me in sending meone; perhaps may I be so happy, as to make likewise some good discovery orother, by the help thereof. In the mean time, let me know, I pray, theDimensions of those Glasses, and how they are to be managed. The ingenious_Burattini_ has not yet finisht his _Telescope_; as soon {349} as he hath, I shall acquaint you with it. * Before I conclude, I must give notice tothe Lovers of _Astronomy_, that on the 24. Of _September_ (st. N) of thisyear, I have observ'd that _New Star_ in _Pectore Cygni_ (which from theyear 1662. Untill this time hath been almost altogether hid) not only withmy naked Eye, like a Star of the sixth or seventh Magnitude, but also witha very great _Sextant_. It is still in the very same place of the Heavens, where it was formerly from _A. _ 1601. To almost 1662. For, its Distancefrom _Scheat Pegasi_ hath been by me found 35°. 51'. 20". And from_Marcab_, 43°. 10'. 50"; which Distances (as I have found in my _Journal_)are altogether equal to those, which I observ'd _A. _ 1658. The 1. Of_November_. For the Distance from _Scheat_ at that time was 35°. 51'. 20". And from _Marcab_, 43°. 10'. 25": where that former from _Scheat_ exactlyanswers to the recent; and that from _Marcab_, 'tis true, differs in a veryfew _Seconds_, but that disparity is of no moment, since it only proceededfrom thence, that this _New Star_ is not yet so distinctly to be seen, asat that time, when it was of the _third Magnitude_. It is thereforecertain, that it is the self same Star, which _Kepler_ did first see _A. _1601. And continued untill _A. _ 1662. But whether in time it will growbigger and bigger, or be lost again, time will shew. He that will observethis Star, must take care, lest he mistake those three more _Southern_ones, of the _Sixth Magnitude_, and now in a manner somewhat brighter(though not extant on the _Globe_) than the _New Star_ in _Collo Cygni_. The highest of those three, is distant from _Scheat Pegasi_ 36°. 25'. 45";the middlemost from the same, 37°. 25'. 20". And the lowest, 38°. 4'. 30". Farewell, and assure the Most Illustrious _Royal Society_ of my humblestServices. _So far Monsieur Heuelius_, whose accurate Calcul. Of the _Solar Eclipses_Duration, Quantity, &c. Is intended to be fully represented the next Month, since it could not be conveniently done this time. The _annexed_ Papersfollow. _One_ is from Monsieur _Joh. Schefferus_, to this purpose. 1. That he is confident, the _Royal Society_ of _England_ will do much goodfor the advancement of usefull Knowledge. {350} 2. That he conceives _Amber_ to be a kind of _Fossil Pitch_, whole Veinslie at the bottom of the Sea; believing that it is hardned in tract oftime, and by the motion of the Sea cast on shore: _He adds_, that hithertoit hath been believed, not to be found but in _Borussia_; but he assures, that it is also found in _Sueden_, on the shores of the Isle _Biorkóó_, inthe Lake _Melero_, whose water is _sweet_. Of this, _he saith_, he hath afine piece by him, two inches large and thick, presented him by one, thathimself with his own hands had gathered it and several other pieces, on theshore of the said Island; affirming withall from the mouth of a Shepherd ofthat place, that it is thrown out by a strong Wind, bearing upon the shore. 3. That it is most certain, that _Swallows_ sink themselves towards Autumneinto Lakes, no otherwise than _Frogs_; and that many have assured him ofit, who had seen them drawn out with a Net together with Fishes, and put tothe fire, and thereby revived. 4. That 'tis also very true, that many _Animals_ there grow white inWinter, and recover their own Colour in Summer. That himself hath seen andhad _Hares_, which about the beginning of Winter and Spring were halfwhite, and half of their native colour: that in the midst of winter henever saw any but all white. That _Foxes_ also are white in Winter; and_Squirrels_ grayish, mixt of dark and white colour. 5. That 'tis known there generally, that _Fishes_ are killed, by reason ofthe Ice not being broken: but _first_, in ponds only or narrow Lakes;_next_, in such Lakes only, where the Ice is pretty thick; for, where 'tisthin, they dye not so easily. _Lastly_, that those Fishes that lie in slimyor clayie ground, dye not so soon as others. But, _he adds_, that even ingreat Lakes, when 'tis a very bitter Frost, Ice is wont to be broken, either by the force of the Waves, or of the Imprisoned Vapors, raised bythe agitation of the Water, and then bursting out with an impetuosity;witness the noise made by the rupture of the Ice through the whole lengthof such Lakes, which _he affirms_ to be not less terrible than if many gunswent off together. Whereby it falls out, that Fishes are seldom found deadin great Lakes. 6. That neither Oyle, nor a strong Brine of Bay-Salt, is truly {351}congeal'd into Ice, in those parts, _Viz. _ at _Upsall_ in _Sueden_. 7. That the Frost pierces into the Earth, two Cubits or _Swedish_ Ells; andwhat moisture is found in it, is white, like Ice: That Waters, if standing, freeze to a greater depth, even to three such Ells or more; but those thathave a Current, less: That rapid Rivers freeze not at all; nor ever-bublingSprings; and that these latter seem even to be warmer in Winter, thanSummer. _So far this Observer_; who likewise offers his Services in giving ananswer to the remaining _Queries_, and in entertaining a commerce in suchother Philosophical matters, as he is conversant in. _Another_ Paper written by Monsieur _Febre_, chief Secretary to Prince_Ratzivil_, contains these particulars; 1. That the College of the Learned in _Borussia_, finds it not so easie toresolve all those _Queries_ sent from _England_ to M. _Heuelius:_ but yetthat they will try what may be done upon it. 2. That as for himself, he can assure from his own Experience concerningthe Effects of Cold; _First_, That in the War against the _Muscovites_ and_Cosacks_, _A. _ 1655. In _January_, in _White Russia_, at the Siege of_Biskow_, 30. Leagues from _Smolensko_, and three from _Morhilo_, near theRiver _Boristhenes_, when they had Quarter in a Village call'd _Bikau_, they were seized on with such a Frost, that all their Provisions of_Spanish_ Wines or _Petersimen_, and _Beere_, were in one Night frozen uponthe Sleds, notwithstanding they were cover'd with Straw; in so much, thatwhen next morning they would have drawn of those Liquors, they found alldry, and were constrain'd to carry them into a Stove, to thaw them; whichthey could not do in two whole days, and were obliged to break the Vessels, and put pieces of the Icy Wine into Kettles to thaw them over the Fire, forDrink: That they asked not for a Draught, but a _Morsel_ of Wine or Beer:That their Horses had no better cheer than themselves, as to matter ofDrink; the Pond of the Village being so thoroughly frozen, that there wasbut very little Water left between the Ice and the bottom of the Pool;whereby the poor Beasts were forced to drink with great reverence, kneelingon the forefeet to thrust their heads into the holes, made for them in theIce, and to suck thence some drops of Water; and that, if they had not hadSnow to eat, there would have dyed a far greater {352} number of them, thanthere did. Moreover, that he observed, that the _Hungarian Wine_, of whichthey had a Tun, resisted the Cold better, than the _Peter Simen_; for itwas not so much frozen; unless it be, that the Butler had more care ofthat, than the rest, by transporting it sooner into the Stove, when hefound the excess of Cold. Again, that one presenting him in the March withsome _Aqua-vitæ_, the Scrue of the Flagon, put to his Mouth, stuck so closeto his Lips, that he could not draw it off, without drawing bloud, In a _third_ Paper, I find these particulars from the same M. _Febre_. 1. That a considerable person, one Dr. _Becker_, a great Lover of CuriousInquiries, has given him hopes to entertain this Philosophical Commerce. 2. That he hath seen men dye in _Poland_ and _Lithuania_ both of _Heat_ and_Cold_. And _first_, that _A. _ 1653. In _July_, being with this presentKing of _Poland_ in march from _Leopoli_ to the Camp of _Glignani_, it wasso furiously hot that day of their march, that it caused such an alterationin that Regiment of Foot, which was the Kings Guard, marching most of thembare-foot upon Sands, that more than an hundred of them fell downaltogether disabled, whereof a dozen dyed out-right, without any otherSickness. _Secondly_, as to the Cold, that the frost was so bitter, that 3Souldiers dyed of it, _A. _ 1665. The 2. Of _January_, in passing a longDitch: besides, that divers persons lost some of their Lims. * * * * * _The Success of the Experiment of Transfusing the Bloud of one Animal intoanother. _ This experiment, hitherto look'd upon to be of an almost unsurmountabledifficulty, hath been of late very successfully perform'd not only at_Oxford_, by the directions of that expert Anatomist Dr. _Lower_, but alsoin _London_, by order of the _R. Society_, at their publick meeting in_Gresham Colledge:_ the Description of the particulars whereof, and the_Method_ of Operation, is referred to the next Opportunity. * * * * * _Errata_ to be corrected in Number 18. Pag. 311. Line 18. Read _marked_. P. 312. L. 35. R. _Sines_. Ib. L. Penult. _Sines_. P. 313. L. 13. R. _Sines_. P. 316. L. 26. R. _that_ for _if_. * * * * * _London_, Printed for _John Crook_ neer the _Blew-Anchor_ in _Duck-lane_;and _Mose Pits_ at the _White-Hart_ in _Little-Britain_. {353} * * * * * _Numb. _ 20. PHILOSOPHICAL_TRANSACTIONS. _ * * * * * _Munday_, _December_ 17. 1666. * * * * * The Contents. _The Method observed in _Transfusing the Bloud out of one live Animal into another_: And how this Experiment is like to be improved. Some Considerations concerning the same. An Accompt of some Sanative Waters in _Herefordshire_. A farther Accompt of the _Vitriolate_ Water mention'd _Numb. 18_. Together with some other particulars touching Waters. Inquiries for _Turky_. An Observation about Optick Glasses made of Rock-Crystal, communicated from _Italy_. A Relation of the Use of the Grain of _Kermes_ for _Coloration_, from _France_. An Accompt of some Books lately publisht, _vid. 1_. PINAX Rerum Naturalium BRITANNICARUM, continens VEGETABILIA, ANIMALIA & Fossilia ANGLIÆ, inchoatus; Auth. _Christophoro Merret_, M. D. _2_. PLACITA PHYLOSOPHICA _Guarini. 3_. GUSTUS ORGANUM per _Laurentium Bellini_ deprehensum. _ * * * * * The Method observed in _Transfusing the Bloud of one Animal into another. _ This Method was promised in the last of these Papers. It was firstpracticed by Dr. _Lower_ in _Oxford_, and by him communicated to theHonourable _Robert Boyl_, who imparted it to the _Royal Society_, asfollows; First, Take up the _Carotidal_ Artery of the Dog or other Animal, whoseBloud is to be transfused into another of the {354} same or a differentkind, and separate it from the Nerve of the _Eighth pair_, and lay it bareabove an inch. Then make a strong Ligature on the _upper_ part of theArterie, not to be untied again: but an inch below, _videl. _ towards theHeart, make another Ligature of a _running_ knot, which may be loosen'd orfastned as there shall be occasion. Having made these two knots, draw twothreds under the Artery between the Ligatures; and then open the Artery, and put in a Quil, and tie the Artery upon the Quill very fast by those twothreds, and stop the Quill with a stick. After this, make bare the_Jugular_ Vein in the other Dog about an inch and a half long; and at eachend make a Ligature with a running knot, and in the space betwixt the tworunning knots drawn under the Vein two threds, as in the other: then makean Incision in the Vein, and put into it two Quills, one into the_descendent_ part of the Vein, to receive the bloud from the other Dog andcarry it to the Heart; and the other Quill put into the other part of the_Jugular_ Vein, which comes from the Head (out of which, the second Dogsown bloud must run into Dishes. ) These two Quills being put in and tiedfast, stop them with a stick, till there be occasion to open them. All things being thus prepar'd, the Dogs on their sides towards one anotherso conveniently, that the Quill may go into each other, (for the Dogs neckscannot be brought so near, but that you must put two or three severalQuills more into the first two, to convey the bloud from one to another. )After that unstop the Quill that goes down into the first Dog's _Jugular_Vein, and the other Quill coming out of the other Dog's Artery; and by thehelp of two or three other Quills, put into each other, according as thereshall be occasion, insert them into one another. Then flip the runningknots, and immediatly the bloud runs through the Quills, as through anArtery, very impetuosly. And immediately, as the bloud runs into the Dog, unstop the other Quill, coming out of the _upper_ part of his _Jugular_Vein (a Ligature being first made about his Neck, or else his other_Jugular_ Vein being compress'd by ones Finger;) and let his own bloud runout at the same time into Dishes (yet not constantly, but according as youperceive him able to bear it) {355} till the other Dog begin to cry, andfaint, and fall into Convulsions, and at last dye by his side. Then take out both the Quills out of the Dogs _Jugular_ Vein, and tye therunning knot fast, and cut the Vein asunder, (which you may doe without anyharm to the Dog, one _Jugular_ Vein being sufficient to convey all thebloud from the Head and upper parts, by reason of a large _Anatomosis_, whereby both the _Jugular_ Veins meet about the _Larinx_. ) This done, sowup the skin and dis-miss him, and the Dog will leap from the Table andshake himself and run away, as if nothing ailed him. And this I have tryed several times, before several in the _Universities_, but never yet upon more than one Dog at a time, for want of leisure, andconvenient supplyes of several Dogs at once. But when I return, I doubt notbut to give you a fuller account, not only by bleeding several Dogs intoone, but several other creatures into one another, as you did propose tome, before you left _Oxford_; which will be very easie to perform; and willafford many pleasant and perhaps not unuseful Experiments. But because there are many Circumstances necessary to be observ'd in theperforming of this Experiment, and that you may better direct any one todoe it, without any danger of killing the other Dog, that is to receive theothers bloud, I will mention two or three. _First_, that you fasten the Dogs at such a convenient distance, that theVein nor Artery be not stretched; for then, being contracted, they will notadmit or convey so much bloud. _Secondly_, that you constantly observe the Pulse beyond the Quill in theDogs _Jugular_ Vein (which it acquires from the impulse of the _Arterious_bloud:) For if that fails, then 'tis a sign the Quil is stopt by somecongealed bloud, so that you must draw out the _Arterial_ Quill from theother, and with a _Probe_ open the passage again in both of them, that thebloud may have its free course again. For, this must be expected, when theDog, that bleeds into the other, hath lost much bloud, his heart will beatvery faintly, and then the impulse {356} of bloud being weaker, it will beapt to congeal the sooner, so that at the latter end of the work you mustdraw out the Quill ofter, and clear the passage; if the Dog befaint-hearted, as many are, though some stout fierce Dogs will bleed freelyand uninterruptedly, till they are convuls'd and dye. But to prevent thistrouble, and make the experiment certain, you must bleed a great Dog into alittle one, or a _Mastive_ into a _Curr_, as I once try'd, and the littleDog bled out at least double the quantity of his own bloud, and left the_Mastive_ dead upon the Table, and after he was untyed, he ran away andshak'd himself, as if he had been only thrown into water. Or else you mayget three or four several Dogs prepared in the same manner; and when onebegins to fail and leave off bleeding, administer another, and I amconfident one Dog will receive all their bloud, (and perhaps more) as longas it runs freely, till they are left almost dead by turns: provided thatyou let out the bloud proportionably, as you let it goe into the Dog, thatis to live. _Thirdly_, I suppose the Dog that is to bleed out into dishes will endureit the better, if the Dogs that are to be administred to supply his bloud, be of near an equal age, and fed alike the day before, that both theirblouds may be of a neer strength and temper. There are many things I have observed upon bleeding Dogs to death, which Ihave seen since your departure from _Oxford_, whereof I shall give you arelation hereafter; in the mean time since you were pleased to mention itto the _Royal Society_, with a promise to give them an account of thisexperiment, I could not but take the first opportunity to clear you fromthat obligation, &c. _So far this Letter;_ the prescriptions whereof having been carefullyobserv'd by those who were imployed to make the Experiment, have hithertobeen attended with good success; and that not only upon Animals of the same_Species_ (as two Dogs first, and then two Sheep) but also upon some ofvery differing _Species_ (as a Sheep and a Dog; the former _Emitting_, theother _Receiving_) _Note_ only, that instead of a Quill, a small crooked thin {357} Pipe ofSilver or Brass, so slender that the one end may enter into a Quill, andhaving at the other end, that is to enter into the Vein and Arterie, asmall knob, for the better fastening them to it with a thread, will be muchfitter than a strait Pipe or Quill, for this Operation: for so they aremuch more easie to be managed. 'Tis intended, that these tryals shall be prosecuted to the utmost varietythe subject will bear: As by exchanging the bloud of Old and Young, Sickand Healthy, Hot and Cold, Fierce and Fearful, Lame and Wild Animals, &c. , and, that not only the same, but also of differing kinds. For which end, and to improve this noble Experiment, either for knowledge, or use, orboth, some Ingenious men have already proposed considerable tryals andInquiries; of which perhaps an account will be given hereafter. For thepresent we shall only subjoyn some. _Considerations about this kind of Experiments. _ 1. It may be consider'd in them, that the bloud of the _Emittent_ Animal, may after a few minuts of time, by its circulation, mix and run out withthat of the _Recipient_. Wherefore to be assured in these Tryals, that allthe bloud of the _Recipient_ is run out, and none left in him but theadventitious bloud of the _Emittent_, two or three or more Animals (whichwas also hinted in the _method_ above) may be prepared and administred, tobleed them all out into one. 2. It seems not irrational to guess afore hand, that the exchange of bloudwill not alter the nature or disposition of the Animals, upon which itshall be practised; though it may be thought worth while for satisfactionand certainty, to determine that point by Experiments. The case ofexchanging the bloud of Animals seems not like that of _Graffing_, wherethe _Cyons_ turns the Sap of the _Stock_, graffed upon, into its nature;the _Fibres_ of the Cyons so straining the juice, which passes from thestem to it, as thereby to change it into that of the Cyons, whereas in thistransfusion there seems to be no such {358} Percolation of the bloud ofAnimals, whereby that of the one should be changed into the nature of theother. 3. The most probable use of this Experiment may be conjectured to be thatone Animal may live with the bloud of another; and consequently, that thoseAnimals, that want bloud, or have corrupt bloud, may be supplyed from otherwith a sufficient quantity, and of such as is good, provided theTransfusion be often repeated, by reason of the quick expence that is madeof the bloud. * * * * * Note. _In the last _Transactions_ was also promised an Accompt by the next, ofMonsieur _Hevelius_ his accurate Calcul. Of the late _Solar Eclipses_, Duration, Quantity, &c. But this being to be accompanyed with _Scheme_, the_Graving_ whereof met with a disappointment, it must be still referred toanother Opportunity. _ * * * * * _An Accompt of some Sanative-waters in _Herefordshire_. _ This account was communicated by Dr. _B. _ in these words. There are two Springs in _Herefordshire_, whereof one is within a Bolt, orat least Bow-shoot of the top of the near adjoyning loftie Hill of_Malvern_, and at great distance from the Foot of the Hill; and hath had along and old fame for healing of eyes. When I was for some years molestedwith Tetters on the back of one and sometimes of both my hands, notwithstanding all endeavors of my very friendly and skilful Physitians Ihad speedy healing from a neighbouring Spring of far less fame. Yet thisSpring healed very old and Ulcerous sores on the Legs of a poor Fellow, which had been poyson'd by Irons in the Gaol, after other Chirurgery hadbeen hopeless. And by many tryals upon my hands, and the Tetters; I wasperswaded, that in long droughts, and lasting dry Frosts, those waters weremore effectually and more speedily healing, than at other times. And not toomit this circumstance, I did hold this water in my mouth, till it waswarm, perchance somewhat intermingled with fasting Spittle, {359} and sodropping it upon the Tetter, I there could see it immediately gather a verythin skin upon the raw flesh, not unlike that which is seen to gather uponMilk over a gentle fire. This skin would have small holes in it, throughwhich a moisture did issue in small drops, which being wip'd away, and thewater continued to be dropp'd warm out of the mouth, the holes woulddiminish, and at last be all quite healed up. For the _Eye-waters_, I conceived them more strongly tersive, and clearingthe Eyes; and they had a rough smartness, as if they carryed Sand or Gravelinto the Eye. I have known and try'd three or four healing Fountains of late discovery, or of no old fame that I could hear of. I did once put rich _Marle_ for some days in a vessel of water, to trywhether the water would acquire a healing vertue, but my Experiments wereinterrupted. I had in my thoughts many other ways of Tryal; which I mayresume hereafter. * * * * * _A farther Accompt of the _Vitriolate-water_, mention'd _Num. 18 p. 323_. Together with some other particulars touching waters. _ This comes from the same hand as follows; I formerly mentioned to you, that, if that Pool of Mr. _Phillip's_, whichseems to be of Vitriolate-water, were on my ground, I would drain it, andsearch the head of the Spring, pursuing the source, till I could welldiscern, through what lay of Earth or Gravel it does pass. Now I shall tellyou, that I have taken order for the further tryal of the said Water, byboiling a greater quantity in a Furnace, &c. But just as we were inreadiness for the tryal, a stream of Rain-water fell into the Pool, and sodiscourag'd us for the present. I have also taken a course to turn thefalling Waters aside, and to drain the Pool, that we may see, what theNative Springs (whether one or more) may be. Of which more hereafter. I wish (_so he goes on_) we had a full Accompt of our _Salt-Springs_ at_Droyt-wych_ near _Worcester_, and at _Nant-wych_ in _Cheshire_ (what otherSalt-Springs we have in _England_, I know not:) {360} It should beinquired, at what distance they are from the Seas, or from Salt-fluxes, from Hills, and how deep in the Vales? What the weight? Whether in droughtsor long Frosts the proportion of Salt or weight increaseth? Whether theEarth near the Springs, or in their passage hath any peculiar ferment, orproduceth a blackishness, if it rests, after it is well drained. * * * * * _Inquiries for _Turky_. _ Though many Relations and Descriptions of _Turky_ be extant in Print, yetthey leave in many a desire of a fuller information in the followingparticulars, lately drawn up, for the most part by Mr. _H. _ and recommendedto an Ingenious Gentleman, bound for that Country; and desired also to betaken notice of by others, that may have occasion to visit the same. [Sidenote: * _Rusma_ is a kind of Earth, used in _Turky_ to take awayhair. ] 1. In what part of _Turky_ the * _Rusma_ is to be found; and in whatquantity? Whether the _Turks_ employ it to any other Uses, besides that ofthe taking away of Hair? Whether here be differing kinds of it? How it isused to take of hair, and how to get store of it. 2. Whether the _Turks_ do not only take _Opium_ themselves for strength andcourage, but also give it to their Horses, Camels and Dromedaries, for thesame purpose, when they find them tired and faint in their travelling? Whatis the greatest _Dose_, any men are known to have taken of _Opium_? and howprepared? 3. What effects are observed from their use, not only of _Opium_ (alreadymention'd) but also of Coffee, Bathing, shaving their Heads, using Rice;and why they prefer that which grows not unless water'd, before Wheat, &c. 4. How their Damasco steel is made and temper'd? 5. What is their way of dressing and making Leather, which though thin andsupple, will hold out water? 6. What method they observe in breeding those excellent Horses, they are somuch famed for? 7. Whether they be so skilful in Poysoning, as it is said; and how theirPoysons are curable? {361} 8. How the _Armenians_ keep Meat fresh and sweet so long, as 'tis said theydo? 9. What Arts or Trades they have worth Learning? 10. Whether there be such a Tree about _Damascus_, call'd _Mouslat_, whichevery year about the Month of _December_ is cut down close by the root, andwithin four or five Months time shoots up again apace, bringing forthLeaves, Flowers, and Fruit also, and bearing but one Apple (an excellentFruit) at once? 11. Whether about _Reame_ in the Southern part of _Arabia Foelix_, there beGrapes without any grains? And whether the people in that Country live, many of them, to a hundred and twenty years, in good health? 12. Whether in _Candia_ there be no poysonous Creatures; and whether thoseSerpents, that are there, are without poyson? 13. Whether all Fruits, Herbs, Earth, Fountains, are naturally saltish inthe Isle of _Cyprus_? And whether those parts of this Isle, which abound in_Cyprus-trees_, are more or less healthful, than others? 14. What store of _Amianthus_ there is in _Cyprus_; and how they work it? 15. Whether _Mummies_ be found in the sands of _Arabia_, that are the dryedflesh of men buried in those sandy Deserts in travelling? And how theydiffer in their vertue from the Embalmed ones? 16. Whether the parts about the City of _Constantinople_ or _Asia Minor_, be as subject to Earth-quakes now, as they have been formerly? And whetherthe Eastern Winds do not Plague the said City with Mists, and cause thatinconstancy of Weather, it is said to be subject to? 17. Whether the Earth-quakes in _Zant_ and _Cephalonia_ be so frequent, asnow and then to happen nine or ten times a Month? And whether these Islesbe not very Cavernous? 18. What is the height of Mount _Caucasus_, its position, temper in itsseveral parts, &c. 19. With what declivity the Water runs out of the _Euxine-Sea_ into the_Propontis_? With what depth? And if the many Tides and Eddies, so famousby the name of the _Euripi_, have any certain Period? {362} 20. If in the _Euxine-Sea_ there can be found any sign of the _CaspianSeas_ emptying it self into it by a passage under ground? If there be anydifferent Colour, or Temper as to Heat or Cold; or any Current or Motion inthe Water, that may give light to it? 21. By what Inland passages they go to _China_; there being now a passagefor _Caravans_ throughout those places, that would formerly admit of noCorrespondence by reason of the Barbarisme of the Inhabitants? 22. Whether in the Aquæducts, they make, they line the inside with as goodPlaister, as the Ancients did? and how theirs is made? 23. To inquire after these excellent works of Antiquity, of which thatCountry is full, and which by the ignorant are not thought worth notice orpreservation? And particularly, what is the bigness and structure of theAquaeducts, made in several places about _Constantinople_ by _Solyman_ theMagnificent? &c. * * * * * _An Observation of Optick Glasses made of _Rock-Chrystal_. _ This is contained in a Letter of _Eustachio Divini_, Printed in _Italian_at _Rome_, as the _39. Journal des Scavans_ extracts it, _vid. _ [Sidenote: * It may be queried whether those were true Veins, or onlySuperficial Strictures, and slight scratches. ] Though it be commonly believed, that _Rock-Christal_ is not fit forOptick-Glasses, because there are many Veins in it; yet _Eustachio Divini_made one of it, which _he saith_ proved an excellent one, though full ofVeins. * * * * * * _An Accompt of the Use of the Grain of _Kermes_ for Coloration. _ This was communicated by the Ingenious Dr. _Croon_, as he received it fromone Monsieur _Verny_, a _French_ Apothecary at _Montpelier_; who havingdescribed the Grain of _Kermes_, to be an excrescence growing upon theWood, and often upon the {363} leaves of a Shrub, plentifull in_Languedock_, and gather'd in the end of _May_, and the beginning of_June_, full of a red Juyce; subjoyns two Uses, which that Grain hath, theone for _Medicine_, the other for _Dying of Wool_. Waving the _first_, notice shall only be taken here of the _latter_, vid. That, for _Dying_, they take the Grain of _Kermes_, when ripe, and spread it upon Linnen: Andat first, whilst it abounds most in moisture, 'tis turn'd twice or thrice aday, to prevent its Heating. And when there appears red powder amongst it, they separate it, passing it through a Searce; and then again spread abroadthe Grain upon Linnen, untill there be perceived the same redness of thepowder; and at the end, this red power appears _about_ and _on_ the surfaceof the Grain, which is still to be pass'd through a Searce, till it renderno more. And in the beginning, when the small red Grains are seen to move (as theywill do) they are sprinkled over with strong Vinegar, and rubb'd betweenones hands: afterwards little balls are form'd thereof, which are expos'dto the Sun to dry. If this red powder should be let alone, without pouring Vinegar or someother accid liquor upon it, out of every Grain thereof would be form'd alittle Fly, which would skip and fly up and down for a day or two, and atlast changing its colour, fall down quite dead, deprived of all thebitterness, the Grains, whence they are generated, had before. The Grain being altogether emptyed of its pulp or red powder, 'tis wash'din Wine, and then expos'd to the Sun Being well dryed, 'tis rubb'd in aSack to render it bright; and then 'tis put up in small Sacks, putting inthe midst, according to the quantity, the Grain has afforded, 10. Or 12. Pounds (for a _Quintal_) of the dust, which is the red powder, that cameout of it. And accordingly, as the Grain affords more or less of the saidpowder, Dyers buy more or less of it. 'Tis to be noted, That the first red powder, which appears, issues out ofthe Hole of the Grain, that is on the side, where the Grain adhered to thePlant. And that, which about the end appears sticking on the Grain, hathbeen alive in the husk, having pierced its covers though the hole, whenceit commonly issues, remains close as to the Eye. {364} * * * * * _An Account of Some Books lately published. _ 1. _PINAX Rerum Naturalium BRITANNICARUM, continens VEGETABILIA, ANIMALIA &FOSSILIA in hoc Insula reperta, inchoatus, Auth. _ Christophoro Merret, _Med. D. & utriusque_ Societatis Regiæ _socio. _ The Learned and Inquisitive Author of this Book, hath by his laudableexample of collecting together, what Natural things are to be found here in_England_, of all sorts (which he has done upon his own expences) given aninvitation to the curious in all parts of the world to attempt the like, thereby to establish the much desired and highly useful commerce among_Naturalists_, and to contribute every where to the composing of a genuineand full _History of Nature_. In the _Preface_ he intimates, that his stock does still encrease dayly;and that therefore the Reader may expect an _Appendix_ to this collection. In the Body of the Book, he enumerates all the _Species_, Alphabetically:And, as to _Vegetables_, he reckons up about 410 sorts; and gives their_Latine_ and _English_ Names, and the _Places_ and _Times_ of their growth:reducing them afterwards to certain _Classes_, hitherto used by _Botanick_Writers in their _Histories_ of _Plants_: Adding the _Etymology_ of theirGenerick Names, and a compendious _Register_ of the Time, _when_ and _howlong_ the _English_ Plants do shoot and flourish. As to _Animals_, he finds of them about 340 kinds in _England_, whereof the_fourfooted_ are about 50, _Birds_ 170, and _Fishes_ 120. _Insects_ areinnumerable, which yet he endeavours to enumerate, and to reduce to certain_Classes_; into which he also brings the three former kinds. Concerning _Fossils_, he _first_ takes notice of the _Metals_ found in_English_ Mines; as _Silver, Tin, Copper, Iron, Lead, Antimony_, and some_Gold_ extracted out of _Tin_. Next of the _Stones_, of which he findsabout 70 sorts; & amongst them, _Bristol Diamonds, Agates, Hyacinths, Emerods, Loadstones, Toad-stones_, (which last yet he affirms to be nothingbut the grinding-teeth of the {365} Fish _Lupus_) _Pearls, Corals, Marble, Alablaster, Emery:_ To which he adds the various kinds of _Coals_; as also_Bitumens, Turfs_ and _Jets_. And _thirdly_ of the various kinds of _Allam, Vitriol, Niter, Sea-salt, Pit-salt_. But _fourthly_ of the various_Earths_, of which he reckons up 15. Peculiar sorts (besides those thatserve for _Husbandry_, which are not easily numbred;) and amongst them, _Read-lead, Black-lead_ and _Fullers-earth_. He concludes all with mentioning the several _Meteors_ appearing in_England_; and the _Hot springs_; and _Medical Waters_; as also, the_Salin, Petrifying_, and some more unusual Springs: _Item, SubterraneousTrees, Subterraneous Rivers, Ebbings and Flowings of Wells_, &c. II. _PLACITA PHILOSOPHICA Guarini. _ The chief subject of this Treatise isNatural _Philosophy_; upon many important questions whereof it enlargeth, as those of the Motion of the Coelestial Bodies, of Light, of Meteors, andof the vital and animal functions; leaving sometimes the common opinions, and delighting in the defence of _Paradoxes_. _E. G. _ That the material substantial Form, is nothing but _mera potentia_, and subsists not by it self: by which means the Author judges, he can freehimself from many great difficulties touching _Generation_ and_Corruption_, which do perplex the other Philosophers. He holds _Epicycles_ to be impossible, and _Excentricks_, not sufficient toexplicate the motion of the Stars; but that all the irregularities of thismotion may be salved by the means of certain _Spiral_ Lines; largelyproving this _Hypothesis_, and particularly explicating the motion of eachPlanet. He denies the middle Region of the Air to be cold; and believes that coldis not necessary to condense the vapours into Water. He admits not that received Axiome, _That the generation of one Body is thecorruption of another_; maintaining that there are _Generations_, to whichno corruption ever preceded; and that it may happen, that one Animalwithout dying may be changed into another Animal. He alledges several reasons to evince, that the Air breathed in, enters notonly into the whole capacity of the Chest, but also into the lower belly. {366} He is of opinion that the Air, which is commonly believed to corrupteasily, is incorruptible; alledging among other reasons, this for one, thatexperience shews, that if a Bottle be exactly stop'd, there is never anymixt Body form'd in it; wherefore, _saith he_, the Air is not corruptedthere. He maintains, that 'tis not the _Magnet_ that draws the Iron, but ratherthe Iron that attracts the _Magnet_. To explain which he affirms, that theLoad-stone spreads abroad out of it self many corpuscles, which thesubstance of the Iron imbibes, and that, as dry things attract those thatare moist, by the same reason Iron drawn the Loadstone. He rejects the _species intentionales_, _Vital_ and _Animal_ Spirits, andholds many other uncommon opinions, touching _Light_, the _Iris_, the _Fluxand Reflux of the Sea_, &c. III. _GUSTUS ORGANUM per _Laurentium Bellini_ novissimè deprehensum. _ The Author proposing to himself to discover both the principal _Organ_ ofthe _Taste_, and the nature of its _object_, begins with the latter, andexamins first, what is _Taste?_ He judges that it is caused by nothing butSalts, which being variously figured, affects the tongue variously:alledging this for his chief reason, that the Salt which is extracted by_Chymists_ out of any mixt body whatever it be, carries away with it allits taste, and that the rest remains tasteless. He adds that the Teeth ingrinding the Food, serve much to extract this Salt: And he notes by the by, that the Teeth are so necessary for preparing the aliment, that certainAnimals which seem to have none, have them in their stomach; and thatnature has put at the entry of the palat of those that are altogetherdestitute of them, certain moveable inequalities, which are to them insteadof Teeth. But then _secondly_, concerning the _Organ_ of Taste, he esteems, that 'tisneither the Flesh, nor the Tongue, nor the Membrans, nor the Nerves foundthere, nor the Glanduls, called _Amygdalinæ_; but those _little eminences_that are found upon the tongue of all Animals. To obtain which, heobserves, 1. That from the middle of the Tongue to the root, as also towards the tip, there are found innumerable _little Risings_ {367} called _Papillares_; butthat from the tip of the Tongue unto the string there is observed none atall. 2. He hath experimented, that if you put _Sal Armoniack_ upon the places ofthe Tongue, where those _Eminencies_ are not, you shall find no Taste; butthat you will find it presently assoon as you put any such Salt, where theyare to be met with. Ergo, _saith he_, those _Eminencies_ are the principalOrgan of Taste. 3. He assures, that with a _Microscope_, may be seen in those _Risings_many little holes, at the bottom whereof there are small nerves, terminating there: But _he directs_, to observe this in live and healthy, not in dead or sick Animals. Having laid down these Observations, he concludes, that the manner, afterwhich Taste is perform'd, is this, That the particles of Salt passingthrough those pores, which pierce the _Papillary Eminences_, andpenetrating as far as to the nerves, that meet them there, do by the meansof their small points prick them; which pricking is called the _Taste_. In the mean time he acknowledges, that before him Signior _Malphigi_, Professor at _Messina_, had made some of these discoveries. The notice of these two last Books we owe to the _French Journal_. * * * * * _Correct in Number. _ 19. Page, 342. Line, 33. Read _mixt Ores_, in stead of, _mixt with Ores_. * * * * * _London_, Printed for _John Martin_, Printer to the _Royal Society_, andare to be sold at the _Bell_ a little without _Temple-Bar_. {369} * * * * * _Numb. _ 21. PHILOSOPHICAL_TRANSACTIONS. _ * * * * * _Munday_, _January_ 21. 1666. * * * * * The Contents. _An Account, formerly promised, of Monsieur _Hevelius's_ Calculation of the late _Solar Eclipse's_ Quantity, Duration, &c. The Figure of the Star in the Constellation of _Cygnus_, together with the New Star in it, discovered some years ago, and very lately seen again by the same Mr. _Hevelius_. An Extract of a Letter, written by Mr. _Auzout_, concerning a way of his, for taking the _Diameters_ of the Planets, and for knowing the _Parallax_ of the _Moon_: Giving also a Reason, why in the _Solar Eclipse_ above-mentioned, the _Diameter_ of the _Moon_ did increase about the end. A Relation of the loss of the Way to prepare the _Bononian Stone_ for shining. A Description of a _Swedish Stone_, affording _Sulphur, Vitriol, Allum_, and _Minium_. A Relation of the Raining of Ashes. An Extract of a Letter from _Rome_, rectifying the Relation of _Salamanders_ living in Fire. An Account of several Engagements for _Observing of Tydes_. Some Suggestions for Remedies against Cold. A Relation of an uncommon accident in two Aged Persons. An Account of Two Books, _I. ISMAELIS BULLIALDI ad Astronomos Monita duo: Primum, de Stella Nova, in _Collo Ceti_ ante aliquot annos visa. Alterum, de Nebulosa Stella in _Andromedæ_ Cinguli parte _Borea_, ante biennium iterum ortâ. II. ENTRETIENS sur les vies & sur les Ouvrages des plus excellens Peintres, antients & modernes, par M. FELIBIEN_. _ * * * * * _Monsieur _Hevelius_'s Calculation of the late _Solar Eclipse's_ Quantity, Duration, &c. _ This _Calculus_ was not long since communicated by Monsieur _Hevelius_ in aLetter to the _Publisher_, as follows, {370} _Eclipsis Solaris. _ _Observata An. 1666. D. 2. Julii, St. N. Mane, à Johanne Hevelio. _ ----+-----------------+-----------+----------+--------+--------+---- Ordo| |Temp æstin | |Altitude| | Pha-|Quantitas |sec. Horol |Temp. Sec. | [Sun] |Tempus | sium|Phasium |ambulat. |Sciother. | |correct. |Anim. ----+-----------------+-----------+----------+--------+--------+---- | |H. ' " |H. ' " | °. ' |H. ' " | | |5. 51. 11 |5. 51. 0 |17. 45 |5. 53. 12 | 1. | |5. 57. 5 |5. 57. 0 |18. 37 |5. 59. 28 | | |6. 0. 0 |6. 0. 0 |18. 55 |6. 1. 28 | ----+-----------------+-----------+----------+--------+--------+---- |Initium |6. 55. 30 | | |6. 57. 30 | 2. 1 |0-3/8 dig. |6. 57. 30 | | |5. 59. 30 | 2 |0-3/4 |7. 0. 23 |7. 0. 0 | |7. 2. 23 | 3 |1-1/8 |7. 2. 30 |7. 2. 0 | |7. 4. 30 | ----+-----------------+-----------+----------+--------+--------+---- 4 |1-1/2 dig. |7. 4. 50 |7. 5 ferè. | |7. 6. 50 | 5 |1-3/8 ferè. |7. 10. 57 |7. 10 | |7. 12. 57 | 6 |3-3/8 |7. 14. 59 |7. 15 | |7. 16. 59 | 7 |3-3/4 |7. 17. 50 |7. 18 ferè. | |7. 19. 50 | ----+-----------------+-----------+----------+--------+--------+---- 8 |4-3/8 dig. |7. 21. 35 |7. 21 | |7. 23. 35 | 9 |4-2/3 |7. 23. 43 |7. 23 ferè. | |7. 25. 43 | 10 |5-1/4 |7. 27. 53 |7. 28 | |7. 29. 53 | 3. 11 |6 |7. 31. 50 |7. 32 | |7. 33. 50 | ----+-----------------+-----------+----------+--------+--------+---- 12 |6-3/4 |7. 36. 55 |7. 37 | |7. 38. 55 | 13 |6-7/8 paul. Plus. |7. 38. 5 |7. 38 | |7. 40. 0 | 14 |7-1/8 |7. 39. 45 |7. 39 | |7. 41. 45 | 15 |7-1/4 paul. Plus. |7. 42. 30 |7. 42 | |7. 44. 30 | ----+-----------------+-----------+----------+--------+--------+---- 16 |7-1/2 |7. 44. 6 |7. 44 | |7. 46. 6 | 17 |7-2/3 |7. 46. 0 |7. 46 | |7. 48. 0 | 18 |8 ferè |7. 48. 25 |7. 48 ferè | |7. 50. 25 | 19 |8-1/5 |7. 51. 15 |7. 51 | |7. 53. 15 | ----+-----------------+-----------+----------+--------+--------+---- 20 |8-1/4 paul. Plus. |7. 53. 37 |7. 52 | |7. 55. 37 | 21 |8-3/4 |7. 55. 45 |7. 56 ferè | |7. 57. 45 | 22 |8-3/4 paul. Min. |7. 59. 5 |7. 59 | |8. 1. 5 | 4. 23 |8-1/5 |8. 6. 30 |8. 6 | |8. 8. 30 | {371} ----+-----------------+-----------+----------+--------+--------+---- 24 |7-3/4 |8. 11. 25 |8. 12 | |8. 13. 25 | 5. 25 |7-1/4 ferè. |8. 17. 30 |8. 18 | |8. 19. 30 | 26 |7 ferè. |8. 19. 41 |8. 19 | |8. 21. 41 | 27 |5-7/8 |8. 28. 8 |8. 28 | |8. 30. 8 | ----+-----------------+-----------+----------+--------+--------+---- 28 |5-1/2 ferè. |8. 30. 14 |8. 30 | |8. 32. 14 | 29 |4-3/4 |8. 36. 25 |8. 36 | |8. 38. 25 | 30 |3-5/8 |8. 43. 19 |8. 43 | |8. 45. 19 | 31 |3-1/4 |8. 46. 12 |8. 46 ferè. | |8. 48. 12 | ----+-----------------+-----------+----------+--------+--------+---- 32 |3 |8. 47. 32 |8. 47 | |8. 29. 32 | 33 |2-3/4 |8. 50. 57 |8. 50 | |8. 52. 57 | 34 |2-1/2 ferè |8. 54. 15 |8. 54 | |8. 56. 15 | 35 |1-3/4 |8. 58. 24 |8. 58 | |9. 0. 24 | ----+-----------------+-----------+----------+--------+--------+---- 36 |1-1/8 |8. 59. 35 |8. 59 | |9. 1. 35 | 37 |0-5/6 |9. 1. 38 |9. 1 | |9. 3. 38 | 38 |0-1/2 |9. 3. 20 |9. 3 |Altit. |9. 5. 20 | 39 |Finis. |9. 6. 53 |9. 6 |[Sun] |9. 8. 53 | 6. ----+-----------------+-----------+----------+--------+--------+---- | |9. 23. 6 | |47. 33 |9. 25 28 | | |9. 24. 16 | |47. 42 |9. 26. 45 | | |9. 28. 29 | |48. 10 |9. 30. 42 | | |9. 30. 36 | |48. 28 |9. 33. 12 | _Animadvertenda. _ 1. Quòd Sciatericum cum correcto tempore non omnino convenit, non-nisiLineæ Meridianæ imputandum. 2. Initium circa 79 gr. à puncto _Zenith_ occasum versùs contigit. 3. Hujusque Semidiameter Lunæ æqualis extitit Solari. 4. Maxima obscuratio extitit digit. 8. 25' hora 8. 2'. 5. Hic Semidiameter _Lunæ/_ ad 8" vel 9" major apparuit. * * _See Numb. 19 of the Philosophical Transactions, p. 347. _ 6. Punctum finis distitit à verticali ad Ortum 143 gr. This Observation is by the same _Astronomer_, represented also by the_Figures AAAAAA_; as that of the _Horizontal Eclipse_ of the _Moon_, is, bythe _Figures BB_. [Illustration] [Illustration] [Illustration] [Illustration] {372} * * * * * _The Figure of the Stars in the Constellation of _Cygnus_; together withthe _New Star_ in it, discover'd some years since, and very lately seen byM. _Hevelius_ again. _ The Relation concerning this _New Star_ in the _Brest of Cygnus_, verylately discover'd again at _Dantzick_, by M. _Hevelius_, was publish't_Numb_. 19. _p_. 349. The _Figure_ of that _Constellation_, with the _NewStar_ in it, was thus, hastily drawn, sent over by that Observer. [Illustration] {373} * * * * * _An Extract of a Letter written _Decemb. 28. 1666_. By M. _Auzout_ to thePublisher, concerning a way of his, for taking the _Diameters_ of the_Planets_, and for knowing the _Parallax_ of the _Moon_; as also theReason, why in the _Solar Eclipse_ above calculated, the _Diameter_ of the_Moon_ did increase about the end. _ I did apply my self the last Summer to the taking of the _Diameters_ of theSun, Moon, and the other Planets, by a Method, which one M. _Picard_ and myself have, esteem'd by Us the best of all those, that have been practis'dhitherto; since we can take the _Diameters_ to _Second Minutes_, being ableto divide one foot into 24000. Or 30000. Parts, scarce failing as much asin one only part, so as we can in a manner be _assur'd_, not to deceive ourselves in 3. Or 4. _seconds_. I shall not now tell you my Observations, butI may very well assure you, that the _Diameter_ of the _Sun_ has not beenmuch less in his _Apogee_, than 31. M. 37. Or 40. Sec. And certainly notlesse than 31. M. 35. Sec. And that at present in his _Perigee_ it passesnot 32. M. 45. Sec. And may be lesse by a second or two. That, which is atthe present troublesome, is, that the _Vertical_ Diameter, which is themost easie to take, is diminisht, even at _Noon_, by 8. Or 9. Sec. , becauseof the _Refractions_, which are much greater in Winter than Summer at thesame height; and that the _Horizontal_ Diameter is difficult, because ofthe swift motion of the Heavens. As for the _Moon_, I never yet found her Diameter less than 29. M. 44. Or45. Sec. And I have not seen it pass 33. M. Or if it hath, it was only by afew _seconds_. But I have not yet taken her in all the kinds of situationsof the _Apogees_ and _Perigees_ which happen, with the _Conjunctions_ and_Quadratures_. I do not mention all, what can be deduced from thence, butif you have Persons at _London_, that observe these _Diameters_, we mayentertain our selves more about this Subject, another time. I shall onlytell you, that I have found a Way to know the _Parallax_ of the _Moon_, bythe means of her _Diameter_: _Vid_. If on a day, when she is to be in her_Apogee_ or _Perigee_, and in the most _Boreal_ Signes, you take herDiameter towards the _Horizon_, and then towards the _South_, with her_Altitudes_ {374} above the Horizon. For, if the Observation of theDiameters be exact; as in these Situations the Moon changes notconsiderably her Distance from the Earth in 6. Or 7. Hours, the_Difference_ of the Diameters will shew the Proportion there is of herDistance, with the Semi-diameter of the Earth. I do not enlarge, becausethat as soon as one hath this _Idea_, the rest is easie. The same would yetbe practis'd better in the places, where the Moon passes through the_Zenith_, than here, for the greater the difference is of the Heights, thegreater is that of the Diameters. I do not note (for it easily appears)that, if one were under the same _Meridian_, or the same _Azimuth_ in twovery different places, and took at the same time the Diameter of the Moon, one would do the same thing, though this Method goes not to preciseness. From what has been said, may be collected the reason of the Observation, which M. _Hevelius_ made in the last _Eclipse of the Sun_, touching theincrease of the Moon's Diameter about the end. I am exceeding glad, that aperson, who probably knew not the cause of it, has made the Experiment: butit is strange, that until now no Astronomer has foreseen, that that shouldhappen, nor given any precepts for the Change of the _Moons Diameter_ inthe _Eclipses of the Sun_, according to the places, where they shouldhappen, and according to the Hour and Height, the Moon should have. For, what hapned in that _Eclipse_ of Augmentation, would have faln outcontrarily, if it had been in the Evening; for, the Moon, which in that_Eclipse_, that began in the Morning, was higher about the end than at thebeginning, was nearer us, and consequently was to appear bigger: But if the_Eclipse_ should happen in the Evening, she would be lower at the end, andtherefore more distant from us, and consequently appear lesser. So also intwo different places, whereof one should have the Eclipse in the Morning, and the other at Noon, the Moon should appear bigger to him that hath it atNoon: And she must likewise appear bigger to those, who shall have a leser_Elevation_ of the _Pole_ under the same _Meridian_, because the Moon willbe nearer them. I wish, I could satisfie you about the _Optick Glasses_ of Signior_Burattini_ in _Poland_, which he hath sent hither; but I have not yet seentheir performances my self. I only saw once the Glasses, {375} which areperfectly well wrought and well polisht. Those, that have tried them, findthem very good; but they are only, the one of 10, the other of 8. Foot. Agood Astronomer told me, that they would bear a great _Aperture_ in respectof their length. I do not well know, what to say to yours concerning M. _Hevelius_. Meanwhile, the interest of truth, and the obliging manner, he has treated mewith, engage me to answer him, in the matter of the _Comets_: I amperswaded, I shall convince him; but since he hath taken the _IllustriousRoyal Society_ for Judge, I accept that with all my heart. * * * * * _A Relation of the loss of the Way to prepare the _Bononian Stone_ forshining. _ [Sidenote: * It is hoped notwithstanding (which also a late Letter fromabroad does hint) that some or other of the _Italian_ Vertuosi at_Florence_ have secured this Secret. ] Though several Persons have pretended to know the Art of preparing andcalcining the _Bononian_ Stone, for keeping a while the Light once imbibed;yet there hath been indeed but one, who had the true secret of performingit. This was an _Ecclesiastick_, who is now dead, without having left thatskill of his to any one, as Letters from _Italy_ and _France_, some whilesince, did inform. There is no substance, in Nature, known to us, that haththe effect of this Stone; so that (to the shame of the present Age) this_Phænomenon_ is not like to be found any where, but in Books, except somehappy _Genius_ light upon same or the like skill. * * * * * * _A Description of a _Swedish_ Stone, which affords _Sulphur_, _Vitriol_, _Allum_ and _Minium_. _ This was communicated to the _R. Society_ by Sir _Gilbert Talbot_ Knight, aWorthy Member of that Body, as he had received it in _Denmark_, being hisMajesties Extraordinary Envoy there; as follows, [Illustration] There is a Stone in _Sweden_ of a Yellow Colour, intermixed with streaks ofwhite (as if composed of Gold and Silver) and heavy withal. It is found infirm Rocks, and runs in Veins, {376} upon which they lay Wood, and set iton fire. When the Stone is thus heated, they cast Water upon it, to make itrend, and then dig it up with Mattocks. This done, they break it intosmaller pieces; and put it into Iron-pots, of the shape represented by_Figure_ C; the mouth of the one going into the other. These they place, the _one_ in the Oven upon an Iron fork sloping, so that, the Stone beingmelted, it may run into the _other_, which stands at the mouth of the Oven, supported upon an Iron. The first running of the Stone is _Sulphur_. The remainder of the burned Stone is carry'd out, and laid upon a highHill, where it lies exposed to the Sun and Air for the space of two years, and then taketh fire of it self, casting forth a thin blew flame, scarcediscernable in the day time. This being consumed, leaveth a blew dustbehind it; which the Workmen observe, and mark with woodden pins. This theydig up, and carry into the Work-house, and put it into great Tubs of Water, where it infuseth 24. Hours or more. The Water they afterward boyl inKettles, as we do Saltpeter, and put it into cooling Tubs, wherein theyplace crosse Sticks, and on them the _Vitriol_ fastens, as Sugar-candydoth. The Water, that remains after the extraction of the _Vitriol_, they mixwith an eight part of Urin and the Lees of Wood-ashes, which is againboyled very strong, and being set to cool in Tubbs, crosse Sticks arelikewise placed, and thereon the _Allum_ fastens. In the Water, which remains after the _Allum_, is found a Sediment, whichbeing separated from the Water, is put into an Oven, and Wood laid upon itand fired, till it become red, which makes the _Minium_, wherewith theypaint their Houses, and make plaister. _So far this Description_; Which gave occasion to a curious person to callto mind, That there was a kind of Stone in the _North_ of _England_, yielding the same substances, except _Minium_. {377} * * * * * _A Relation of the Raining of _Ashes_, in the _Archipelago_, upon theEruption of Mount _Vesuvius_, some years ago. _ This came but lately to hand from that knowing person, Mr. _HenryRobinson_, and was thought fit to be now inserted here, that it might notbe lost, though it hath hapned above 30 years ago. It was contained in aLetter, (subscribed by Capt. _Will. Badily_) in these words: [Sidenote: * Some of these Ashes were produced by Mr. _John Evelyn_, beforethe _Royal Society_. ] The 6^{th. } of _December_ 1631, being in the Gulf of _Volo_, riding atAnchor, about ten of the Clock that Night, it began to rain Sand or Ashes, and continued till two of the Clock the next Morning. It was about twoinches thick on the Deck, so that we cast it over board with Shovels, as wedid Snow the day before: The quantity of a Bushel we brought home, andpresented to several Friends *, especially to the Masters of _TrinityHouse_. There was in our Company, Capt. _John Wilds_ Commander of the_Dragon_, and Capt. _Anthony Watts_, Commander of the _Elisabeth_ and_Dorcas_. There was no Wind stirring, when these Ashes fell, it did notfall onely in the places, where we were, but likewise in other parts, asShips were coming from St. _John D'Acre_ to our Port; they being at thattime a hundred Leagues from us. We compared the Ashes together, and foundthem both one. If you desire to see the Ashes, let me know. * * * * * _An Extract Of A Letter not long since written from _Rome_, rectifying theRelation of _Salamanders_ living in Fire. _ This came from that Expert Anatomist M. _Steno_, to Dr. _Croone Videl_. That a Knight called _Corvini_, had assured him, that, having cast a_Salamander_, brought him out of the _Indies_, into the Fire, the Animalthereupon swell'd presently, and then vomited store of thick slimy matter, which did put out the neighbouring Coals, to which the _Salamander_ retiredimmediately, putting them out again in the same manner, as soon as they{378} rekindled, and by this means saving himself from the force of theFire, for the space of two hours, the Gentleman above-mentioned being thenunwilling to hazard the Creature any further: That afterwards it lived nineMonths: That he had kept it eleven Months without any other food, but whatit took by licking the Earth, on which it moved, and on which it had beenbrought out of the _Indies_; which at first was covered with a thickmoisture, but being dried afterwards, the Urin of the Animal served tomoisten the same. After the eleven Months, the Owner having a mind to try, how the Animal would do upon _Italian_ Earth, it died three dayes after ithad changed the Earth. * * * * * _An Account of several Engagements for Observing of Tydes. _ Since nothing is more important for discovering the Cause of that Grand_Phænomenon_ of Nature, the _Flux_ and _Reflux of the Sea_, than a true andfull _History of the Tydes_; the _Virtuosi_ of _England_ have of late(especially since the Publication of Dr. _Wallis_ his _Theory_ touchingthat _Apparence_) taken care, to direct and recommend in several parts ofthe World, and particularly in the most proper places of these _Ilands_, such Observations, as may contribute to the elucidating of that Subject. And as formerly they have sent their _Inquiries_ of this Nature to the Isleof St. _Helena_, situated in the open Ocean beyond the _Æquinoctial_, andalready received some account thereupon; so they have since dispatcht thelike for the _Bermudas_, an _Isle_ that hath no less conveniency ofsituation for that purpose. And they intend (as will more amply appear, Godpermitting, in a short time) to lodge with such Masters of Ships andPilots, as shall sayl into remote parts, very particular directions of thatkind, to be printed at the _Royal Societies_ charges, and to be committedto the care of the Masters of _Trinity House_ for disposing of them to thatend. And, as for the Observations, to be made in these Kingdoms; 'tis hoped, that the Masters in the Art of Navigation at _Bristol_ (Mr. _Standridge_and Mr. _Iff_) will undertake that business with affection and care: theformer of these two having already (as we are informed from a good hand)made a Collection of the Tydes; {379} for some years past, and found themdiffering from former Observations and Tables; the other promising futurediligence in this matter; noting in the mean time, that some Tydes of lastAutumn were so far differing from former Observations, that neither he, norany others there, could make any thing of it. We must not omit here to mention the readiness, expressed by these worthyGentlemen, Mr. _Rob. Boyle_, Sir _Rob. Moray_, and Mr. _Henry Powle_, forconcurring in this Work; the first, having undertaken to recommendObservations of this nature, to be made, upon the _Western_ Coast of_Ireland_ *; the second, upon the West of _Scotland_; and the third, in theIsle of _Lundy_; to whom we must adde the inquisitive Mr. _Sam. Colepresse_, for _Plymouth_, and the _Lands-end_. Besides, we hope toengage the curious of _France_ in the same undertaking, especially forprocuring, besides what is known already concerning that place, a veryparticular and exact account of the Tydes upon the Coast of _Britany_, where (especially about St. _Malo_) they are found to rise to admiration, even to 60, 70, and sometime 80, feet, at the New and Full Moon. * The Observations particularly recommended for that Coast, are these; 1. At what hour it is High-water on the day of the New and Full Moon, upon every Cape and Bay of the Western Coast of _Ireland_. 2. How long after the New and Full Moon the highest Spring-tides fall out. 3. What are the perpendicular heights of the Flood, both at the ordinary, and the Spring-tydes. * * * * * _Some Suggestions for Remedies against _Cold_. _ As there have been Remedies found out against excessive _Heat_, and Meansof cooling Meat and Drink; so it was lately, on the occasion of the sharpSeason, suggested, That Remedies might be thought on against _Cold_; andthat particularly it might be inquired into, 1. What things in Nature, or by Art, or Mechanical contrivance will retaina warming Heat longest, or a melting or scorching Heat? 2. What will continue or maintain Fire longest? Some that observe common practises and vulgar Trades, take notice, That_Joyners_ use _Leaden-Pots_ for their Glue, alledging for a Reason, ThatLead, being a close Mettal, retains the heat {380} longer than otherMettals. _Cary_'s Warming-stone promised a warmth for six or eight hours;if it performed but for two or three hours, it would be of great use. 'Tisfound by sad experience, how hurtful Bright Fires, and especially ofStone-coal are to the Eyes. To retain Fire long, certain _Black_ Earths are useful, as we were newlyinformed by the Inquisitive Dr. _B. _ That a Gentleman in _Sommertsetshire_, called Mr. _Speke_, had bountifully obliged _Ilminster_, and hisNeighborhood, by a Black Fat-Earth lately found in his Park. But the sameCorrespondent adds, That he never saw any parallel to a _Sea-weed_, whichhe and some of his Fellow-Students had in _Cambridge_ in the mouth of aBarrel of good Oysters. It was smaller than Pease-halm, yet cut, it lastedtwo very great Fires of Sea-coal, burning bright in the midst of the Fire;and by a stroak of the Tongues, it fell into the Hearth, jingling likeMettal. * * * * * _A Relation of an uncommon Accident in two Aged Persons. _ This was imparted by the above-mentioned Mr. _Colepresse_, who assures inhis Letter, containing this Account, That the matter of fact was thorowlyexamined by himself, and that he was fully, and in all respects, satisfiedof the truth thereof. _The Relation of the one, is in these words. _ _Joseh Shute_ Clerk, Parson of _Mary_ (nigh _Plymouth_) in the County of_Devon_, aged 81 years, being a temperate man, and of an healthyconstitution, having the in-most Grinder loose, and so remaining, perceived, that his mouth, about three Moneths since, was somewhatstreightned; and upon inquiry into the cause of it, found, That he had anew Tooth (the third Grinder) being the innermost of the upper Jaw in theRight Cheek, which still remains firm. _The Account of the other follows thus. _ _Maria Stert_ of _Benecliffe_, in _Plympton St. Mary_ (near _Plymouth_) in_Devon_, aged about 75 years, an healthy person, having had nine children, about the fortieth year of her age lost three of her {381} upper_Incisores_ or _Cutters_, the other drawn out, and so remained Toothless, as to them, for about 25 years, when she perceived, that a new Tooth cameforth (without any pain) next the _Canini_ of the left Cheek: And about twoyears after, another Tooth grew out likewise without pain, close by theformer. The first whereof, never came to above half the length of herformer _Cutters_, the latter scarce breaking the skin: Both which yetproved serviceable, till about six weeks since, when she eating (no hard, crusty, or solid) Meat, that Tooth which came out first, fell down into herMouth, without any loosness before hand perceived, or any pain; which hadnot a phang like other _Cutters_, but much less, and shorter. The otherabides firm, and serviceable. To the truth of these Relations, not onely the said _Joseph Shute_ and_Maria Stert_, have put the one his name, the other her Mark, the third andseventh of _January_, 1666. But also Sir _William Strode_, and Mr. _Colepresse_ have subscribed the same, as believing the Relation to betrue. * * * * * _An Account of two Books. _ __I. ISMAELIS BULLIALDI_ ad Astronomos Monita duo: Primum, De Stella Nova, quæ in Collo Ceti ante annos aliquot visa est. Alterum, De Nebulosa inAndromeda Cinguli parte Borea, ante biennium iterum orta. _ The chief end of the _Author_ in publishing this Tract, seems to be, Toexcite Astronomers to a diligent observation, both of that _New Star_ inthe _Neck_ of the _Whale_, to be seen in _February_ and _March_ next; andof that other, in the Northern part of _Andromeda's Girdle_, to be seen atthis very present. As to the _former_ of these Stars, _he affirms_, that, as it hath appearedfor many years in the said place, so it will in the beginning of _March_next appear equal to the Stars of the _third Magnitude_, or perhaps bigger;and that about the end of the same Month, if the Crepuscle do not hinder, the greatest _Phasis_ of it will appear, if so be, that it keep the sameAnalogy of Motions and Periods, which it observed from _An. _ 1638. To _An. _1664. Where he takes notice of the Causes, why its two greatest Appearancescould not be seen, _An. _ 1664, 1665, 1666; and how he {382} comes to know, that in the beginning of _March_ next, It will equal, or even exceed theStars of the _Third Magnitude_; noting, that from the Observations hithertomade of this Star, it is manifest, that the _greatest Phases_ thereof doevery year anticipate by 32. Or 33. Dayes; forasmuch as _An. _ 1660. Its_greatest Appearance_ was about the end of _October_ and the beginning of_November_; _An. _ 1661. About the end of _September_, or the beginning of_October_; _An. _ 1662. About the end of _August_, &c. So that this year itmust be in _March_, if the former Analogy do hold. He collects also from the Observations, That one _Period_ from the_greatest Phasis_ to the next, consists of about 333. Dayes: but that theinterval of the time betwixt the times of its beginning to appear equal tothe Stars of the _Sixt Magnitude_, and of its ending to do so, consists ofabout 120. Dayes: And that its _greatest Appearance_ lasts about 15. Dayes:All which yet he would have understood with some latitude. This done, he proceeds to the investigation of the Causes of theVicissitudes in the Emersion and Dis-appearance of this Star, and havingdiscoursed, That the apparent Increase and Decrement of every Lucid Bodyproceeds _either_ from its changed distance from the Eye of the Observer;_or_ from its various site and position in respect of him, whereby theangle of Vision is changed; or from the increase or diminution of the bulkof the lucid body it self: and having also demonstrated it impossible, thatthis Star should move in a _Circle_, or in an _Ellipsis_; and proved itimprobable that it should move in a _Strait Line_, he concludes, that therecan be no other genuin, or at least, no other more probable cause of itsEmersion and Occultation, than this, That the bigger part of that roundBody is obscure and inconspicuous to us, and its lesser part lucid, thewhole Body turning about its own Center, and one Axe; whereby for onedeterminate space of time it exhibits its lucid part to the Earth, foranother, subducts it: it not being likely, that fires should be kindled inthe Body of that Star, and that the matter thereof should at certain timestake fire and shine, at other times be extinguisht upon the consumption ofthat matter. _So far of that Star. _ As to the other in the _Girdle_ of _Andromeda_, seenabout the beginning of _An. _ 1665; he relates, that, when in the end of1664. The World beheld the then appearing _Comet_, {383} Astronomersobserved also this new _Phænomenon_, which was called by them _Nebulosa inCingulo Andromedæ_. Concerning which, he notes, that the same had beenalready seen many years before by _Simon Narius_, vid. _An. _ 1612. Whenwith a _Telescope_ he search'd for the _Satellits_ of _Jupiter_, andobserved their motions; alledging for proof hereof, the said _Authors_ ownwords, out of his own Book, _De Mundo Joviali_, publisht _An. _ 1614. Andfarther shews, that it hath formerly appear'd (about 150. Years ago) andbeen taken notice off by an expert, though Anonymous, Astronomer; whosewords he cites out of a _Manuscript_, brought out of _Holland_ by theExcellent _Jacobus Augustus Thuanus_, returning from his Embassy to_Paris_; wherein also was marked the _Figure_ of that _Phænomenon_;represented in print by our Author: who from all this collects, that, whereas this Star hath been seen formerly, and that 150. Years since, butyet neither observed by _Hipparchus_, nor any other of the Antients, thatwe can find; nor also in the former Age by _Tycho Brahe_, nor in our Age, by _Bayerus_; and appear'd also in the Month of _November_ last (wherein hewrote this _Tract_) much lessened and obscure, after it had, two years ago, shone very bright; that therefore it must needs appear and dis-appear byturns, like those in the _Necks_ of the _Whale_ and _Swan_. __II. _ ENTRIENS sur les Vies et sur les Ouvrages_ Des plus excellensPeintres, Anciens et Modernes, par Monsieur_ FELIBIEN. _ This Author, having first discoursed of that Royal Pallace the _Louvre_, and the Designs of finishing it; passes on to the Art of _Picturing_, andtreats of the three principal things, wherein a good Master of the Art mustexcel, _vid. _ the Composition, Designing, and Laying on of Colours, whichdone, he ravels into the Origine, and deduces the Progress of Painting, andrelates what is most remarkable in the Lives of the Antient Painters: Andamong many particulars, he observes in the Life of _Andreas de Sarte_, howdifficult it is, to judge well of a Picture; relating, that a Duke of_Mantua_, having obtained of _Clement_ VII. A Pourtrait of _Leo_ X. Whichhad been done by _Raphael Urbin_, and was at _Florence_, those of that Townbeing unwilling to lose so excellent a {384} piece, caused a Copy thereofto be made by the said _Andreas de Sarte_, which they sent instead of theOriginal. This _Copy_ was so perfect, that _Julio Romano_, who had beenbred and taught by _Raphael_, and was one of the best Painters of _Italy_, took it for an _Original_; and would never have been undeceived, if one_Vasari_ had not assured him, that it was but a Copy, which himself hadseen made, and had not shew'd him certain marks, that were there put todiscriminate it from the Original. In the _Second_ Part, the Author has set down all that is requisite tojudge and discourse well of Painting. But, to add Examples to Precepts, hediscourses of the _Modern_ Painters, and making a Description of their bestWorks, he takes occasion to observe, what is there found most excellent, and to shew, how they have put in practice the Rules of Art. He treats alsoof the declining of Painting, and affirms, that nothing considerable hathbeen done in it from the time of _Constantine_, till _An. _ 1240. When one, _Cimabue_, began to raise this Art again. After this, he give a List of thePainters, that since have been famous for their Works, preferring beforeall others, _Raphael Urbin_. The last of all is the above-mention'd _Andrède Sartes_, who died, _An. _ 1530. And whom the liberality of _Francis_ I. Had drawn into _France_. * * * * * The Printing of these Tracts is now return'd to the first Printer thereof, as being somewhat re-setled after the late sad Fire of _London_. _FINIS. _ * * * * * In the _SAVOY_, Printed by _T. N. _ for _John Martyn_, Printer to the _RoyalSociety_, and are to be sold at his Shop a little without Temple-Bar, 1667. {385} * * * * * _Numb. _ 22. PHILOSOPHICAL_TRANSACTIONS. _ * * * * * _Monday_, _February_ 11. 1666. * * * * * The Contents. _Trials proposed to be made for the Improvement of the Experiment of _Transfusing Blood out of one live Animal into another_. A Method for _Observing the Eclipses of the Moon_, free from the Common Inconveniences. An Account of some Celestial Observations lately made at _Madrid_. Extract of a Letter, lately written to the Publisher, containing some observations about _Insects_ and their Inoxiousness, &c. An Account of some Books, _vid. _ _I. TOME TROISIEME DES LETTRES DE M. DESCARTES. II. ASTRONOMIA REFORMATA P. RICCIOLI. III. ANATOME MEDULLÆ SPINALIS ET NERVORUM_, inde provenientium, _GERARDI BLASII_, M. D. An Advertisement about the re-printing of M. _Evelyns_ Sylva and Pomona. A _Table_ of the _Transactions_, printed these two years. _ * * * * * _Tryals proposed by Mr. _Boyle_ to Dr. _Lower_, to be made by him, for theImprovement of Tranfusing blood out of one live Animal into another;promised _Numb. 20. P. 357_. _ The following _Queries_ and _Tryals_ were written long since, and readabout a Moneth ago in the _R Society_, and do now come forth against theAuthors intention, at the earnest desire of some Learned Persons, andparticualrly of the worthy _Doctor_, to whom they were addressed; whothinks, they may excite and assist others in a matter, which, to be wellprosecuted, will require many hands. At the reading of them, the _Author_declared, that of divers of them he thought he could fore-see the Events, but {386} yet judged it fit, not to omit them, because the Importance ofthe _Theories_, they may give light to, may make the Tryals recompence thepains, whether the success favour the _Affirmative_ or the _Negative_ ofthe Question, by enabling us to determine the one or the other upon surergrounds, than we could otherwise do. And this Advertisement he desires maybe applied to those other Papers of his, that consist of _Quæries_ orproposed _Tryals_. _The _Quæries_ themselves follow. _ 1. Whether by this way of Transfusing Blood; the disposition of IndividualAnimals of the same kind, may not be much altered? (As whether a _fierce_Dog, by being often quite new stocked with the blood of a _cowardly_ Dog, may not become more tame; _& vice versa, &c_?) 2. Whether immediately upon the unbinding of a Dog, replenisht withadventitious blood, he will know and fawn upon his Master; and do the likecustomary things as before? And whether he will do such things better orworse at some time after the Operation? 3. Whether those Dogs, that have _Peculiarities_, will have them eitherabolisht, or at least much impaired by transfusion of blood? (As whetherthe blood of a _Mastiff_, being frequently transfused into a _Blood-hound_, or a _Spaniel_, will not prejudice them in point of scent?) 4. Whether acquired Habits will be destroy'd or impair'd by thisExperiment? (As whether a Dog, taught to fetch and carry, or to dive afterDucks, or to sett, will after frequent and full recruits of the blood ofDogs unfit for those Exercises, be as good at them, as before?) 5. Whether any considerable change is to be observ'd in the Pulse, Urin, and other Excrements of the _Recipient_ Animal, by this Operation, or thequantity of his insensible Transpiration? 6. Whether the _Emittent_ Dog, being full fed at such a distance of timebefore the Operation, that the mass of blood may be suppos'd to abound with_Chyle_, the _Recipient_ Dog, being before hungry, will lose his appetite, more than if the _Emittent_ Dogs blood had not been so chylous? And howlong, upon a {387} Vein opened of a Dog, the admitted blood will be foundto retain _Chyle_? 7. Whether a Dog may be kept alive without eating by the frequent Injectionof the Chyle of another, taken freshly from the Receptacle, into the Veinsof the _Recipient_ Dog? 8. Whether a Dog, that is _sick_ of some disease chiefly imputable to themass of blood, may be cured by exchanging it for that of a _sound_ Dog? Andwhether a _sound_ Dog may receive such diseases from the blood of a _sick_one, as are not otherwise of an infectious nature? 9. What will be the Operation of frequently stocking (which is feasibleenough) an _old_ and feeble Dog with the blood of _young_ ones, as toliveliness, dulness, drowsiness, squeamishness, &c. , _et vice versa_? 10. Whether a _small_ young Dog, by being often fresh stockt with the bloodof a young Dog of a _larger_ kind, will grow bigger, than the ordinary sizeof his own kind? 11. Whether any Medicated Liquors may be injected together with the bloodinto the _Recipient_ Dog? And in case they may, whether there will be anyconsiderable difference found between the separations made on thisoccasion, and those, which would be made, in case such Medicated Liquorshad been injected with some other Vehicle, or alone, or taken in at themouth? 12. Whether a Purging Medicine, being given to the _Emittent_ Dog a whilebefore the Operation, the _Recipient_ Dog will be thereby purged, and how?(which Experiment may be hugely varied. ) 13. Whether the Operation may be successfully practis'd, in case theinjected blood be that of an Animal of another _Species_, as of a _Calf_into a _Dog_, &c. And of a _Cold_ Animal, as of a _Fish_, or _Frog_, or_Tortoise_, into the Vessels of a _Hot_ Animal, and _vice versa_? 14. Whether the _Colour_ of the Hair or Feathers of the _Recipient_ Animal, by the frequent repeating of this Operation, will be changed into that ofthe _Emittent_? 15. Whether by frequently transfusing into the same Dog, the blood of someAnimal of another _Species_, something further, and more tending to somedegrees of a change of _Species_, may {388} be effected, at least inAnimals near of Kin; (As Spaniels and Setting Dogs, Irish Grey-hounds andordinary Grey-hounds, &c?) 16. Whether the Transfusion may be practic'd upon pregnant Bitches, atleast at certain times of their gravidation? And what effect it will haveupon the Whelps? _There_ were some other _Quæries_ proposed by the same _Author_; as, theweighing of the _Emittent_ Animal before the Operation, that (making anabatement for the Effluviums, and for the Excrements, if it voids any) itmay appear, how much blood it really loses. To which were annext diversothers not so fit to be perused but by _Physitians_, and therefore hereomitted. * * * * * _A Method for Observing the _Eclipses of the Moon_, free from the CommonInconveniencies, as it was left by the Learned Mr. _Rook_, late_Gresham_-Professor of Geometry. _ Eclipses of the Moon are observed for two principal ends; One_Astronomical_, that by comparing Observations with Calculations, the_Theory_ of the _Moons Motion_ may be perfected, and the _Tables_ thereofreformed: the other, _Geographical_, that by comparing among themselves theObservations of the same _Ecliptick Phases_, made in _divers_ places, the_Difference_ of _Meridians_ or _Longitudes_ of those places may bediscerned. The Knowledge of the Eclipse's Quantity and Duration, the Shadows, Curvity, and Inclination, &c. Conduce only to the former of these ends. The exacttime of the Beginning, Middle, and End of Eclipses, as also in _Total_ones, the Beginning and End of _Total_ darkness, is useful for both ofthem. But because in Observations made by the _bare_ Eye, these timesconsiderably differ from those with a _Telescope_; and, because the_Beginning_ of Eclipses, and the _End_ of _Total_ darkness, are scarce tobe observed exactly, even with Glasses (none being able clearly todistinguish between the _True_ Shadow and _Penumbra_, unless he hath seen, for some time before, the Line, separating them, pass along upon theSurface of the Moon;) and lastly, because in small {389} _Partial_Eclipses, the Beginning and End, and in _Total_ ones of short continuancein the Shadow, the Beginning and End of _Total_ darkness, are unfit fornice Observations, by reason of the slow change of _Apparences_, which the_Oblique_ Motion of the Shadow then causeth. For these reasons I shallpropound a _Method_ peculiarly design'd for the Accomplishment of the_Geographical_ end in Observing Lunar Eclipses, free (as far as ispossible) from all the mentioned Inconveniences. For, _First_, It shall not be practicable without a Telescope. _Secondly_, The Observer shall alwayes have opportunity before his principalObservation, to note the Distinction between the _True Shadow_ and the_Penumbra_. And, _Thirdly_, It shall be applicable to those Seasons of theEclipse, when there is the suddenest Alteration in the _Apparences_. To satisfie all which intents, Let there be of the Eminentest _Spots_, dispersed over all Quarters of theMoons Surface, a select number generally agreed on, to be constantly madeuse of, to this purpose, in all parts of the World. As, for Example, those, which _M. Hevelius_ calleth, { Sinai. { { Æthna. { Besbicus. { Mæotis. Mons { Insula. { Palus { { Porphyrites. { Creta. { Maræotis. { Lacus Niger Major. { Serorum. Let in each _Eclipse_, not all, but (for instance) three of these _Spots_, which then lie nearest to the _Ecliptick_, be exactly observed, when theyare first touch'd by the _True_ Shadow, and again, when they are justcompleatly entred into it, and (if you please) also in the _Decrease_ ofthe Eclipse, when they are first fully clear from the _True_ Shadow: Forthe accurate determinations of which moments of time (that being in thisbusiness of main importance) let there be taken _Altitudes_ of remarkable_Fixed Stars_ on this {390} side of the _Line_, of such, as lie between the_Æquator_ and _Tropick_ of _Cancer_; but _beyond_ the _Line_, of such, asare situate towards the other _Tropick_; and in all places, of such, as atthe time of Observation, are about 4. Hours distant from the _Meridian_. * * * * * _An Account of some Observations, lately made in _Spain_, by His Excellencythe _Earl of Sandwich_. _ The Right Honourable the _Earl of Sandwich_, as he appears eminent indischarging the Trust, his Majesty hath reposed in him, of AmbassadorExtraordinary to the King of _Spain_; so he forgets not in the midst ofthat Employment, that he is a Member of the _Royal Society_; but does fromtime to time, when his weighty State-Negotiations do permit, imploy himselfin making considerable Observations of divers kinds, both _Astronomical_and _Physiological_; and communicateth the same to the said _Society_; asfor instance, lately, what he has observ'd concerning the _Solar Eclipse_in _June_ last, the Suns height in the Solstice, and also the Latitude of_Madrid_, esteeming by the Suns Altitude in the _Solstice_, and by otherMeridian Altitudes, the _Latitude_ of _Madrid_ to be 40 deg. 10 min; whichdiffers considerably from that assigned by others; the General Chart of_Europe_ giving to it 41 deg. 30 min. The General Map of _Spain_, 40 deg. 27 min. A large Provincial Map of _Castile_, 40 deg. 38 min. To these particulars, and others formerly imparted, his Excellency ismaking more of the same nature; and particularly those of the Immersion ofthe _Satellites_ of _Jupiter_. We must not omit mentioning here, what he hath observed of _Halo_'s aboutthe _Moon_; which he relates in these words; _Decemb. _ 25. _Old Style_, 1666. In the Evening, here (vid. At _Madrid_)was a great _Halo_ about the Moon, the _Semidiameter_ whereof was about 23deg. 30 min. _Aldebaran_ was just in the _North-east_ part of the _Circle_, and the two Horns of _Aries_ just enclosed by the _South-west_ of the_Circle_, the Moon being in the _Center_. I note this the rather (_saithhe_) because five or six years ago, vid. _Novemb. _ 21. _Old Style_, 1661. An hour after Sun-set, I saw a great _Halo_ about the Moon of the same_Semidiameter_, {391} at _Tangier_, the Moon being very near the sameplace, where she was now. * * * * * _Extract of a Letter, lately written by Mr. _Nathaniel Fairfax_ to the_Publisher_, containing Observations about some _Insects_, and theirInoxiousness, &c. _ The Ingenious Author of this Letter, as he expresses an extraordinarydesire to see the _Store-house_ of _Natural Philosophy_, more richlyfraughted (a Work begun by the single care and conduct of the ExcellentLord _Verulam_, and prosecuted by the Joynt-undertakings of the _R. Society_) so he very frankly offers his Service in contributing some of hisObservations, and begins in this very Letter to perform his Offer. For, Having taken notice of what was publisht in _Numb. 9. P. 161_. Out of the_Italian_ Philosopher _Redi_, vid. That Creatures, reputed Venomous, areindeed no Poysons, when swallow'd, though they may prove so, when put intoWounds: He, for confirmation thereof, alledges Examples of several Personswell known to him (himself also having been an Eye-witness to some suchExperiments) who have frequently swallow'd _Spiders_, even of the rankestkind, without any more harm than happens to Hens, Robin-red-breasts, andother Birds, who make Spiders their daily Commons. And having made mentionof some men, that eat even _Toads_, he adds, that though a Toad be not aPoyson to us in the whole; yet it may invenome outwardly, according to someparts so and so stirr'd; an instance whereof he alledges in a Boy, whostumbling on a Toad, and hurling stones at it, some Juyce from the bruisedToad chanced to light upon his Lips, whereupon they swell'd, each to thethickness of about two Thumbs: And he neglecting to use, what might beproper to restore them, they have continued in that mishapen size eversince; the ugliness whereof, when the Relator saw, gave him occasion toinquire after the cause of it, which thereupon he understood to be, as hasbeen recited. On this occasion, the same Gentleman relates, that once seeing a Spiderbruised into a small Glass of Water, and that it tinged {392} it somewhatof a Sky-colour, he was, upon owning his surprise thereat, informed, that adozen of them being put in, they would dye it to almost a full _Azure_. Which is touch't here, that, the Experiment being so easie to make, it maybe tried, when the season furnishes those Insects; meantime, it seems notmore incredible, that this Creature should yield a Sky-colour, when put inwater, than that _Cochineel_, which also is but an Insect, should afford afine _red_, when steep'd in the same Liquor. * * * * * _An Account Of Some Books. _ _I. _ Le Tome troisieme et dernier des Lettres de _M. DES-CARTES_. As the two first _Tomes_ of M. _Des-Cartes_ his Letters, contain Questions, for the most part of a _Moral_ and _Physiological_ Nature, proposed to, andanswer'd by him; so _this_ consists of the Contests, he had upon severalSubjects with divers Men eminent in his time. To pass by that sharp Contest, he was engaged in by some Professors ofDivinity at _Utrecht_, who endeavoured to discredit his Philosophy, asleading to Libertinisme and Atheisme, notwithstanding he made it so muchhis business, as to assert the Existence of a Deity, and the Immortality ofa Soul: We shall take notice of what is more to our purpose, _vid. _ theDifferences, he had touching his _Dioptricks_ and _Geometry_. As for his _Dioptricks_, though a great part of the Learned World have muchesteem'd that Treatise, as leaving little to be said after him upon thatSubject; yet there have not been wanting Mathematicians, who have declaredtheir disagreement from his Principles in that Doctrine. The first of themwas the Jesuit _Bourdin_, Mathematick Professor in the Colledg of_Clermont_ at _Paris_; but this difference was soon at an end. A second wasMr. _Hobbs_, upon whose account he wrote several Letters to _Mersennus_, containing many remarks conducing to the Knowledge of the Nature of_Reflection_ and _Refraction_. But the Person, that did most learnedly andresolutely attack the said _Dioptricks_, was Monsieur _Fermat_, {393}writing first about it to _Mersennus_, who soon communicated his Objectionsto M. _Des-Cartes_, who failed not to return his Answer to them. But_Fermat_ replied, and _Des-Cartes_ likewise; and after many reciprocations, in which each party pretended to have the advantage, the matter rested;until M. _Fermat_ taking occasion to write afresh of it to M. _De laChambre_, several years after _Des-Cartes_'s death, upon occasion of aBook, written M. _De la Chambre_, _Of Light_; discoursed with this new_Author_ after the same rate, as he had done before with _Des-Cartes_himself, and seemed to invite some-body of his friends, to re-assume theformer contest. Whereupon M. _Clerselier_ and M. _Rohault_ took up theGantlet, to assert the Doctrine of the deceased Philosopher, exchangingseveral Letters with M. _Fermat_, all inserted in this _Tome_, and servingfully to instruct the Reader of this Difference, and withal to elucidatemany difficult points of the Subject of _Refractions_; especially of thisparticular, _Whether the Motion of Light is more easily, and with moreexpedition, perform'd through _dense_ Mediums, than _rare_. _ Besides this, though one would think, Disputes had no place in _Geometry_, since all proofs there, are as many Demonstrations; yet M. _Des-Cartes_hath had several scufles touching that Science. As M. _Fermat_ hadassaulted his _Dioptricks_, so He reciprocally examined his Treatise _DeMaximis & Minimis_, pretending to have met with _Paralogismes_ in it. Butthe Cause of M. _Fermat_ was learnedly pleaded for, by some of his Friends, who took their turn to examine the Treatise of _Des-Carte_'s Geometry;whereupon many _Letters_ were exchanged, to be found this Book, anddeserving to be considered; which doubtless the Curious would easily beinduced to do, if Copies of this Book were to be obtain'd here in_England_, besides that one, which the _Publisher_ received from his_Parisian_ Correspondent, and which affords him the opportunity of givingthis, though but Cursory, Account of it. As to _Physicks_, there occur chiefly two Questions, learnedly treated ofin this _Volume_, though not without some heat between M. _Des-Cartes_ andM. _Roberval_. The _one_ is, touching the Vibrations of Bodies suspended inthe Air, and their Center of Agitation: about which, there is also a Letterinserted of {394} M. _Des-Cartes_ to that late Noble and Learned EnglishKnight, Sir _Charles Cavendish_. The _other_ is, whether Motion can be madewithout supposing a _Vacuum_: where 'tis represented, That, if onecomprehend well the Nature, ascribed to the _Materia subtilis_, and howMotions, called _Circular_, are made, which need not be just _Ovals_ or_true_ Circles, but are only called Circular, in regard that their Motionends, where it had begun, whatever irregularity there be in the Middle; andalso, that all the Inequalities, that may be in the Magnitude or Figure ofthe parts, may be compensated by other inequalities, met with in theirSwiftness, and by the facility, with which the parts of the _SubtleMatter_, or of the first _Cartesian_ Element, which are found every where, happen to be divided, or to accommodate their Figure to the Space, they areto fill up: If these things be well understood and considered, that then nodifficulty can remain touching the Motion of the parts of Matter _inpleno_. Besides all these particulars, treated of in this _Tome_, there occur manypretty Questions concerning _Numbers_, the _Cycloid_, the manner of_Working Glasses for Telescopes_, the way of _Weighing Air_, and many otherCuriosities, Mathematical and Physical. _II. _ASTRONOMIA REFORMATA_, Auctore _JOHANNE BAPT. RICCIOLI_, Soc. Jesu. _ For the Notice of this Book, and the Account of the Chief Heads containedtherein, we are obliged to the _Journal des Scavans_; which informs us, _First_, That the Design of this Work is, that, because several_Astronomers_, having had their several _Hypotheses_, there is found sogreat a diversity of opinions, that it is difficult thence to conclude anything certain; this Author judged it also necessary, to compare togetherall the best Observations, and upon examination of what they have mostcertain in them, to reform upon that measure the Principles of Astronomy. _Secondly_, That this _Volume_ is divided into two Parts, whereof the_First_ is composed of _Ten_ Books; in which the Author {395} considers theprincipal Observations, hitherto made of the Motion of the Planets and theFixed Stars, of their Magnitude, Figure, and other Accidents; drawingthence several Conclusions, in which he establishes his _Hypothesis_. The_second_ contains his _Astronomical Tables_, made according to the_Hypotheses_ of the First Part, together with Instructions teaching themanner of using them. _Thirdly_, That Astronomers will find in this Book many very remarkablethings, concerning the _Apparent Diameter of the Sun_ and the other Stars, the Motion of the _Libration of the Moon_, the _Eclipses_, _Parallaxes_, and _Refractions_: And that this Author shews, that there is a greatdifference between _Optical_ and _Astronomical_ Refraction, which _Tycho_and many others have confounded; undertaking to prove, that, whereas these_Astronomers_ have believed, that the remoter any Star is, the less is itsRefraction, on the contrary the Refraction is the greater, the more a Staris distant. And among many other things, he ingeniously explicates the twocontrary Motions of the Sun, from East to West, and _vice versa_, by oneonely Motion upon a _Spiral_, turning about a _Cone_. _Fourthly_, That he represents, How uneasie it is to establish surePrinciples of this Science, by reason of the difficulties of making exactObservations. So, for example, in the Observation of the _Equinox_, everyone is mistaken by so many _Hours_, as he is of _Minutes_, in the Elevationof the _Pole_, or the Diameter of the Sun, or the Refraction, or in anyother circumstance. In the Observation of the _Solstice_, the error of oneonly _Second_ causeth a mistake of an _Hour_ and an _half_: mean time 'tisalmost impossible to avoid the error of a _Second_; and even the sharpestsight will not be able to perceive it, except it be assisted with anInstrument of a prodigious bigness. For to mark _Seconds_, though Lineswere drawn as subtil as the single threds of a Silk-worms Clew, (which arethe smallest spaces to be discerned by the sharpest Eye) by the Calculationmade by this Author there would need an Instrument of 48. Feet _Radius_, since Experience shews, that there needs no more at most, than 3600. Thredsof Silk to cover the space of an _inch_. But, suppose one could have a_Quadrant_ of this bigness, who can assure himself, that dividing it into{396} 324000. Parts (for so many _Seconds_ there are in 90. _Degrees_)either in placing it, or in observing, he shall not mistake the thicknessof a single thred of Silk? He adds, that Great Instruments have theirdefects, as the small ones: For in those, that are _Movable_, if the thred, on which the Lead hangs, is any thing big, it cannot exactly mark_Seconds_; if it be very fine, it breaks, because of its great length, andthe weight of the Lead: And in the _Fixed_ ones, the greater the _Diameter_is, the less the Shadow or the Light is terminated; so that it is painfulenough, exactly to discern the extremities thereof. Yet 'tis certain, thatthe greater the Instruments are, the surer _Astronomers_ may be: Whence itis, the some _Astronomers_ have made use of _Obelisks_ of a vast bigness, to take the _Altitudes_; and Signior _Cassini_, after the example of_Egnatio Dante_, caused a hole to be made on the highest part of a Wall of95. Feet in a Church at _Bononia_, through which the beams of the Sunfalling on the Floor, mark as exactly as is possible, the height of thatLuminary. _Fifthly_, That the Author reasons for the _Immobility of the Earth_ afterthis manner. He supposes for certain, that the swiftness of the Motion ofheavy bodies doth still _increase_ in their descent; to confirm whichprinciple, he affirms to have experimented, That, if you let fall a Ballinto one of the Scales of a Ballance, according to the proportion of theheight, it falls from, it raiseth different weights in the other Scale. Forexample, A Wooden Ball, of 1½ ounce, falling from a height of 35 inches, raiseth a weight of 5. Ounces; from the height of 140 inches, a weight of20 ounces; from that of 315 inches, one of 45 ounces; and from another of560 inches, one of 80 ounces, &c. From this principle he concludes theEarth to be at Rest; for _saith he_, if it should have a Diurnal Motionupon its Center, Heavy Bodies being carried along with it by its motion, would in descending describe a _Curve Line_, and, as he shews by a_Calculus_, made by him, run equal spaces in equal times; whence itfollows, that the Celerity of their Motion would not increase indescending, and that consequently their stroke would not be stronger, afterthey had fallen thorow a longer space. {397} _III. _ANATOME MEDULLAE SPINALIS, ET NERVORUM_ inde provenientium, _GERARDIBLASII_, M. D. _ The Author shews in this little _Tract_ a way of taking the entire _MedullaSpinalis_, or Marrow of the Back, out of its _Theca_ or Bony Receptacle_without Laceration_; which else happens frequently, both of the Nervesproceeding from it, and of the Coats investing it; not to name other partsof the same. This he affirms to have been put into practice by himself, bya fine Saw and Wedge; which are to be dexterously used: and he producethaccordingly in excellent Cuts, the Representations of the Structure of thesaid _Medulla_ thus taken out, and the _Nerves_, thence proceeding; andthat of several Animals, Dogs, Swine, Sheep. He intermixes several Observations, touching the _Singleness_ of this_Medulla_, against _Lindanus_ and others; its _Original_; vid. Whether itbe the Root of the Brain, or the Brain the Root of it: its difference of_Softness_ and _Hardness_ in several Animals; where he notes, that in_Swine_ it is much softer than in Dogs, &c. He exhibits also the Arteries, Nerves, and Veins, dispersed through this_Medulla_, and inquires, Whether the _Nerves_ proceed from the _Medulla_ itself, or its _Meninx_; and discourses also of the _Principle_ and_Distribution_ of the Nerves; referring for ampler information in this andthe other particulars, to that Excellent Book of the Learned Dr. _Willis_, _De Anatome Cerebri_. {398} * * * * * _Advertisement. _ _It was thought fit to publish here_ the following _Advertisement_ of _John Evelyn_ Esquire, and that, as himself proposed it. _Viz_, Being much solicited by many worthy Persons, to publish a _Second Edition_of my Discourse and Directions concerning _Timber, &c. _ which was printedat the Command and by the Encouragement of the _R. Society_, I do humblyrequest, that if any Person have any Material, Additions or Reformations, which he thinks necessary either to the Part, which concerns theImprovement of _Forrest-Trees_, or that of _Cider_, he would be pleased tocommunicate his Notes and Directions to Mr. _H. Oldenburgh_, one of theSecretaries of the said Society, at his House in the _Palmal_ of _St. James's Fields Westminster_, with what speed they conveniently can, beforeour _Lady-day_ next, to be inserted into this intended _Edition_. * * * * * NOTE, _What was observed, _Numb. 20_. P. 364, l. 18, of the Number of_Vegetables_, _ (_vid. _ That they are about 410. ) _found in _England_; andcatalogued by Dr. _Merret_ in his _Pinax_, &c. Is to be understood only ofthe _different Kinds_ of Plants, not of the several sorts of severalPlants; for, these being comprised, the Number will amount to about 1400. _ * * * * * {399} THE_PHILOSOPHICAL TRANSACTIONS_OFTwo Years, 1665 and 1666, beginning _March_ 6. 1665. And ending with _February_ 1666; abbreviated in anALPHABETICAL TABLE:And also afterwards Digested into a more_NATURAL METHOD_. In the TABLE, the first _Figure_ signifies the _Number_ of the _Tracts:_the second, the _Page_, as it is remarked in the same. A. _Agriculture_, Head of Inquiries concerning it. _num. _ 5 _pag. _ 91. _Air. _ The weight of it in all changes, by wind, weather, or whatever other influence observable by a standing _Mercurial Balance_, call'd a _Baroscope_, hinted in reference to M. _Hooks_ Micrography, n. 2. P. 31. Applied to particulars by Dr _Beale_, 9. 153. With additions, 10. 163. Described with observables relating to an Earth-quake about _Oxford_ by Dr. _Wallis_, 10. 167. Mr. Boyle's remarks on the same, 11. 181. The _Wheel-Baroscope_ improved and delineated by M. _Hook_, 13. 218. Another Balance of the Air contrived by M. _Boyle_, and call'd _Statical_, by which the former may be exactly stated and examin'd for many particular applications, 14. 231. _Anatome_, see _Flesh_, _Blood_, _Animals_, _Lungs_, _Petrification_, _Taste_; item, _Steno_, _Graeff_, _Bellinus_, _Redi_, in the _Liste of Books_. _Animals_, one may live by the blood of another, the whole mass of his own blood being drawn out, and the blood of another infus'd in the mean time, 20. 353. See _Bloods Tranfusion_. The Generation and Functions of Animals deduced by Mechanical principles, without recourse to _substantial form_, 18. 325. See _Honor. Fabri. _ & n. 20. P. 365. See also _Guarini_. _Artificial Instruments_ or _Engins. _ To weigh _air_, see _Baroscope_, or rather _Air_. To discern drought or moisture of the Air, see _Hygroscope_. N. 2. P. 31. Appliable in the observation of _Tydes_, 17. 300. _Thermometers_, to measure degrees of heat and cold, 2. 31. Described, 10. 166. Applied in the examination of _Tydes_, 17. 300. An Instrument for graduating _Thermometers_, to make them _Standards_ of heat and cold, 2. 31. A new Engine for grinding any Optick Glasses of a Sphærical figure, 2. 31. To measure the Refractions of Liquors of all kinds, for establishing the Laws of Refraction, 2. 32. To break the hardest Rocks in _Mines_, 5. 82. To try for _fresh_ waters at the bottom of the _Seas_, 9. 147. To find the greatest depths in the Sea, 9. 147. The _Engin_ for fetching up fresh water defended by Explication, 13. 228. Huge _Wheels_, and other Engins for _Mines_, 2. 23. By the fall of water to blow wind, as with Bellows, 2. 25. {400} _Astronomical_ Remarks of a _New Star_ seen by _Hevelius_ in _Pectore Cygni_, which he supposeth to be the same, which _Kepler_ saw A. 1601. And continued until 1602. And was not seen again until 1662. And then almost always hiding it self till 24. _Nov. _ 1666. _That_, seen by _Kepler_ was of the third magnitude; this now, of the sixth or seventh. Q. Whether it changes place and magnitude, 19. 349. The _Scheme_, 21. 372. A _New Star_ in _Collo Ceti_, observ'd from 1638, to 1664, 1665, 1666. With its vicissitudes and periods, and causes of change, open'd by _Bullialdus_, who conceives the bigger part of that round body to be obscure, and the whole to turn about its own Center, 21. 382. Another _New Star_ call'd _Nebulosa_ in _Cingulo Andromedæ_, seen when the Comet appear'd 1665. Observ'd by the said _Bullialdus_ to appear and disappear by turns, _ibid. _ 383. A method for observing the _Eclipses of the Moon_, free from the common Inconveniences, by M. _Rook_, 22. 387. B. _Baroscope. _ See _Air_ and _Artificial_ Instruments. _Blood. _ The new Operation of _Transfusing_ blood into the veins, out of one Animal into another; with considerations upon it, 20. 353. The first Rise of this Invention, 7. 208. The Success, 19. 352. Proposals and Queries, for the improvement of this Experiment, by M. _Boyle_, 22. 385, 386. Little Blood-letting in _China_, 14. 249. Blood found in some mens veins like Milk, or of the colour of Milk, 6. 100. Again p. 117. 118. And again 8. 139. A _Bolus_ in _Hungary_ good as _Bole Armenick_, 1. 11. The _Bononian Stone_, see _Light_ or _Stone_, 21. 375. _Books_ abbreviated, or recited: Laur. _Bellinus_ de Gustùs Organo novissimè deprehenso, 20. 366. Abbrev. Gerh. _Blasii_ Anatome Medullæ Spinalis & Nervorum inde procedentium, abbrev. 22. 397. Mr. _Boyle_ of Thermometers and History of Cold, abbrev. 1. 8. More 3. 46. ---- His _Hydrostatical Paradoxes_ abbrev. 8. 145. More largely 10. 173. ---- His _Origin of Forms_ and _Qualities_, 8. 145. Abbreviated 11. 191. Monsieur _de Bourges_ his Relation of the Bishop of _Beryte_ his Voyages in _Turky_, _Persia_, _India, _ abbrev. 18. 324. _Bullialdi_ Monita duc, abbrev. 21. 381. See sup á _Astronomy_. _Des Cartes_ his Third Volume of _Letters_, 22. 392. _De la Chambre_'s Causes of the inundation of the Nile, abbr. 14. 251. _Cordemoy_ of the difference of Bodies and Souls, or Spirits, and their operation upon one another, abbrev. 17. 306. _Euclidis_ Elementa Geometrica novo ordine de nonstrata, 15. 261. Hon. _Fabri_ Soc. Jes. Tract. Duo 1. De Plantis & Genet. Animalium. 2. De Homine; abbreviated, 18. 325. _Felibien_ of the most excellent Paintings, 21. 383. Catalogue of _Fermats_ Writings, and his character, 1. 15. _De Graeff_, de Succi Pancreatici natura & usu, abbrev. 10. 178. _Guarini_ Placita Philosophica, abbreviated, 20. 365. _Hevelius_'s Prodromus Cometicus, abbrev. 6. 104. His _Descriptio Cometica cum Mantissa_, abbrev. 17. 301. _Hobbes_ de Principiis & Ratione Geometrarum, described, 14. 193. Animadverted upon by Dr. _Wallis_, 16. 289. _Hooks_ Micrographical and Telescopical Observations, Philosophical Instruments and Inventions, abbr. 2. 29. _Kircher_'s Mundus Subterraneus, abbrev. 6. 109. _Lower_'s Vindication of Dr. _Willis_ de Febribus, 4. 77. _Meret_'s Pinax Rerum Naturalium Britannicarum, continens Vegetabilis, Animalia & Fossilia, in hac insula reperta, inchoatus; abbr. 20. 364. _Parker_'s Tentamina Physico Theologica, abbrev. 18. 324. _Redi_ an Italian Philosopher, of Vipers, abbrev. 9. 160. _Ricciolo_'s Astronomia Reformato, Volumen quartum abbrev. 22. 394. _Smith_ of K. _Solomon_'s Pourtraicture of Old Age, 14. 254. {401} _Stetonis_ de Musculis & Glandulis observatium Specimen; cum duabus Epistolis Anatomicis, abbrev. 10. 176. _Sydenhami_ Methodus Curandi Febras, abbrev. 12. 210. _Thevenot's_ Relation of curious Voyages, with a Geographical description of _China_, abbr. 14. 248. The English _Vineyard_ vindicated, 15. 262. Isaac _Vossius_ de Origine Nili, abbreviated, 17. 304. _Vlug-Beig_ great Grand-child to the famous _Tamerlane_, his Catalogue of fix't Stars, with their Longitudes, Latitudes, and Magnitudes, taken at _Samarcand_, A. 1437. Translated out of a _Persian_ M. S. By M. _Hyde_, Keeper of the Bodleian Library, 8. 145. The _Burning_ Concave of _M. De Vilette_ in _Lyons_, burning and melting any matter (very few excepted. ) What, and How, and at what distance. The proportion; and compared with other rare burning Concaves, 6. 96. C. In _China_ very ancient Books found of the nature and vertues of Herbs, Trees and Stones, 14. 249. The Root _there_ called _Genseng_, very restorative and cordial, recovering agonizing persons, sold there each pound for three pounds of silver, 14. 249. _China_ Dishes how made there, _ibid. _ A way found in _Europe_ to make _China_-Dishes, 7. 127. _Chymists_ in _China_ pretend to make Gold, and promise Immortality, 14. 249. _Cold_, see M. _Boyles_ History, abbrev. More Inquiries, and some answers touching _Cold_, 19. 344. How _Cold_ may be produced in hottest Summers by _Sal Armoniack_, discovered by M. _Boyle_, 15. 255. Some suggestions see remedies against _Cold_, by D. _Beale_, 21. 379. _Comets. _ The motions of the Comet of _Decemb. _ 1664. Predicted, 1. 3. _Cassini_ concurs; 2. 17. _Auzout_, who first predicted the motion, reflects upon _Cassini_, 2. 18. And predicts the motions of the second Comet of _March, April_ 1665. N. 3. 36. Controversies and Discourses, some at large, concerning _Comets_, n. 1. P. 3. N. 2. P. 17, 18. N. 3. P. 36. N. 6. P. 104. N. 9. P. 150. N. 17. P. 301. Many considerables abbreviated, n. 6. P. 104. N. 17. P. 301. D. _Damps_ in Mines pernicious, 3. 44. And how killing, _ibid. _ _Directions_ for Seamen bound for far Voyages, by M. _Rook_, 8. 140. Mr. _Boyles_ Inquiries, 18. 315. Philosophical _Directions_ or Inquiries for such as Travel into _Turky_, 20. 360. _Directions_, or general Heads for a natural History of a Countrey, by M. _Boyle_, 11. 186. _Directions_ or Inquiries concerning _Mines_, by the same, 19. 330. _Diamonds_ where, and how the fairest are discover'd, 18. 327. E. The _Earthquake_ about _Oxford_, Anno 1665. Described by D. _Wallis_, 10. 181. By M. _Boyle_, 11. 179. Noting the Concomitants thereof by _Baroscope_ and _Thermometer_. The _Earth_'s Diurnal motion prov'd by the motion of the Comets, 1. 6. & 7. Especially by the slow motion of the second Comet, 3. 39. See M. _Auzout_, confirm'd by M. _Hevelius_, 6. 105. Confirm'd also by the Tydes at Sea, 16. 265. The _Eclipse_ of _June_ 22, 1666. Accurately observ'd at _London_, 17. 245. At _Madrid_, _ibid. _ at _Paris_, 17. 246. At _Danizick_, drawn in accurate Cuts, n. 19. 347. N. 21. P. 369. _Elephants:_ How to escape, or to combat with them, 18. 328. _Eeles_ discover'd under Banks in Hoar-Frosts, by the Greens of the Banks approaching, 18. 383. F. The _Fleshy_ parts of the Body which are usually reputed, and do seem void of Vessels, are argued to be full of Vessels, by D. _King_, 18. 316. _Friction_ and sometimes _Touch_, how sanative, by several Examples, 12. 206. _Frictions_ much used by Physitians in _China_ with good success, 14. 249. {402} G. _Geometricians_ censur'd by M. _Hobbs_, 14. 153. Defended by D. _Wallis_, 16. 289. The method of teaching _Geometry_ reform'd, 15. 261. See _Euclidis Elementa novo ordine_, among the Books. I. _Inquiries_, see Directions, suprá. _Ice_ and Snow how to be preserv'd in Chaffe, and how Snow-houses are made in _Livorn_, 8. 139. _Insects_, in swarms pernicious in some Countries; the cause of them, and what Remedies, 8. 139. Some _Insects_, commonly believed poysonous, not so, by M. _Fairfax_, 22. 391. To find the _Julian_ period by a new and easie way, 18. 324. _Jupiter_'s Rotation by degrees discover'd in _England_ and _Italy_, n. 1. P. 3. N. 4 p. 75. N. 8. P. 143. N. 9. P. 173. N. 12. P. 209. N. 14. P. 245. K. _Kermes_, how gather'd and used for Coloration, describ'd with many considerables, 20. 362. L. _Light_, to examine what figure or celerity of motion begetteth or increaseth Light or Flame in some Bodies, by D. _Beale_, 13. P. 226. _Shining_ Worms found in Oysters, 12. 103. The Bononian Stone duly prepar'd continues _light_ once imbibed above any other substance yet known amongst us, 21. 375. The loss of the way of preparing the same for shining, feared, _ibid. _ _Longitudes_ at Sea, how to be ascertain'd by Pendulum-Watches, 1. 13. _Lungs_ and Windpipes in Sheep and Oxen strangely stopt with Hand-Balls of Grass, 6. 100. M. _Marbles_, that a liquor may be made to colour them, piercing into them, 7. 125. _Mars_, by what steps and degrees of diligence discover'd to be turbinated, both in _England_ and _Italy_. Compare n. 10. P. 198. And n. 14. 239, 242. See the Schemes there. _May-dew_ examin'd by various Experiments, by M. _Henshaw_, 3. 33. _Mechanical_ Principles in a Geometrical method, explicating the nature or operation of Plants, Animals, 8. 325. _Medicins_ in _China_ consist for the most part of Simples, Decoctions, Cauteries, Frictions, without the use of Blood-letting, 14. 249. The _Physitians_ there, commended for speedy Cures, and easie, _ibid. _ _Mediterranean Sea_, whether it may be join'd with the Ocean, debated, 3. 41. _Micrography_ epitomized, 2. 27. M. _Auzout_'s Objections to a part of it; vid. The new way of grinding Spherical Glasses by a Turn-lath, 4. 57. M. _Hooks_ answer thereunto, 4. 64. Both at large. _Mercury_-Mines in _Friuli_, and the way of getting it out of the earth, 2. 21. _Mineral_ Inquiries, see Directions, Engins, Artificial Instruments. _Mineral_ at Liege yielding Brimstone and Vitriol; and the way of extracting them, 3. 35. How Adits and _Mines_ are wrought at Liege, 5. 79. A Stone in _Sueden_ yielding Sulphur, Vitriol, Allum and Minium, and how, 21. 375. See _Kircher_'s Mundus Subterraneus abbr. 6. 109. _Monsters_, a Calf deform'd, and a great stone found in a Cows womb, n. 1. 10. A _Colt_ with a double eye in one place, 5. 85. _Moons_ Diameter how to be taken, and why increased in the Solar Eclipse of _Jun. _ 22. 1666. N. 2. P. 373. See _Planets_. What discoverable in the _Moon_, and what not. _Moons Eclipses_ how to take without inconvenience, 22. 387. _Mulberry-Trees_ how to be cut low, and easie to be reach'd, for relief of Silk-worms, in _China_, 14. 249. In _Virginia_, 12. 202. See Silk. N. _Nile's_ Inundations, the cause attributed to _Niter_, by _Dela Chambre_; opposed by _Vossius_. See both in the _List of Books_, 14. 251. And 17. 304. The _North-Countries_ of _Poland_, _Sweden_, _Denmark_, &c. Are warm'd by the influence of the _Royal Society_, 19. 344. {403} O. _Ocean_, what Seas may be joined with it, 3. 41. _Opticks_, Campani's Glasses do excell Divini's; 'tis easie by them to distinguish people at four Leagues distance, 2. 131. And 12. 209. What they discover in _Jupiter_ and _Saturn_, 1. 1. And 2. The proportions of Apertures in Perspectives reduced to a Table by M. _Auzout_, 4. 55. Animadverted upon by M. _Hook_, 4. 69. How to illuminate Objects to whatsoever proportion, proposed by M. _Auzout_, 4. 75. _Hevelius_, _Hugenius_, and some in _England_, endeavour to improve Optick Glasses, 6. 98. Seigneur _Burattini_'s advance in the same inquired after, 19. 348. Some answer to it from _Paris_, 22. 374. _Divini_ makes good Optick Glasses of Rock-chrystal, that had veins (_if he mistook not somewhat else for veins_) 20. 362. To measure the distance of Objects on earth by a Telescope, undertaken by M. _Auzout_, and others of the _Royal Society_, 7. 123. How a Telescope of a few feet in Diameter may draw some hundreds of feet, 7. 127. How a Glass of a small convex-sphere may be made to reflect the Rayes of Light to a _Focus_ at a far greater distance than is usual, 12. 202. P. _Parsley_, to make it shoot out of the ground in a few hours, see _Hon. Fabri_ 18. 325. _Pictures_, a curious way in _France_ of making lively Pictures in Wax, and Maps in a low relieve, 6. 99. The cause why _Pictures_ seem to look upon all Beholders, on which side soever they place themselves, 18. 326. Ancient _Paintings_ compar'd with the Modern, and a judgment of the _Paintings_ in several Ages, their perfections, and defects, see M. _Felibien_, 21. 383. _Petrification_, in the wombs of Women, 18. 320. In a Calf in the Cows womb, 1. 10. _Stones_ found in the heart of the Earl of _Belcarris_, 5. 86. Part of an Elm by incision, or otherwise, _petrified_ a foot above the root and ground, 19. 329. Wood _petrified_ in a sandy ground in _England_; and of a Stone like a Bone or Osteocolla, 6. 101. A _Stone_ of excellent vertues found in the head of a Serpent in the _Indies_, 6. 102. The causes of _Petrification_ inquired, 18. 320. _Planets_, See _Jupiter, _, _Mars_, _Saturn_, _Sun_, _Moon_; which are turbinated, and which not, 8. 143. To find the true distances of the Sun and Moon from the earth, 9. 191. _Physitians_ of _China_ commended, see _Medecins_. _Preservation_, to preserve small Birds taken out of the shell, or other _Fætus_'s, for discoveries, 12. 198. _Pulses_ of the Sick how diligently, and to what good purposes observ'ed in _China_, 14. 249. R. _Rainbows_ strangely posited, 13. 219. _Raining_ of Ashes, and how, 21. 377. _Rice_ prospers best in watery places, see _Marishes_, 18. 328. S. _Salamander_, how it extinguishes fire, and feeds by licking _Indian_ earth, 21. 377. _Salt_ by excessive use stiffens, and destroys the body, 8. 138. _Salt-Springs_, see _Springs_. _Salt-Peeter_ how made in the _Mogols_ Dominions, 6. 103. The proportion of _Salt_ in best Salt-Springs; and what grounds or signs of best _Salt_, 8. 136. _Sea-fluxes_, the cause proposed by way of a new Theory, by Dr. _Wallis_, 16. 263. See _Tydes_. _Seas_, whether they may be united, 3. 41. _Silk-Worms_ and _Silk-Trade_ sollicited, 5. 87. And 2. 26. And 12. 201. _Snakes_, how they differ from Vipers, 8. 138. _Rattle-Snakes_, how sometimes kill'd in _Virginia_, 3. 43 and 4. 78. _Snow-houses_ directed, and how to preserve Ice and _Snow_ in Chaffe, 8. 139. _Springs_, of peculiar note, n. 7. 127. N. 8. 133. 135. And 136. N. 18. 323. {404} T. _Taste_, the Organ and Nature of it, 20. 366. _Thunder_ and Lightning, the Effects examined, n. 13. 222. N. 14. 247. _Tydes_, the causes proposed, 16. 263. See a further examination by a severe History of Tydes, Winds, and other circumstances directed, n. 17. N. 18. N. 21. _Trees_ of Oak how found under-ground in Moors or Marishes, 18. 323. _Thee_, in _China_ and what; how exchanged there for dried leaves of Sage by the _Dutch_, 14. 249. W. _Whale-fishing_ about _Bermudas_, and _New England_, how it is performed, n. 1. 11. N. 8. 132. _Wind_, how to be raised by the fall of water, without any Bellows, 2. 25. Shewed in a draught. _Worms_, that eat holes in stones, feeding on stone, 28. 321. * * * * * {405} The more _NATURAL METHOD. _ I. A Natural History of all Countries and Places, is the foundation for solid Philosophy, _See_ Directions, Inquiries, and Instructions for a Natural History of a Countrey, n. 11. P. 186. _See_ it in part exemplified in the _History of England_, begun by Dr. _Merret_ in his _Pinax_, 20. 364. _See_ the cause of Tydes proposed by D. _Wallis_, 16. 263. _See_ the further Examination by a severe History of Tydes, Winds, and other Concomitants or Adherents, directed, n. 17. N. 18, n. 21. _See_ the Inquiries concerning the Seas, and Sea-waters, n. 18. 315. _See_ Directions for Seamen bound for far Voyages, 8. 140. _Kircher_'s Account of the Subterraneous World, 6. 109. Mr. _Boyle_'s Directions and Inquires touching Mines, 19. 330. Philosophical Directions and Inquiries for such as Travel into _Turky_, n. 20. 300. The Relation of M. _de Bourges_, 18. 324. M. _Thevenots_ Relation of divers curious Voyages, &c. More particularly of _China_, 24. 248. The causes of the inundation of the _Nile_, disputed by _Dela Chambre_ and _Vossius_. In the _List of Books_. _See_ Mr. _Boyle_'s Mechanical Deductions, and Chymical Demonstrations of the _Origine of Forms and Qualities_, 11. 191. _See_ the Application of these Mechanical Principles more particularly to the Nature, Operation, and Generation of Plants and Animals, and to our humane Contexture, in a Geometrical method, by _Hon. Fabri_, 18. 325. _See_ Mr. _Boyle_'s History of Cold and Thermometers, n. 1. P. 8. N. 3. P. 46. The History of Winds and Weather, and all changes of the Air (especially in relation to the weight) observable by the Baroscope, n. 9. N. 10, n. 11. _Light_, some special search into the causes, and some peculiar Examples. _See_ above in _Light_. _Petrification_ sollicited, see Petrification, Stone. The Earths Diurnal Rotation, see Earth _suprá_. Adventurous Essayes in Natural Philosophy, see _Guarini_, 20. 365. Earthquakes, and their Concomitants observed, n. 10. N. 11. The effects of Thunder and Lightning, examin'd, see _Thunder_, n. 13. 222. N. 14. 247. The raining of Ashes and Sand at great distance from the Mount _Vesuvius_, see _Raine_, 21. 377. Springs, and Waters of peculiar Note, see _Springs_. Insects in Swarms how begotten; pernicious, and how destroyed, 8. 137. Monsters, or Irregularities in Nature. The _Calf_, _Colt_, suprá. Four Suns at once, and two strange Rainbows, 13. 219. _See_ the statical position and tendency or gravitation of Liquids, in M. _Boyle_'s _Hydrostatical Paradoxes_, 8. 145. _See_ in M. _Hooks_ Micrography, a History of minute Bodies, or rather of the minute and heretofore unseen parts of Bodies; it being a main part of Philosophy, by an artificial reduction of all gross parts of Nature to a closer inspection. _Medicinals_, see Medicine. Physitians, _China_. Friction, Dr. _Sydenham_. Dr. _Lower_, Friction, _suprá. _ n. 4. 77. N. 12. 206. _Anatome_, see _Steno de Musculis & Glandulis_. How a juyce in the stomack dissolves the shells of Crafishes, _ibid. _ Graeff _de Succo Pancratico_; that Flesh hath Vessels, n. 18. 316. Blood degenerated to resemble milk, n. 6. 117. The Transfusion of blood, 20. 353. The organ and nature of _Taste_, 20. 366. {406} _Salt_ too much stiffens and destroys the Body, 8. 138. II. _Singularities_ of Nature severely examin'd. The ordering of _Kermes_ for Color. N. 20. 362. How the _Salamander_ quencheth Fire, and lives by licking the Earth. N. 21. 377. Whether Swallows do lie under water in Winter, and revive in Summer? n. 19. 350. Whether the _Hungarian Bolus_ like the _Armenus_? 1. 11. _Rattle-Snakes_ how kill'd in _Virginia_, 3. 43. _Snakes_ and Vipers how they differ, see _Snakes_ above. The Qualities and Productions of _May-dew_, 3. 1. Damps in Mines how they kill, 3. 44. Teeth growing in aged persons, 21. 380. Steams and Expirations of the Body how stopp'd; and the stoppage dangerous or mortal, 8. 138. Shining Worms in Oysters, 12. 203. III. _Arts_, or Aids for the discovery or use of things Natural. _See_ Artificial Instruments in the _Table_. Agriculture, _see_ the Inquiries, 5. 91. English Vineyards vindicated, see in the _Catalogue of Books_. Geometry, see _Euclid_ methodized for Facility, _Fermat: in the Catalogue of Books. _ Astronomy, see Astronomical Remarks. _Bullialdus_, _Hevetius_, _Comets_, _Planets_, _Saturn_, _Jupiter_, _Mars_, _Sun_, _Moon_, _Eclipses_. Opticks _see_ that Head in the _Table_. Picture, _see_ that Head in P. And _Felibien_ in the _Catalogue of Books_. How to paint Marbles within, _see_ the Head _Marble_. _Pendulum_ Watches to ascertain _Longitudes_ at Sea, 1. 13. Whale-fishing about _Bermudas_, 1. 11. And 8. 132. Silk-trade sollicited in _France_, _Virginia, _ see _Silk_ in the _Table_. Eeles how to be found in Frosts, 17. 323. Winds raised to blow by the fall of water without Bellows, 2. 25. Shew'd in a _Cutt_. Elephants enraged, how to escape or subdue, 18. 328. Seas and vast waters, whether they may be united to the main Ocean, 3. 41. To proportion the distance necessary to burn Bodies by the Sun; and shewing, why the Reflections from the Moon and other Planets do not burn, 4. 69. The Art of making _Salt-Peeter_, as practised in the _Mogols_ Dominions, 6. 103. To make _China_-Dishes, 14. 249. Expected from Seigneur _Septalio_ to be made in _Europe_, 7. 127. To convey blood of one Animal, or other Liquors, into the blood of another Animal, 20. 353. To preserve Ice and Snow by Chaffe, 8. 138. To preserve Ships from being Worm eaten, 11. 190. To preserve Birds taken out of the Eggs, or other small _Fætus_'s, for Anatomical, or other Discoveries, 12. 199. To allay the heat in hottest Summer, for Diet or Delight, 15. 255. Remedies against extream Cold suggested, 21. 379. Trees of Oak as black as Ebony discover'd, and taken up out of Moors and Marshes in draughty weather, 11. 323. * * * * * _Note, _ That though in this last Head there is repeated the _Transfusion_ of Blood, because the Operation is an Art requiring diligence, and a practised handto perform it for all advantagious Discoveries, and so to be distinguish'dfrom the _Anatomical_ Account; yet that there is not affected noise andnumber, may well appear by reviewing and comparing the particulars of_Artificial Instruments_ in the {407} _Table_, where sometimes one Engin orInstrument may minister Aid to discover a large branch of Philosophy, asthe _Baroscope_, an _Optick Glass_, &c. And very particularly M. _Rook_'s directions for Seamen, which specifiesInstruments, may hereunto belong. And sometimes in one of the Discourses herein mention'd, and abbreviated, there are almost as many Artificial Inventions, as Experiments; as in Mr. _Boyle_'s Hydrostatical Experiments: Besides all the Chymical Operations, recited in the _Treatise_ of the _Origine of Forms_, &c. [Greek: Ouk en tôi megalôi to eu, all' en tôi eu to mega. ] * * * * * ERRATA. Pag. 392. Lin. 23. Blot out, _as_. Ibid. Lin. 24. Read _of the Soul_. * * * * * FINIS. {408} * * * * * In the _SAVOY_, Printed by _T. N. _ for _John Martyn_, and _James Allestry_, Printers to the_Royal Society:_ And are to be sold at their Shop without _Temple-Bar_, andin _Duck-lane_, 1667. * * * * * * * * * * Corrections made to printed original. Page 6, "But that, which he judgeth most remarkable": 'rewarkable' inoriginal. Page 29, "the strange Phænomena of Glass-drops": 'Grass-drops' in original. Page 33, "Of the Mineral of Liege": 'Leige' in original. Page 103, "by the feet of People they tread it": 'traed' in original. Page 104, "sell us a Maon of 6 pounds": 'a Moan' in original. Page 109, "Of the Mundus Subterraneus of Athanasius Kircher": 'Athansius'in original. Page 110, "the Earth, its Heterogeneous Nature": 'Mature' in original. Page 110-1, "the manifold Productions made therein": 'Produ-actions' inoriginal, across page-break; the catch-word is 'ctions'. Page 111, "Secondly, of the Transformation of Juices": 'Transforma-on' inoriginal, across line-break. Ibid. , "little Fishes, and Plants are Intombed therein": 'Planets' inoriginal(!). Page 115, "A Relation of strange Earth-quakes": 'Eath-quakes' in original. Page 121, "or that none of them burn at this time": 'or or' across twolines in original. Page 141, "together with all the Accidents": 'Ac-dents' in original, acrosspage-break; the catch-word is 'cidents'. Page 142, "take exact care to observe the Trade-Winds": 'Trade-Wines' inoriginal. Page 148, "1/16 at the bottom in diameter": 'the the' in original. Page 172, "Jupiter turns about his Axis in 9. Hours 56. Minutes": '9. Dayes56. Minutes' in original (which contradicts the rest of the paragraph). Page 228, "and by better Microscopes": 'bet-bet' in original, acrossline-break. Page 243, para. 5. Numbered 4. In original. Ibid. , "very distant from one another": 'anothe' in original. Page 297, "that some understanding Persons at London, or Greenwich, butrather nearer the Sea, ": 'that' and 'Sea, ' transposed in original (firstwords of successive lines). Page 315 (Sidenote), "the Differences of Gravity he might meet with":'Garvity' in original. Page 315, "from the greater or lesser Proportion of Salt": 'gteater' inoriginal. Ibid. "the Stones, Minerals and Vegetables to be found there": 'Vetegables'in original. Page 315, "the Deity, which we worship": 'Diety' in original. Page 335, para. 35. Numbered 75. In original. Page 364, "PINAX Rerum Naturalium BRITANNICARUM": 'BRITANIARUM' in original(cf. Contents page & volume index). Page 376, "carry into the Work-house": 'Work-honse' in original. Page 379, "by Art, or Mechanical contrivance": 'contri-trivance' inoriginal, across line-break. Page 381, "the Canini of the left Cheek": 'Check' in original. Page 400, Astronomical Remarks of a New Star: "which Kepler saw A. 1601. ":'1661' in original (the remaining dates in this index entry do not wellmatch the article).