AUTOBIOGRAPHY OF SIR GEORGE BIDDELL AIRY, K. C. B. , M. A. , LL. D. , D. C. L. , F. R. S. , F. R. A. S. , HONORARY FELLOW OF TRINITY COLLEGE, CAMBRIDGE, ASTRONOMER ROYAL FROM 1836 TO 1881. EDITED BY WILFRID AIRY, B. A. , M. Inst. C. E. 1896 PREFACE. The life of Airy was essentially that of a hard-working, business man, and differed from that of other hard-working people only in thequality and variety of his work. It was not an exciting life, but itwas full of interest, and his work brought him into close relationswith many scientific men, and with many men high in the State. Hisreal business life commenced after he became Astronomer Royal, andfrom that time forward, during the 46 years that he remained inoffice, he was so entirely wrapped up in the duties of his post thatthe history of the Observatory is the history of his life. For writinghis business life there is abundant material, for he preserved all hiscorrespondence, and the chief sources of information are as follows: (1) His Autobiography. (2) His Annual Reports to the Board of Visitors. (3) His printed Papers entitled "Papers by G. B. Airy. " (4) His miscellaneous private correspondence. (5) His letters to his wife. (6) His business correspondence. (1) His Autobiography, after the time that he became Astronomer Royal, is, as might be expected, mainly a record of the scientific workcarried on at the Greenwich Observatory: but by no means exclusivelyso. About the time when he took charge of the Observatory there was animmense development of astronomical enterprise: observatories werespringing up in all directions, and the Astronomer Royal was expectedto advise upon all of the British and Colonial Observatories. It wasnecessary also for him to keep in touch with the ContinentalObservatories and their work, and this he did very diligently andsuccessfully, both by correspondence and personal intercourse with theforeign astronomers. There was also much work on important subjectsmore or less connected with his official duties--such as geodeticalsurvey work, the establishment of time-balls at different places, longitude determinations, observation of eclipses, and thedetermination of the density of the Earth. Lastly, there was a greatdeal of time and work given to questions not very immediatelyconnected with his office, but on which the Government asked hisassistance in the capacity of general scientific adviser: such werethe Correction of the Compass in iron ships, the Railway GaugeCommission, the Commission for the Restoration of the Standards ofLength and Weight, the Maine Boundary, Lighthouses, the WestminsterClock, the London University, and many other questions. Besides those above-mentioned there were a great many subjects whichhe took up out of sheer interest in the investigations. For it mayfairly be said that every subject of a distinctly practical nature, which could be advanced by mathematical knowledge, had an interest forhim: and his incessant industry enabled him to find time for many ofthem. Amongst such subjects were Tides and Tidal Observations, Clockwork, and the Strains in Beams and Bridges. A certain portion ofhis time was also given to Lectures, generally on current astronomicalquestions, for he held it as his duty to popularize the science as faras lay in his power. And he attended the meetings of the RoyalAstronomical Society with great regularity, and took a very activepart in the discussions and business of the Society. He also did muchwork for the Royal Society, and (up to a certain date) for the BritishAssociation. All of the foregoing matters are recorded pretty fully in hisAutobiography up to the year 1861. After that date the Autobiographyis given in a much more abbreviated form, and might rather be regardedas a collection of notes for his Biography. His private history isgiven very fully for the first part of his life, but is very lightlytouched upon during his residence at Greenwich. A great part of theAutobiography is in a somewhat disjointed state, and appears to havebeen formed by extracts from a number of different sources, such asOfficial Journals, Official Correspondence, and Reports. In editingthe Autobiography it has been thought advisable to omit a large numberof short notes relating to the routine work of the Observatory, totechnical and scientific correspondence, to Papers communicated tovarious Societies and official business connected with them, and tomiscellaneous matters of minor importance. These in the aggregateoccupied a great deal of time and attention. But, from their detachednature, they would have but little general interest. At various placeswill be found short Memoirs and other matter by the Editor. (2) All of his Annual Reports to the Board of Visitors are attached tohis Autobiography and were evidently intended to be read with it andto form part of it. These Reports are so carefully compiled and are socopious that they form a very complete history of the GreenwichObservatory and of the work carried on there during the time that hewas Astronomer Royal. The first Report contained only four pages, butwith the constantly increasing amount and range of work the Reportsconstantly increased in volume till the later Reports contained 21pages. Extracts from these Reports relating to matters of novelty andimportance, and illustrating the principles which guided him in hisconduct of the Observatory, have been incorporated with theAutobiography. (3) The printed "Papers by G. B. Airy" are bound in 14 large quartovolumes. There are 518 of these Papers, on a great variety ofsubjects: a list of them is appended to this history, as also is alist of the books that he wrote, and one or two of the Papers whichwere separately printed. They form a very important part of hislife's work, and are frequently referred to in the presenthistory. They are almost all to be found in the Transactions ofSocieties or in newspapers, and extend over a period of 63 years (1822to 1885). The progress made in certain branches of science during thislong period can very fairly be traced by these Papers. (4) His private correspondence was large, and like his other papers itwas carefully arranged. No business letters of any kind are includedunder this head. In this correspondence letters are occasionally foundeither dealing with matters of importance or in some waycharacteristic, and these have been inserted in this biography. Asalready stated the Autobiography left by Airy is confined almostentirely to science and business, and touches very lightly on privatematters or correspondence. (5) The letters to his wife are very numerous. They were writtenduring his occasional absences from home on business or forrelaxation. On these occasions he rarely let a day pass withoutwriting to his wife, and sometimes he wrote twice on the sameday. They are full of energy and interest and many extracts from themare inserted in this history. A great deal of the personal history istaken from them. (6) All correspondence in any way connected with business during thetime that he was Astronomer Royal is to be found at the RoyalObservatory. It is all bound and arranged in the most perfect order, and any letter throughout this time can be found with the greatestease. It is very bulky, and much of it is, in a historical sense, very interesting. It was no doubt mainly from this correspondence thatthe Autobiography, which so far as related to the Greenwich part of itwas almost entirely a business history, was compiled. The history of the early part of his life was written in great detailand contained a large quantity of family matter which was evidentlynot intended for publication. This part of the Autobiography has beencompressed. The history of the latter part of his life was not writtenby himself at all, and has been compiled from his Journal and othersources. In both these cases, and occasionally in short paragraphsthroughout the narrative, it has been found convenient to write thehistory in the third person. 2, THE CIRCUS, GREENWICH. NOTE. The Syndics of the Cambridge University Press desire to express theirthanks to Messrs Macmillan & Co. For their courteous permission to usein this work the steel engraving of Sir George Biddell Airy publishedin _Nature_ on October 31, 1878. TABLE OF CONTENTS. CHAPTER I. Personal Sketch of George Biddell Airy CHAPTER II. From his birth to his taking his B. A. Degree at Cambridge CHAPTER III. At Trinity College, Cambridge, from his taking his B. A. Degree to histaking charge of the Cambridge Observatory as Plumian Professor CHAPTER IV. At Cambridge Observatory, from his taking charge of the CambridgeObservatory to his residence at Greenwich Observatory as AstronomerRoyal CHAPTER V. At Greenwich Observatory, 1836-1846 CHAPTER VI. At Greenwich Observatory, 1846-1856 CHAPTER VII. At Greenwich Observatory, 1856-1866 CHAPTER VIII. At Greenwich Observatory, 1866-1876 CHAPTER IX. At Greenwich Observatory, from January 1st, 1876, to his resignationof office on August 15th, 1881 CHAPTER X. At the White House, Greenwich, from his resignation of office onAugust 15th, 1881, to his death on January 2nd, 1892 APPENDIX. List of Printed Papers by G. B. Airy, and List of Books written byG. B. Airy INDEX. CHAPTER I. PERSONAL SKETCH OF GEORGE BIDDELL AIRY. The history of Airy's life, and especially the history of his life'swork, is given in the chapters that follow. But it is felt that thepresent Memoir would be incomplete without a reference to thosepersonal characteristics upon which the work of his life hinged andwhich can only be very faintly gathered from his Autobiography. He was of medium stature and not powerfully built: as he advanced inyears he stooped a good deal. His hands were large-boned andwell-formed. His constitution was remarkably sound. At no period inhis life does he seem to have taken the least interest in athleticsports or competitions, but he was a very active pedestrian and couldendure a great deal of fatigue. He was by no means wanting in physicalcourage, and on various occasions, especially in boating expeditions, he ran considerable risks. In debate and controversy he had greatself-reliance, and was absolutely fearless. His eye-sight waspeculiar, and required correction by spectacles the lenses of whichwere ground to peculiar curves according to formulae which he himselfinvestigated: with these spectacles he saw extremely well, and hecommonly carried three pairs, adapted to different distances: he tookgreat interest in the changes that took place in his eye-sight, andwrote several Papers on the subject. In his later years he becamesomewhat deaf, but not to the extent of serious personalinconvenience. The ruling feature of his character was undoubtedly Order. From thetime that he went up to Cambridge to the end of his life his system oforder was strictly maintained. He wrote his autobiography up to datesoon after he had taken his degree, and made his first will as soon ashe had any money to leave. His accounts were perfectly kept by doubleentry throughout his life, and he valued extremely the order ofbook-keeping: this facility of keeping accounts was very useful tohim. He seems not to have destroyed a document of any kind whatever:counterfoils of old cheque-books, notes for tradesmen, circulars, bills, and correspondence of all sorts were carefully preserved in themost complete order from the time that he went to Cambridge; and ahuge mass they formed. To a high appreciation of order he attributedin a great degree his command of mathematics, and sometimes spoke ofmathematics as nothing more than a system of order carried to aconsiderable extent. In everything he was methodical and orderly, andhe had the greatest dread of disorder creeping into the routine workof the Observatory, even in the smallest matters. As an example, hespent a whole afternoon in writing the word "Empty" on large cards, tobe nailed upon a great number of empty packing boxes, because henoticed a little confusion arising from their getting mixed with otherboxes containing different articles; and an assistant could not bespared for this work without withdrawing him from his appointedduties. His arrangement of the Observatory correspondence wasexcellent and elaborate: probably no papers are more easy of referencethan those arranged on his system. His strict habits of order made himinsist very much upon detail in his business with others, and therigid discipline arising out of his system of order made his ruleirksome to such of his subordinates as did not conform readily to it:but the efficiency of the Observatory unquestionably depended mainlyupon it. As his powers failed with age the ruling passion for orderassumed a greater prominence; and in his last days he seemed to bemore anxious to put letters which he received into their proper placefor reference than even to master their contents. His nature was eminently practical, and any subject which had adistinctly practical object, and could be advanced by mathematicalinvestigation, possessed interest for him. And his dislike of meretheoretical problems and investigations was proportionately great. Hewas continually at war with some of the resident Cambridgemathematicians on this subject. Year after year he criticised theSenate House Papers and the Smith's Prize Papers question by questionvery severely: and conducted an interesting and acrimonious privatecorrespondence with Professor Cayley on the same subject. His greatmathematical powers and his command of mathematics are sufficientlyevidenced by the numerous mathematical treatises of the highest orderwhich he published, a list of which is appended to this biography. Buta very important feature of his investigations was the thoroughness ofthem. He was never satisfied with leaving a result as a barrenmathematical expression. He would reduce it, if possible, to apractical and numerical form, at any cost of labour: and would use anyapproximations which would conduce to this result, rather than leavethe result in an unfruitful condition. He never shirked arithmeticalwork: the longest and most laborious reductions had no terrors forhim, and he was remarkably skilful with the various mathematicalexpedients for shortening and facilitating arithmetical work of acomplex character. This power of handling arithmetic was of greatvalue to him in the Observatory reductions and in the Observatory workgenerally. He regarded it as a duty to finish off his work, whateverit was, and the writer well remembers his comment on the mathematicsof one of his old friends, to the effect that "he was too fond ofleaving a result in the form of three complex equations with threeunknown quantities. " To one who had known, in some degree, of theenormous quantity of arithmetical work which he had turned out, andthe unsparing manner in which he had devoted himself to it, there wassomething very pathetic in his discovery, towards the close of hislong life, "that the figures would not add up. " His energy and business capacity were remarkable. He was made for workand could not long be happy without it. Whatever subject he wasengaged upon, he kept his object clearly in view, and made straightfor it, aiming far more at clearness and directness than at eleganceof periods or symmetry of arrangement. He wrote his letters with greatease and rapidity: and having written them he very rarely had occasionto re-write them, though he often added insertions andinterlineations, even in the most important official letters. Withoutthis it would have been impossible for him to have turned out theenormous quantity of correspondence that he did. He never dictatedletters, and only availed himself of clerical assistance in matters ofthe most ordinary routine. In his excursions, as in his work, he wasalways energetic, and could not endure inaction. Whatever there was ofinterest in the places that he visited he examined thoroughly andwithout delay, and then passed on. And he thus accomplished a greatdeal in a short vacation. His letters written to his wife, while hewas on his excursions, are very numerous and characteristic, andafford ample proofs of his incessant energy and activity both of bodyand mind. They are not brilliantly written, for it was not in hisnature to write for effect, and he would never give himself thetrouble to study the composition of his letters, but they arestraight-forward, clear, and concise, and he was never at a loss forsuitable language to express his ideas. He had a wonderful capacityfor enjoyment: the subjects that chiefly interested him were scenery, architecture, and antiquities, but everything novel or curious had aninterest for him. He made several journeys to the Continent, but byfar the greater number of his excursions were made in England andScotland, and there were few parts of the country which he had notvisited. He was very fond of the Lake District of Cumberland, andvisited it very frequently, and each time that he went there the sameset of views had an eternal freshness for him, and he wrote longdescriptions of the scenery and effects with the same raptures as ifhe had seen it for the first time. Many of his letters were writtenfrom Playford, a village in a beautiful part of Suffolk, a few milesfrom Ipswich. Here he had a small property, and generally stayed therefor a short time once or twice a year. He was extremely fond of thiscountry, and was never tired of repeating his walks by the well-knownlanes and footpaths. And, as in Cumberland, the Suffolk country hadan eternal freshness and novelty for him. Wherever he went he wasindefatigable in keeping up his acquaintance with his numerous friendsand his letters abound in social reminiscences. His memory was singularly retentive. It was much remarked at school inhis early days, and in the course of his life he had stored up in hismemory an incredible quantity of poetry, ballads, and miscellaneousfacts and information of all sorts, which was all constantly ready andat his service. It is almost needless to add that his memory wasequally accurate and extensive in matters connected with science orbusiness. His independence of character was no doubt due to and inseparable fromhis great powers. The value of his scientific work greatly dependedupon his self-reliance and independence of thought. And in the heavywork of remodelling the Observatory it was a very valuablequality. This same self-reliance made him in his latter years apt todraw conclusions too confidently and hastily on subjects which he hadtaken up more as a pastime than as work. But whatever he touched hedealt with ably and in the most fearless truthseeking manner, and leftoriginal and vigorous opinions. He had a remarkably well-balanced mind, and a simplicity of naturethat appeared invulnerable. No amount of hero-worship seemed to havethe least effect upon him. And from a very early time he was exposedto a great deal of it. His mind was incessantly engaged oninvestigations of Nature, and this seems to have been with him, as hasbeen the case with others, a preserving influence. This simplicity ofcharacter he retained throughout his life. At the same time he wassensible and shrewd in his money matters and attentive to his personalinterests. And his practical good sense in the general affairs oflife, combined with his calm and steady consideration of pointssubmitted to him, made his advice very valuable. This was especiallyrecognized by his own and his wife's relations, who consulted him onmany occasions and placed the fullest confidence in his absolute senseof justice as well as in his wise counsel. He was extremely liberalin proportion to his means, and gave away money to a large extent toall who had any claim upon him. But he was not in any sense reckless, and kept a most cautious eye on his expenses. He was not indifferentto the honours which he received in the scientific world, but he doesnot appear to have sought them in any way, and he certainly did nottrouble himself about them. His courtesy was unfailing: no amount of trouble could shakeit. Whether it was the Secretary of the Admiralty, or a servant girlwanting her fortune told: whether a begging-letter for money, ormiscellaneous invitations: all had their answer in the most clear andcourteous language. But he would not grant personal interviews when hecould avoid it: they took up too much of his time. His head was soclear that he never seemed to want for the clearest and most directlanguage in expressing his meaning, and his letters are models ofterseness. In all his views and opinions he was strongly liberal. At Cambridge atan early date he was one of the 83 members of the Senate who supportedthe application to permit the granting of medical degrees withoutrequiring an expression of assent to the religious doctrines of theChurch of England. And in 1868 he declined to sign a petition againstthe abolition of religious declarations required of persons admittedto Fellowships or proceeding to the degree of M. A. And he was opposedto every kind of narrowness and exclusiveness. When he was appointedto the post of Astronomer Royal, he stipulated that he should not beasked to vote in any political election. But all his views were in theliberal direction. He was a great reader of theology and churchhistory, and as regarded forms of worship and the interpretation ofthe Scriptures, he treated them with great respect, but from the pointof view of a freethinking layman. In the Preface to his "Notes on theEarlier Hebrew Scriptures" he says, "In regard to the general tone ofthese notes, I will first remark that I have nothing to say on thesubject of verbal inspiration. With those who entertain that doctrine, I can have nothing in common. Nor do I recognize, in the professedlyhistorical accounts, any other inspiration which can exempt them fromthe severest criticism that would be applicable to so-called profaneaccounts, written under the same general circumstances, and in thesame countries. " And his treatment of the subject in the "Notes" shewshow entirely he took a rationalistic view of the whole question. Healso strongly sided with Bishop Colenso in his fearless criticism ofthe Pentateuch, though he dissented from some of his conclusions. Buthe was deeply imbued with the spirit of religion and reflected muchupon it. His whole correspondence conveys the impression of the moststerling integrity and high-mindedness, without a trace ofaffectation. In no letter does there appear a shadow of wavering onmatters of principle, whether in public or private matters, and he wasvery clear and positive in his convictions. The great secret of his long and successful official career was thathe was a good servant and thoroughly understood his position. He neverset himself in opposition to his masters, the Admiralty. He neverhesitated to ask the Admiralty for what he thought right, whether inthe way of money grants for various objects, or for occasionalpermission to give his services to scientific matters not immediatelyconnected with the Observatory. Sometimes the Admiralty refused hisrequests, and he felt this very keenly, but he was far too busy andenergetic to trouble himself about such little slights, and cheerfullyaccepted the situation. What was refused by one Administration wasfrequently granted by another; and in the meantime he was always readyto give his most zealous assistance in any matter that was officiallybrought before him. This cheerful readiness to help, combined with hisgreat ability and punctuality in business matters, made him a veryvaluable servant, and speaking generally he had the confidence of theAdmiralty in a remarkable degree. In many of his Reports to the Boardof Visitors he speaks gratefully of the liberality of the Admiralty inforwarding scientific progress and research. In matters too which areperhaps of minor importance from the high stand-point of science, butwhich are invaluable in the conduct of an important business office, such for example as estimates and official correspondence, he wasorderly and punctual in the highest degree. And, what is by no meansunimportant, he possessed an excellent official style incorrespondence, combined with great clearness of expression. Hisentire honesty of purpose, and the high respect in which he was heldboth at home and abroad, gave great weight to his recommendations. With regard to his habits while he resided at the Observatory, hiscustom was to work in his official room from 9 to about 2. 30, thoughin summer he was frequently at work before breakfast. He then took abrisk walk, and dined at about 3. 30. This early hour had beenprescribed and insisted upon by his physician, Dr Haviland ofCambridge, in whom he had great confidence. He ate heartily, thoughsimply and moderately, and slept for about an hour after dinner. Hethen had tea, and from about 7 to 10 he worked in the same room withhis family. He would never retire to a private room, and regarded thesociety of his family as highly beneficial in "taking the edge off hiswork. " His powers of abstraction were remarkable: nothing seemed todisturb him; neither music, singing, nor miscellaneous conversation. He would then play a game or two at cards, read a few pages of aclassical or historical book, and retire at 11. On Sundays he attendedmorning service at church, and in the evening read a few prayers verycarefully and impressively to his whole household. He was veryhospitable, and delighted to receive his friends in a simple andnatural way at his house. In this he was most admirably aided by hiswife, whose grace and skill made everything pleasant to theirguests. But he avoided dinner-parties as much as possible--theyinterfered too much with his work--and with the exception ofscientific and official dinners he seldom dined away from home. Histastes were entirely domestic, and he was very happy in hisfamily. With his natural love of work, and with the incessant callsupon him, he would soon have broken down, had it not been for hissystem of regular relaxation. Two or three times a year he took aholiday: generally a short run of a week or ten days in the spring, atrip of a month or thereabouts in the early autumn, and about threeweeks at Playford in the winter. These trips were always conducted inthe most active manner, either in constant motion from place to place, or in daily active excursions. This system he maintained with greatregularity, and from the exceeding interest and enjoyment that he tookin these trips his mind was so much refreshed and steadied that healways kept himself equal to his work. Airy seems to have had a strong bent in the direction of astronomyfrom his youth, and it is curious to note how well furnished he was, by the time that he became Astronomer Royal, both with astronomy inall its branches, and with the kindred sciences so necessary for thepractical working and improvement of it. At the time that he went toCambridge Physical Astronomy was greatly studied there and formed amost important part of the University course. He eagerly availedhimself of this, and mastered the Physical Astronomy in the mostthorough manner, as was evidenced by his Papers collected in his"Mathematical Tracts, " his investigation of the Long Inequality of theEarth and Venus, and many other works. As Plumian Professor he hadcharge of the small Observatory at Cambridge, where he did a greatdeal of the observing and reduction work himself, and becamethoroughly versed in the practical working of an Observatory. Theresult of this was immediately seen in the improved methods which heintroduced at Greenwich, and which were speedily imitated at otherObservatories. Optics and the Undulatory Theory of Light had been veryfavourite subjects with him, and he had written and lecturedfrequently upon them. In the construction of the new and powerfultelescopes and other optical instruments required from time to timethis knowledge was very essential, for in its instrumental equipmentthe Greenwich Observatory was entirely remodelled during his tenure ofoffice. And in many of the matters referred to him, as for instancethat of the Lighthouses, a thorough knowledge of Optics was mostvaluable. He had made a great study of the theory and construction ofclocks, and this knowledge was invaluable to him at Greenwich in theestablishment of new and more accurate astronomical clocks, andespecially in the improvement of chronometers. He had carefullystudied the theory of pendulums, and had learned how to use them inhis experiments in the Cornish mines. This knowledge he afterwardsutilized very effectively at the Harton Pit in comparing the densityof the Earth's crust with its mean density; and it was very useful tohim in connection with geodetic surveys and experiments on which hewas consulted. And his mechanical knowledge was useful in almosteverything. The subjects (outside those required for his professional work) inwhich he took most interest were Poetry, History, Theology, Antiquities, Architecture, and Engineering. He was well acquaintedwith standard English poetry, and had committed large quantities tomemory, which he frequently referred to as a most valuable acquisitionand an ever-present relief and comfort to his mind. History andtheology he had studied as opportunity offered, and without beingwidely read in them he was much at home with them, and his powerfulmemory made the most of what he did read. Antiquities and architecturewere very favourite subjects with him. He had visited most of thecamps and castles in the United Kingdom and was never tired of tracingtheir connection with ancient military events: and he wrote severalpapers on this subject, especially those relating to the Romaninvasions of Britain. Ecclesiastical architecture he was very fond of:he had visited nearly all the cathedrals and principal churches inEngland, and many on the Continent, and was most enthusiastic on theirdifferent styles and merits: his letters abound in critical remarks onthem. He was extremely well versed in mechanics, and in the principlesand theory of construction, and took the greatest interest in largeengineering works. This led to much communication with Stephenson, Brunel, and other engineers, who consulted him freely on the subjectof great works on which they were engaged: in particular he renderedmuch assistance in connection with the construction of the BritanniaBridge over the Menai Straits. There were various other subjects whichhe read with much interest (Geology in particular), but he made nostudy of Natural History, and knew very little about it beyonddetached facts. His industry was untiring, and in going over his booksone by one it was very noticeable how large a number of them werefeathered with his paper "marks, " shewing how carefully he had readthem and referred to them. His nature was essentially cheerful, andliterature of a witty and humourous character had a great charm forhim. He was very fond of music and knew a great number of songs; andhe was well acquainted with the theory of music: but he was noperformer. He did not sketch freehand but made excellent drawings withhis Camera Lucida. At the time when he took his degree (1823) and for many yearsafterwards there was very great activity of scientific investigationand astronomical enterprise in England. And, as in the times ofFlamsteed and Halley, the earnest zeal of men of science occasionallyled to much controversy and bitterness amongst them. Airy was by nomeans exempt from such controversies. He was a man of keensensitiveness, though it was combined with great steadiness of temper, and he never hesitated to attack theories and methods that heconsidered to be scientifically wrong. This led to differences withIvory, Challis, South, Cayley, Archibald Smith, and others; buthowever much he might differ from them he was always personallycourteous, and the disputes generally went no farther than as regardedthe special matter in question. Almost all these controversialdiscussions were carried on openly, and were published in theAthenaeum, the Philosophical Magazine, or elsewhere; for he printednearly everything that he wrote, and was very careful in the selectionof the most suitable channels for publication. He regarded it as aduty to popularize as much as possible the work done at theObservatory, and to take the public into his confidence. And this heeffected by articles communicated to newspapers, lectures, numerousPapers written for scientific societies, reports, debates, andcritiques. His strong constitution and his regular habits, both of work andexercise, are sufficient explanation of the good health which ingeneral he enjoyed. Not but what he had sharp touches of illness fromtime to time. At one period he suffered a good deal from an attack ofeczema, and at another from a varicose vein in his leg, and he wasoccasionally troubled with severe colds. But he bore these ailmentswith great patience and threw them off in course of time. He was happyin his marriage and in his family, and such troubles and distresses aswere inevitable he accepted calmly and quietly. In his death, as inhis life, he was fortunate: he had no long or painful illness, and hewas spared the calamity of aberration of intellect, the saddest of allvisitations. CHAPTER II. FROM HIS BIRTH TO HIS TAKING HIS B. A. DEGREE AT CAMBRIDGE. FROM JULY 27TH 1801 TO JANUARY 18TH 1823. George Biddell Airy was born at Alnwick in Northumberland on July 27th1801. His father was William Airy of Luddington in Lincolnshire, thedescendant of a long line of Airys who have been traced back with avery high degree of probability to a family of that name which wassettled at Kentmere in Westmorland in the 14th century. A branch ofthis family migrated to Pontefract in Yorkshire, where they seem tohave prospered for many years, but they were involved in theconsequences of the Civil Wars, and one member of the family retiredto Ousefleet in Yorkshire. His grandson removed to Luddington inLincolnshire, where his descendants for several generations pursuedthe calling of small farmers. George Biddell Airy's mother, Ann Airy, was the daughter of George Biddell, a well-to-do farmer in Suffolk. William Airy, the father of George Biddell Airy, was a man of greatactivity and strength, and of prudent and steady character. When ayoung man he became foreman on a farm in the neighbourhood ofLuddington, and laid by his earnings in summer in order to educatehimself in winter. For a person in his rank, his education wasunusually good, in matters of science and in English literature. Butat the age of 24 he grew tired of country labour, and obtained a postin the Excise. After serving in various Collections he was appointedCollector of the Northumberland Collection on the 15th August 1800, and during his service there his eldest son George Biddell Airy wasborn. The time over which his service as Officer and Supervisorextended was that in which smuggling rose to a very high pitch, and inwhich the position of Excise Officer was sometimes dangerous. He wasremarkable for his activity and boldness in contests with smugglers, and made many seizures. Ann Airy, the mother of George Biddell Airy, was a woman of great natural abilities both speculative and practical, kind as a neighbour and as head of a family, and was deeply loved andrespected. The family consisted of George Biddell, Elizabeth, William, and Arthur who died young. William Airy was appointed to Hereford Collection on 22nd October1802, and removed thither shortly after. He stayed at Hereford till hewas appointed to Essex Collection on 28th February 1810, and duringthis time George Biddell was educated at elementary schools inwriting, arithmetic, and a little Latin. He records of himself that hewas not a favourite with the schoolboys, for he had very little animalvivacity and seldom joined in active play with his schoolfellows. Butin the proceedings of the school he was successful, and was afavourite with his master. On the appointment of William Airy to Essex Collection, the familyremoved to Colchester on April 5th 1810. Here George Biddell was firstsent to a large school in Sir Isaac's Walk, then kept by Mr ByattWalker, and was soon noted for his correctness in orthography, geography, and arithmetic. He evidently made rapid progress, for onone occasion Mr Walker said openly in the schoolroom how remarkable itwas that a boy 10 years old should be the first in the school. At thisschool he stayed till the end of 1813 and thoroughly learnedarithmetic (from Walkingame's book), book-keeping by double entry (onwhich knowledge throughout his life he set a special value), the useof the sliding rule (which knowledge also was specially useful to himin after life), mensuration and algebra (from Bonnycastle's books). Healso studied grammar in all its branches, and geography, and acquiredsome knowledge of English literature, beginning with that admirablebook The Speaker, but it does not appear that Latin and Greek wereattended to at this school. He records that at this time he learned aninfinity of snatches of songs, small romances, &c. , which his powerfulmemory retained most accurately throughout his life. He was no hand atactive play: but was notorious for his skill in constructing guns forshooting peas and arrows, and other mechanical contrivances. At homehe relates that he picked up a wonderful quantity of learning from hisfather's books. He read and remembered much poetry from such standardauthors as Milton, Pope, Gay, Gray, Swift, &c. , which was destined toprove in after life an invaluable relaxation for his mind. But he alsostudied deeply an excellent Cyclopaedia called a Dictionary of Artsand Sciences in three volumes folio, and learned from it much aboutship-building, navigation, fortification, and many other subjects. During this period his valuable friendship with his uncle ArthurBiddell commenced. Arthur Biddell was a prosperous farmer and valuerat Playford near Ipswich. He was a well-informed and able man, ofpowerful and original mind, extremely kind and good-natured, andgreatly respected throughout the county. In the Autobiography ofGeorge Biddell Airy he states as follows: "I do not remember precisely when it was that I first visited my uncleArthur Biddell. I think it was in a winter: certainly as early as thewinter of 1812--13. Here I found a friend whose society I could enjoy, and I entirely appreciated and enjoyed the practical, mechanical, andat the same time speculative and enquiring talents of ArthurBiddell. He had a library which, for a person in middle life, may becalled excellent, and his historical and antiquarian knowledge was notsmall. After spending one winter holiday with him, it easily came topass that I spent the next summer holiday with him: and at the nextwinter holiday, finding that there was no precise arrangement for mymovements, I secretly wrote him a letter begging him to come with agig to fetch me home with him: he complied with my request, giving nohint to my father or mother of my letter: and from that time, one-third of every year was regularly spent with him till I went toCollege. How great was the influence of this on my character andeducation I cannot tell. It was with him that I became acquainted withthe Messrs Ransome, W. Cubitt the civil engineer (afterwards SirW. Cubitt), Bernard Barton, Thomas Clarkson (the slave-tradeabolitionist), and other persons whose acquaintance I have valuedhighly. It was also with him that I became acquainted with the worksof the best modern poets, Scott, Byron, Campbell, Hogg, and others: asalso with the Waverley Novels and other works of merit. " In 1813 William Airy lost his appointment of Collector of Excise andwas in consequence very much straitened in his circumstances. Butthere was no relaxation in the education of his children, and at thebeginning of 1814 George Biddell was sent to the endowed GrammarSchool at Colchester, then kept by the Rev. E. Crosse, and remainedthere till the summer of 1819, when he went to College. TheAutobiography proceeds as follows: "I became here a respectable scholar in Latin and Greek, to the extentof accurate translation, and composition of prose Latin: in regard toLatin verses I was I think more defective than most scholars who takethe same pains, but I am not much ashamed of this, for I entirelydespise the system of instruction in verse composition. "My father on some occasion had to go to London and brought back forme a pair of 12-inch globes. They were invaluable to me. The firststars which I learnt from the celestial globe were alpha Lyrae, alphaAquilae, alpha Cygni: and to this time I involuntarily regard thesestars as the birth-stars of my astronomical knowledge. Havingsomewhere seen a description of a Gunter's quadrant, I perceived thatI could construct one by means of the globe: my father procured for mea board of the proper shape with paper pasted on it, and on this Itraced the lines of the quadrant. "My command of geometry was tolerably complete, and one way in which Ifrequently amused myself was by making paper models (most carefullydrawn in outline) which were buttoned together without any cement orsewing. Thus I made models, not only of regular solids, regularlyirregular solids, cones cut in all directions so as to shew the conicsections, and the like, but also of six-gun batteries, intrenchmentsand fortresses of various kinds &c. "From various books I had learnt the construction of the steam-engine:the older forms from the Dictionary of Arts and Sciences; newer formsfrom modern books. The newest form however (with the sliding steamvalve) I learnt from a 6-horse engine at Bawtrey's brewery (in whichMr Keeling the father of my schoolfellow had acquired apartnership). I frequently went to look at this engine, and on oneoccasion had the extreme felicity of examining some of its parts whenit was opened for repair. "In the mean time my education was advancing at Playford. The firstrecord, I believe, which I have of my attention to mechanics there isthe plan of a threshing-machine which I drew. But I was acquiringvaluable information of all kinds from the Encyclopaedia Londinensis, a work which without being high in any respect is one of the mostgenerally useful that I have seen. But I well remember one of the mostimportant steps that I ever made. I had tried experiments with theobject-glass of an opera-glass and was greatly astonished at theappearance of the images of objects seen through the glass underdifferent conditions. By these things my thoughts were turned toaccurate optics, and I read with care Rutherford's Lectures, which myuncle possessed. The acquisition of an accurate knowledge of theeffect of optical constructions was one of the most charmingattainments that I ever reached. Long before I went to College Iunderstood the action of the lenses of a telescope better than mostopticians. I also read with great zeal Nicholson's Dictionary ofChemistry, and occasionally made chemical experiments of aninexpensive kind: indeed I grew so fond of this subject that there wassome thought of apprenticing me to a chemist. I also attended tosurveying and made a tolerable survey and map of my uncle's farm. "At school I was going on successfully, and distinguished myselfparticularly by my memory. It was the custom for each boy once a weekto repeat a number of lines of Latin or Greek poetry, the numberdepending very much on his own choice. I determined on repeating 100every week, and I never once fell below that number and was sometimesmuch above it. It was no distress to me, and great enjoyment. AtMichaelmas 1816 I repeated 2394 lines, probably without missing aword. I do not think that I was a favourite with Mr Crosse, but hecertainly had a high opinion of my powers and expressed this to myfather. My father entertained the idea of sending me to College, whichMr Crosse recommended: but he heard from some college man that theexpense would be _£200_ a year, and he laid aside all thoughts of it. "The farm of Playford Hall was in 1813 or 1814 hired by ThomasClarkson, the slave-trade abolitionist. My uncle transacted muchbusiness for him (as a neighbour and friend) in the management of thefarm &c. For a time, and they became very intimate. My uncle beggedhim to examine me in Classical knowledge, and he did so, I think, twice. He also gave some better information about the probableexpenses &c. At College. The result was a strong recommendation by myuncle or through my uncle that I should be sent to Cambridge, and thiswas adopted by my father. I think it likely that this was in 1816. "In December 1816, Dealtry's Fluxions was bought for me, and I read itand understood it well. I borrowed Hutton's Course of Mathematics ofold Mr Ransome, who had come to reside at Greenstead near Colchester, and read a good deal of it. "About Ladyday 1817 I began to read mathematics with Mr Rogers(formerly, I think, a Fellow of Sidney College, and an indifferentmathematician of the Cambridge school), who had succeeded a Mr Tweedas assistant to Mr Crosse in the school. I went to his house twice aweek, on holiday afternoons. I do not remember how long I receivedlessons from him, but I think to June, 1818. This course was extremelyvaluable to me, not on account of Mr Rogers's abilities (for Iunderstood many things better than he did) but for its training meboth in Cambridge subjects and in the Cambridge accurate methods oftreating them. I went through Euclid (as far as usually read), Wood'sAlgebra, Wood's Mechanics, Vince's Hydrostatics, Wood's Optics, Trigonometry (in a geometrical treatise and also in Woodhouse'salgebraical form), Fluxions to a good extent, Newton's Principia tothe end of the 9th section. This was a large quantity, but I read itaccurately and understood it perfectly, and could write out any one ofthe propositions which I had read in the most exact form. My connexionwith Mr Rogers was terminated by _his_ giving me notice that he couldnot undertake to receive me any longer: in fact I was too much forhim. I generally read these books in a garret in our house in GeorgeLane, which was indefinitely appropriated to my brother and myself. Ifind that I copied out Vince's Conic Sections in February, 1819. Thefirst book that I copied was the small geometrical treatise onTrigonometry, in May, 1817: to this I was urged by old Mr Ransome, upon my complaining that I could not purchase the book: and it was nobad lesson of independence to me. " During the same period 1817-1819 he was occupied at school ontranslations into blank verse from the Aeneid and Iliad, and readthrough the whole of Sophocles very carefully. The classical knowledge which he thus gained at school andsubsequently at Cambridge was sound, and he took great pleasure in it:throughout his life he made a practice of keeping one or other of theClassical Authors at hand for occasional relaxation. He terminated hisschooling in June 1819. Shortly afterwards his father left Colchesterand went to reside at Bury St Edmund's. The Autobiography proceeds asfollows: "Mr Clarkson was at one time inclined to recommend me to go to StPeter's College (which had been much enriched by a bequest from a MrGisborne). But on giving some account of me to his friend Mr JamesD. Hustler, tutor of Trinity College, Mr Hustler urged upon him that Iwas exactly the proper sort of person to go to Trinity College. Andthus it was settled (mainly by Mr Clarkson) that I should be enteredat Trinity College. I think that I was sent for purposely fromColchester to Playford, and on March 6th, 1819, I rode in company withMr Clarkson from Playford to Sproughton near Ipswich to be examined bythe Rev. Mr Rogers, incumbent of Sproughton, an old M. A. Of TrinityCollege; and was examined, and my certificate duly sent to Mr Hustler;and I was entered on Mr Hustler's side as Sizar of Trinity College. "In the summer of 1819 I spent some time at Playford. On July 27th, 1819 (my birthday, 18 years old), Mr Clarkson invited me to dinner, tomeet Mr Charles Musgrave, Fellow of Trinity College, who was residingfor a short time at Grundisburgh, taking the church duty there for DrRamsden, the Rector. It was arranged that I should go to Grundisburghthe next day (I think) to be examined in mathematics by Mr Musgrave. Iwent accordingly, and Mr Musgrave set before me a paper of questionsin geometry, algebra, mechanics, optics, &c. Ending with the firstproposition of the Principia. I knew nothing more about my answers atthe time; but I found long after that they excited so much admirationthat they were transmitted to Cambridge (I forget whether to MrMusgrave's brother, a Fellow of Trinity College and afterwardsArchbishop of York, or to Mr Peacock, afterwards Dean of Ely) and werelong preserved. "The list of the Classical subjects for the first year in TrinityCollege was transmitted to me, as usual, by Mr Hustler. They were--TheHippolytus of Euripides, the 3rd Book of Thucydides, and the 2ndPhilippic of Cicero. These I read carefully and noted before goingup. Mr Hustler's family lived in Bury; and I called on him and saw himin October, introduced by Mr Clarkson. On the morning of October 18th, 1819, I went on the top of the coach to Cambridge, knowing nobodythere but Mr Hustler, but having letters of introduction from MrCharles Musgrave to Professor Sedgwick, Mr Thomas Musgrave, and MrGeorge Peacock, all Fellows of Trinity College. "I was set down at the Hoop, saw Trinity College for the first time, found Mr Hustler, was conducted by his servant to the robe-maker's, where I was invested in the cap and blue gown, and after some furtherwaiting was installed into lodgings in Bridge Street. At 4 o'clock Iwent to the College Hall and was introduced by Mr Hustler to severalundergraduates, generally clever men, and in the evening I attendedChapel in my surplice (it being St Luke's day) and witnessed thatsplendid service of which the occasional exhibition well befits theplace. "As soon as possible, I called on Mr Peacock, Mr Musgrave, andProfessor Sedgwick. By all I was received with great kindness: myexamination papers had been sent to them, and a considerablereputation preceded me. Mr Peacock at once desired that I would notconsider Mr C. Musgrave's letter as an ordinary introduction, but thatI would refer to him on all occasions. And I did so for several years, and always received from him the greatest assistance that he couldgive. I think that I did not become acquainted with Mr Whewell tillthe next term, when I met him at a breakfast party at Mr Peacock's. MrPeacock at once warned me to arrange for taking regular exercise, andprescribed a walk of two hours every day before dinner: a rule towhich I attended regularly, and to which I ascribe the continuance ofgood general health. "I shewed Mr Peacock a manuscript book which contained a number oforiginal Propositions which I had investigated. These much increasedmy reputation (I really had sense enough to set no particular value onit) and I was soon known by sight to almost everybody in theUniversity. A ridiculous little circumstance aided in this. The formerrule of the University (strictly enforced) had been that all studentsshould wear drab knee-breeches: and I, at Mr Clarkson'srecommendation, was so fitted up. The struggle between the old dressand the trowsers customary in society was still going on but almostterminated, and I was one of the very few freshmen who retained theold habiliments. This made me in some measure distinguishable:however at the end of my first three terms I laid these aside. "The College Lectures began on Oct. 22: Mr Evans at 9 on theHippolytus, and Mr Peacock at 10 on Euclid (these being the AssistantTutors on Mr Hustler's side): and then I felt myself established. "I wrote in a day or two to my uncle Arthur Biddell, and I receivedfrom him a letter of the utmost kindness. He entered gravely on theconsideration of my prospects, my wants, &c. : and offered at all timesto furnish me with money, which he thought my father's parsimonioushabits might make him unwilling to do. I never had occasion to availmyself of this offer: but it was made in a way which in no smalldegree strengthened the kindly feelings that had long existed betweenus. "I carefully attended the lectures, taking notes as appearednecessary. In Mathematics there were geometrical problems, algebra, trigonometry (which latter subjects the lectures did not reach tillthe terms of 1820). Mr Peacock gave me a copy of Lacroix'sDifferential Calculus as translated by himself and Herschel andBabbage, and also a copy of their Examples. At this time, the use ofDifferential Calculus was just prevailing over that of Fluxions (whichI had learnt). I betook myself to it with great industry. I also mademyself master of the theories of rectangular coordinates and some ofthe differential processes applying to them, which only a few of thebest of the university mathematicians then wholly possessed. InClassical subjects I read the Latin (Seneca's) and English Hippolytus, Racine's Phèdre (which my sister translated for me), and all otherbooks to which I was referred, Aristotle, Longinus, Horace, Bentley, Dawes &c. , made verse translations of the Greek Hippolytus, and wasconstantly on the watch to read what might be advantageous. "Early in December Mr Hustler sent for me to say that one of theCompany of Fishmongers, Mr R. Sharp, had given to Mr John H. Smyth, M. P. For Norwich, the presentation to a small exhibition of _£20_ ayear, which Mr Smyth had placed in Mr Hustler's hands, and which MrHustler immediately conferred on me. This was my first step towardspecuniary independence. I retained this exhibition till I became aFellow of the College. "I stayed at Cambridge during part of the winter vacation, and toavoid expense I quitted my lodgings and went for a time intosomebody's rooms in the Bishop's Hostel. (It is customary for thetutors to place students in rooms when their right owners are absent. )I took with me Thucydides and all relating to it, and read the book, upon which the next term's lectures were to be founded, verycarefully. The latter part of the vacation I spent at Bury, where Ibegan with the assistance of my sister to pick up a little French: asI perceived that it was absolutely necessary for enabling me to readmodern mathematics. "During a part of the time I employed myself in writing out a paper onthe geometrical interpretation of the algebraical expressionsqrt(-1). I think that the original suggestion of perpendicular linecame from some book (I do not remember clearly), and I worked it outin several instances pretty well, especially in De Moivre's Theorem. Ihad spoken of it in the preceding term to Mr Peacock and he encouragedme to work it out. The date at the end is 1820, January 21. When sometime afterwards I spoke of it to Mr Hustler, he disapproved of myemploying my time on such speculations. About the last day of JanuaryI returned to Cambridge, taking up my abode in my former lodgings. Ishewed my paper on sqrt(-1) to Mr Peacock, who was much pleased withit and shewed it to Mr Whewell and others. "On February 1 I commenced two excellent customs. The first was thatI always had upon my table a quire of large-sized scribbling-papersewn together: and upon this paper everything was entered:translations into Latin and out of Greek, mathematical problems, memoranda of every kind (the latter transferred when necessary to thesubsequent pages), and generally with the date of the day. This is amost valuable custom. The other was this: as I perceived that to writeLatin prose well would be useful to me, I wrote a translation ofEnglish into Latin every day. However much pressed I might be withother business, I endeavoured to write at least three or four words, but if possible I wrote a good many sentences. "I may fix upon this as the time when my daily habits were settled inthe form in which they continued for several years. I rose in time forthe chapel service at 7. It was the College regulation that everystudent should attend Chapel four mornings and four evenings (Sundaybeing one of each) in every week: and in this I never failed. Afterchapel service I came to my lodgings and breakfasted. At 9 I went toCollege lectures, which lasted to 11. Most of my contemporaries, beingintended for the Church, attended also divinity lectures: but I neverdid. I then returned, put my lecture notes in order, wrote my piece ofLatin prose, and then employed myself on the subject which I wasreading for the time: usually taking mathematics at this hour. At 2 ora little sooner I went out for a long walk, usually 4 or 5 miles intothe country: sometimes if I found companions I rowed on the Cam (apractice acquired rather later). A little before 4 I returned, and at4 went to College Hall. After dinner I lounged till evening chapeltime, 1/2 past 5, and returning about 6 I then had tea. Then I readquietly, usually a classical subject, till 11; and I never, even inthe times when I might seem most severely pressed, sat up later. "From this time to the close of the annual examination (beginning ofJune) I remained at Cambridge, stopping there through the EasterVacation. The subjects of the mathematical lectures were ordinaryalgebra and trigonometry: but Mr Peacock always had some privateproblems of a higher class for me, and saw me I believe every day. Thesubjects of the Classical lectures were, the termination ofHippolytus, the book of Thucydides and the oration of Cicero. Inmathematics I read Whewell's Mechanics, then just published (the firstinnovation made in the Cambridge system of Physical Sciences for manyyears): and I find in my scribbling-paper notes, integrals, centralforces, Finite Differences, steam-engine constructions and powers, plans of bridges, spherical trigonometry, optical calculationsrelating to the achromatism of eye-pieces and achromaticobject-glasses with lenses separated, mechanical problems, Transit ofVenus, various problems in geometrical astronomy (I think it was atthis time that Mr Peacock had given me a copy of Woodhouse's Astronomy1st Edition), the rainbow, plans for anemometer and for a wind-pumpingmachine, clearing lunars, &c. , with a great number of geometricalproblems. I remark that my ideas on the Differential Calculus had notacquired on some important points the severe accuracy which theyacquired in a few months. In Classics I read the Persae of Aeschylus, Greek and Roman history very much (Mitford, Hooke, Ferguson) and thebooks of Thucydides introductory to that of the lecture subject (the3rd): and attended to Chronology. On the scribbling-paper areverse-translations from Euripides, careful prose-translations fromThucydides, maps, notes on points of grammar &c. I have also littleMS. Books with abundant notes on all these subjects: I usually made alittle book when I pursued any subject in a regular way. "On May 1st Mr Dobree, the head lecturer, sent for me to say that heappointed me head-lecturer's Sizar for the next year. The stipend ofthis office was _£10_, a sum upon which I set considerable value in myanxiety for pecuniary independence: but it was also gratifying to meas shewing the way in which I was regarded by the College authorities. "On Wednesday, May 24th, 1820, the examination began. I was anxiousabout the result of the examination, but only in such a degree as tomake my conduct perfectly steady and calm, and to prevent me fromattempting any extraordinary exertion. "When the Classes were published the first Class of the Freshman'sYear (alphabetically arranged, as is the custom) stood thus: Airy, Boileau, Childers, Drinkwater, Field, Iliff, Malkin, Myers, Romilly, Strutt, Tate, Winning. It was soon known however that I was first ofthe Class. It was generally expected (and certainly by me) that, considering how great a preponderance the Classics were understood, inthe known system of the College, to have in determining the order ofmerit, Field would be first. However the number of marks which Fieldobtained was about 1700, and that which I obtained about 1900. Noother competitor, I believe, was near us. "--In a letter to Airy fromhis College Tutor, Mr J. D. Hustler, there is the following passage:"It is a matter of extreme satisfaction to me that in the lateexamination you stood not only in the First Class but first of thefirst. I trust that your future exertions and success will becommensurate with this honourable beginning. " "Of the men whom I have named, Drinkwater (Bethune) was afterwardsLegal Member of the Supreme Court of India, Field was afterwardsRector of Reepham, Romilly (afterwards Lord Romilly) becameSolicitor-General, Strutt (afterwards Lord Belper) became M. P. ForDerby and First Commissioner of Railways, Tate was afterwards masterof Richmond Endowed School, Childers was the father of Childers whowas subsequently First Lord of the Admiralty. "I returned to Bury immediately. While there, some students (some ofthem men about to take their B. A. Degree at the next January) appliedto me to take them as pupils, but I declined. This year of my lifeenabled me to understand how I stood among men. I returned toCambridge about July 11th. As a general rule, undergraduates are notallowed to reside in the University during the Long Vacation. Ibelieve that before I left, after the examination, I had made out thatI should be permitted to reside: or I wrote to Mr Hustler. I appliedto Mr Hustler to be lodged in rooms in College: and was put, firstinto rooms in Bishop's Hostel, and subsequently into rooms in theGreat Court. "The first affair that I had in College was one of disappointment byno means deserving the importance which it assumed in my thoughts. Ihad been entered a Sizar, but as the list of Foundation Sizars wasfull, my dinners in Hall were paid for. Some vacancies had arisen: andas these were to be filled up in order of merit, I expected one: andin my desire for pecuniary independence I wished for it veryearnestly. However, as in theory all of the first class were equal, and as there were some Sizars in it senior in entrance to me, theyobtained places first: and I was not actually appointed till after thenext scholarship examination (Easter 1821). However a specialarrangement was made, allowing me (I forget whether others) to sit atthe Foundation-Sizars' table whenever any of the number was absent:and in consequence I received practically nearly the full benefits. "Mr Peacock, who was going out for the vacation, allowed me access tohis books. I had also (by the assistance of various Fellows, who alltreated me with great kindness, almost to a degree of respect) commandof the University Library and Trinity Library: and spent this LongVacation, like several others, very happily indeed. "The only non-mathematical subjects of the next examination were TheGospel of St Luke, Paley's Evidences, and Paley's Moral and PoliticalPhilosophy. Thus my time was left more free to mathematics and togeneral classics than last year. I now began a custom which Imaintained for some years. Generally I read mathematics in themorning, and classics for lectures in the afternoon: but invariably Ibegan at 10 o'clock in the evening to read with the utmost severitysome standard classics (unconnected with the lectures) and at 11precisely I left off and went to bed. I continued my dailytranslations into Latin prose as before. "On August 24th, 1820, Rosser, a man of my own year, engaged me asprivate tutor, paying at the usual rate (_£14_ for a part of theVacation, and _£14_ for a term): and immediately afterwards his friendBedingfield did the same. This occupied two hours every day, and Ifelt that I was now completely earning my own living. I never receiveda penny from my friends after this time. "I find on my scribbling-paper various words which shew that inreading Poisson I was struggling with French words. There are alsoFinite Differences and their Calculus, Figure of the Earth (force tothe center), various Attractions (some evidently referring toMaclaurin's), Integrals, Conic Sections, Kepler's Problem, AnalyticalGeometry, D'Alembert's Theorem, Spherical Aberration, Rotations roundthree axes (apparently I had been reading Euler), Floating bodies, Evolute of Ellipse, Newton's treatment of the Moon's Variation. Iattempted to extract something from Vince's Astronomy on the physicalexplanation of Precession: but in despair of understanding it, andhaving made out an explanation for myself by the motion round threeaxes, I put together a little treatise (Sept. 10, 1820) which withsome corrections and additions was afterwards printed in myMathematical Tracts. On Sept. 14th I bought Woodhouse's PhysicalAstronomy, and this was quite an epoch in my mathematicalknowledge. First, I was compelled by the process of "changing theindependent variable" to examine severely the logic of theDifferential Calculus. Secondly, I was now able to enter on the Theoryof Perturbations, which for several years had been the desired land tome. "At the Fellowship Election of Oct. 1st, Sydney Walker (among otherpersons) was elected Fellow. He then quitted the rooms in which he hadlived (almost the worst in the College), and I immediately tookthem. They suited me well and I lived very happily in them till I waselected Scholar. They are small rooms above the middle staircase onthe south side of Neville's Court. (Mr Peacock's rooms were on thesame staircase. ) I had access to the leads on the roof of the buildingfrom one of my windows. This was before the New Court was built: mybest window looked upon the garden of the College butler. "I had brought to Cambridge the telescope which I had made atColchester, and about this time I had a stand made by a carpenter atCambridge: and I find repeated observations of Jupiter and Saturn madein this October term. "Other mathematical subjects on my scribbling-paper are: GeometricalAstronomy, Barometers (for elevations), Maclaurin's Figure of theEarth, Lagrange's Theorem, Integrals, Differential Equations of thesecond order, Particular Solutions. In general mathematics I had muchdiscussion with Atkinson (who was Senior Wrangler, January 1821), andin Physics with Rosser, who was a friend of Sir Richard Phillips, avain objector to gravitation. In Classics I read Aeschylus andHerodotus. "On October 5th I received notice from the Head Lecturer to declaim inEnglish with Winning. (This exercise consists in preparing acontroversial essay, learning it by heart, and speaking it in Chapelafter the Thursday evening's service. ) On October 6th we agreed onthe subject, "Is natural difference to be ascribed to moral or tophysical causes?" I taking the latter side. I spoke the declamation(reciting it without missing a word) on October 25th. On October 26thI received notice of Latin declamation with Myers: subject agreed on, "Utrum civitati plus utilitatis an incommodi afferant leges quae advitas privatorum hominum ordinandas pertinent"; I took the former. Thedeclamation was recited on November 11, when a curious circumstanceoccurred. My declamation was rather long: it was the first Saturday ofthe term on which a declamation had been spoken: and it was the day onwhich arrived the news of the withdrawal of the Bill of Pains andPenalties against Queen Caroline. (This trial had been going onthrough the summer, but I knew little about it. ) In consequence theimpatience of the undergraduates was very great, and there was such anuproar of coughing &c. In the Chapel as probably was never known. TheMaster (Dr Wordsworth, appointed in the beginning of the summer on thedeath of Dr Mansell, and to whom I had been indirectly introduced byMrs Clarkson) and Tutors and Deans tried in vain to stop thehubbub. However I went on steadily to the end, not at allfrightened. On the Monday the Master sent for me to make a sort ofapology in the name of the authorities, and letters to the Tutors wereread at the Lectures, and on the whole the transaction was nowisedisagreeable to me. "On the Commemoration Day, December 15th, I received my Prize(Mitford's Greece) as First-Class man, after dinner in the CollegeHall. After a short vacation spent at Bury and Playford I returned toCambridge, walking from Bury on Jan. 22nd, 1821. During the next termI find in Mathematics Partial Differential Equations, Tides, Sound, Calculus of Variations, Composition of rotary motions, Motion inresisting medium, Lhuillier's theorem, Brightness of an object as seenthrough a medium with any possible law of refraction (a goodinvestigation), star-reductions, numerical calculations connected withthem, equilibrium of chain under centripetal force (geometricallytreated, as an improvement upon Whewell's algebraical method), investigation of the magnitude of attractive forces of glass, &c. , required to produce refraction. I forget about Mathematical Lectures;but I have an impression that I regularly attended Mr Peacock'slectures, and that he always set me some private problems. "I attended Mr Evans's lectures on St Luke: and I find many notesabout the history of the Jews, Cerinthus and various heresies, Paley'sMoral Philosophy, Paley's Evidences, and Biblical Maps: alsospeculations about ancient pronunciations. "For a week or more before the annual examination I was perfectlylazy. The Classes of my year (Junior Sophs) were not published tillJune 11. It was soon known that I was first with 2000 marks, the nextbeing Drinkwater with 1200 marks. After a short holiday at Bury andPlayford I returned to Cambridge on July 18th, 1821. My daily lifewent on as usual. I find that in writing Latin I began Cicero DeSenectute (retranslating Melmoth's translation, and comparing). Sometime in the Long Vacation the names of the Prizemen for Declamationswere published: I was disappointed that not one, English or Latin, wasassigned to me: but it was foolish, for my declamations were rathertrumpery. "My former pupil, Rosser, came again on August 14th. On August 29thDr Blomfield (afterwards Bishop of London) called, to engage me asTutor to his brother George Beecher Blomfield, and he commencedattendance on Sept. 1st. With these two pupils I finished at the endof the Long Vacation: for the next three terms I had one pupil, Gibson, a Newcastle man, recommended by Mr Peacock, I believe, as apersonal friend (Mr Peacock being of Durham). "The only classical subject appointed for the next examination was the5th, 6th and 7th Books of the Odyssey: the mathematical subjects allthe Applied Mathematics and Newton. There was to be however theScholarship Examination (Sizars being allowed to sit for Scholarshipsonly in their 3rd year: and the Scholarship being a kind of littleFellowship necessary to qualify for being a candidate for the realFellowship). "When the October term began Mr Hustler, who usually gave lectures inmathematics to his third-year pupils, said to me that it was not worthmy while to attend his lectures, and he or Mr Peacock suggested thatDrinkwater, Myers, and I should attend the Questionists'examinations. The Questionists are those who are to take the degree ofB. A. In the next January: and it was customary, not to give themlectures, but three times a week to examine them by settingmathematical questions, as the best method of preparing for theB. A. Examination. Accordingly it was arranged that we should attendthe said examinations: but when we went the Questionists of that yearrefused to attend. They were reported to be a weak year, and we to bea strong one: and they were disposed to take offence at us on anyoccasion. From some of the scholars of our year who sat at table withscholars of that year I heard that they distinguished us as 'theimpudent year, ' 'the annus mirabilis' &c. On this occasion theypretended to believe that the plan of our attendance at theQuestionists' examinations had been suggested by an undergraduate, andno explanation was of the least use. So the Tutors agreed not to pressthe matter on them: and instead of it, Drinkwater, Myers, and I wentthree times a week to Mr Peacock's rooms, and he set us questions. Ithink that this system was also continued during the next two terms(ending in June 1822) or part of them, but I am not certain. "In August 1821 I copied out a M. S. On Optics, I think from MrWhewell: on August 24th one on the Figure of the Earth and Tides; andat some other time one on the motion of a body round two centers offorce; both from Mr Whewell. On my scribbling paper I find--A problemon the vibrations of a gig as depending on the horse's step (like thatof a pendulum whose support is disturbed), Maclaurin's Attractions, Effect of separating the lenses of an achromatic object-glass(suggested by my old telescope), Barlow's theory of numbers, anddivision of the circle into 17 parts, partial differentials, theory ofeye-pieces, epicycloids, Figure of the Earth, Time of body in arc ofparabola, Problem of Sound, Tides, Refraction of Lens, includingthickness, &c. , Ivory's paper on Equations, Achromatism of microscope, Capillary Attraction, Motions of Fluids, Euler's principal axes, Spherical pendulum, Equation b²(d²y/dx²)=(d²y/dt²), barometer, LunarTheory well worked out, ordinary differential equations, Calculus ofVariations, Interpolations like Laplace's for Comets, Kepler'stheorem. In September I had my old telescope mounted on a short tripodstand, and made experiments on its adjustments. I was possessed ofWhite's Ephemeris, and I find observations of Jupiter and Saturn inOctober. I planned an engine for describing ellipses by the polarequation A/(1 + e cos theta) and tried to make a micrometer with silkthreads converging to a point. Mr Cubitt called on Oct. 4 and Nov. 1;he was engaged in erecting a treadmill at Cambridge Gaol, and had somethoughts of sending plans for the Cambridge Observatory, the erectionof which was then proposed. On Nov. 19 I find that I had received fromCubitt a Nautical Almanac, the first that I had. On Dec. 11 I madesome experiments with Drinkwater: I think it was whirling a glasscontaining oil on water. In Classics I was chiefly engaged uponThucydides and Homer. On October 6th I had a letter from CharlesMusgrave, introducing Challis, who succeeded me in the CambridgeObservatory in 1836. "At this time my poor afflicted father was suffering much from asevere form of rheumatism or pain in the legs which sometimesprevented him from going to bed for weeks together. "On the Commemoration Day, Dec. 18th, I received my prize asfirst-class man in Hall again. The next day I walked to Bury, andpassed the winter vacation there and at Playford. "I returned to Cambridge on Jan. 24th, 1822. On Feb. 12th I kept myfirst Act, with great compliments from the Moderator, and with a mostunusually large attendance of auditors. These disputations onmathematics, in Latin, are now discontinued. On March 20th I kept afirst Opponency against Sandys. About this time I received Buckle, aTrinity man of my own year, who was generally supposed to come nextafter Drinkwater, as pupil. On my sheets I find integrals anddifferential equations of every kind, astronomical corrections (ofwhich I prepared a book), chances, Englefield's comets, investigationof the brightness within a rainbow, proof of Clairaut's theorem in onecase, metacentres, change of independent variable applied to acomplicated case, generating functions, principal axes. On Apr. 8th Iintended to write an account of my eye: I was then tormented with adouble image, I suppose from some disease of the stomach: and on May28th I find by a drawing of the appearance of a lamp that the diseaseof my eye continued. "On Feb. 11th I gave Mr Peacock a paper on the alteration of the focallength of a telescope as directed with or against the Earth's orbitalmotion (on the theory of emissions) which was written out for readingto the Cambridge Philosophical Society on Feb. 24th and 25th. [ThisSociety I think was then about a year old. ] On Feb. 1 my MS. OnPrecession, Solar Inequality, and Nutation, was made complete. "The important examination for Scholarships was now approaching. As Ihave said, this one opportunity only was given to Sizars (Pensionershaving always two opportunities and sometimes three), and it isnecessary to be a Scholar in order to be competent to be a candidatefor a Fellowship. On Apr. 10th I addressed my formal Latin letter tothe Seniors. There were 13 vacancies and 37 candidates. The electiontook place on Apr. 18th, 1822. I was by much the first (which I hardlyexpected) and was complimented by the Master and others. Wrote theformal letter of thanks as usual. I was now entitled to claim betterrooms, and I took the rooms on the ground floor on the East side ofthe Queen's Gate of the Great Court. Even now I think of my quietresidence in the little rooms above the staircase in Neville's Courtwith great pleasure. I took possession of my new rooms on May 27th. "The Annual Examination began on May 30th. The Classes were publishedon June 5th, when my name was separated from the rest by two lines. Itwas understood that the second man was Drinkwater, and that my numberof marks was very nearly double of his. Having at this time beendisappointed of a proposed walking excursion into Derbyshire with acollege friend, who failed me at the last moment, I walked to Bury andspent a short holiday there and at Playford. "I returned to Cambridge on July 12th, 1822. I was steadily busyduring this Long Vacation, but by no means oppressively so: indeed mytime passed very happily. The Scholars' Table is the only one inCollege at which the regular possessors of the table are sure never tosee a stranger, and thus a sort of family intimacy grows up among theScholars. Moreover the Scholars feel themselves to be a privilegedclass 'on the foundation, ' and this feeling gives them a sort ofconceited happiness. It was the duty of Scholars by turns to readGrace after the Fellows' dinner and supper, and at this time (1848) Iknow it by heart. They also read the Lessons in Chapel on week days:but as there was no daily chapel-service during the summer vacation, Ihad not much of this. In the intimacy of which I speak I became muchacquainted with Drinkwater, Buckle, Rothman, and Sutcliffe: and weformed a knot at the table (first the Undergraduate Scholars' table, and afterwards the Bachelor Scholars' table) for several years. Duringthis Vacation I had for pupils Buckle and Gibson. "I wrote my daily Latin as usual, beginning with the retranslation ofCicero's Epistles, but I interrupted it from Sept. 27th to Feb. 8th. Ibelieve it was in this Vacation, or in the October term, that I beganevery evening to read Thucydides very carefully, as my notes aremarked 1822 and 1823. On August 27 I find that I was reading Ovid'sFasti. "In Mathematics I find the equation x + y = a, x^q + y^q = b, Caustics, Calculus of Variations, Partial Differentials, Aberration ofLight, Motions of Comets, various Optical constructions computed withspherical aberrations, Particular Solutions, Mechanics of SolidBodies, Attractions of Shells, Chances, Ivory's attraction-theorem, Lunar Theory (algebraical), Degrees across meridian, theoreticalrefraction, Newton's 3rd Book, Investigation of the tides in a shallowequatoreal canal, from which I found that there would be low-waterunder the moon, metacentres, rotation of a solid body round threeaxes, Attractions of Spheroids of variable density, finitedifferences, and complete Figure of the Earth. There is also a gooddeal of investigation of a mathematical nature not connected withCollege studies, as musical chords, organ-pipes, sketch for acomputing machine (suggested by the publications relating toBabbage's), sketch of machine for solving equations. In August thereis a plan of a MS. On the Differential Calculus, which it appears Iwrote then: one on the Figure of the Earth written about August 15th;one on Tides, Sept. 25th; one on Newton's Principia with algebraicaladditions, Nov. 1st. On Sept. 6th and 10th there are Lunar Distancesobserved with Rothman's Sextant and completely worked out; for these Iprepared a printed skeleton form, I believe my first. On December 13ththere are references to books on Geology (Conybeare and Phillips, andParkinson) which I was beginning to study. On July 27th, being the dayon which I completed my 21st year, I carefully did nothing. "Another subject partly occupied my thoughts, which, though not (withreference to practical science) very wise, yet gave me some Cambridgecelebrity. In July 1819 I had (as before mentioned) sketched a planfor constructing reflecting telescopes with silvered glass, and hadshewn it afterwards to Mr Peacock. I now completed the theory of thisconstruction by correcting the aberrations, spherical as well aschromatic. On July 13th, 1822, I drew up a paper about it for MrPeacock. He approved it much, and in some way communicated it to Mr(afterwards Sir John) Herschel. I was soon after introduced toHerschel at a breakfast with Mr Peacock: and he approved of the schemegenerally. On August 5th I drew up a complete mathematical paper forthe Cambridge Philosophical Society, which I entrusted to MrPeacock. The aberrations, both spherical and chromatic, are hereworked out very well. On Nov. 25th it was read at the meeting of thePhilosophical Society, and was afterwards printed in theirTransactions: this was my first printed Memoir. Before this timehowever I had arranged to try the scheme practically. Mr Peacock hadengaged to bear the expense, but I had no occasion to ask him. Partly(I think) through Drinkwater, I communicated with an optician namedBancks, in the Strand, who constructed the optical part. Isubsequently tried my telescope, but it would not do. The fault, as Ihad not and have not the smallest doubt, depends in some way on thecrystallization of the mercury silvering. It must have been about thistime that I was introduced to Mr (afterwards Sir James) South, at aparty at Mr Peacock's rooms. He advised me to write to Tulley, awell-known practical optician, who made me some new reflectors, &c. (so that I had two specimens, one Gregorian, the otherCassegrainian). However the thing failed practically, and I was toobusy ever after to try it again. "During the October term I had no pupils. I kept my second Act onNov. 6 (opponents Hamilton, Rusby, Field), and an Opponency againstJeffries on Nov. 7. I attended the Questionists' Examinations. I seemto have lived a very comfortable idle life. The Commemoration Day wasDec. 18th, when I received a Prize, and the next day I walked toBury. On Jan. 4th, 1823, I returned to Cambridge, and until theB. A. Examination I read novels and played cards more than at any othertime in College. "On Thursday, Jan. 9th, 1823, the preliminary classes, for arrangementof details of the B. A. Examination, were published. The first class, Airy, Drinkwater, Jeffries, Mason. As far as I remember, the rule wasthen, that on certain days the classes were grouped (in regard toidentity of questions given to each group) thus: 1st, {2nd/3rd}, {4th/5th} &c. , and on certain other days thus: {1st/2nd}, {3rd/4th}, &c. On Saturday, Jan. 11th, I paid fees. On Monday, Jan. 13th, theproceedings of examination began by a breakfast in the CombinationRoom. After this, Gibson gave me breakfast every day, and Buckle gaveme and some others a glass of wine after dinner. The hours were sharp, the season a cold one, and no fire was allowed in the Senate Housewhere the Examination was carried on (my place was in the Eastgallery), and altogether it was a severe time. "The course of Examination was as follows: "Monday, Jan. 13th. 8 to 9, printed paper of questions by Mr Hind(moderator); half-past 9 to 11, questions given orally; 1 to 3, ditto;6 to 9, paper of problems at Mr Higman's rooms. "Tuesday, Jan. 14th. 8 to 9, Higman's paper; half-past 9 to 11, questions given orally; 1 to 3, ditto; 6 to 9, paper of problems inSidney College Hall. "Wednesday, Jan. 15th. Questions given orally 8 to 9 and 1 to 3, withpaper of questions on Paley and Locke (one question only in each wasanswered). "Thursday, Jan. 16th. We went in at 9 and 1, but there seems to havebeen little serious examination. "Friday, Jan. 17. On this day the brackets or classes as resultingfrom the examination were published, 1st bracket Airy, 2nd bracketJeffries, 3rd bracket Drinkwater, Fisher, Foley, Mason, Myers. "On Saturday, Jan. 18th, the degrees were conferred in the usualway. It had been arranged that my brother and sister should come tosee me take my degree of B. A. , and I had asked Gibson to conduct themto the Senate House Gallery: but Mr Hawkes (a Trinity Fellow) foundthem and stationed them at the upper end of the Senate House. Afterthe preliminary arrangements of papers at the Vice-Chancellor's table, I, as Senior Wrangler, was led up first to receive the degree, andrarely has the Senate House rung with such applause as then filledit. For many minutes, after I was brought in front of theVice-Chancellor, it was impossible to proceed with the ceremony onaccount of the uproar. I gave notice to the Smith's Prize Electors ofmy intention to 'sit' for that prize, and dined at Rothman's roomswith Drinkwater, Buckle, and others. On Monday, Jan. 20th, I wasexamined by Professor Woodhouse, for Smith's Prize, from 10 to 1. Ithink that the only competitor was Jeffries. On Tuesday I was examinedby Prof. Turton, 10 to 1, and on Wednesday by Prof. Lax, 10 to 1. OnThursday, Jan. 23rd, I went to Bury by coach, on one of the coldestevenings that I ever felt. "Mr Peacock had once recommended me to sit for the Chancellor's medal(Classical Prize). But he now seemed to be cool in his advice, and Ilaid aside all thought of it. " * * * * * It seems not out of place to insert here a copy of some "CambridgeReminiscences" written by Airy, which will serve to explain the Actsand Opponencies referred to in the previous narrative, and othermatters. THE ACTS. The examination for B. A. Degrees was preceded, in my time, by keepingtwo Acts, in the Schools under the University Library: the second ofthem in the October term immediately before the examination; the first(I think) in the October term of the preceding year. These Acts were reliques of the Disputations of the Middle Ages, whichprobably held a very important place in the discipline of theUniversity. (There seems to be something like them in some of theContinental Universities. ) The presiding authority was one of theModerators. I apprehend that the word "Moderator" signified"President, " in which sense it is still used in the Kirk of Scotland;and that it was peculiarly applied to the Presidency of theDisputations, the most important educational arrangement in theUniversity. The Moderator sent a summons to the "Respondent" to submitthree subjects for argument, and to prepare to defend them on a givenday: he also named three Opponents. This and all the followingproceedings were conducted in Latin. For my Act of 1822, Nov. 6, Isubmitted the following subjects: "Recte statuit Newtonus in Principiis suis Mathematicis, libro primo, sectione undecimâ. " "Recte statuit Woodius de Iride. " "Recte statuit Paleius de Obligationibus. " The Opponents named to attack these assertions were Hamilton of StJohn's, Rusby of St Catharine's, Field of Trinity. It was customaryfor the Opponents to meet at tea at the rooms of the Senior Opponent, in order to discuss and arrange their arguments; the Respondent wasalso invited, but he was warned that he must depart as soon as teawould be finished: then the three Opponents proceeded with theiroccupation. As I have acted in both capacities, I am able to say thatthe matter was transacted in an earnest and business-like way. Indeedin the time preceding my own (I know not whether in my own time) theassistance of a private tutor was frequently engaged, and I rememberhearing a senior M. A. Remark that my College Tutor (James D. Hustler)was the best crammer for an Act in the University. At the appointed time, the parties met in the Schools: the Respondentfirst read a Latin Thesis on any subject (I think I took somemetaphysical subject), but nobody paid any attention to it: then theRespondent read his first Dogma, and the first Opponent produced anargument against it, in Latin. After this there were repeated repliesand rejoinders, all in vivâ voce Latin, the Moderator sometimesinterposing a remark in Latin. When he considered that one argumentwas disposed of, he called for another by the words "Probes aliter. "The arguments were sometimes shaped with considerable ingenuity, andrequired a clear head in the Respondent. When all was finished, theModerator made a complimentary remark to the Respondent and one to thefirst Opponent (I forget whether to the second and third). In myRespondency of 1822, November 6, the compliment was, "Quaestiones tuassummo ingenio et acumine defendisti, et in rebus mathematicisscientiam planè mirabilem ostendisti. " In an Opponency (I forgetwhen) the compliment was, "Magno ingenio argumenta tua et construxistiet defendisti. " The Acts of the high men excited much interest among the students. Atmy Acts the room was crowded with undergraduates. I imagine that, at a time somewhat distant, the maintenance of theActs was the only regulation by which the University acted on thestudies of the place. When the Acts had been properly kept, licensewas given to the Father of the College to present the undergraduate tothe Vice-Chancellor, who then solemnly admitted him "ad respondendumQuaestioni. " There is no appearance of collective examination beforethis presentation: what the "Quaestio" might be, I do not know. Stillthe undergraduate was not B. A. The Quaestio however was finished andapproved before the day of a certain Congregation, and then theundergraduate was declared to be "actualiter in artibus Baccalaureum. " Probably these regulations were found to be insufficient for thecontrol of education, and the January examination was instituted. Iconjecture this to have been at or shortly before the date of theearliest Triposes recorded in the Cambridge Calendar, 1748. The increasing importance of the January examination naturallydiminished the value of the Acts in the eyes of the undergraduates;and, a few years after my M. A. Degree, it was found that the Opponentsmet, not for the purpose of concealing their arguments from theRespondent, but for the purpose of revealing them to him. This led tothe entire suppression of the system. The most active man in thissuppression was Mr Whewell: its date must have been near to 1830. The shape in which the arguments were delivered by an Opponent, reading from a written paper, was, "Si (quoting something from theRespondent's challenge), &c. , &c. Cadit Quaestio; Sed (citingsomething else bearing on the subject of discussion), ValetConsequentia; Ergo (combining these to prove some inaccuracy in theRespondent's challenge), Valent Consequentia et Argumentum. " Nobodypretended to understand these mystical terminations. Apparently the original idea was that several Acts should be kept byeach undergraduate; for, to keep up the number (as it seemed), eachstudent had to gabble through a ridiculous form "Si quaestiones tuaefalsae sint, Cadit Quaestio:--sed quaestiones tuae falsae sunt, Ergovalent Consequentia et Argumentum. " I have forgotten time and placewhen this was uttered. THE SENATE-HOUSE EXAMINATION. The Questionists, as the undergraduates preparing for B. A. Were calledin the October term, were considered as a separate body; collected ata separate table in Hall, attending no lectures, but invited to attenda system of trial examinations conducted by one of the Tutors orAssistant-Tutors. From the Acts, from the annual College examinations, and (I suppose)from enquiries in the separate Colleges, the Moderators acquired ageneral idea of the relative merits of the candidates forhonours. Guided by this, the candidates were divided into sixclasses. The Moderators and Assistant Examiners were provided eachwith a set of questions in manuscript (no printed papers were used forHonours in the Senate House; in regard to the [Greek: hoi polloi] Icannot say). On the Monday on which the examination began, the Fatherof the College received all the Questionists (I believe), at any rateall the candidates for honours, at breakfast in the Combination Roomat 8 o'clock, and marched them to the Senate House. My place withother honour-men was in the East Gallery. There one Examiner tookcharge of the 1st and 2nd classes united, another Examiner took the3rd and 4th classes united, and a third took the 5th and 6thunited. On Tuesday, one Examiner took the 1st class alone, a secondtook the 2nd and 3rd classes united, a third took the 4th and 5thclasses united, and a fourth took the 6th class alone. On Wednesday, Thursday, and Friday the changes were similar. And, in all, thequestioning was thus conducted. The Examiner read from his manuscriptthe first question. Those who could answer it proceeded to write outtheir answers, and as soon as one had finished he gave the word"Done"; then the Examiner read out his second question, repeating itwhen necessary for the understanding by those who took it up morelately. And so on. I think that the same process was repeated in theafternoon; but I do not remember precisely. In this manner theExamination was conducted through five days (Monday to Friday) with nointerruption except on Friday afternoon. It was principally, perhapsentirely, bookwork. But on two _evenings_ there were printed papers of problems: and theexamination in these was conducted just as in the printed papers ofthe present day: but in the private College Rooms of theModerators. And there, wine and other refreshments were offered to theExaminees. How this singular custom began, I know not. The order of merit was worked out on Friday afternoon and evening, andwas in some measure known through the University late in theevening. I remember Mr Peacock coming to a party of Examinees andgiving information on several places. I do not remember his mentioningmine (though undoubtedly he did) but I distinctly remember his givingthe Wooden Spoon. On the Saturday morning at 8 o'clock the manuscriptlist was nailed to the door of the Senate-House. The form of furtherproceedings in the presentation for degree (ad respondendumquaestioni) I imagine has not been much altered. The kneeling beforethe Vice-Chancellor and placing hands in the Vice-Chancellor's handswere those of the old form of doing homage. The form of examination which I have described was complicated andperhaps troublesome, but I believe that it was very efficient, possibly more so than the modern form (established I suppose at thesame time as the abolition of the Acts). The proportion of questionsnow answered to the whole number set is ridiculously small, and noaccurate idea of relative merit can be formed from them. THE COLLEGE HALL. When I went up in 1819, and for several years later, the dinner was at1/4 past 3. There was no supplementary dinner for specialdemands. Boat-clubs I think were not invented, even in a plain socialway, till about 1824 or 1825; and not in connection with the Collegetill some years later. Some of the senior Fellows spoke of the timewhen dinner was at 2, and regretted the change. There was supper in Hall at 9 o'clock: I have known it to be attendedby a few undergraduates when tired by examinations or by eveningwalks; and there were always some seniors at the upper table: I haveoccasionally joined them, and have had some very interestingconversations. The supper was cold, but hot additions were made whenrequired. One little arrangement amused me, as shewing the ecclesiasticalcharacter of the College. The Fasts of the Church were to be strictlykept, and there was to be no dinner in Hall. It was thus arranged. Theevening chapel service, which was usually at 5-1/2 (I think), was heldat 3; and at 4 the ordinary full meal was served in Hall, but as itfollowed the chapel attendance it was held to be supper; and there wasno subsequent meal. There were no chairs whatever in Hall, except the single chair of thevice-master at the head of the table on the dais and that of thesenior dean at the table next the East wall. All others sat onbenches. And I have heard allusions to a ludicrous difficulty whichoccurred when some princesses (of the Royal Family) dined in the Hall, and it was a great puzzle how to get them to the right side of thebenches. The Sizars dined after all the rest; their dinner usually began soonafter 4. For the non-foundationists a separate dinner was provided, asfor pensioners. But for the foundationists, the remains of theFellows' dinner were brought down; and I think that this provision wasgenerally preferred to the other. The dishes at all the tables of undergraduates were of pewter, till acertain day when they were changed for porcelain. I cannot rememberwhether this was at the time when they became Questionists (in theOctober Term), or at the time when they were declared "actualiter essein artibus Baccalaureos" (in the Lent Term). Up to the Questionist time the undergraduate Scholars had no mixturewhatever; they were the only pure table in the Hall: and I looked onthis as a matter very valuable for the ultimate state of the Collegesociety. But in the October term, those who were to proceed toB. A. Were drafted into the mixed body of Questionists: and theygreatly disliked the change. They continued so till the Lent Term, when they were formally invited by the Bachelor Scholars to join theupper table. MATHEMATICAL SUBJECTS OF STUDY AND EXAMINATION. In the October Term 1819, the only books on Pure Mathematicswere:--Euclid generally, Algebra by Dr Wood (formerly Tutor, but in1819 Master, of St John's College), Vince's Fluxions and Dealtry'sFluxions, Woodhouse's and other Trigonometries. Not a whisper passedthrough the University generally on the subject of DifferentialCalculus; although some papers (subsequently much valued) on thatsubject had been written by Mr Woodhouse, fellow of Caius College; buttheir style was repulsive, and they never took hold of theUniversity. Whewell's Mechanics (1819) contains a few and easyapplications of the Differential Calculus. The books on appliedMathematics were Wood's Mechanics, Whewell's Mechanics, Wood's Optics, Vince's Hydrostatics, Vince's Astronomy, Woodhouse's Plane Astronomy(perhaps rather later), The First Book of Newton's Principia: I do notremember any others. These works were undoubtedly able; and for thegreat proportion of University students going into active life, I donot conceal my opinion that books constructed on the principles ofthose which I have cited were more useful than those exclusivelyfounded on the more modern system. For those students who aimed at themastery of results more difficult and (in the intellectual sense) moreimportant, the older books were quite insufficient. More aspiringstudents read, and generally with much care, several parts of Newton'sPrincipia, Book I. , and also Book III. (perhaps the noblest exampleof geometrical form of cosmical theory that the world has seen). Iremember some questions from Book III. Proposed in the Senate-HouseExamination 1823. In the October term 1819, I went up to the University. The works ofWood and Vince, which I have mentioned, still occupied thelecture-rooms. But a great change was in preparation for theUniversity Course of Mathematics. During the great Continental war, the intercourse between men of science in England and in France hadbeen most insignificant. But in the autumn of 1819, three members ofthe Senate (John Herschel, George Peacock, and Charles Babbage) hadentered into the mathematical society of Paris, and brought away someof the works on Pure Mathematics (especially those of Lacroix) and onMechanics (principally Poisson's). In 1820 they made a translation ofLacroix's Differential Calculus; and they prepared a volume ofExamples of the Differential and Integral Calculus. These wereextensively studied: but the form of the College Examinations or theUniversity Examinations was not, I think, influenced by them in thewinter 1820-1821 or the two following terms. But in the winter1821-1822 Peacock was one of the Moderators; and in the Senate-HouseExamination, January 1822, he boldly proposed a Paper of importantquestions entirely in the Differential Calculus. This was consideredas establishing the new system in the University. In January 1823, Ithink the two systems were mingled. Though I was myself subject tothat examination, I grieve to say that I have forgotten much of thedetails, except that I well remember that some of the questionsreferred to Newton, Book III. On the Lunar Theory. To these I havealready alluded. No other work occurs to me as worthy of mention, except Woodhouse'sLunar Theory, entirely founded on the Differential Calculus. The styleof this book was not attractive, and it was very little read. CHAPTER III. AT TRINITY COLLEGE, CAMBRIDGE, FROM HIS TAKING HIS B. A. DEGREE TO HIS TAKING CHARGE OF THE CAMBRIDGE OBSERVATORY AS PLUMIAN PROFESSOR. FROM JANUARY 18TH, 1823, TO MARCH 15TH, 1828. "On Jan. 30th, 1823, I returned to Cambridge. I had already heard thatI had gained the 1st Smith's Prize, and one of the first notificationsto me on my return was that the Walker's good-conduct prize of _£10_was awarded to me. "I remember that my return was not very pleasant, for our table inhall was half occupied by a set of irregular men who had lost termsand were obliged to reside somewhat longer in order to receive theB. A. Degree. But at the time of my completing the B. A. Degree (whichis not till some weeks after the examination and admission) I with theother complete bachelors was duly invited to the table of the B. A. Scholars, and that annoyance ended. "The liberation from undergraduate study left me at liberty generallyto pursue my own course (except so far as it was influenced by thepreparation for fellowship examination), and also left me at libertyto earn more money, in the way usual with the graduates, by takingundergraduate pupils. Mr Peacock recommended me to take only four, which occupied me four hours every day, and for each of them Ireceived 20 guineas each term. My first pupils, for the Lent andEaster terms, were Williamson (afterwards Head Master of WestminsterSchool), James Parker (afterwards Q. C. And Vice-Chancellor), Bissett, and Clinton of Caius. To all these I had been engaged before taking myB. A. Degree. "I kept up classical subjects. I have a set of notes on the [Greek:Ploutos] and [Greek: Nephelai] of Aristophanes, finished on Mar. 15th, 1823, and I began my daily writing of Latin as usual on Feb. 8th. Inmathematics I worked very hard at Lunar and Planetary Theories. I havetwo MS. Books of Lunar Theory to the 5th order of small quantities, which however answered no purpose except that of making me perfectlyfamiliar with that subject. I worked well, upon my quires, the figureof Saturn supposed homogeneous as affected by the attraction of hisring, and the figure of the Earth as heterogeneous, and the Calculusof Variations. I think it was now that I wrote a MS. On constrainedmotion. "On Mar. 17th, 1823, I was elected Fellow of the CambridgePhilosophical Society. On May 9th a cast of my head was taken for DrElliotson, an active phrenologist, by Deville, a tradesman in theStrand. "I had long thought that I should like to visit Scotland, and on myonce saying so to my mother, she (who had a most kindly recollectionof Alnwick) said in a few words that she thought I could not dobetter. I had therefore for some time past fully determined that assoon as I had sufficient spare time and money enough I would go toScotland. The interval between the end of Easter Term and the usualbeginning with pupils in the Long Vacation offered sufficient time, and I had now earned a little money, and I therefore determined to go, and invited my sister to accompany me. I had no privateintroductions, except one from James Parker to Mr Reach, a writer ofInverness: some which Drinkwater sent being too late. On May 20th wewent by coach to Stamford; thence by Pontefract and Oulton to York, where I saw the Cathedral, which _then_ disappointed me, but I supposethat we were tired with the night journey. Then by Newcastle toAlnwick, where we stopped for the day to see my birthplace. On May24th to Edinburgh. On this journey I remember well the stone wallsbetween the fields, the place (in Yorkshire) where for the first timein my life I saw rock, the Hambleton, Kyloe, Cheviot and PentlandHills, Arthur's Seat, but still more strikingly the revolving InchKeith Light. At Edinburgh I hired a horse and gig for our journey inScotland, and we drove by Queensferry to Kinross (where for the firsttime in my life I saw clouds on the hills, viz. On the Lomond Hills), and so to Perth. Thence by Dunkeld and Killicrankie to Blair Athol(the dreariness of the Drumochter Pass made a strong impression onme), and by Aviemore (where I saw snow on the mountains) toInverness. Here we received much kindness and attention from Mr Reach, and after visiting the Falls of Foyers and other sights we went toFort Augustus and Fort William. We ascended Ben Nevis, on which therewas a great deal of snow, and visited the vitrified fort in GlenNevis. Then by Inverary to Tarbet, and ascended Ben Lomond, fromwhence we had a magnificent view. We then passed by Loch Achray toGlasgow, where we found James Parker's brother (his father, of thehouse of Macinroy and Parker, being a wealthy merchant of Glasgow). OnJune 15th to Mr Parker's house at Blochairn, near Glasgow (on this dayI heard Dr Chalmers preach), and on the 17th went with the family bysteamer (the first that I had seen) to Fairly, near Largs. I returnedthe gig to Edinburgh, visited Arran and Bute, and we then went bycoach to Carlisle, and by Penrith to Keswick (by the old road: nevershall I forget the beauty of the approach to Keswick). After visitingAmbleside and Kendal we returned to Cambridge by way of Leeds, andposted to Bury on the 28th June. The expense of this expedition wasabout _£81_. It opened a completely new world to me. "I had little time to rest at Bury. In the preceding term Drinkwater, Buckle, and myself, had engaged to go somewhere into the country withpupils during the Long Vacation (as was customary with Cambridgemen). Buckle however changed his mind. Drinkwater went to look for aplace, fixed on Swansea, and engaged a house (called the CambrianHotel, kept by a Captain Jenkins). On the morning of July 2nd I leftBury for London and by mail coach to Bristol. On the morning of July3rd by steamer to Swansea, and arrived late at night. I had then fivepupils: Parker, Harman Lewis (afterwards Professor in King's College, London), Pierce Morton, Gibson, and Guest of Caius (afterwards Masterof the College). Drinkwater had four, viz. Two Malkins (from Bury), Elphinstone (afterwards M. P. ), and Farish (son of ProfessorFarish). We lived a hard-working strange life. My pupils began with meat six in the morning: I was myself reading busily. We livedcompletely _en famille_, with two men-servants besides the houseestablishment. One of our first acts was to order a four-oared boat tobe built, fitted with a lug-sail: she was called the Granta ofSwansea. In the meantime we made sea excursions with boats borrowedfrom ships in the port. On July 23rd, with a borrowed boat, we wentout when the sea was high, but soon found our boat unmanageable, andat last got into a place where the sea was breaking heavily over ashoal, and the two of the crew who were nearest to me (A. Malkin andLewis), one on each side, were carried out: they were good swimmersand we recovered them, though with some trouble: the breaker hadpassed quite over my head: we gained the shore and the boat was takenhome by land. When our own boat was finished, we had some mostpicturesque adventures at the Mumbles, Aberavon, Caswell Bay, Ilfracombe, and Tenby. From all this I learnt navigation prettywell. The mixture of hard study and open-air exertion seemed to affectthe health of several of us (I was one): we were covered with painfulboils. "My Latin-writing began again on July 25th: I have notes onDemosthenes, Lucretius, and Greek History. In mathematics I findChances, Figure of the Earth with variable density, DifferentialEquations, Partial Differentials, sketch for an instrument for shewingrefraction, and Optical instruments with effects of chromaticaberration. In August there occurred an absurd quarrel between theFellows of Trinity and the undergraduates, on the occasion ofcommencing the building of King's Court, when the undergraduates werenot invited to wine, and absented themselves from the hall. "There were vacant this year (1823) five fellowships in TrinityCollege. In general, the B. A. 's of the first year are not allowed tosit for fellowships: but this year it was thought so probable thatpermission would be given, that on Sept. 2nd Mr Higman, then appointedas Tutor to a third 'side' of the College, wrote to me to engage me asAssistant Mathematical Tutor in the event of my being elected a Fellowon Oct. 1st, and I provisionally engaged myself. About the same timeI had written to Mr Peacock, who recommended me to sit, and to MrWhewell, who after consultation with the Master (Dr Wordsworth), discouraged it. As there was no absolute prohibition, I left Swanseaon Sept. 11th (before my engagement to my pupils was quite finished)and returned to Cambridge by Gloucester, Oxford, and London. I gave inmy name at the butteries as candidate for fellowship, but was informedin a day or two that I should not be allowed to sit. On Sept. 19th Iwalked to Bury. "I walked back to Cambridge on Oct. 17th, 1823. During this Octoberterm I had four pupils: Neate, Cankrein, Turner (afterwards 2ndwrangler and Treasurer of Guy's Hospital), and William Hervey (son ofthe Marquis of Bristol). In the Lent term I had four (Neate, Cankrein, Turner, Clinton). In the Easter term I had three (Neate, Cankrein, Turner). "My daily writing of Latin commenced on Oct. 27th. In November I beganre-reading Sophocles with my usual care. In mathematics I findinvestigations of Motion in a resisting medium, Form of Saturn, Draftof a Paper about an instrument for exhibiting the fundamental law ofrefraction (read at the Philosophical Society by Mr Peacock onNov. 10th, 1823), Optics, Solid Geometry, Figure of the Earth withvariable density, and much about attractions. I also in this termwrote a MS. On the Calculus of Variations, and one on Wood's Algebra, 2nd and 4th parts. I have also notes of the temperature of mines inCornwall, something on the light of oil-gas, and reminiscences ofSwansea in a view of Oswick Bay. In November I attended ProfessorSedgwick's geological lectures. "At some time in this term I had a letter from Mr South (to whom Isuppose I had written) regarding the difficulty of my telescope: hewas intimately acquainted with Tulley, and I suppose that thus thematter had become more fully known to him. He then enquired if I couldvisit him in the winter vacation. I accordingly went from Bury, andwas received by him at his house in Blackman Street for a week or morewith great kindness. He introduced me to Sir Humphrey Davy and manyother London savans, and shewed me many London sights and theGreenwich Observatory. I also had a little practice with his owninstruments. He was then on intimate terms with Mr Herschel(afterwards Sir John Herschel), then living in London, who cameoccasionally to observe double stars. This was the first time that Isaw practical astronomy. It seems that I borrowed his mountainbarometer. In the Lent term I wrote to him regarding the deduction ofthe parallax of Mars, from a comparison of the relative positions ofMars and 46 Leonis, as observed by him and by Rumker at Paramatta. Myworking is on loose papers. I see that I have worked out perfectly theinterpolations, the effects of uncertainty of longitude, &c. , but I donot see whether I have a final result. "In Jan. 1824, at Playford, I was working on the effects of separatingthe two lenses of an object-glass, and on the kind of eye-piece whichwould be necessary: also on spherical aberrations and Saturn'sfigure. On my quires at Cambridge I was working on the effects ofseparating the object-glass lenses, with the view of correcting thesecondary spectrum: and on Jan. 31st I received some numbers (indicesof refraction) from Mr Herschel, and reference to Fraunhofer'snumbers. "About this time it was contemplated to add to the Royal Observatoryof Greenwich two assistants of superior education. Whether thisscheme was entertained by the Admiralty, the Board of Longitude, orthe Royal Society, I do not know. Somehow (I think through MrPeacock) a message from Mr Herschel was conveyed to me, acquainting meof this, and suggesting that I should be an excellent person for theprincipal place. To procure information, I went to London on Saturday, Feb. 7th, sleeping at Mr South's, to be present at one of Sir HumphreyDavy's Saturday evening soirées (they were then held every Saturday), and to enquire of Sir H. Davy and Dr Young. When I found thatsuccession to the post of Astronomer Royal was not considered asdistinctly a consequence of it, I took it coolly, and returned thenext night. The whole proposal came to nothing. "At this time I was engaged upon differential equations, mountainbarometer problem and determination of the height of the Gogmagogs andseveral other points, investigations connected with Laplace'scalculus, spherical aberration in different planes, geology(especially regarding Derbyshire, which I proposed to visit), and muchof optics. I wrote a draft of my Paper on the figure of Saturn, and onMar. 15th, 1824, it was read at the Philosophical Society under thetitle of 'On the figure assumed by a fluid homogeneous mass, whoseparticles are acted on by their mutual attraction, and by smallextraneous forces, ' and is printed in their Memoirs. I also wrote adraft of my Paper on Achromatic Eye-pieces, and on May 17th, 1824, itwas read at the Philosophical Society under the title of 'On thePrinciples and Construction of the Achromatic Eye-pieces ofTelescopes, and on the Achromatism of Microscopes, ' including also theeffects of separating the lenses of the object-glass. It is printed intheir Memoirs. "Amongst miscellaneous matters I find that on Mar. 22nd of this year Ibegan regularly making extracts from the books of the Book Society, apractice which I continued to March 1826. On Mar. 27th, a very rainyday, I walked to Bury to attend the funeral of my uncle WilliamBiddell, near Diss, and on Mar. 30th I walked back in rain andsnow. On Feb. 24th I dined with Cubitt in Cambridge. On May 21st Igave a certificate to Rogers (the assistant in Crosse's school, and myinstructor in mathematics), which my mother amplified much, and whichI believe procured his election as master of Walsall School. On June23rd I went to Bury. The speeches at Bury School, which I wished toattend, took place next day. " At this point of his Autobiography the writer continues, "Now came oneof the most important occurrences in my life. " The important event inquestion was his acquaintance with Richarda Smith, the lady whoafterwards became his wife. The courtship was a long one, and in theAutobiography there are various passages relating to it, all writtenin the most natural and unaffected manner, but of somewhat too privatea nature for publication. It will therefore be convenient to digressfrom the straight path of the narrative in order to insert a shortmemoir of the lady who was destined to influence his life andhappiness in a most important degree. Richarda Smith was the eldest daughter of the Rev. Richard Smith, whohad been a Fellow of Trinity College, Cambridge, but was at this timePrivate Chaplain to the Duke of Devonshire, and held the small livingof Edensor, near Chatsworth, in Derbyshire. He had a family of twosons and seven daughters, whom he had brought up and educated verycarefully. Several of his daughters were remarkable both for theirbeauty and accomplishments. Richarda Smith was now in her 20th year, and the writer of the Autobiography records that "at Matlock wereceived great attention from Mr Chenery: in speaking of Mr Smith Iremember his saying that Mr Smith had a daughter whom the Duke ofDevonshire declared to be the most beautiful girl he ever saw. " Thiswas before he had made the acquaintance of the family. Airy was atthis time on a walking tour in Derbyshire with his brother William, and they were received at Edensor by Mr Smith, to whom he had lettersof introduction. He seems to have fallen in love with Miss Smith "atfirst sight, " and within two days of first seeing her he made her anoffer of marriage. Neither his means nor his prospects at that timepermitted the least idea of an immediate marriage, and Mr Smith wouldnot hear of any engagement. But he never had the least doubt as tothe wisdom of the choice that he had made: he worked steadily on, winning fame and position, and recommending his suit from time to timeto Miss Smith as opportunity offered, and finally married her, nearlysix years after his first proposal. His constancy had its reward, forhe gained a most charming and affectionate wife. As he records at thetime of his marriage, "My wife was aged between 25 and 26, but shescarcely appeared more than 18 or 20. Her beauty and accomplishments, her skill and fidelity in sketching, and above all her exquisitesinging of ballads, made a great sensation in Cambridge. " Their married life lasted 45 years, but the last six years weresaddened by the partial paralysis and serious illness of LadyAiry. The entire correspondence between them was most carefullypreserved, and is a record of a most happy union. The letters werewritten during his numerous journeys and excursions on business orpleasure, and it is evident that his thoughts were with her from themoment of their parting. Every opportunity of writing was seized withan energy and avidity that shewed how much his heart was in thecorrespondence. Nothing was too trivial or too important tocommunicate to his wife, whether relating to family or businessmatters. The letters on both sides are always full of affection andsympathy, and are written in that spirit of confidence which arisesfrom a deep sense of the value and necessity of mutual support in thetroubles of life. And with his active and varied employments and hisnumerous family there was no lack of troubles. They were both of themsimple-minded, sensible, and practical people, and were very gratefulfor such comforts and advantages as they were able to command, but fornothing in comparison with their deep respect and affection for oneanother. Both by natural ability and education she was well qualified to enterinto the pursuits of her husband, and in many cases to assist him. Shealways welcomed her husband's friends, and by her skill and attractivecourtesy kept them well together. She was an admirable letter-writer, and in the midst of her numerous domestic distractions always foundtime for the duties of correspondence. In conversation she was veryattractive, not so much from the wit or brilliancy of her remarks asfrom the brightness and interest with which she entered into thetopics under discussion, and from the unfailing grace and courtesywith which she attended to the views of others. This was especiallyrecognized by the foreign astronomers and men of science who from timeto time stayed as guests at the Observatory and to whom she acted ashostess. Although she was not an accomplished linguist yet she waswell able to express herself in French and German, and her naturalgood sense and kindliness placed her guests at their ease, and madethem feel themselves (as indeed they were) welcomed and at home. Her father, the Rev. Richard Smith, was a man of most cultivated mind, and of the highest principles, with a keen enjoyment of good society, which the confidence and friendship of his patron the Duke ofDevonshire amply secured to him, both at Chatsworth and in London. Hehad a deep attachment to his Alma Mater of Cambridge, and though nothimself a mathematician he had a great respect for the science ofmathematics and for eminent mathematicians. During the long courtshipalready related Mr Smith conceived the highest respect for Airy'scharacter, as well as for his great repute and attainments, andexpressed his lively satisfaction at his daughter's marriage. Thus onJanuary 20th, 1830, he wrote to his intended son-in-law as follows: "Ihave little else to say to you than that I continue with heartfeltsatisfaction to reflect on the important change about to take place inmy dear daughter's situation. A father must not allow himself todilate on such a subject: of course I feel confident that you willhave no reason to repent the irrevocable step you have taken, but fromthe manner in which Richarda has been brought up, you will find such ahelpmate in her as a man of sense and affection would wish to have, and that she is well prepared to meet the duties and trials (for suchmust be met with) of domestic life with a firm and cultivated mind, and the warm feelings of a kind heart. Her habits are such as by nomeans to lead her to expensive wishes, nor will you I trust ever findit necessary to neglect those studies and pursuits upon which yourreputation and subsistence are chiefly founded, to seek for idleamusements for your companion. I must indulge no further in speakingof her, and have only at present to add that I commit in fullconfidence into your hands the guardianship of my daughter'shappiness. " And on April 5th, 1830, shortly after their marriage, hewrote to his daughter thus: "If thinking of you could supply yourplace amongst us you would have been with us unceasingly, for we haveall of us made you the principal object of our thoughts and our talksince you left us, and I travelled with you all your journey to yourpresent delightful home. We had all but one feeling of the purestpleasure in the prospect of the true domestic comfort to which wefully believe you to be now gone, and we rejoice that all yourendearing qualities will now be employed to promote the happiness ofone whom we think so worthy of them as your dear husband, who has leftus in the best opinion of his good heart, as well as his enlightenedand sound understanding. His late stay with us has endeared him to usall. Never did man enter into the married state from more honourablemotives, or from a heart more truly seeking the genuine happiness ofthat state than Mr Airy, and he will, I trust, find his reward in youfrom all that a good wife can render to the best of husbands, and hishappiness be reflected on yourself. " It would be difficult to findletters of more genuine feeling and satisfaction, or more eloquentlyexpressed, than these. The narrative of the Autobiography will now be resumed. "I had been disappointed two years before of an expedition toDerbyshire. I had wished still to make it, and my brother wished togo: and we determined to make it this year (1824). We were preparedwith walking dresses and knapsacks. I had well considered every detailof our route, and was well provided with letters of introduction, including one to the Rev. R. Smith of Edensor. On June 29th we startedby coach to Newmarket and walked through the Fens by Ramsay toPeterborough. Then by Stamford and Ketton quarries to Leicester andDerby. Here we were recognized by a Mr Calvert, who had seen me takemy degree, and he invited us to breakfast, and employed himself inshewing us several manufactories, &c. To which we had been deniedaccess when presenting ourselves unsupported. We then went to Belperwith an introduction from Mr Calvert to Jedediah Strutt: saw the greatcotton mills, and in the evening walked to Matlock. Up to this timethe country of greatest interest was the region of the fens aboutRamsay (a most remarkable district), but now began beauty of scenery. On July 9th we walked by Rowsley and Haddon Hall over the hills toEdensor, where we stayed till the 12th with Mr Smith. We next visitedHathersage, Castleton, and Marple (where I wished to see the canalaqueduct), and went by coach to Manchester, and afterwards toLiverpool. Here Dr Traill recommended us to see the PontycyssylteAqueduct, and we went by Chester and Wrexham to Rhuabon, saw themagnificent work, and proceeded to Llangollen. Thence by Chester andNorthwich (where we descended a salt-mine) to Macclesfield. Then tothe Ecton mine (of which we saw but little) through Dovedale toAshbourn, and by coach to Derby. On July 24th to Birmingham, where wefound Mr Guest, lodged in his house, and were joined by my pupilGuest. Here we were fully employed in visiting the manufactures, andthen went into the iron country, where I descended a pit in theStaffordshire Main. Thence by coach to Cambridge, where I stopped toprepare for the Fellowship Examination. "I had two pupils in this portion of the Long Vacation, Turner andDobbs. On August 2nd my writing of Latin began regularly as before. Myprincipal mathematics on the quires are Optics. On August 25th I madeexperiments on my left eye, with good measures, and on Aug. 26thordered a cylindrical lens of Peters, a silversmith in the town, whichI believe was never made. Subsequently, while at Playford, I orderedcylindrical lenses of an artist named Fuller, living at Ipswich, andthese were completed in November, 1824. "My letter to the Examiners, announcing my intention of sitting forFellowship (which like all other such documents is preserved on myquires) was delivered on Sept 21st. The Examination took place onSept. 22nd and the two following days. On Oct. 1st, 1824, at the usualhour of the morning, I was elected Fellow. There were elected at thesame time T. B. Macaulay (afterwards Lord Macaulay), who was a yearsenior to me in College, and I think Field of my own year. I drew upmy letter of acknowledgment to the Electors. On Oct. 2nd at 9 in themorning I was admitted Fellow with the usual ceremonies, and at 10 Icalled on the Electors with my letter of acknowledgment. I immediatelyjourneyed to Derbyshire, paid a visit at Edensor, and returned bySheffield. "On Oct. 11th (it having been understood with Mr Higman that myengagement as Assistant Mathematical Tutor stood) the Master sent forme to appoint me and to say what was expected as duty of theoffice. He held out to me the prospect of ultimately succeeding to theTutorship, and I told him that I hoped to be out of College beforethat time. "About this time the 'Athenaeum, ' a club of a scientific character, was established in London, and I was nominated on it, but I declined"(Oct. 14th). In this year (1824) I commenced account with a banker byplacing _£110_ in the hands of Messrs Mortlock and Co. On Oct. 16th Iwalked to Bury, and after a single day's stay there returned toCambridge. "On Oct. 23rd, 1824, 1 began my lectures as Mathematical AssistantTutor. I lectured the Senior Sophs and Junior Sophs on Higman'sside. The number of Senior Sophs was 21. Besides this I took part inthe 'Examinations of the Questionists, ' a series of exercises forthose who were to take the Bachelor's degree in the next January. Iexamined in Mechanics, Newton, and Optics. I had also as privatepupils Turner, Dobbs, and Cooper. I now ceased from the exercise whichI had followed with such regularity for five years, namely that ofdaily writing Latin. In its stead I engaged a French Master (Goussel)with whom I studied French with reasonable assiduity for the threeterms to June, 1825. "Among mathematical investigations I find: Theory of the Moon'sbrightness, Motion of a body in an ellipse round two centres of force, Various differential equations, Numerical computation of sin pi fromseries, Numerical computation of sines of various arcs to 18 decimals, Curvature of surfaces in various directions, Generating functions, Problem of sound. I began in the winter a Latin Essay as competingfor the Middle Bachelors' Prize, but did not proceed with it. Iafterwards wished that I had followed it up: but my time was fullyoccupied. "On Jan. 28th, 1825, I started for Edensor, where I paid a visit, andreturned on Feb. 2nd. On Feb. 4th I wrote to Mr Clarkson, asking hisadvice about a profession or mode of life (the cares of life were nowbeginning to press me heavily, and continued to do so for severalyears). He replied very kindly, but his answer amounted to nothing. About the same time I had some conversation of the same kind with MrPeacock, which was equally fruitless. "On Feb. 4th I have investigations of the density of light near acaustic (on the theory of emissions). On Feb. 5th I finished a Paperabout the defect in my eye, which was communicated to the CambridgePhilosophical Society on Feb. 21st. Mr Peacock or Mr Whewell had sometime previously applied to me to write a Paper on Trigonometry for theEncyclopaedia Metropolitana, and I had been collecting some materials(especially in regard to its history) at every visit to London, whereI read sometimes at the British Museum: also in the Cambridgelibraries. I began this Paper (roughly) on Feb. 8th, and finished iton Mar. 3rd. The history of which I speak, by some odd management ofthe Editors of the Encyclopaedia, was never published. The MS. Is nowamongst the MSS. Of the Royal Observatory, Greenwich. Other subjectson my quires are: Theory of musical concords, many things relating totrigonometry and trigonometrical tables, achromatic eye-pieces, equation to the surface bounding the rays that enter my left eye, experiments on percussion. Also notes on Cumberland and Wales (I hadalready proposed to myself to take a party of pupils in the LongVacation to Keswick), and notes on history and geology. "I had been in correspondence with Dr Malkin (master of Bury School), who on Feb. 8th sent a certificate for my brother William, whom Ientered at Trinity on Peacock's side. On Mar. 25th I changed my rooms, quitting those on the ground-floor east side of Queen Mary's Gate forfirst-floor rooms in Neville's Court, south side, the easternmostrooms. In this term my lectures lasted from Apr. 18th to May14th. Apparently I had only the Senior Sophs, 19 in number, and thesame four pupils (Turner, Dobbs, Cooper, Hovenden) as in the precedingterm. The only scientific subjects on which I find notes are, a Paperon the forms of the Teeth of Wheels, communicated to the PhilosophicalSociety on May 2nd; some notes about Musical Concords, and someexamination of a strange piece of Iceland Spar. On Apr. 29th I waselected to the Northern Institution (of Inverness); the firstcompliment that I received from an extraneous body. "On May 14th I have a most careful examination of my money accounts, to see whether I can make an expedition with my sister into Wales. Mysister came to Cambridge, and on Monday, May 23rd, 1825, we startedfor Wales, equipped in the lightest way for a walking expedition. Wewent by Birmingham to Shrewsbury: then to the Pontycyssylte Aqueductand by various places to Bala, and thence by Llanrwst to Conway. Herethe suspension bridge was under construction: the mole was made andthe piers, but nothing else. Then on to Bangor, where nine chains ofthe suspension bridge were in place, and so to Holyhead. Then byCarnarvon to Bethgelert, ascending Snowdon by the way, and insuccession by Festiniog, Dolgelly, and Aberystwyth to Hereford (thefirst time that I had visited it since my father left it). From thencewe went by coach to London, and I went on to Cambridge on the 23rd ofJune. "I had arranged to take a party of pupils to Keswick, and to take mybrother there. Mr Clarkson had provided me with introductions to MrSouthey and Mr Wordsworth. On Wednesday, June 29th, 1825, we started, and went by Leicester, Sheffield, Leeds, and Kendal, to Keswick, calling at Edensor on the way. My pupils were Cleasby, Marshman, Clinton, Wigram, Tottenham, and M. Smith. At Keswick I passed threemonths very happily. I saw Mr Southey's family frequently, and MrWordsworth's occasionally. By continual excursions in theneighbourhood, and by a few excursions to places as distant asBowness, Calder Bridge, &c. (always climbing the intermediatemountains), I became well acquainted with almost the whole of thatbeautiful country, excepting some of the S. W. Dales. A geologicalhammer and a mountain barometer were very interesting companions. Ihad plenty of work with my pupils: I worked a little Lunar Theory, alittle of Laplace's Equations, something of the Figure of the Earth, and I wrote out very carefully my Trigonometry for the EncyclopaediaMetropolitana. I read a little of Machiavelli, and various bookswhich I borrowed of Mr Southey. On Friday, Sept. 30th, my brother andI left for Kendal, and after a stay of a few days at Edensor, arrivedat Cambridge on Oct. 11th. "On Oct. 21st my Lectures to the Junior Sophs began, 39 names, lastingto Dec. 13th. Those to the Senior Sophs, 16 names, Oct 29th toDec. 10th. I also examined Questionists as last year. I have notesabout a Paper on the connection of impact and pressure, read at thePhilosophical Society on Nov. 14th, but not printed, dipping-needleproblems, curve described round three centres of force, barometerobservations, theory of the Figure of the Earth with variable density, and effect on the Moon, correction to the Madras pendulum, wedge withfriction, spots seen in my eyes, density of rays near a caustic. Inthis term I accomplished the preparation of a volume of MathematicalTracts on subjects which, either from their absolute deficiency in theUniversity or from the unreadable form in which they had beenpresented, appeared to be wanted. The subjects of my Tracts were, Lunar Theory (begun Oct. 26th, finished Nov. 1st), Figure of the Earth(1st part finished Nov. 18th), Precession and Nutation (my old MS. Putin order), and the Calculus of Variations. I applied, as is frequentlydone, to the Syndicate of the University Press for assistance inpublishing the work; and they agreed to give me paper and printing for500 copies. This notice was received from Professor Turton onNov. 29th, 1825. It was probably also in this year that I drew up animperfect 'Review' of Coddington's Optics, a work which deservedsevere censure: my review was never finished. "In the Long Vacation at Keswick I had six pupils at _£42_ each. Inthe October term I had Marshman and Ogilby at _£105_ for three terms, and Dobbs at _£75_ for three terms. I had, at Mr Peacock's suggestion, raised my rate from 60 to 100 guineas for three terms: this preventedsome from applying to me, and induced some to withdraw who had beenconnected with me: but it did me no real hurt, for engrossment bypupils is the worst of all things that can happen to a man who hopesto distinguish himself. On Dec. 17th I went to Bury, and returned toCambridge on Jan. 30th, 1826. "I have the attendance-bills of my Lectures to Senior Sophs (16) fromFeb. 3rd to Feb. 23rd, and to Freshmen (40) from Feb. 27th toMar. 15. It would appear that I gave but one college-lecture per day(my belief was that I always had two). The tutor's stipend per termwas _£50_. On my quires I find, Investigations for the ellipticity ofa heterogeneous spheroid when the density is expressed by sin_qc_/_qc_ (the remarkable properties of which I believe I discoveredentirely myself, although they had been discovered by other persons), Theoretical Numbers for precession, nutation, &c. , some investigationsusing Laplace's Y, hard work on the Figure of the Earth to the 2ndorder, 'Woodhouse's remaining apparatus, ' Notes about Lambton's andKater's errors, Depolarization, Notes of Papers on depolarization inthe Phil. Trans. , Magnetic Investigations for Lieut. Foster, Isochronous Oscillations in a resisting medium, Observations on astrange piece of Iceland Spar. On Mar. 7th forwarded Preface and TitlePage for my Mathematical Tracts. "Some time in this term I began to think of the possibility ofobserving the diminution of gravity in a deep mine, and communicatedwith Whewell, who was disposed to join in experiments. My first notionwas simply to try the rate of a clock, and the Ecton mine was firstthought of. I made enquiries about the Ecton mine through Mr Smith (ofEdensor), and visited the mine, but in the meantime Whewell had madeenquiries in London and found (principally from Dr Paris) that themine of Dolcoath near Camborne in Cornwall would be a better place forthe experiment. Dr Paris wrote to me repeatedly, and ultimately weresolved on trying it there. In my papers on Mar. 21st are variousinvestigations about attractions in both mines. On Apr. 3rd I went toLondon, principally to arrange about Dolcoath, and during April andMay I was engaged in correspondence with Sir H. Davy (President ofthe Royal Society), Mr Herschel, and Dr Young (Secretary of the Boardof Longitude) about the loan of instruments and pendulums. OnApr. 23rd I was practising pendulum-observations (by coincidence); andabout this time repeatedly practised transits with a small instrumentlent by Mr Sheepshanks (with whom my acquaintance must have begun nolong time before) which was erected under a tent in the Fellows'Walks. On my quires I find various schemes for graduating thermometersfor pendulum experiments. "I find also Notes of examination of my brother William, who had cometo College last October; and a great deal of correspondence with mymother and sister and Mr Case, a lawyer, about a troublesome businesswith Mr Cropley, an old friend of G. Biddell, to whom my father hadlent _£500_ and whose affairs were in Chancery. "My lectures in this term were to the Junior Sophs from Apr. 10th toMay 13th: they were six in number and not very regular. On Apr. 28th Isent to Mawman the copy of my Trigonometry for the EncyclopaediaMetropolitana, for which I received _£42_. I received notice from thePress Syndicate that the price of my Mathematical Tracts was fixed at_6s. 6d. _: I sold the edition to Deighton for _£70_, and it wasimmediately published. About this time I have letters from Mr Herscheland Sir H. Davy about a Paper to be presented to the Royal Society--Isuppose about the Figure of the Earth to the 2nd order of ellipticity, which was read to the Royal Society on June 15th. "On Saturday, May 13th, 1826, I went to London on the way to Dolcoath, and received four chronometers from the Royal Observatory, Greenwich. I travelled by Devonport and Falmouth to Camborne, where Iarrived on May 20th and dined at the count-house dinner at the mine. Iwas accompanied by Ibbotson, who was engaged as a pupil, and intendedfor an engineer. On May 24th Whewell arrived, and we took a pendulumand clock down, and on the 30th commenced the observation ofcoincidences in earnest. This work, with the changing of thependulums, and sundry short expeditions, occupied nearly threeweeks. We had continued the computation of our observations at everypossible interval. It is to be understood that we had one detachedpendulum swinging in front of a clock pendulum above, and anothersimilarly mounted below; and that the clocks were compared bychronometers compared above, carried down and compared, comparedbefore leaving, and brought up and compared. The upper and lowerpendulums had been interchanged. It was found now that the relianceon the steadiness of the chronometers was too great; and a new methodwas devised, in which for each series the chronometers should makefour journeys and have four comparisons above and two below. Thisarrangement commenced on the 19th June and continued till the 20th. Onthe 26th we packed the lower instruments, intending to compare thependulum directly with the upper one, and sent them up the shaft: whenan inexplicable occurrence stopped all proceedings. The basketcontaining all the important instruments was brought up to the surface(in my presence) on fire; some of the instruments had fallen out withtheir cases burning. Whether a superstitious miner had intentionallyfired it, or whether the snuff of a candle had been thrown into it, isnot known. Our labour was now rendered useless. On the 28th I packedup what remained of instruments, left for Truro, and arrived at Buryon July 1st. During our stay in Cornwall I had attended a 'ticketing'or sale of ore at Camborne, and we had made expeditions to theN. W. Coast, to Portreath and Illogan, to Marazion and St Michael'sMount, and to Penzance and the Land's End. On July 3rd I saw MrCropley in Bury gaol, and went to Cambridge. On the 4th I was admittedA. M. , and on the 5th was admitted Major Fellow. "I had engaged with four pupils to go to Orléans in this LongVacation: my brother William was also to go. One of my pupils, Dobbs, did not join: the other three were Tinkler, Ogilby, and Ibbotson. Weleft London on July 9th, and travelled by Brighton, Dieppe, Rouen, andParis to Orléans. At Paris I saw Bouvard, Pouillet, Laplace andArago. I had introductions from Mr Peacock, Mr South, Mr Herschel, DrYoung; and from Professor Sedgwick to an English resident, MrUnderwood. On the 19th I was established in the house of M. Lagarde, Protestant Minister. Here I received my pupils. On the 28th Icommenced Italian with an Italian master: perhaps I might have donemore prudently in adhering to French, for I made no great progress. OnAug. 2nd I saw a murderer guillotined in the Place Martroi. Theprincipal investigations on my quires are--Investigations aboutpendulums, Calculus of Variations, Notes for the Figure of the Earth(Encyc. Metrop. ) and commencement of the article, steam-enginemachinery, &c. I picked up various French ballads, read various books, got copies of the Marseillaise (this I was obliged to obtain rathersecretly, as the legitimist power under Charles X. Was then at itsheight) and other music, and particulars of farm wages for Whewell andR. Jones. The summer was intensely hot, and I believe that the heatand the work in Dolcoath had weakened me a good deal. The family wasthe old clergyman, his wife, his daughter, and finally his son. Welived together very amicably. My brother lodged in a Café in the PlaceMartroi; the others in different families. I left Orléans onSept. 30th for Paris. Here I attended the Institut, and was present atone of Ampère's Lectures. I arrived at Cambridge on Oct. 14th. "On Oct. 16th Whewell mentioned to me that the Lucasian Professorshipwould be immediately vacated by Turton, and encouraged me to competefor it. Shortly afterwards Mr Higman mentioned the Professorship, andJoshua King (of Queens') spoke on the restriction which preventedCollege tutors or Assistant tutors from holding the office. Aboutthis time Mr Peacock rendered me a very important service. As theemolument of the Lucasian Professorship was only _£99_, and that ofthe Assistant Tutorship _£150_, I had determined to withdraw from thecandidature. But Mr Peacock represented to me the advantage ofposition which would be gained by obtaining the Professorship (which Ithen instantly saw), and I continued to be a candidate. I wroteletters to the Heads of Colleges (the electors) and canvassed thempersonally. Only Dr Davy, the Master of Caius College, at oncepromised me his vote. Dr French, Master of Jesus College, was acandidate; and several of the Heads had promised him their votes. MrBabbage, the third candidate, threatened legal proceedings, and DrFrench withdrew. The course was now open for Mr Babbage and me. "In the meetings of the Philosophical Society a new mode of proceedingwas introduced this term. To enliven the meetings, private memberswere requested to give oral lectures. Mine was the second, I think, and I took for subject The Machinery of the Steam Engines in theCornish mines, and especially of the Pumping Engines and Pumps. Itmade an excellent lecture: the subjects were at that time undescribedin books, and unknown to engineers in general out of Cornwall. "My College lectures seem to have been, Oct. 21st to Dec. 14th to 31Junior Sophs, Dec. 4th to 12th to 12 Senior Sophs. I assisted at theexaminations of the Questionists. I had no private pupils. OnNov. 26th I communicated to the Cambridge Philosophical Society aPaper on the Theory of Pendulums, Balances, and Escapements: and Ifind applications of Babbage's symbolism to an escapement which Iproposed. I have various investigations about the Earth, supposed toproject at middle latitudes above the elliptical form. In November anaccount of the Dolcoath failure (by Whewell) was given to the RoyalSociety. "At length on Dec. 7th, 1826, the election to the LucasianProfessorship took place: I was elected (I think unanimously) andadmitted. I believe that this gave great satisfaction to theUniversity in general. My uncle, Arthur Biddell, was in Cambridge onthat evening, and was the first of my friends who heard of it. On thesame page of my quires on which this is mentioned, there is a greatlist of apparatus to be constructed for Lucasian Lectures, notes ofexperiments with Atwood's Machine, &c. In December, correspondencewith Dollond about prisms. I immediately issued a printed notice thatI would give professorial lectures in the next Term. "On Dec. 13th I have a letter from Mr Smith informing me of thedangerous illness (fever) which had attacked nearly every member ofhis family, Richarda worst of all. On Dec. 23rd I went to Bury. Theaffairs with Cropley had been settled by the sale of his propertyunder execution, and my father did not lose much of his debt. But hehad declined much in body and mind, and now had strangehallucinations. "The commencement of 1827 found me in a better position (not in moneybut in prospects) than I had before stood in: yet it was far fromsatisfactory. I had resigned my Assistant Tutorship of _£150_ perannum together with the prospect of succeeding to a Tutorship, andgained only the Lucasian Professorship of _£99_ per annum. I had agreat aversion to entering the Church: and my lay fellowship wouldexpire in 7 years. My prospects in the law or other professions mighthave been good if I could have waited: but then I must have been in astate of starvation probably for many years, and marriage would havebeen out of the question: I much preferred a moderate income in nolong time, and I am sure that in this I judged rightly for myhappiness. I had now in some measure taken science as my line (thoughnot irrevocably), and I thought it best to work it well, for a time atleast, and wait for accidents. "The acceptance of the Lucasian Professorship prevented me from beingpressed by Sedgwick (who was Proctor this year) to take the office ofmoderator: which was a great relief to me. As Lucasian Professor I wasipso facto Member of the Board of Longitude. A stipend of _£100_ ayear was attached to this, on condition of attending four meetings:but I had good reason (from intimations by South and other persons inLondon) for believing that this would not last long. The fortnightlynotices of the meetings of the Board were given on Jan. 18th, Mar. 22nd, May 24th and Oct. 18th. "On Jan. 2nd, 1827, I came from London to Bury. I found my father in avery declining state (the painful rheumatism of some years had changedto ulcerations of the legs, and he was otherwise helpless and haddistressing hallucinations). On Jan. 8th I walked to Cambridge. Atboth places I was occupied in preparations for the Smith's PrizeExamination and for lectures (for the latter I obtained at Bury gaolsome numerical results about tread-mills). "Of the Smith's Prize I was officially an Examiner: and I determinedto begin with---what had never been done before--making theexamination public, by printing the papers of questions. The Prize isthe highest Mathematical honour in the University: the competitors areincepting Bachelors of Arts after the examination for that Degree. Myday of examination (apparently) was Jan. 21st. The candidates wereTurner, Cankrein, Cleasby, and Mr Gordon. The first three had been myprivate pupils: Mr Gordon was a Fellow-commoner of St Peter's College, and had just passed the B. A. Examination as Senior Wrangler, Turnerbeing second. My situation as Examiner was rather a delicate one, andthe more so as, when I came to examine the papers of answers, Turnerappeared distinctly the first. Late at night I carried the papers toWhewell's rooms, and he on inspection agreed with me. The otherexaminers (Professors Lax and Woodhouse, Lowndean and PlumianProfessors) generally supported me: and Turner had the honour of FirstSmith's Prize. "On Jan. 30th my mother wrote, asking if I could see Cropley inLondon, where he was imprisoned for contempt of Chancery. I attendedthe meeting of the Board of Longitude on Feb. 1st, and afterwardsvisited Cropley in the Fleet Prison. He died there, some timelater. It was by the sale of his effects under execution that myfather's debt was paid. "On Feb. 15th I communicated to the Royal Society a Paper on thecorrection of the Solar Tables from South's observations. I believethat I had alluded to this at the February meeting of the Board ofLongitude, and that in consequence Mr Pond, the Astronomer Royal, hadbeen requested to prepare the errors of the Sun's place from theGreenwich observations: which were supplied some months later. Withthe exception of South's Solar Errors, and some investigations aboutdipping-needles, I do not find anything going on but matters connectedwith my approaching lectures. There are bridges, trusses, and othermechanical matters, theoretical and practical, without end. Severaltradesmen in Cambridge and London were well employed. On Feb. 13th Ihave a letter from Cubitt about groins: I remember studying those ofthe Custom-house and other places. On Feb. 20th my Syllabus ofLectures was finished: this in subsequent years was greatlyimproved. I applied to the Royal Society for the loan of Huyghens'sobject-glass, but they declined to lend it. About this time I findobservations of the spectrum of Sirius. "There had been no lectures on Experimental Philosophy (Mechanics, Hydrostatics, Optics) for many years. The University in general, Ibelieve, looked with great satisfaction to my vigorous beginning:still there was considerable difficulty about it. There was nounderstood term for the Lectures: no understood hour of the day: nounderstood lecture room. I began this year in the Lent Term, but inall subsequent years I took the Easter Term, mainly for the chance ofsunlight for the optical experiments, which I soon made important. Icould get no room but a private or retiring room (not a regularlecture room) in the buildings at the old Botanic Garden: in followingyears I had the room under the University Library. The Lecturescommenced on some day in February 1827: I think that the number whoattended them was about 64. I remember very well that the matter whichI had prepared as an Introductory Lecture did not last above half thetime that I had expected, but I managed very well to fill up thehour. On another occasion I was so ill-prepared that I hadcontemplated giving notice that I was unable to complete the hour'slecture, but I saw in the front row some strangers, introduced by someof my regular attendants, very busy in taking notes, and as it wasevident that a break-down now would not do, I silently exerted myselfto think of something, and made a very good lecture. "On Mar. 1st, as official examiner, I received notices from 14candidates for Bell's Scholarships, and prepared my Paper ofquestions. I do not remember my day of examination; but I had all theanswers to all the examiners' questions in my hands, when on Mar. 27thI received notice that my father had died the preceding evening. Thisstopped my Lectures: they were concluded in the next term. I thinkthat I had only Mechanics and imperfect Optics this term, noHydrostatics; and that the resumed Lectures were principallyOptical. They terminated about May 14th. "With my brother I at once went to Bury to attend my father'sfuneral. He was buried on Mar. 31st, 1827, in the churchyard of LittleWhelnetham, on the north side of the church. Shortly afterwards I wentto London, and on Apr. 5th I attended a meeting of the Board ofLongitude, at which Herschel produced a Paper regarding improvementsof the Nautical Almanac. Herschel and I were in fact the leaders ofthe reforming party in the Board of Longitude: Dr Young the Secretaryresisted change as much as possible. After the meeting I went toCambridge. I find then calculations of achromatic eye-pieces for avery nice model with silk threads of various colours which I made withmy own hands for my optical lectures. "On Apr. 7th Herschel wrote to me that the Professorship held by DrBrinkley (then appointed Bishop of Cloyne) at Dublin would be vacant, and recommended it to my notice, and sent me some introductions. Ireached Dublin on Apr. 15th, where I was received with great kindnessby Dr Brinkley and Dr MacDonnell (afterwards Provost). I there met thethen Provost Dr Bartholomew Lloyd, Dr Lardner, Mr Hamilton (afterwardsSir W. R. Hamilton) and others. In a few days I found that theygreatly desired to appoint Hamilton if possible (they did in factovercome some difficulties and appoint him in a few months), and thatthey would not make such an augmentation as would induce me to offermyself as a candidate, and I withdrew. I have always remembered withgratitude Dr MacDonnell's conduct, in carefully putting me on a fairfooting in this matter. I returned by Holyhead, and arrived atBirmingham on Apr. 23rd. While waiting there and looking over somepapers relating to the spherical aberration of eye-pieces, in which Ihad been stopped some time by a geometrical difficulty, I did in thecoffee-room of a hotel overcome the difficulty; and this was thefoundation of a capital paper on the Spherical Aberration ofEye-pieces. This paper was afterwards presented to the CambridgePhilosophical Society. "About this time a circumstance occurred of a disagreeable nature, which however did not much disconcert me. Mr Ivory, who had a goodmany years before made himself favourably known as a mathematician, especially by his acquaintance with Laplace's peculiar analysis, hadadopted (as not unfrequently happens) some singular hydrostaticaltheories. In my last Paper on the Figure of the Earth, I had said thatI could not receive one of his equations. In the PhilosophicalMagazine of May he attacked me for this with great heat. On May 8th Iwrote an answer, and I think it soon became known that I was not to beattacked with impunity. "Long before this time there had been some proposal about an excursionto the Lake District with my sister, and I now arranged to carry itout. On May 23rd I went to Bury and on to Playford: while there Isketched the Cumberland excursion. On June 5th I went to London, Ibelieve to the Visitation of the Greenwich Observatory to which I wasinvited. I also attended the meeting of the Board of Longitude. Ithink it was here that Pond's Errors of the Sun's place in theNautical Almanac from Greenwich Observations were produced. On June7th I went by coach to Rugby, where I met my sister, and we travelledto Edensor. We made a number of excursions in Derbyshire, and thenpassed on by Penrith to Keswick, where we arrived on June 22nd. FromKeswick we made many excursions in the Lake District, visited MrSouthey and Mr Wordsworth, descended a coal mine at Whitehaven, andreturned to Edensor by the way of Ambleside, Kendal, and Manchester. With sundry excursions in Derbyshire our trip ended, and we returnedto Cambridge on the 21st July. "During this Long Vacation I had one private pupil, Crawford, the onlypupil this year, and the last that I ever had. At this time there ison my papers an infinity of optical investigations: also a plan of aneye-piece with a concave lens to destroy certain aberrations. OnAug. 20th I went to Woodford to see Messrs Gilbert's opticalworks. From Aug. 13th I had been preparing for the discussion of theGreenwich Solar Errors, and I had a man at work in my rooms, engagedon the calculation of the Errors. I wrote to Bouvard at Paris forobservations of the sun, but he recommended me to wait for the Tableswhich Bessel was preparing. I was busy too about my Lectures: onSept. 29th I have a set of plans of printing presses from Hansard theprinter (who in a visit to Cambridge had found me making enquiriesabout them), and I corresponded with Messrs Gilbert about opticalconstructions, and with W. And S. Jones, Eastons, and others aboutpumps, hydraulic rams, &c. On Sept. 25th occurred a very magnificentAurora Borealis. "I do not find when the investigation of Corrections of Solar Elementswas finished, or when my Extracts from Burckhardt, Connaissance desTemps 1816, were made. But these led me to suspect an unknowninequality in the Sun's motion. On Sept. 27th and 28th I find thefirst suspicions of an inequality depending on 8 × mean longitude ofVenus--13 × mean longitude of Earth. The thing appeared so promisingthat I commenced the investigation of the perturbation related to thisterm, and continued it (a very laborious work) as fast as I was able, though with various interruptions, which in fact were necessary tokeep up my spirits. On Oct. 30th I went to London for the Board ofLongitude meeting. Here I exhibited the results of my Suninvestigations, and urged the correction of the elements used in theNautical Almanac. Dr Young objected, and proposed that Bouvard shouldbe consulted. Professor Woodhouse, the Plumian Professor, was present, and behaved so captiously that some members met afterwards to considerhow order could be maintained. I believe it was during this visit toLondon that I took measures of Hammersmith Suspension Bridge for anintended Lecture-model. Frequently, but not always, when in London, Iresided at the house of Mr Sheepshanks and his sister MissSheepshanks, 30 Woburn Place. My quires, at this time, abound withsuggestions for lectures and examinations. "On some day about the end of November or beginning of December 1827, when I was walking with Mr Peacock near the outside gate of theTrinity Walks, on some mention of Woodhouse, the Plumian Professor, MrPeacock said that he was never likely to rise into activity again (orusing some expression importing mortal illness). Instantly there hadpassed through my mind the certainty of my succeeding him, the goodposition in which I stood towards the University, the probability ofthat position being improved by improved lectures, &c. , &c. , and byincreased reputation from the matters in which I was now engaged, thepower of thus commanding an increase of income. I should then have, independent of my Fellowship, some competent income, and a house overmy head. I was quite aware that some time might elapse, but now forthe first time I saw my way clearly. The care of the Observatory hadbeen for two or three years attached to the Plumian Professorship. AGrace was immediately prepared, entrusting the temporary care of theObservatory to Dr French, to me, Mr Catton, Mr Sheepshanks, and MrKing (afterwards Master of Queens' College). On Dec. 6th I have a notefrom Mr King about going to the Observatory. "On Dec. 6th my Paper on corrections of the elements of the SolarTables was presented to the Royal Society. On Dec. 9th, at 1 h. 4m. A. M. (Sunday morning), I arrived at the result of my calculationsof the new inequality. I had gone through some fluctuations offeeling. Usually the important part of an inequality of this kinddepends entirely on the eccentricities of the orbits, but it sohappened that from the positions of the axes of the orbits, &c. , theseterms very nearly destroyed each other. After this came theconsideration of inclinations of orbits; and here were sensible termswhich were not destroyed. Finally I arrived at the result that theinequality would be about 3"; just such a magnitude as was required. Islipped this into Whewell's door. This is, to the time of writing(1853), the last improvement of any importance in the SolarTheory. Some little remaining work went on to Dec. 14th, and then, being thoroughly tired, I laid by the work for revision at some futuretime. I however added a Postscript to my Royal Society Paper on SolarErrors, notifying this result. "On Dec. 19th I went to Bury. While there I heard from Whewell thatWoodhouse was dead. I returned to Cambridge and immediately made knownthat I was a candidate for the now vacant Plumian Professorship. Ofmiscellaneous scientific business, I find that on Oct. 13th ProfessorBarlow of Woolwich prepared a memorial to the Board of Longitudeconcerning his fluid telescope (which I had seen at Woodford), whichwas considered on Nov. 1st, and I had some correspondence with him inDecember. In June and August my Trigonometry was printing. "On Jan. 5th, 1828, I came from London. It seems that I had beenspeculating truly 'without book' on perturbations of planetaryelements, for on Jan. 17th and 18th I wrote a Paper on a supposederror of Laplace, and just at the end I discovered that he was quiteright: I folded up the Paper and marked it 'A Lesson. ' I set twopapers of questions for Smith's Prizes (there being a deficiency ofone Examiner, viz. The Plumian Professor). "Before the beginning of 1828 Whewell and I had determined onrepeating the Dolcoath experiments. On Jan. 8th I have a letter fromDavies Gilbert (then President of the Royal Society) congratulating meupon the Solar Theory, and alluding to our intended summer's visit toCornwall. We had somehow applied to the Board of Longitude forpendulums, but Dr Young wished to delay them, having with Capt. BasilHall concocted a scheme for making Lieut. Foster do all the work:Whewell and I were indignant at this, and no more was said aboutit. On Jan. 24th Dr Young, in giving notice of the Board of Longitudemeeting, informs me that the clocks and pendulums are ready. "I had made known that I was a candidate for the PlumianProfessorship, and nobody thought it worth while to oppose me. Oneperson at least (Earnshaw) had intended to compete, but he called onme to make certain that I was a candidate, and immediately withdrew. Iwent on in quality of Syndic for the care of the Observatory, ingrafting myself into it. But meantime I told everybody that thesalary (about _£300_) was not sufficient for me; and on Jan. 20th Idrafted a manifesto or application to the University for an increaseof salary. The day of election to the Professorship was Feb. 6th. As Iwas officially (as Lucasian Professor) an elector, I was present, andI explained to the electors that I could not undertake theresponsibility of the Observatory without augmentation of income, andthat I requested their express sanction to my application to theUniversity for that purpose. They agreed to this generally, and I waselected. I went to London immediately to attend a meeting of theBoard of Longitude and returned on Feb. 8th. On Feb. 15th I began myLectures (which, this year, included Mechanics, Optics, Pneumatics, and Hydrostatics) in the room below the University Library. The numberof names was 26. The Lectures terminated on Mar. 22nd. "On Feb. 25th I received from Mr Pond information on the emoluments atGreenwich Observatory. I drew up a second manifesto, and on Feb. 26thI wrote and signed a formal copy for the Plumian electors. OnFeb. 27th I met them at Caius Lodge (the Master, Dr Davy, beingVice-Chancellor). I read my Paper, which was approved, and theirsanction was given in the form of a request to the Vice-Chancellor topermit the paper to be printed and circulated. My paper, with thisrequest at the head, was immediately printed, and a copy was sent toevery resident M. A. (more than 200 went out in one day). The statementand composition of the paper were generally approved, but theUniversity had never before been taken by storm in such a manner, andthere was some commotion about it. I believe that very few personswould have taken the same step. Mr Sheepshanks wrote to me onMar. 7th, intimating that it was desperate. I had no doubt ofsuccess. Whewell told me that some people accused me of bad faith, inomitting allusion to the _£100_ a year received as Member of the Boardof Longitude, and to the profits of Lectures. I wrote him a note, telling him that I had most certain information of the intention todissolve the Board of Longitude (which was done in less than sixmonths), and that by two years' Lectures I had gained _£45_ (theexpenses being _£200_, receipts _£245_). This letter was sent to thecomplaining people, and no more was said. By the activity ofSheepshanks and the kindness of Dr Davy the business gradually grewinto shape, and on Mar. 21st a Grace passed the Senate for appointinga Syndicate to consider of augmentation. Sheepshanks was one of theSyndicate, and was understood to represent, in some measure, myinterests. The progress of the Syndicate however was by no means astraightforward one. Members of the Senate soon began to remark thatbefore giving anything they ought to know the amount of the Universityrevenue, and another Syndicate was then appointed to enquire andreport upon it. It was more than a year before my Syndicate couldmake their recommendation: however, in fact, I lost nothing by thatdelay, as I was rising in the estimation of the University. TheObservatory house was furnished, partly from Woodhouse's sale, andpartly from new furniture. My mother and sister came to live with methere. On Mar. 15th 1828 I began the Observatory Journal; on Mar. 27thI slept at the Observatory for the first time, and on Apr. 15th I cameto reside there permanently, and gave up my college rooms. " CHAPTER IV. AT CAMBRIDGE OBSERVATORY. FROM HIS TAKING CHARGE OF THE CAMBRIDGE OBSERVATORY TO HIS RESIDENCE AT GREENWICH OBSERVATORY AS ASTRONOMER ROYAL. FROM MARCH 15TH 1828 TO JAN. 1ST 1836. 1828 "I attended a meeting of the Board of Longitude on Apr. 3rd. Andagain on June 4th; this was the last meeting: Sheepshanks hadpreviously given me private information of the certainty of itsdissolution. --On Apr. 4th I visited Mr Herschel at Slough, where oneevening I saw Saturn with his 20-foot telescope, the best view of itthat I have ever had. --In June I attended the Greenwich ObservatoryVisitation. --Before my election (as Plumian Professor) there arevarious schemes on my quires for computation of transit corrections, &c. After Apr. 15th there are corrections for deficient wires, inequality of pivots, &c. And I began a book of proposed regulationsfor observations. In this are plans for groups of stars for R. A. (theTransit Instrument being the only one finished): order of preferenceof classes of observations: no reductions to be made after dinner, oron Sunday: no loose papers: observations to be stopped if reductionsare two months in arrear: stars selected for parallax. --The reductionof transits begins on Apr. 15th. On May 15th Mr Pond sent me somemoon-transits to aid in determining my longitude. --Dr Young, in aletter to me of May 7th, enquires whether I will accept a freeadmission to the Royal Society, which I declined. On May 9th I waselected to the Astronomical Society. --Towards the end of the year Iobserved Encke's Comet: and determined the latitude of the Observatorywith Sheepshanks's repeating circle. --On my papers I find a sketch ofan Article on the Figure of the Earth for the EncyclopaediaMetropolitana. "As early as Feb. 23rd I had been in correspondence with T. Jones, theinstrument-maker, about pendulums for a repetition of the DolcoathExperiments. Invitations had been received, and everything wasarranged with Whewell. Sheepshanks, my brother, and Mr Jackson ofIpswich (Caius Coll. ) were to go, and we were subsequently joined bySedgwick, and Lodge (Magdalene Coll. ). On July 3rd Sheepshanks and Istarted by Salisbury, taking Sherborne on our way to look at thechurch, which had alarmed the people by signs of a crack, and arrivedat Camborne on July 8th. On the 14th we set up the pendulums, and atonce commenced observations, our plan being, to have no intermissionin the pendulum observations, so that as soon as the arc became toosmall a fresh series was started. On July 29th we raised theinstruments, and Sheepshanks, who managed much of the upperoperations, both astronomical and of pendulums, mounted the pendulumstogether in his observatory. We went on with our calculations, and onAugust 8th, on returning from a visit to John Williams at Barncoose, we heard that there was a 'run' in Dolcoath, that is a sinking of thewhole mass of rock where it had been set free by the mine excavations:probably only a few inches, but enough to break the rock much and tostop the pumps. On Aug. 10th the calculations of our observationsshewed that there was something wrong, and on the 13th I perceived ananomaly in the form of the knife edge of one pendulum, and of itsagate planes, and suggested cautions for repeating the observations. We determined at once to repeat them: and as the water was rising inthe mine there was no time to be lost. We again sent the instrumentsdown, and made observations on the 16th, 17th and 18th. On the 19th Isent the instruments up, for the water was near our station, andSedgwick, Whewell, and I went on a geological expedition to theLizard. On our return we met Sheepshanks and the others, and found theresults of the last observations unsatisfactory. The results ofcomparing the pendulums were discordant, and the knife edge of thefaulty pendulum had very sensibly altered. We now gave upobservations, with the feeling that our time had been totally lost, mainly through the fault of the maker of the pendulum (T. Jones). Onthe 28th we made an expedition to Penzance and other places, andarrived at Cambridge on the 17th of September. "In the course of the work at Dolcoath we made various expeditions asopportunity offered. Thus we walked to Carn Brea and witnessed thewrestling, the common game of the country. On another occasionSedgwick, Whewell, and I had a capital geological expedition toTrewavas Head to examine granite veins. We visited at Pendarves andTrevince, and made the expedition to the Lizard already referred to, and saw many of the sights in the neighbourhood. After visitingPenzance on the conclusion of our work we saw Cape Cornwall (whereWhewell overturned me in a gig), and returned homewards by way ofTruro, Plymouth (where we saw the watering-place and breakwater: alsothe Dockyard, and descended in one of the working diving-bells), Exeter, Salisbury, and Portsmouth. In returning from Camborne in 1826I lost the principal of our papers. It was an odd thing that, in goingthrough Exeter on our way to Camborne in 1828, I found them completeat Exeter, identified to the custodian by the dropping out of a letterwith my address. "On my return to Cambridge I was immediately immersed in the work ofthe Observatory. The only instrument then mounted at the Observatorywas the Transit. I had no Assistant whatever. --A Mr Galbraith ofEdinburgh had questioned something in one of my Papers about theFigure of the Earth. I drew up a rather formal answer to it: Whewellsaw my draft and drew up a much more pithy one, which I adopted andsent to the Philosophical Magazine. --For comparing our clocks at theupper and lower stations of Dolcoath we had borrowed from the RoyalObservatory, Greenwich, six good pocket chronometers: they were stillin the care of Mr Sheepshanks. I arranged with him that they should besent backwards and forwards a few times for determining the longitudeof Cambridge Observatory. This was done on Oct. 21st, 22nd, 23rd: theresult was 23°54, and this has been used to the present time(1853). It evinced an error in the Trigonometrical Survey, the originof which was found, I think, afterwards (Dr Pearson in a letter ofDec. 17th spoke of the mistake of a may-pole for a signal-staff). Idrew up a Paper on this, and gave it to the Cambridge PhilosophicalSociety on Nov. 24th. (My only academical Paper this year. )--I hadseveral letters from Dr Young, partly supplying me with calculationsthat I wanted, partly on reform or extension of the Nautical Almanac(which Dr Young resisted as much as possible). He considered me veryunfairly treated in the dissolution of the Board of Longitude:Professor Lax wished me to join in some effort for its restoration, but I declined. "As my reduction of observations was kept quite close, I now began tothink of printing. In regard to the form I determined to adopt a plantotally different from that of any other observations which I hadseen. The results were to be the important things: I was desirous ofsuppressing the separate wires of transits. But upon consultingHerschel and other persons they would not agree to it, and I assentedto keeping them. I applied to the Press Syndicate to print the work, and on Nov. 10th at the request of T. Musgrave (afterwards Archbishopof York) I sent a specimen of my MS. : on Nov. 11th they granted 250copies, and the printing soon commenced. " 1829 "During a winter holiday at Playford I wrote out some investigationsabout the orbits of comets, and on Jan. 23rd 1829 I returned toCambridge. The Smith's Prize Examination soon followed, in which I seta Paper of questions as usual. On Feb. 18th I made notes onLiesganig's geodetic work at the British Museum. "I was naturally anxious now about the settlement of my salary and ofthe Observatory establishment. I do not know when the Syndicate madetheir Report, but it must have been in the last term of 1828. Itrecommended that the salary should be annually made up (by Grace) to_£500_: that an Assistant should be appointed with the assent of theVice-Chancellor and dismissable by the Plumian Professor: and that aVisiting Syndicate should be appointed, partly official and partly ofpersons to be named every year by Grace. The Grace for adopting thisReport was to be offered to the Senate on Feb. 27th. The passing ofthe Grace was exposed to two considerable perils. First, I found out(just in time) that a Senior Fellow of Trinity (G. A. Browne) wasdetermined to oppose the whole, on account of the insignificant clauseregarding dismissal of Assistants, which he regarded as tyrannical. Iat once undertook that that clause should be rejected. Secondly, bythe absurd constitution of the 'Caput' at Cambridge, a single M. A. Hadthe power of stopping any business whatever, and an M. A. Actuallycame to the Senate House with the intention of throwing out all theGraces on various business that day presented to the Senate. Luckilyhe mistook the hour, and came at 11 instead of 10, and found that allwere dispatched. The important parts of the Grace passed without anyopposition: but I mustered some friends who negatived that part whichhad alarmed G. A. Browne, and it was corrected to his satisfaction by anew Grace on Mar. 18th. I was now almost set at rest on one of thegreat objects of my life: but not quite. I did not regard, and Idetermined not to regard, the addition to my salary as absolutelycertain until a payment had been actually made to me: and I carefullyabstained, for the present, from taking any steps based upon it. Ifound for Assistant at the Observatory an old Lieutenant of the RoyalNavy, Mr Baldrey, who came on Mar. 16. "On May 4th I began lectures: there were 32 names. The Lectures wereimproving, especially in the optical part. I do not find note of theday of termination. --I do not know the actual day of publication of myfirst small volume of Cambridge Observations, 1828, and ofcirculation. The date of the preface is Apr. 27th 1829. I have lettersof approval of it from Davies Gilbert, Rigaud, and Lax. The systemwhich I endeavoured to introduce into printed astronomicalobservations was partially introduced into this volume, and wassteadily improved in subsequent volumes. I think that I am justified, by letters and other remarks, in believing that this introduction ofan orderly system of exhibition, not merely of observations but of thesteps for bringing them to a practical result--quite a novelty inastronomical publications--had a markedly good effect on Europeanastronomy in general. --In Feb. And March I have letters from Youngabout the Nautical Almanac: he was unwilling to make any great change, but glad to receive any small assistance. South, who had been keepingup a series of attacks on Young, wrote to me to enquire how I stood inengagements of assistance to Young: I replied that I should assistYoung whenever he asked me, and that I disapproved of South'scourse. --The date of the first visitation of the (Cambridge)Observatory must have been near May 11th: I invited South and Baily tomy house; South and I were very near quarrelling about the treatmentof Young. --In a few days after Dr Young died: I applied to LordMelville for the superintendence of the Nautical Almanac: Mr Crokerreplied that it devolved legally upon the Astronomer Royal, and on May30th Pond wrote to ask my assistance when I could give any. On June6th I was invited to the Greenwich Visitation, to which I believe Iwent on the 10th. "I had long desired to see Switzerland, and I wished now to see someof the Continental Observatories. I was therefore glad to arrange withMr Lodge, of Magdalene College (perhaps 10 years senior to myself), tomake a little tour. Capt. W. H. Smyth and others gave meintroductions. I met Lodge in London, and we started for Calais onJuly 27th 1829. We visited a number of towns in Belgium (at Brussels Isaw the beginning of the Observatory with Quetelet), and passed byCologne, Frankfort, Fribourg, and Basle to Zurich. Thus far we hadtravelled by diligence or posting: we now procured a guide, andtravelled generally on foot. From the 13th to the 31st August wetravelled diligently through the well-known mountainous parts ofSwitzerland and arrived at Geneva on the 31st August. Here I sawM. Gautier, M. Gambard, and the beginning of the Observatory. MrLodge was now compelled to return to Cambridge, and I proceeded aloneby Chambéry to Turin, where I made the acquaintance of M. Plana andsaw the Observatory. I then made a tour through north Italy, lookingover the Observatories at Milan, Padua, Bologna, and Florence. AtLeghorn I took a passage for Marseille in a xebeque, but after sailingfor three days the weather proved very unfavourable, and I landed atSpezia and proceeded by Genoa and the Cornici Road to Marseille. AtMarseille I saw M. Gambart and the Observatory, and passed by Avignon, Lyons, and Nevers to Orléans, where I visited my old hostM. Legarde. Thence by Paris, Beauvais, and Calais to London andCambridge, where I arrived on the 30th October. I had started withmore than _£140_ and returned with _2s. 6d_. The expedition was inmany ways invaluable to me. "On my return I found various letters from scientific men: someapproving of my method for the mass of the Moon: some approving highlyof my printed observations, especially D. Gilbert, who informed methat they had produced good effect (I believe at Greenwich), andHerschel. --On Nov. 13th I gave the Royal Astronomical Society a Paperabout deducing the mass of the Moon from observations of Venus: onNov. 16th a Paper to the Cambridge Philosophical Society on acorrection to the length of a ball-pendulum: and on Dec. 14th a Paperon certain conditions under which perpetual motion is possible. --Theengravings for my Figure of the Earth in the EncyclopaediaMetropolitana were dispatched at the end of the year. Some of thePaper (perhaps much) was written after my return from theContinent. --I began, but never finished, a Paper on the form of theEarth supposed to be projecting at middle latitudes. In this I referto the printed Paper which Nicollet gave me at Paris. I believe thatthe investigations for my Paper in the Encyclopaedia Metropolitana ledme to think the supposition unnecessary. --On Nov. 6th I was electedmember of the Geological Society. "On Nov. 16th 1829 notice was given of a Grace to authorize payment tome of _£157. 9s. 1d. _, in conformity with the regulations adopted onFeb. 27th, and on Nov. 18th the Grace passed the Senate. On Nov. 19ththe Vice-Chancellor wrote me a note enclosing the cheque. On Nov. 23rd(practically the first day on which I could go) I went to London andtravelled to Edensor, where I arrived on the 26th. Here I foundRicharda Smith, proposed to her, and was accepted. I stayed there afew days, and returned to Cambridge. " 1830 "On Jan. 25th 1830 the Smith's Prize Paper was prepared. I was (withmy Assistant, Mr Baldrey) vigorously working the Transit Instrumentand its reductions, and gradually forming a course of proceeding whichhas had a good effect on European Astronomy. And I was preparing formy marriage. "On Mar. 11th I started with my sister to London, and arrived atEdensor on the afternoon of the 14th. On the 17th I started alone forManchester and Liverpool. Through Mr Mason, a cotton-spinner atCalver, near Edensor, I had become acquainted with Mr John Kennedy ofManchester, and I had since 1824 been acquainted with Dr Traill ofLiverpool. Amongst other things, I saw the works of the Manchester andLiverpool Railway, then advancing and exciting great interest, and sawGeorge Stephenson and his son. On Mar. 24th I was married to RichardaSmith by her father in Edensor. We stopped at Edensor till Apr. 1st, and then started in chaises by way of Newark and Kettering (where wewere in danger of being stopped by the snow), and arrived at Cambridgeon Apr. 3rd. "I was now busy in preparing for lectures, especially the part of theoptical lectures which related to the theory of interferences andpolarization. I think it was now that my wife drew some of my lecturepictures, exhibiting interference phenomena. My lectures began onApr. 26th and finished on May 24th. The number of names was 50. Theywere considered an excellent course of lectures. "May 9th is the date of my Preface to the 1829 Observations: all wasthen printed. Apparently I did not go to the Visitation of theGreenwich Observatory this year. --I was at this time pressing Tulley, the optician, about an object-glass for the Mural Circle. --A newedition of my 'Tracts' was wanted, and I prepared to add a Tract onthe Undulatory Theory of Light in its utmost extent. The Syndicate ofthe University Press intimated through Dr Turton that they could notassist me (regarding the book as a second edition). On July 10th Ihave some negociation about it with Deighton the bookseller. --On May18th I have a note from Whewell about a number of crystals ofplagiedral quartz, in which he was to observe the crystallineindication, and I the optical phenomena. --The Report of the Syndicatefor visiting the Observatory is dated June 18th: it is highlylaudatory. --The Proctor (Barnard of King's College) requested me toname the Moderator for the next B. A. Examination: I named Mr Challis. "On June 14th my wife and I went, in company with Professor and MrsHenslow, to London and Oxford; at Oxford we were received inChristchurch College by Dr and Mrs Buckland. My wife and I then wentto Bedford to visit Capt. And Mrs Smyth, and returned to Cambridge onthe 23rd. On July 5th we went on a visit to my mother and uncle atPlayford. While there I took a drive with my uncle into some partsnear the valley of the Gipping, in which I thought that the extent ofthe chalk was inadequately exhibited on Greenough's map, andcommunicated my remarks to Buckland. "I find letters from Dr Robinson and Col. Colby about determininglongitudes of certain observatories by fire signals: I proposedchronometers as preferable. Also from Herschel, approving of my secondvolume of observations: and from F. Baily, disclaiming the originationof the attack on the old Nautical Almanac (with which I suppose I hadreproached him). On July 30th I received a summons from South to acommittee for improving the Nautical Almanac; and subsequently aletter from Baily about Schumacher's taking offence at a passage ofmine in the Cambridge Observations, on the comparative merits ofEphemerides, which I afterwards explained to his satisfaction. "On Aug. 24th my wife and I started for Edensor, and after a shortstay there proceeded by Manchester to Cumberland, where we made manyexcursions. We returned by Edensor, and reached Cambridge on Oct. 6th, bringing my wife's sister Susanna on a visit. My mother haddetermined, as soon as my intention of marriage was known to her, toquit the house, although always (even to her death) entertaining themost friendly feelings and fondness for my wife. It was also judgedbest by us all that my sister should not reside with us as a settledinhabitant of the house. They fixed themselves therefore at Playfordin the farm-house of the Luck's Farm, then in the occupation of myuncle Arthur Biddell. On Oct. 21st I have a letter from my sistersaying that they were comfortably settled there. "In this month of October (principally, I believe) I made some capitalExperiments on Quartz, which were treated mathematically in a Papercommunicated in the next year to the Cambridge PhilosophicalSociety. In some of these my wife assisted me, and also drewpictures. --On Nov. 15th the Grace for paying me _£198. 13s. 8d. _ tomake my income up to _£500_ passed the Senate. --I made three journeysto London to attend committees, one a committee on the NauticalAlmanac, and one a Royal Society Committee about two southernobservatories. --On Dec. 31st I have a letter from Maclear (medicalpractitioner and astronomer at Biggleswade) about occultations. --Inthis December I had a quartz object-glass by Cauchaix mounted byDollond, and presented it to the Observatory. --In this Decemberoccurred the alarm from agrarian fires. There was a very large fire atCoton, about a mile from the Observatory. This created the mostextraordinary panic that I ever saw. I do not think it is possible, without having witnessed it, to conceive the state of men's minds. Thegownsmen were all armed with bludgeons, and put under a rudediscipline for a few days. " 1831 "On Jan. 4th I went with my wife, first to Miss Sheepshanks in London, at 30, Woburn Place, and next to the house of my wife's old friend, the Rev. John Courtney, at Sanderstead, near Croydon. I came to Londonon one day to attend a meeting of the new Board of Visitors of theGreenwich Observatory. Formerly the Board of Visitors consisted of theCouncil of the Royal Society with persons invited by them (in whichcapacity I had often attended). But a reforming party, of whichSouth, Babbage, Baily and Beaufort were prominent members, had inducedthe Admiralty to constitute a new Board, of which the PlumianProfessor was a member. Mr Pond, the Astronomer Royal, was in a ratherfeeble state, and South seemed determined to bear him down:Sheepshanks and I did our best to support him. (I have various lettersfrom Sheepshanks to this purpose. )--On Jan. 22nd we returned toCambridge, and I set an Examination Paper for Smith's Prizes asusual. --On Jan. 30th I have a letter from Herschel about improvingthe arrangement of Pond's Observations. I believe that much of thiszeal arose from the example of the Cambridge Observations. "On Feb. 21st my Paper 'On the nature of the light in the two rays ofQuartz' was communicated to the Philosophical Society: a capital pieceof deductive optics. On Mar. 2nd I went to London, I suppose toattend the Board of Visitors (which met frequently, for the proposedreform of Pond's Observations, &c. ). As I returned on the outside ofthe coach there occurred to me a very remarkable deduction from myideas about the rays of Quartz, which I soon tried with success, andit is printed as an Appendix to the Paper above mentioned. On Mar. 6thmy son George Richard was born. " Miscellaneous matters in the first half of this year are as follows: "Faraday sends me a piece of glass for Amici (he had sent me a piecebefore). --On Apr. 9th I dispatched the Preface of my 1830Observations: this implies that all was printed. --On Apr. 18th I beganmy Lectures and finished on May 24th. There were 49 names. A very goodseries of lectures. --I think it was immediately after this, at theVisitation of the Cambridge Observatory, that F. Baily and Lieut. Stratford were present, and that Sheepshanks went to Tharfield on theRoyston Downs to fire powder signals to be seen at Biggleswade (byMaclear) and at Bedford (by Capt. Smyth) as well as by us atCambridge. --On May 14th I received _£100_ for my article on the Figureof the Earth from Baldwin the publisher of the EncyclopaediaMetropolitana. --I attended the Greenwich Visitation on June 3rd. --OnJune 30th the Observatory Syndicate made their report: satisfactory. "On July 6th 1831 I started with my wife and infant son for Edensor, and went on alone to Liverpool. I left for Dublin on the day on whichthe loss of the 'Rothsay Castle' was telegraphed, and had a badvoyage, which made me ill during my whole absence. After a little stayin Dublin I went to Armagh to visit Dr Robinson, and thence toColeraine and the Giant's Causeway, returning by Belfast and Dublin toEdensor. We returned to Cambridge on Sept. 9th. "Up to this time the Observatory was furnished with only one largeinstrument, namely the 10-foot Transit. On Feb. 24th of this year Ihad received from Thomas Jones (62, Charing Cross) a sketch of thestone pier for mounting the Equatoreal which he was commissioned tomake: and the pier was prepared in the spring or summer. On Sept. 20thpart of the instrument was sent to the Observatory; other partsfollowed, and Jones himself came to mount it. On Sept. 16th I receivedSimms's assurance that he was hastening the Mural Circle. --In thisautumn I seriously took up the recalculation of my Long Inequality ofVenus and the Earth, and worked through it independently; thuscorrecting two errors. On Nov. 10th I went to Slough, to put my Paperin the hands of Mr Herschel for communication to the RoyalSociety. The Paper was read on Nov. 24th. --This was the year of thefirst Meeting of the British Association at York. The next year'smeeting was to be at Oxford, and on Oct. 17th I received from theRev. W. Vernon Harcourt an invitation to supply a Report on Astronomy, which I undertook: it employed me much of the winter, and thesucceeding spring and summer. --The second edition of my Tracts wasready in October. It contained, besides what was in the first edition, the Planetary Theory, and the Undulatory Theory of Light. The Profitwas _£80_. --On Nov. 14th I presented to the Cambridge PhilosophicalSociety a Paper 'On a remarkable modification of Newton's Rings': apretty good Paper. --In November the Copley Medal was awarded to me bythe Royal Society for my advances in Optics. --Amongst miscellaneousmatters I was engaged in correspondence with Col. Colby andCapt. Portlock about the Irish Triangulation and its calculation. Alsowith the Admiralty on the form of publication of the Greenwich andCape Observations. " 1832 "In January my Examination Paper for Smith's Prizes was prepared asusual. --Two matters (in addition to the daily routine of Observatorywork) occupied me at the beginning of this year. One was thetranslation of Encke's Paper in successive numbers of theAstronomische Nachrichten concerning Encke's Comet; the UniversityPress printed this gratuitously, and I distributed copies, partly bythe aid of Capt. Beaufort. --The other was the Report on Astronomy forthe British Association, which required much labour. My reading forit was principally in the University Library (possibly some inLondon), but I borrowed some books from F. Baily, and I wrote toCapt. Beaufort about the possible repetition of Lacaille's MeridianArc at the Cape of Good Hope. The Report appears to have been finishedon May 2nd. --At this time the Reform Bill was under discussion, andone letter written by me (probably at Sheepshanks's request) addressedI think to Mr Drummond, Lord Althorp's secretary, was read in theHouse of Commons. "Optics were not neglected. I have some correspondence with Brewsterand Faraday. On Mar. 5th I gave the Cambridge Philosophical Society aPaper 'On a new Analyzer, ' and on Mar. 19th one 'On Newton's Ringsbetween two substances of different refractive powers, ' both Paperssatisfactory to myself. --On the death of Mr F. Fallows, astronomer atthe Cape of Good Hope Observatory, the Admiralty appointed MrHenderson, an Edinburgh lawyer, who had done some little things inastronomical calculation. On Jan. 10th I discussed with himobservations to be made, and drew up his Official Instructions whichwere sent on Jan. 10th. --On Feb. 16th Sir James South writes thatEncke's Comet is seen: also that with his 12-inch achromatic, purchased at Paris, and which he was preparing to mount equatoreally, he had seen the disk of Aldebaran apparently bisected by the Moon'slimb. --Capt. Beaufort and D. Gilbert write in March about instructionsto Dunlop, the astronomer at Paramatta. I sent a draft toCapt. Beaufort on Apr. 27th. "The Preface to my 1831 Observations is dated Mar. 20th. Thedistribution of the book would be a few weeks later. --On May 7th Ibegan my Lectures: 51 names: I finished on May 29th. --The mounting ofthe Equatoreal was finished some time before the Syndicate Visitationat the end of May, but Jones's charge appeared to be exorbitant: Ibelieve it was paid at last, but it was considered unfair. --On June2nd I went to London: I presume to the Greenwich Visitation. --I wentto Oxford to the meeting of the British Association (lodging I thinkwith Prof. Rigaud at the Observatory) on June 16th, and read part ofmy Report on Astronomy in the Theatre. "On June 26th I started with my wife for the Highlands ofScotland. After a short stay at Edensor, we went by Carlisle toGlasgow, and through the Lake District to Inverness. Thence byAuchnanault to Balmacarra, where we were received by MrLillingstone. After an expedition in Skye, we returned to Balmacarra, and passed on to Invermoriston, where we were received by Grant ofGlenmoriston. We then went to Fort William and Oban, and crossed overto Mull, where we were received by Maclean of Loch Buy. We returned toOban and on to Edinburgh, where we made a short stay. Then to Melrose, where we were received by Sir D. Brewster, and by Edensor toCambridge, where we arrived on Sept. 17th. "I received (at Edinburgh I believe) a letter from Arago, writing forthe plans of our observing-room shutters. --Mr Vernon Harcourt wrotedeprecating the tone of my Report on Astronomy as related to EnglishAstronomers, but I refused to alter a word. --Sheepshanks wrote inSeptember in great anxiety about the Cambridge Circle, for which hethought the pier ought to be raised: I would have no such thing, andarranged it much more conveniently by means of a pit. On Oct. 9thSimms says that he will come with the circle immediately, and Jones onSept. 29th says that he will make some alteration in the equatoreal:thus there was at last a prospect of furnishing the Observatoryproperly. --On Oct. 9th, I have Encke's thanks for the translation ofthe Comet Paper. --One of the desiderata which I had pointed out in myReport on Astronomy was the determination of the mass of Jupiter byelongations of the 4th satellite: and as the Equatoreal of theCambridge Observatory was on the point of coming into use, Idetermined to employ it for this purpose. It was necessary for thereduction of the observations that I should prepare Tables of themotion of Jupiter's 4th Satellite in a form applicable to computationsof differences of right-ascension. The date of my Tables is Oct. 3rd, 1832. --In October the Observatory Syndicate made their Report: quitesatisfactory. "On Oct. 20th Sheepshanks wrote asking my assistance in the PennyCyclopaedia: I did afterwards write 'Gravitation' and 'Greenwich. '--Capt. Beaufort wrote in November to ask my opinion on thePreface to an edition of Groombridge's Catalogue which had beenprepared by H. Taylor: Sheepshanks also wrote; he had objected toit. This was the beginning of an affair which afterwards gave me greatlabour. --Vernon Harcourt writes, much offended at some terms which Ihad used in reference to an office in the British Association. "The Equatoreal mounting which Troughton and Simms had been preparingfor Sir James South's large telescope had not entirely succeeded. Ihave various letters at this time from Sheepshanks and Simms, relatingto the disposition which Sir James South shewed to resist every claimtill compelled by law to pay it. --A general election of Members ofParliament was now coming on: Mr Lubbock was candidate for theUniversity. On Nov. 27th I had a letter from Sedgwick requesting me towrite a letter in the newspapers in favour of Lubbock; which I did. OnDec. 7th I have notice of the County voting at Newmarket on Dec. 18thand 19th: I walked there to vote for Townley; he lost the election bytwo or three votes in several thousands. "The Mural Circle was now nearly ready in all respects, and it wasknown that another Assistant would be required. Mr Richardson (one ofthe Assistants of Greenwich Observatory) and Mr Simms recommended tome Mr Glaisher, who was soon after appointed, and subsequently becamean Assistant at Greenwich. --On Dec. 24th I have a letter from Bessel(the first I believe). I think that I had written to him about ageneral reduction of the Greenwich Planetary Observations, using hisTabulae Regiomontanae as basis, and that this was his reply approvingof it. " 1833 "On Jan. 4th 1833 my daughter Elizabeth was born. --I prepared anexamination paper for Smith's Prizes as usual. --On Jan. 5th I receivednotice from Simms that he had received payment (_£1050_) for the MuralCircle from the Vice-Chancellor. About this time the Circle wascompletely made serviceable, and I (with Mr Glaisher as Assistant)immediately began its use. A puzzling apparent defect in the circle(exhibiting itself by the discordance of zenith points obtained byreflection observations on opposite sides of the zenith) shewed itselfvery early. On Feb. 4th I have letters about it from Sheepshanks andSimms. --On Jan. 17th I received notice from F. Baily that theAstronomical Society had awarded me their Medal for my long inequalityof Venus and the Earth: on Feb. 7th I went to London, I suppose toreceive the Medal. --I also inspected Sir J. South's telescope, thenbecoming a matter of litigation, and visited Mr Herschel at Slough: onFeb. 12th I wrote to Sir J. South about the support of theinstrument, hoping to remove one of the difficulties in thelitigation; but it produced no effect. --Herschel wrote to me, fromPoisson, that Pontécoulant had verified my Long Inequality. "Mar. 12th is the date of the Preface to my 1832 volume ofObservations: it was of course distributed a few weeks later. --In myReport on Astronomy I had indicated the Mass of Jupiter as a subjectrequiring fresh investigation. During the last winter I had wellemployed the Equatoreal in observing elongations in R. A. Of the 4thSatellite. To make these available it was necessary to work up thetheory carefully, in which I discovered some remarkable errors ofLaplace. Some of these, for verification, I submitted to Mr Lubbock, who entirely agreed with me. The date of my first calculations of theMass of Jupiter is Mar. 1st: and shortly after that I gave an oralaccount of them to the Cambridge Philosophical Society. The date of myPaper for the Astronomical Society is April 12th. The result of myinvestigations (which was subsequently confirmed by Bessel) entirelyremoved the difficulty among Astronomers; and the mass which Iobtained has ever since been received as the true one. "On Apr. 9th my wife's two sisters, Elizabeth and Georgiana Smith, came to stay with me. --On Apr. 22nd I began lectures, and finished onMay 21st: there were 54 names. During the course of the lectures Icommunicated a Paper to the Philosophical Society 'On the calculationof Newton's experiments on Diffraction. '--I went to London on theVisitation of the Greenwich Observatory: the dinner had been muchrestricted, but was now made more open. --It had been arranged that themeeting of the British Association was to be held this year atCambridge. I invited Sir David Brewster and Mr Herschel to lodge atthe Observatory. The meeting lasted from June 24th to 30th. We gaveone dinner, but had a breakfast party every day. I did not enter muchinto the scientific business of the meeting, except that I broughtbefore the Committee the expediency of reducing the GreenwichPlanetary Observations from 1750. They agreed to represent it to theGovernment, and a deputation was appointed (I among them) who werereceived by Lord Althorp on July 25th. On Aug. 3rd Herschel announcedto me that _£500_ was granted. "On Aug. 7th I started with my wife for Edensor. At Leicester we metSedgwick and Whewell: my wife went on to Edensor, and I joinedSedgwick and Whewell in a geological expedition to Mount Sorrel andvarious parts of Charnwood Forest. We were received by Mr Allsop ofWoodlands, who proved an estimable acquaintance. This lasted four orfive days, and we then went on to Edensor. --On Aug. 15th Herschelwrote to me, communicating an offer of the Duke of Northumberland topresent to the Cambridge Observatory an object-glass of about 12inches aperture by Cauchaix. I wrote therefore to the Duke, acceptinggenerally. The Duke wrote to me from Buxton on Aug. 23rd (his letter, such was the wretched arrangement of postage, reaching Bakewell andEdensor on the 25th) and on the 26th I drove before breakfast toBuxton and had an interview with him. On Sept. 1st the Duke wrote, authorizing me to mount the telescope entirely, and he subsequentlyapproved of Cauchaix's terms: there was much correspondence, but onDec. 28th I instructed Cauchaix how to send the telescope. --On ourreturn we paid a visit to Dr Davy, Master of Caius College, atHeacham, and reached Cambridge on Oct. 8th. "Groombridge's Catalogue, of which the editing was formally entrustedto Mr Henry Taylor (son of Taylor the first-assistant of the GreenwichObservatory), had been in some measure referred to Sheepshanks: andhe, in investigating the work, found reason for thinking the wholediscreditable. About May he first wrote to me on his rising quarrelwith H. Taylor, but on Sept. 7th he found things coming to a crisis, and denounced the whole. Capt. Beaufort the Hydrographer (in whoseoffice this matter rested) begged me with Baily to decide upon it. Wedid not at first quite agree upon the terms of investigation &c. , butafter a time all was settled, and on Oct. 4th the Admiralty formallyapplied, and I formally accepted. Little or nothing had been done byMr Baily and myself, when my work was interrupted by illness. "Sheepshanks had thought that something might be done to advance theinterests of myself or the Observatory by the favour of Lord Brougham(then Lord Chancellor), and had urged me to write an article in thePenny Cyclopaedia, in which Lord Brougham took great interest. I chosethe subject 'Gravitation, ' and as I think wrote a good deal of it inthis Autumn: when it was interrupted by my illness. "On Dec. 9th 1833, having at first intended to attend the meeting ofthe Philosophical Society and then having changed my mind, I wasengaged in the evening on the formulae for effects of small errors onthe computation of the Solar Eclipse of 1833. A dizziness in my headcame on. I left off work, became worse, and went to bed, and in thenight was in high fever with a fierce attack of scarlet fever. My wifewas also attacked but very slightly. The first day of quitting mybedroom was Dec. 31st. Somewhere about the time of my illness mywife's sister, Susanna Smith, who was much reduced in the summer, diedof consumption. "Miscellaneous notes in 1833 are as follows: Henderson (at the Cape)could not endure it much longer, and on Oct. 14th Stratford writesthat Maclear had just sailed to take his place: Henderson is candidatefor the Edinburgh Observatory. --Stratford writes on Dec. 2nd that theMadras observations have come to England, the first whose arrangementimitates mine. --On Nov. 3rd Herschel, just going to the Cape, entrusted to me the revisal of some proof sheets, if necessary:however it was never needed. --In November I sat for my portrait to apainter named Purdon (I think): he came to the house and made a goodlikeness. A pencil portrait was taken for a print-seller (Mason) inCambridge: it was begun before my illness and finished after it. --Iapplied through Sheepshanks for a copy of Maskelyne's Observations, tobe used in the Reduction of the Planetary Observations: and onDec. 24th (from my bedroom) I applied through Prof. Rigaud to theDelegates of the Clarendon Press for a copy of Bradley's Observationsfor the same. The latter request was refused. In October I applied tothe Syndics of the University Press for printed forms for theseReductions: the Syndics agreed to grant me 12, 000 copies. " 1834 "On Jan. 11th 1834 I went with my wife to London for the recruiting ofmy strength. We stayed at the house of our friend Miss Sheepshanks, and returned on Feb. 13th. --I drew up a Paper of Questions for Smith'sPrizes, but left the whole trouble of examination and adjudication toProfessor Miller, who at my request acted for me. --While I was inLondon I began to look at the papers relating to Groombridge'sCatalogue: and I believe that it was while in London that I agreedwith Mr Baily on a Report condemnatory of H. Taylor's edition, andsent the Report to the Admiralty. The Admiralty asked for furtheradvice, and on Feb. 28th I replied, undertaking to put the Cataloguein order. On Mar. 17th Capt. Beaufort sent me all the papers. Sometime however elapsed before I could proceed with it. "There was in this spring a furious discussion about the admission ofDissenters into the University: I took the Liberal side. On Apr. 30ththere was a letter of mine in the Cambridge newspaper. --On Apr. 14th Ibegan lectures, and finished on May 20th: there were 87 names. --My'Gravitation' was either finished or so nearly finished that on Jan. 24th I had some conversation with Knight the publisher about printingit. It was printed in the spring, and on Apr. 27th Sheepshanks sent acopy of it to Lord Brougham. I received from Knight _£83. 17s. 1d. _for this Paper. --On May 10th I went to London, I believe to attend oneof the Soirées which the Duke of Sussex gave as President of the RoyalSociety. The Duke invited me to breakfast privately with him the nextmorning. He then spoke to me, on the part of the Government, about mytaking the office of Astronomer Royal. On May 19th I wrote him asemi-official letter, to which reference was made in subsequentcorrespondence on that subject. "On May 12th my son Arthur was born. --In June the ObservatorySyndicate made a satisfied Report. --On June 7th I went to theGreenwich Visitation, and again on June 14th I went to London, Ibelieve for the purpose of trying the mounting of South's telescope, as it had been strengthened by Mr Simms by Sheepshanks'ssuggestions. I was subsequently in correspondence with Sheepshanks onthe subject of the Arbitration on South's telescope, and my givingevidence on it. On July 29th, as I was shortly going away, I wrote hima Report on the Telescope, to be used in case of my absence. Theaward, which was given in December, was entirely in favour ofSimms. --On July 23rd I went out, I think to my brother's marriage atIxworth in Suffolk. --On Aug. 1st I started for Edensor and Cumberland, with my wife, sister, and three children: Georgiana Smith joined us atEdensor. We went by Otley, Harrogate, Ripon, and Stanmoor to Keswick, from whence we made many excursions. On Aug. 11th I went with Whewellto the clouds on Skiddaw, to try hygrometers. Mr Baily called on hisway to the British Association at Edinburgh. On Sept. 10th wetransferred our quarters to Ambleside, and after various excursions wereturned to Edensor by Skipton and Bolton. On Sept. 19th I went toDoncaster and Finningley Park to see Mr Beaumont's Observatory. OnSept. 25th we posted in one day from Edensor to Cambridge. "On Aug. 25th Mr Spring Rice (Lord Monteagle) wrote to me to enquirewhether I would accept the office of Astronomer Royal if it werevacant. I replied (from Keswick) on Aug. 30th, expressing my generalwillingness, stipulating for my freedom of vote, &c. , and referring tomy letter to the Duke of Sussex. On Oct. 8th Lord Auckland, First Lordof the Admiralty, wrote: and on Oct. 10th I provisionally accepted theoffice. On Oct. 30th I wrote to ask for leave to give a course oflectures at Cambridge in case that my successor at Cambridge shouldfind difficulty in doing it in the first year: and to this LordAuckland assented on Oct. 31st. All this arrangement was for a timeupset by the change of Ministry which shortly followed. "Amongst miscellaneous matters, in March I had some correspondencewith the Duke of Northumberland about the Cauchaix Telescope. InAugust I had to announce to him that the flint-lens had been a littleshattered in Cauchaix's shop and required regrinding: finally onDec. 17th I announced its arrival at Cambridge. --In the PlanetaryReductions, I find that I employed one computer (Glaisher) for 34weeks. --In November the Lalande Medal was awarded to me by the FrenchInstitut, and Mr Pentland conveyed it to me in December. --On March14th I gave the Cambridge Philosophical Society a Paper, 'Continuationof researches into the value of Jupiter's Mass. ' On Apr. 14th, 'On theLatitude of Cambridge Observatory. ' On June 13th, 'On the position ofthe Ecliptic, ' and 'On the Solar Eclipse of 1833, ' to the RoyalAstronomical Society. On Nov. 24th, 'On Computing the Diffraction ofan Object Glass, ' to the Cambridge Society. And on Dec. 3rd, 'On theCalculation of Perturbations, ' to the Nautical Almanac: this Paper waswritten at Keswick between Aug. 22nd and 29th. --I also furnished MrSheepshanks with investigations regarding the form of the pivots ofthe Cape Circle. " 1835 "On Jan. 9th 1835 I was elected correspondent of the French Academy;and on Jan. 26th Mr Pentland sent me _£12. 6s. _, the balance of theproceeds of the Lalande Medal Fund. --I prepared my Paper for Smith'sPrizes, and joined in the Examination as usual. "There had been a very sudden change of Administration, and SirR. Peel was now Prime Minister as First Lord of the Treasury, and LordLyndhurst was Lord Chancellor. On Jan. 19th I wrote to LordLyndhurst, asking him for a Suffolk living for my brother William, which he declined to give, though he remembered my application someyears later. Whether my application led to the favour which I shortlyreceived from the Government, I do not know. But, in dining with theDuke of Sussex in the last year, I had been introduced to Sir R. Peel, and he had conversed with me a long time, and appeared to have heardfavourably of me. On Feb. 17th he wrote to me an autograph letteroffering a pension of _£300_ per annum, with no terms of any kind, andallowing it to be settled if I should think fit on my wife. I wroteon Feb. 18th accepting it for my wife. In a few days the matter wentthrough the formal steps, and Mr Whewell and Mr Sheepshanks werenominated trustees for my wife. The subject came before Parliament, bythe Whig Party vindicating their own propriety in having offered methe office of Astronomer Royal in the preceding year; and SpringRice's letter then written to me was published in the Times, &c. " * * * * * The correspondence relating to the pension above-mentioned is givenbelow, and appears to be of interest, both as conveying in veryfelicitous terms the opinion of a very eminent statesman on thegeneral subject of such pensions, and as a most convincing proof ofthe lofty position in Science which the subject of this Memoir hadthen attained. WHITEHALL GARDENS, _Feb. 17 1835_. SIR, You probably are aware that in a Resolution voted by the House ofCommons in the last Session of Parliament, an opinion was expressed, that Pensions on the Civil List, ought not thereafter to be granted bythe Crown excepting for the satisfaction of certain public claims, among which those resting on Scientific or Literary Eminence wereespecially mentioned. I trust that no such Resolution would have been necessary to induce meas Minister of the Crown fully to recognize the justice of suchclaims, but I refer to the Resolution, as removing every impediment toa Communication of the nature of that which I am about to make to you. In acting upon the Principle of the Resolution in so far as the Claimsof Science are concerned, my _first_ address is made to you, and madedirectly, and without previous communication with any other person, because it is dictated exclusively by public considerations, andbecause there can be no advantage in or any motive for indirectcommunication. I consider you to have the first claim on the Royal Favour whichEminence in those high Pursuits to which your life is devoted, cangive, and I fear that the Emoluments attached to your appointment inthe University of Cambridge are hardly sufficient to relieve you fromanxiety as to the Future on account of those in whose welfare you aredeeply interested. The state of the Civil List would enable me to advise the King togrant a pension of three hundred pounds per annum, and if the offer beacceptable to you the Pension shall be granted either to Mrs Airy oryourself as you may prefer. I beg you distinctly to understand that your acquiescence in thisProposal, will impose upon you no obligation personal or political inthe slightest degree. I make it solely upon public grounds, and I askyou, by the acceptance of it, to permit the King to give some slightencouragement to Science, by proving to those who may be disposed tofollow your bright Example, that Devotion to the highest Branches ofMathematical and Astronomical Knowledge shall not necessarily involvethem in constant solicitude as to the future condition of those, forwhom the application of the same Talents to more lucrative Pursuitswould have ensured an ample Provision. I have the honor to be, Sir, With true Respect and Esteem, Your faithful Servant, ROBERT PEEL. _Mr Professor Airy, &c. , &c. , Cambridge_. OBSERVATORY, CAMBRIDGE, _1835, Feb. 18_. SIR, I have the honor to acknowledge your letter of the 17th acquainting mewith your intention of advising the King to grant a pension of _£300_per annum from the Civil List to me or Mrs Airy. I trust you will believe that I am sensible of the flattering terms inwhich this offer is made, and deeply grateful for the consideratemanner in which the principal arrangement is left to my choice, aswell as for the freedom from engagement in which your offer leavesme. I beg to state that I most willingly accept the offer. I shouldprefer that the pension be settled on Mrs Airy (by which I understandthat in case of her surviving me the pension would be continued to herduring her life, or in the contrary event would cease with her life). I wish that I may have the good fortune to prove to the world that Ido not accept this offer without an implied engagement on my part. Ibeg leave again to thank you for your attention, and to assure youthat the form in which it is conveyed makes it doubly acceptable. With sincere respect I have the honor to be, Sir, Your very faithful Servant, G. B. AIRY. _The Right Hon. Sir Robert Peel, Bart. , First Lord of the Treasury, &c. , &c. _ WHITEHALL, _Feb. 19th 1835_. SIR, I will give immediate directions for the preparation of the Warrantsettling the Pension on Mrs Airy--the effect of which will be, as yousuppose, to grant the Pension to her for her life. I assure you Inever gave an official order, which was accompanied with moresatisfaction to myself than this. I have the honor to be, Sir. Your faithful Servant, ROBERT PEEL. _Mr Professor Airy, &c. , &c. , Cambridge_. * * * * * "On March 18th 1835 I started (meeting Sheepshanks at Kingstown) forIreland. We visited Dublin Observatory, and then went direct toMarkree near Sligo, to see Mr Cooper's telescope (our principalobject). We passed on our return by Enniskillen and Ballyjamesduff, where my former pupil P. Morton was living, and returned onApr. 3rd. --On Apr. 20th I was elected to the Royal Society, Edinburgh. --Apr. 22nd my wife wrote me from Edensor that her sisterFlorence was very ill: she died shortly after. --On May 4th I beganlectures and finished on May 29th: there were 58 names. --My formerpupil Guest asks my interest for the Recordership of Birmingham. --InJune was circulated the Syndicate Report on the Observatory. --The dateof the Preface to the 1834 Observations is June 16th. "The Ministry had been again changed in the spring, and the Whigs wereagain in power. On June 11th Lord Auckland, who was again First Lordof the Admiralty (as last year), again wrote to me to offer me theoffice of Astronomer Royal, or to request my suggestions on thefilling up of the office. On June 15th I wrote my first reply, and onJune 17th wrote to accept it. On June 18th Lord Auckland acknowledges, and on June 22nd the King approved. Lord Auckland appointed to see meon Friday, June 23rd, but I was unwell. I had various correspondencewith Lord Auckland, principally about buildings, and had anappointment with him for August 13th. As Lord Auckland was justquitting office, to go to India, I was introduced to Mr Charles Wood, the Secretary of the Admiralty, with whom principally the subsequentbusiness was transacted. At this meeting Lord Auckland and Mr Woodexpressed their feeling, that the Observatory had fallen into such astate of disrepute that the whole establishment ought to be clearedout. I represented that I could make it efficient with a good FirstAssistant; and the other Assistants were kept. But the establishmentwas in a queer state. The Royal Warrant under the Sign Manual was senton August 11th. It was understood that my occupation of office wouldcommence on October 1st, but repairs and alterations of buildingswould make it impossible for me to reside at Greenwich before the endof the year. On Oct. 1st I went to the Observatory, and enteredformally upon the office (though not residing for some time). Oct 7this the date of my Official Instructions. "I had made it a condition of accepting the office that the then FirstAssistant should be removed, and accordingly I had the charge ofseeking another. I determined to have a man who had taken arespectable Cambridge degree. I made enquiry first of Mr Bowstead(brother to the bishop) and Mr Steventon: at length, consulting MrHopkins (a well-known private tutor at Cambridge), he recommended tome Mr Robert Main, of Queens' College, with whom I corresponded in themonth (principally) of August, and whom on August 30th I nominated tothe Admiralty. On Oct. 21st F. W. Simms, one of the Assistants (whoapparently had hoped for the office of First Assistant, for which hewas quite incompetent) resigned; and on Dec. 4th I appointed in hisplace Mr James Glaisher, who had been at Cambridge from the beginningof 1833, and on Dec. 10th the Admiralty approved. "During this quarter of a year I was residing at CambridgeObservatory, visiting Greenwich once a week (at least for some time), the immediate superintendence of the Observatory being placed with MrMain. I was however engaged in reforming the system of the GreenwichObservatory, and prepared and printed 30 skeleton forms for reductionsof observations and other business. On Dec. 14th I resigned myProfessorship to the Vice-Chancellor. But I continued the reduction ofthe observations, so that not a single figure was left to mysuccessor: the last observations were those of Halley's Comet. ThePreface to my 1835 Cambridge Observations is dated Aug. 22nd, 1836. "In regard to the Northumberland Telescope, I had for some time beenspeculating on plans of mounting and enclosing the instrument, and hadcorresponded with Simms, A. Biddell, Cubitt, and others on thesubject. On Apr. 24th Tulley the younger was endeavouring to adjustthe object-glass. On May 31st I plainly asked the Duke ofNorthumberland whether he would defray the expense of the mounting andbuilding. On June 4th he assented, and money was placed at a banker'sto my order. I then proceeded in earnest: in the autumn the buildingwas erected, and the dome was covered before the depth of winter. Icontinued in 1836 to superintend the mounting of the instrument. "In regard to the Planetary Reductions: to July 11th J. Glaisher hadbeen employed 27 weeks, and from July 11th to Jan. 16th, 1836, 25weeks. Mr Spring Rice, when Chancellor of the Exchequer, had promisedmoney, but no official minute had been made, and no money had beengranted. On Aug. 21st I applied to Mr Baring (Secretary of theTreasury). After another letter he answered on Oct. 15th that hefound no official minute. After writing to Vernon Harcourt and toSpring Rice, the matter was arranged: my outlay was refunded, andanother sum granted. --In regard to Groombridge's Observations, I findthat on Dec. 16th certain trial reductions had been made under mydirection by J. Glaisher. --I had attempted some optical experiments inthe summer, especially on the polarization of sky-light; but had beentoo busy with the Observatory to continue them. "In August my wife was in a critical state of health. --In December Ireceived information regarding merchant ships' chronometers, for whichI had applied to Mr Charles Parker of Liverpool. --On Dec. 8th MrSpring Rice and Lord John Russell offered me knighthood, but Ideclined it. --On July 23rd I went into Suffolk with my wife's sistersElizabeth and Georgiana, and returned on August 3rd: this was all theholiday that I got in this year. --On the 14th of August I saw MrTaylor, the Admiralty Civil Architect in London, and the extension ofbuildings at Greenwich Observatory was arranged. --I made variousjourneys to Greenwich, and on Dec. 17th, having sent off ourfurniture, we all quitted the Cambridge Observatory, and stayed forsome days at the house of Miss Sheepshanks. "Thus ended a busy and anxious year. " * * * * * With reference to the offer of knighthood above-mentioned, Airy'sreply is characteristic, and the short correspondence relating to itis therefore inserted. --The offer itself is an additional proof of thehigh estimation in which he stood at this time. DOWNING STREET, _Dec. 8th 1835_. MY DEAR SIR, I have been in communication with my colleague Lord John Russell whichhas made me feel rather anxious to have the pleasure of seeing you, but on second thoughts it has occurred to me that the subject of mycommunication would render it more satisfactory to you to receive aletter than to pay a visit. In testimony of the respect which is felt for your character andacquirements, there would be every disposition to recommend you to HisMajesty to receive the distinction of Knighthood. I am quite awarethat to you individually this may be a matter of small concern, but tothe scientific world in general it will not be indifferent, and toforeign countries it will mark the consideration felt for youpersonally as well as for the position which you occupy among yourlearned contemporaries. From a knowledge of the respect and esteem which I feel for you LordJohn Russell has wished that the communication should be made throughme rather than through any person who had not the pleasure of youracquaintance. Pray let me hear from you and believe me my dear Sir, with complimentsto Mrs Airy, Very truly yours, T. SPRING RICE. P. S. --It may be right to add that when a title of honor is conferredon grounds like those which apply to your case, no fees or charges ofany kind would be payable. OBSERVATORY, CAMBRIDGE, _1835, Dec. 10th_. MY DEAR SIR, I beg to acknowledge your letter of the 8th, which I have received atthis place, conveying to me an intimation of the wish of His Majesty'sMinisters to recommend me to the King for the honor of Knighthood. I beg to assure you that I am most sensible to the liberality which Ihave experienced from the Government in other as well as in pecuniarymatters, and that I am very highly gratified by the consideration(undeserved by me, I fear) which they have displayed in the presentinstance. And if I now request permission to decline the honor offeredto me, I trust I may make it fully understood that it is not because Ivalue it lightly or because I am not anxious to receive honors fromsuch a source. The unalterable custom of this country has attached a certain degreeof light consideration to titles of honor which are not supported byconsiderable fortune; or at least, it calls for the display of such anestablishment as may not be conveniently supported by even acomfortable income. The provision attached to my official situation, and the liberality of the King towards one of the members of myfamily, have placed me in a position of great comfort. Thesecircumstances however have bound me to consider myself as the devotedservant of the country, and to debar myself from efforts to increasemy fortune which might otherwise have been open to me. I do not lookforward therefore to any material increase of income, and that which Ienjoy at present is hardly sufficient, in my opinion, to supportrespectably the honor which you and Lord John Russell have proposed toconfer upon me. For this reason only I beg leave most respectfully todecline the honor of Knighthood at the present time. I have only to add that my services will always be at the command ofthe Government in any scientific subject in which I can be of thesmallest use. I am, my dear Sir, Your very faithful Servant, G. B. AIRY. _The Right Honorable T. Spring Rice_. * * * * * "In brief revision of the years from 1827 to 1835 I may confine myselfto the two principal subjects--my Professorial Lectures, and myConduct of the Cambridge Observatory. "The Lectures as begun in 1827 included ordinary Mechanics, ordinaryHydrostatics and Pneumatics (I think that I did not touch, or touchedvery lightly, on the subjects connected with the Hydraulic Ram), andordinary Optics (with a very few words on Polarization andDepolarization). In 1828 the two first were generally improved, andfor the third (Optics) I introduced a few words on CircularPolarization. I believe that it was in 1829 that I made an additionto the Syllabus with a small engraving, shewing the interference oflight in the best practical experiment (that of the flat prism); and Iwent thoroughly into the main points of the Undulatory Theory, interference, diffraction, &c. In 1830 I believe I went (in additionto what is mentioned above) into Polarization and Depolarization ofall kinds. My best lecture diagrams were drawn and painted by mywife. The Lectures were universally pronounced to be valuable. Thesubjects underwent no material change in 1831, 2, 3, 4, 5; and Ibelieve it was a matter of sincere regret to many persons that myremoval to Greenwich terminated the series. Each lecture nominallyoccupied an hour. But I always encouraged students to stop and talkwith me; and this supplement was usually considered a valuable part ofthe lecture. Practically the lecture, on most days, occupied twohours. I enjoyed the Lectures much: yet I felt that the labour (inaddition to other work) made an impression on my strength, and Ibecame at length desirous of terminating them. "The Observatory, when I took charge of it, had only oneinstrument--the Transit-Instrument The principles however which I laiddown for my own direction were adapted to the expected completeequipment, Planets (totally neglected at Greenwich) were to beobserved. Observations were to be reduced completely, and thereductions were to be exhibited in an orderly way: this was a noveltyin Astronomy. I considered it so important that I actually proposedto omit in my publication the original observations, but was dissuadedby Herschel and others. I sometimes suspended, observations for ashort time, in order to obtain leisure for; the reductions. I had atfirst no intention of correcting the places of the fundamental starsas settled at Greenwich. But I found myself compelled to do so, because they were not sufficiently accurate; and then I took thecourse of observing and reducing as an independent observer, withoutreference to any other observatory. I introduced the principle of notcorrecting instrumental errors, but measuring them and applyingnumerical corrections. I determined my longitude by chronometers, andmy latitude by a repeating circle borrowed from Mr Sheepshanks, whichI used so well that the result; was only half a second in error. Theform of my reductions in the published volume for 1828 is ratherirregular, but the matter is good: it soon attracted attention. In1829 the process was much the same: I had an assistant, Mr Baldrey. In 1830 still the same, with the additions:--that I formally gave thecorrections of relative right-ascension of fundamental stars (withoutalteration of equinox, which I had not the means of obtaining) to beused in the year 1831; and that I reduced completely the observedoccultations (with a small error, subsequently corrected). In 1831 thesystem of correction of broken transits was improved: the errors ofassumed R. A. Of Fundamental Stars were exhibited: Mean Solar Time wasobtained from Sidereal Time by time of Transit of [Symbol: Aries](computed by myself): the method of computing occultations wasimproved. In 1832 the small Equatoreal was erected, and was soonemployed in observations of the elongation of the 4th Satellite ofJupiter for determining the mass of Jupiter. The Mural Circle waserected at the end of the year, but not used. The calculation ofR. A. Of Fundamental Stars was made homogeneously with the others:separate results of all were included in ledgers: a star-catalogue wasformed: all as to the present time (1871). With the Equatoreal thedifference of N. P. D. Of Mars and stars was observed. "With the beginning of 1833 the Mural Circle was established at work, a second assistant (Mr Glaisher) was appointed, and the Observatorymight be considered complete. I made experiments on the graduations ofthe Circle. I detected and was annoyed by the R--D. I determined thelatitude. I exhibited the separate results for N. P. D. Of stars inledger, and their means in Catalogue. I investigated from myobservations the place of equinox and the obliquity of the ecliptic. I made another series of observations of Jupiter's 4th Satellite, forthe mass of Jupiter. I observed the solar eclipse with the Equatoreal, by a method then first introduced, which I have since used severaltimes at Cambridge and Greenwich with excellent effect. The Moon andthe Planets were usually observed till near two in the morning. Correction for defective illumination applied when necessary. The volume is very complete, the only deficiency being inthe observation of Moon and Planets through the severe morninghours. In 1834 the only novelties are--examination of the graduationsof the declination circle of the Equatoreal (excessively bad):observations of a spot on Jupiter for rotation, and of Mars andstars. In 1835 (including January 1836) there is a more completeexamination of the Equatoreal graduations: parallax and refraction forEquatoreal observations: a spot on Jupiter: a series of observationson Jupiter's 4th Satellite for the mass of Jupiter: Mars and stars:Halley's Comet (the best series of observations which could be made inthe season): and a short series of meteorological observations, on aplan suggested by Sir John Herschel then at the Cape of Good Hope. "I cannot tell precisely in which year I introduced the followinguseful custom. Towards the end of each year I procured a pocket-bookfor the following year with a space for every day, and carefullyexamining all the sources of elements of observations, and determiningthe observations to be made every day, I inserted them in thepocket-book. This system gave wonderful steadiness to the plan ofobservations for the next year. The system has been maintained ingreat perfection at the Observatory of Greenwich. (The first of thesepocket-books which Prof. Adams has found is that for 1833. ) Printedskeleton forms were introduced for all calculations from 1828. In theGreenwich Observatory Library there is a collection, I believecomplete, of printed papers commencing with my manifesto, andcontaining all Syndicate Reports except for 1833 (when perhaps therewas none). It seems from these that my first written Report onObservations, &c. , was on May 30th, 1834. The first Syndicate Reportis on May 25th, 1829. " * * * * * A few remarks on Airy's private life and friends during his residenceat Cambridge Observatory may be here appropriately inserted. Amid the laborious occupations recorded in the foregoing pages, hissocial life and surroundings appear to have been most pleasant andcongenial. At that period there were in residence in Cambridge, andparticularly at Trinity, a large number of very brilliant men. Airywas essentially a Cambridge man. He had come up poor and friendless:he had gained friends and fame at the University, and his whole workhad been done there. From the frequent references in after times bothby him and his wife to their life at Cambridge, it is clear that theyhad a very pleasant recollection of it, and that the social gatheringsthere were remarkably attractive. He has himself recorded that withWhewell and Sedgwick, and his accomplished sisters-in-law, who werefrequently on long visits at the Observatory, they formed prettynearly one family. His friendship with Whewell was very close. Although Whewell was attimes hasty, and rough-mannered, and even extremely rude, yet he wasgenerous and large-minded, and thoroughly upright. [Footnote: Thefollowing passage occurs in a letter from Airy to his wife, dated1845, Sept. 17th: "I am sorry that ---- speaks in such terms of the'Grand Master, ' as she used to be so proud of him: it is only thosewho have _well_ gone through the ordeal of quarrels with him andalmost insults from him, like Sheepshanks and me, that thoroughlyappreciate the good that is in him: I am sure he will never want agood word from me. "] In power of mind, in pursuits, and interests, Airy had more in common with Whewell than with any other of hisfriends. It was with Whewell that he undertook the experiments atDolcoath: it was to Whewell that he first communicated the result ofhis remarkable investigation of the Long Inequality of Venus and theEarth; and some of his Optical researches were conducted jointly withWhewell. Whewell took his degree in 1816, seven years before Airy, andhis reputation, both for mathematical and all-round knowledge, wasextremely and deservedly great, but he was always most generous in hisrecognition of Airy's powers. Thus in a letter of Mar. 16th, 1823(Life of William Whewell by Mrs Stair Douglas), he says, "Airy iscertainly a most extraordinary man, and deserves everything that canbe said of him"; and again in the autumn of 1826 he writes to hisaunt, "You mentioned a difficulty which had occurred to you in one ofyour late letters; how Airy should be made Professor while I was here, who, being your nephew, must of course, on that account, deserve itbetter than he could. Now it is a thing which you will think odd, butit is nevertheless true, that Airy is a better mathematician than yournephew, and has moreover been much more employed of late in suchstudies. . . . Seriously speaking, Airy is by very much the best personthey could have chosen for the situation, and few things have given meso much pleasure as his election. " How much Whewell depended upon hisfriends at the Observatory may be gathered from a letter which hewrote to his sister on Dec. 21st, 1833. "We have lately been in alarmhere on the subject of illness. Two very near friends of mine, Prof. And Mrs Airy, have had the scarlet fever at the same time; shemore slightly, he very severely. They are now, I am thankful to say, doing well and recovering rapidly. You will recollect that I wasstaying with them at her father's in Derbyshire in the summer. Theyare, I think, two of the most admirable and delightful persons thatthe world contains. " And again on Dec. 20th, 1835, he wrote to hissister Ann, "My friends--I may almost say my dearest friends--Professor Airy and his family have left Cambridge, he beingappointed Astronomer Royal at Greenwich--to me an irreparable loss;but I shall probably go and see how they look in their new abode. "Their close intercourse was naturally interrupted by Airy's removal toGreenwich, but their friendly feelings and mutual respect continuedwithout material break till Whewell's death. There was frequentcorrespondence between them, especially on matters connected with theconduct and teaching of the University, in which they both took a keeninterest, and a warm welcome at Trinity Lodge always awaited Mr andMrs Airy when they visited Cambridge. In a letter written to Mrs StairDouglas on Feb. 11th, 1882, enclosing some of Whewell's letters, thereoccurs the following passage: "After the decease of Mrs Whewell, Whewell wrote to my wife a mournful letter, telling her of hismelancholy state, and asking her to visit him at the Lodge for a fewdays. And she did go, and did the honours of the house for severaldays. You will gather from this the relation in which the familiesstood. " Whewell died on Mar. 6th, 1866, from the effects of a fallfrom his horse, and the following extract is from a letter written byAiry to Whewell's niece, Mrs Sumner Gibson, on hearing of the death ofhis old friend: "The Master was, I believe, my oldest surviving friend (beyond my ownfamily), and, after an acquaintance of 46 years, I must have been oneof his oldest friends. We have during that time been connectedprivately and officially: we travelled together and experimentedtogether: and as opportunity served (but I need not say in verydifferent degrees) we both laboured for our College and University. Aterrible blank is left on my mind. " Sedgwick was probably 15 years older than Airy: he took his degree in1808. But the astonishing buoyancy of spirits and bonhomie of Sedgwickfitted him for all ages alike. He was undoubtedly the most popular manin Cambridge in modern times. His ability, his brightness and wit, hisfearless honesty and uprightness, his plain-speaking and good humour, rendered him a universal favourite. His close alliance with Airy wasmuch more social than scientific. It is true that they made somegeological excursions together, but, at any rate with Airy, it was farmore by way of recreation than of serious study, and Sedgwick'sscience was entirely geological. Their friendship continued tillSedgwick's death, though it was once or twice imperilled by Sedgwick'simpulsive and hasty nature. Peacock took his degree in 1813 (Herschel's year), and was thereforeprobably 10 years older than Airy. He was the earliest and staunchestfriend of Airy in his undergraduate years, encouraged him in everypossible way, lent him books, assisted him in his studies, helped himwith wise advice on many occasions, and took the greatest interest inhis success. He was a good and advanced mathematician, and with agreat deal of shrewdness and common-sense he united a singularkindness and gentleness of manner. It is therefore not to be wonderedat that he was regarded by Airy with the greatest esteem andaffection, and though they were afterwards separated, by Peacockbecoming Dean of Ely and Airy Astronomer Royal, yet their warmfriendship was never broken. The following letter, written by Airy toMrs Peacock on receiving the news of the death of the Dean, wellexpresses his feelings towards his old friend: TRINITY LODGE, CAMBRIDGE, _1858, Dec. 4_. MY DEAR MADAM, I have desired for some time to express to you my sympathies onoccasion of the sad bereavement which has come upon me perhaps asstrongly as upon any one not connected by family ties with my latefriend. But I can scarcely give you an idea how every disposablemoment of my time has been occupied. I am now called to Cambridge onbusiness, and I seize the first free time to write to you. My late friend was the first person whom I knew in College (I had anintroduction to him when I went up as freshman). From the first, hedesired me to consider the introduction not as entitling me to a mereformal recognition from him, but as authorizing me at all times tocall on him for any assistance which I might require. And this wasfully carried out: I referred to him in every difficulty: I had theentire command of his rooms and library (a very important aid infollowing the new course of mathematics which he had been soinstrumental in introducing into the University) in his occasionalabsences: and in all respects I looked to him as to a parent. All mydebts to other friends in the University added together are notcomparable to what I owe to the late Dean. Latterly I need not say that I owed much to him and that I owe much toyou for your kind notice of my two sons, even since the sad eventwhich has put it out of his power to do more. In the past summer, looking to my custom of making a visit toCambridge in some part of the October Term, I had determined that avisit to Ely this year should not depend on the chance of being freeto leave Cambridge, but that, if it should be found convenient toyourself and the Dean, the first journey should be made to Ely. Iwish that I had formed the same resolution one or two years ago. With many thanks for your kindness, and with deep sympathy on thisoccasion, I am, My dear Madam, Yours very faithfully, G. B. AIRY. Sheepshanks was a Fellow of Trinity, in orders: he was probably sevenyears older than Airy (he took his degree in 1816). He was not one ofAiry's earliest friends, but he had a great taste and liking forastronomy, and the friendship between them when once establishedbecame very close. He was a very staunch and fearless friend, an ableand incisive writer, and remarkably energetic and diligent inastronomical investigations. He, or his sister, Miss Sheepshanks, hada house in London, and Sheepshanks was very much in London, and busiedhimself extremely with the work of the Royal Observatory, that of theBoard of Longitude, and miscellaneous astronomical matters. He wasmost hospitable to his friends, and while Airy resided at Cambridgehis house was always open to receive him on his frequent visits totown. In the various polemical discussions on scientific matters inwhich Airy was engaged, Sheepshanks was an invaluable ally, and afterAiry's removal to Greenwich had more or less separated him from hisCambridge friends, Sheepshanks was still associated with him and tooka keen interest in his Greenwich work. And this continued tillSheepshanks's death. The warmest friendship always subsisted betweenthe family at the Observatory and Mr and Miss Sheepshanks. There were many other friends, able and talented men, but these fourwere the chief, and it is curious to note that they were all mucholder than Airy. It would seem as if Airy's knowledge had matured inso remarkable a manner, and the original work that he produced was sobrilliant and copious, that by common consent he ranked with men whowere much his seniors: and the natural gravity and decorum of hismanners when quite a young man well supported the idea of an ageconsiderably greater than was actually the case. CHAPTER V. AT GREENWICH OBSERVATORY--1836 TO 1846. 1836 "Through the last quarter of 1835 I had kept everything going on atthe Greenwich Observatory in the same manner in which Mr Pond hadcarried it on. With the beginning of 1836 my new system began. I hadalready prepared 30 printed skeleton forms (a system totally unknownto Mr Pond) which were now brought into use. And, having seen theutility of the Copying Press in merchants' offices, I procuredone. From this time my correspondence, public and private, isexceedingly perfect. "At this time the dwelling house was still unconnected with theObservatory. It had no staircase to the Octagon Room. Four new roomshad been built for me on the western side of the dwelling house, butthey were not yet habitable. The North-east Dome ground floor wasstill a passage room. The North Terrace was the official passage tothe North-west Dome, where there was a miserable Equatoreal, and tothe 25-foot Zenith Tube (in a square tower like a steeple, whichconnected the N. W. Dome with Flamsteed's house). The southern boundaryof the garden ran down a hollow which divides the peninsula from thesite of the present Magnetic Observatory, in such a manner that theprincipal part of the garden was fully exposed to the public. TheComputing Room was a most pitiful little room. There was so littleroom for me that I transported the principal table to a room in myhouse, where I conducted much of my own official business. A largeuseless reflecting telescope (Ramage's), on the plan and nearly of thesize of Sir W. Herschel's principal telescope, encumbered the centreof the Front Court. "On Jan. 11th I addressed Mr Buck, agent of the Princess Sophia ofGloucester, Ranger of Greenwich Park, for leave to enclose a portionof the ground overlooking my garden. This was soon granted, and I waspartially delivered from the inconvenience of the public gaze. Theliberation was not complete till the Magnetic ground was enclosed in1837. "In the inferior departments of the Admiralty, especially in theHydrographic Office (then represented by Captain Beaufort) with whichI was principally connected, the Observatory was considered rather asa place for managing Government chronometers than as a place ofscience. The preceding First Assistant (Taylor) had kept a book ofletter references, and I found that out of 840 letters, 820 related toGovernment chronometers only. On Jan. 17th I mentally sketched myregulations for my own share in chronometer business. I had somecorrespondence with Captain Beaufort, but we could not agree, and thematter was referred to the Admiralty. Finally arrangements were madewhich put the chronometer business in proper subordination to thescientific charge of the Observatory. "In my first negociations with the Admiralty referring to acceptanceof the office of Astronomer Royal, in 1834, Lord Auckland being thenFirst Lord of the Admiralty, I had stipulated that, as my successor atCambridge would be unprepared to carry on my Lectures, I should havepermission to give a final course of Lectures there. At the end of1835 Lord Auckland was succeeded by Lord Minto: I claimed thepermission from him and he refused it. When this was known inCambridge a petition was presented by many Cambridge residents, andLord Minto yielded. On April 18th I went to Cambridge with my wife, residing at the Bull Inn, and began Lectures on April 21st: theycontinued (apparently) to May 27th. My lecture-room was crowded (thenumber of names was 110) and the lectures gave great satisfaction. Ioffered to the Admiralty to put all the profits in their hands, andtransmitted a cheque to the Accountant General of the Navy: but theAdmiralty declined to receive them. "On June 4th the Annual Visitation of the Observatory was held, MrF. Baily in the Chair. I presented a written Report on the Observatory(a custom which I had introduced at Cambridge) in which I did notsuppress the expression of my feelings about chronometer business. TheHydrographer, Captain Beaufort, who was one of the Official Visitors, was irritated: and by his influence the Report was not printed. Ikept it and succeeding Reports safe for three years, and then theBoard of Visitors agreed to print them; and four Reports were printedtogether, and bound with the Greenwich Observations of 1838. "In the course of this year I completed the volume of Observationsmade at Cambridge Observatory in 1835 and on Nov. 10th the printedcopies were distributed. About the end of 1835 the Dome for theNorthumberland Telescope was erected: but apparently the polar framewas not erected. " The following account of an accident which occurred during theconstruction of the dome is extracted from a letter by Airy to hiswife dated 1836 Jan. 31st. "The workmen's account of the dome blowingoff is very curious: it must have been a strange gust. It startedsuddenly when the men were all inside and Beaumont was looking up atit: the cannon balls were thrown in with great violence (one of themgoing between the spokes of Ransomes' large casting), and instantlyafter the dome had started, the boards of the outside scaffoldingwhich had been tossed up by the same gust dropped down into the gapwhich the dome had left. It is a wonder that none of the men were hurtand that the iron was not broken. The dome is quite covered and Ithink does not look so well as when the hooping was visible. " "Previous to 1836 I had begun to contemplate the attachment ofMagnetic Observations to the Observatory, and had corresponded withProf. Christie, Prof. Lloyd, Prof. J. D. Forbes, and Mr Gauss on thesubject. On Jan. 12th 1836 I addressed a formal letter to theAdmiralty, and on Jan. 18th received their answer that they hadreferred it to the Board of Visitors. On March 25th I receivedauthority for the expenditure of _£30_, and I believe that I thenordered Merz's 2-foot magnet. The Visitors met on Feb. 26th and aftersome discussion the site was chosen and the extent of ground generallydefined, and on Dec. 22nd Mr Spring Rice (Lord Monteagle) asChancellor of the Exchequer virtually effected the transfer of theground. But no further steps were taken in 1836. A letter on asystematic course of magnetic observations in various parts of theworld was addressed by Baron Alexander Humboldt to the Duke of Sussex, President of the Royal Society; and was referred to Prof. Christie andme. We reported on it on June 9th 1836, strongly recommending theadoption of the scheme. "A plan had been proposed by the Promoters of the London and GravesendRailway (Col. Landman, Engineer) for carrying a railway at high levelacross the bottom of the Park. On Jan. 9th I received orders from theAdmiralty to examine into its possible effect in producing vibrationsin the Observatory. After much correspondence, examination of ground, &c. , I fixed upon a part of the Greenwich Railway (not yet opened fortraffic) near the place where the Croydon trunk line now joins it, asthe place for trains to run upon, while I made observations with atelescope viewing a collimator by reflection in mercury at thedistance of 500 feet. The experiments were made on Jan. 25th, and Ireported on Feb. 4th. It was shewn that there would be some danger tothe Observatory. On Nov. 2nd Mr James Walker, Engineer, brought amodel of a railway to pass by tunnel under the lower part of the Park:apparently this scheme was not pressed. "In addition to the routine work of the Observatory, a special set ofobservations were made to determine the mass of Jupiter. --Also theSolar Eclipse of May 15th was observed at Greenwich in the mannerwhich I had introduced at Cambridge. --The Ordnance Zenith Sector, andthe instruments for the St Helena Observatory were brought forexamination. --Much attention was given to chronometers, and varioussteps were taken for their improvement. --I had some importantcorrespondence with Mr (Sir John) Lubbock, upon the Lunar Theorygenerally and his proposed empirical lunar tables. This was the firstgerm of the great reduction of Lunar Observations which I subsequentlycarried out. --In October I was nominated on the Council of the RoyalSociety, having been admitted a Fellow on Feb. 18th 1836. I wasPresident of the Astronomical Society during this and the precedingyear (1836 and 1835). "My connection with Groombridge's Catalogue of Stars began in 1832, and the examination, in concert with Mr Baily, of the edition printedby Mr Henry Taylor, resulted in its condemnation. In 1834 Ivolunteered to the Admiralty to prepare a new edition, and receivedtheir thanks and their authority for proceeding. It required a greatdeal of examination of details, and much time was spent on it in 1836:but it was not brought to the state of readiness for press. "My predecessor, Mr Pond, died on Sept. 7th 1836, and was interred inHalley's tomb in Lee churchyard. " * * * * * The following letter was written by Airy in support of the applicationfor a pension to Mrs Pond, who had been left in great distress: To HENRY WARBURTON, ESQ. "The points upon which in my opinion Mr Pond's claims to the gratitudeof Astronomers are founded, are principally the following. _First_and chief, the accuracy which he introduced into all the principalobservations. This is a thing which from its nature it is extremelydifficult to estimate now, so long after the change has been made, andI can only say that so far as I can ascertain from books the change isone of very great extent: for certainty and accuracy, Astronomy isquite a different thing from what it was, and this is mainly due to MrPond. The most striking exemplification of this is in his laboriousworking out of every conceivable cause or indication of error in theCircle and the two Circles: but very great praise is also due for thenew system which he introduced in working the Transit. In comparing MrPond's systems of observation with Dr Maskelyne's, no one can avoidbeing impressed with the inferiority of Dr Maskelyne's. It is veryimportant to notice that the continental observatories which havesince attracted so much attention did not at that time exist or didnot exist in vigour. _Secondly_, the attention bestowed by Mr Pond onthose points (chiefly of sidereal astronomy) which he regarded asfundamental: to which such masses of observations were directed asentirely to remove the doubts from probable error of individualobservations or chance circumstances which have injured many otherdeterminations. _Thirdly_, the regularity of observation. The effectof all these has been that, since the commencement of Mr Pond'sresidence at Greenwich, Astronomy considered as an accuraterepresentation of the state of the heavens in the most material pointshas acquired a certainty and an extent which it never hadbefore. There is no period in the history of the science so clean. Onsome matters (in regard to the choice of observations) I might saythat my own judgment would have differed in some degree from MrPond's, but one thing could have been gained only by giving upanother, and upon the general accuracy no improvement could have beenmade. Mr Pond understood nothing of physical astronomy; but neitherdid anybody else, in England. "The supposed decrease of general efficiency in the last few years isto be ascribed to the following causes: 1. Mr Pond's ill health. 2. The inefficiency of his first assistant. 3. The oppression of business connected with chronometers. "The last of these, as I have reason to think, operated very far. Business of this nature which (necessarily) is _daily_ and_peremptory_ will always prevail over that which is _general_ and_confidential_. I will not trouble you with an account of the variousways in which the chronometer business teazed the Astronomer Royal(several alterations having been made at my representation), but shallmerely remark that much of the business had no connection whateverwith astronomy. "I beg to submit these remarks to your perusal, requesting you topoint out to me _what part_ of them should be laid before any of theKing's Ministers, _at what time, in what shape_, and to whomaddressed. I am quite sure that Mrs Pond's claims require nothing toensure favourable consideration but the impression of such a feelingof Mr Pond's astronomical merits as must be entertained by anyreasonable astronomer; and I am most anxious to assist in conveyingthis impression. "Of private history: I went to Suffolk for a week on Mar. 25th. OnSept. 19th my son Wilfrid (my fourth child) was born. In October Imade an excursion for a week round the coast of Kent. In November Iwent to my brother's house at Keysoe in Bedfordshire: I was muchexposed to cold on the return-journey, which probably aggravated theillness that soon followed. From Nov. 27th I was ill; made the lastjournal entry of the year on Dec. 6th; the next was on Jan. 14th, 1837. I find that in this year I had introduced Arthur Biddell to theTithe Commutation Office, where he was soon favourably received, andfrom which connection he obtained very profitable employment as avaluer. " 1837 "My connection with Cambridge Observatory was not yet finished. I haddetermined that I would not leave a figure to be computed by mysuccessor. In October I had (at my private expense) set Mr Glaisher towork on reducing the observations of Sun, Moon, and Planets made in1833, 1834, 1835; and subsequently had the calculations examined by MrHartnup. This employed me at times through 1837. I state here, oncefor all, that every calculation or other work in reference to theCambridge Observatory, in this and subsequent years, was done at myprivate expense. The work of the Northumberland Telescope was going onthrough the year: from Nov. 24th to 29th I was at Cambridge on theseworks. "An object-glass of 6-3/4 inches aperture (a most unusual size at thistime, when it was difficult to find a 4-inch or 5-inch glass) had beenpresented to the Greenwich Observatory by my friend Mr Sheepshanks, and on Mar. 29th I received from the Admiralty authority for mountingit equatoreally in the empty South Dome, which had been intended for acopy of the Palermo Circle. --In the month of July the Admiralty wishedfor my political assistance in a Greenwich election, but I refused togive any. --On Jan. 3rd I gave notice to the Admiralty that I hadfinished the computations of Groombridge's Catalogue, and was ready toprint. The printing was authorized and proceeded (the introduction wasfinished on Nov. 22nd), but the book was not quite ready till thebeginning of 1838. --In connection with the Cavendish experiment: onJune 10th I wrote to Spring Rice (Chancellor of the Exchequer) for_£500_, which was soon granted: and from this time there is a greatdeal of correspondence (mainly with Mr Baily) upon the details of theexperiment and the theory of the calculation. --On July 24th I saw thedescent of the parachute by which Mr Cocking was killed. I attendedthe coroner's inquest and gave evidence a few days later. "The Planetary Reductions from 1750 to 1830 had been going on: thecomputers (Glaisher, Hartnup, and Thomas) worked in the Octagon Room, and considerable advance was made. --In consequence of the agitation ofthe proposal by Mr Lubbock to form empirical tables of the Moon, forwhich I proposed to substitute complete reduction of the observationsof the Moon from 1750, the British Association at York (Oct. 23rd, 1837) appointed a deputation (including myself) to place the matterbefore the Government. I wrote on the matter to Mr Wood (Lord Halifax)stating that it would be proper to raise the First Assistant's salary, and to give me more indefinite power about employing computers. In allthese things I received cordial assistance from Mr Wood. TheChancellor of the Exchequer (Mr Spring Rice) received us on Dec. 20th:statements were furnished by me, and the business was sanctionedimmediately. --During this year I was very much engaged incorrespondence with Lubbock and others on improvements of the LunarTheory. "In the operations of 1836 and 1837 a great quantity of papers hadbeen accumulated. I had kept them in reasonably good order, tied up inbundles: but this method began to fail in convenience, as the numberincreased. The great lines of classification were however now wellunderstood. I believe it was in the latter part of the year 1837 thatI finally settled on the principle of arranging papers in packets andsubordinate packets, every paper being flat, by the use of fourpunched holes in every paper. I have never seen any principle ofarrangement comparable to this. It has been adopted with the greatestease by every assistant, and is used to the present time (1871)without alteration. "On Jan. 3rd I was informed unofficially by Mr Wood (AdmiraltySecretary) that the addition of the Magnetic Ground was sanctioned. OnFeb. 16th Mr Rhodes (an officer of the Department of Woods and Works)came to put me formally in possession of the ground. Between Apr. 26thand May 13th the ground was enclosed, and my garden was completelyprotected from the public. The plan of the building was settled, andnumerous experiments were made on various kinds of concrete: at lastit was decided to build with wood. "After a dinner given by Lord Burlington, Chancellor, the firstmeeting of the London University was held on Mar. 4th, and othersfollowed. On Apr. 18th I handed to the Chancellor a written protestagainst a vote of a salary of _£1000_ to the Registrar: which salary, in fact, the Government refused to sanction. Dissensions on thequestion of religious examination were already beginning, but I tooklittle part in them. "In 1833 Mr Henderson had resigned the superintendance of the Cape ofGood Hope Observatory, and Mr Maclear was appointed. I recommended thesame Official Instructions for him (they had included an allusion toLa Caille's Arc of Meridian) with an addition on the probability ofTrigonometrical Survey, on Aug. 8th, 1837. On Feb. 24th, 1837, I wroteto Beaufort suggesting that Bradley's Sector should be used forverifying the astronomical determinations, and subsequently receivedthe approval of the Admiralty. In June Sir J. Herschel and I had aninterview with Mr Wood on the Cape equipment generally. The Sector waserected with its new mounting, careful drawings were made of everypart, instructions were prepared for its use, and on Aug. 10th it wassent to Woolwich Dockyard and shipped for the Cape. "Of private history: On Aug. 23rd I started with my wife for anexcursion in South Wales, &c. On Sept. 9th I gave a lecture in theTown Hall of Neath. While at Swansea we received news of the death ofmy wife's father, the Rev. Richard Smith, and returned at once. --Inthis year Arthur Biddell bought the little Eye estate for me. " 1838 "Cambridge Observatory:--On Dec. 29th, 1837, I had set Mr Glaisher towork in collecting the annual results for star-places from theCambridge Observations, to form one catalogue: I examined thecalculations and the deduced catalogue, and on Dec. 14, 1838, presented it to the Royal Astronomical Society, under the title of'The First Cambridge Catalogue. '--For the Northumberland telescope Iwas engaged with Simms about the clockwork from time to time up toApr. 30th, and went to Cambridge about it. The instrument was broughtto a useable state, but some small parts were still wanting. "At Greenwich:--In April I drew up a little history of the Observatoryfor the Penny Cyclopaedia. --On June 30th the Lords of the Admiraltypaid a short visit to the Observatory: on this occasion Mr Woodsuggested a passage connecting the Observatory with thedwelling-house, and I subsequently prepared sketches for it; it wasmade in the next year. --In the course of the year the SheepshanksEquatoreal was mounted, and Encke's Comet was observed with it fromOct. 26th to Nov. 13th. --On Mar. 31st, &c. I reported to the Admiraltyon the selection of chronometers for purchase, from a long list: thiswas an important beginning of a new system. --The Magnetic Observatorywas built, in the form originally planned for it (a four-armed crosswith equal arms, one axis being in the magnetic meridian) in thebeginning of this year. (No alteration has since been made in form upto the present time, 1871, except that the north arm has beenlengthened 8 feet a few years ago. ) On May 21st a magnet was suspendedfor the first time, Mr Baily and Lieut. (afterwards Sir William)Denison being present. --Groombridge's Catalogue was finished, and onMar. 3rd I arranged for sending out copies. --The Planetary Reductionswere carried on vigorously. On May 31st, 1838, the Treasury assentedto the undertaking of the Lunar Reductions and allotted _£2, 000_ forit: preparations were made, and in the autumn 7 computers wereemployed upon it. It will easily be seen that this undertaking addedmuch to my labours and cares. --The geodetic affairs of the Cape ofGood Hope began to be actively pressed, and in February Beaufort wroteto me in consequence of an application from Maclear, asking about astandard of length for Maclear (as foundation for a geodeticsurvey). I made enquiries, and on Mar. 13th wrote to Mr Wood, alludingalso generally to the want of a National English standard after thedestruction of the Houses of Parliament. On Apr. 24th the Admiraltysanctioned my procuring proper Standard Bars. --In connection with theCavendish Experiment, I have an immense quantity of correspondencewith Mr Baily, and all the mathematics were furnished by me: theexperiment was not finished at the end of the year. --The Perturbationsof Uranus were now attracting attention. I had had some correspondenceon this subject with Dr Hussey in 1834, and in 1837 with EugèneBouvard. On Feb. 24th, of 1838, I wrote to Schumacher regarding theerror in the tabular radius-vector of Uranus, which my mode ofreducing the observations enabled me to see. "The National Standards of Length and Weight had been destroyed in thefire of the Houses of Parliament. On May 11th I received a letter fromMr Spring Rice, requesting me to act (as chairman) with a committeeconsisting of F. Baily, J. E. Drinkwater Bethune, Davies Gilbert, J. G. S. Lefevre, J. W. Lubbock, G. Peacock, and R. Sheepshanks, toreport on the steps now to be taken. I accepted the charge, and thefirst meeting was held at the Observatory on May 22nd; all subsequentmeetings in London, usually in the apartments of the RoyalAstronomical Society. I acted both as chairman and as workingsecretary. Our enquiries went into a very wide field, and I had muchcorrespondence. "On Jan. 4th Mr Wood wrote to me, mentioning that Capt. Johnson hadmade some observations on the magnetism of iron ships, and askingwhether they ought to be continued; a steamer being offered at _£50_per week. I applied to Beaufort for a copy of Johnson's Observations, and on Jan. 7th replied very fully, discouraging such observations;but recommending a train of observations expressly directed totheoretical points. On Feb. 17th I reported that I had examined theDeptford Basin, and found that it would do fairly well forexperiments. On July 14th, 1838, Capt. Beaufort wrote to me that theAdmiralty wished for experiments on the ship, the 'Rainbow, ' then inthe river, and enquired whether I would undertake them and whatassistance I desired, as for instance that of Christie or Barlow. Ireplied that one person should undertake it, either Christie, Barlow, or myself, and that a basin was desirable. On July 16th and 17th Ilooked at the basins of Woolwich and Deptford, approving thelatter. On July 21st the Admiralty gave me full powers. From July 23rdI was almost entirely employed on preparations. The course ofoperations is described in my printed Paper: the original maps, curves, and graphical projections, are in the bound MSS. : 'Correctionof Compass in Iron Ships--"Rainbow, "' at the GreenwichObservatory. The angular disturbances were found on July 26th and30th, requiring some further work on a raft, so that they were finallyworked out on Aug. 11th. I struggled hard with the numbers, but shouldnot have succeeded if it had not occurred to me to examine thehorizontal magnetic intensities. This was done on Aug. 14th, and theexplanation of the whole was suggested at once: graphical projectionswere made on Aug. 16th and 17th for comparison of my explanation withobservations, and the business was complete. On Aug. 17th and 18th Imeasured the intensity of some magnets, to be used in the ship forcorrection. It is to be remarked that, besides the effect of polarmagnetism, there was no doubt of the existence of an effect of inducedmagnetism requiring correction by other induced magnetism: andexperiments for this were made in the Magnetic Observatory. All wasready for trial: and on Aug. 20th I carried my magnets and ironcorrectors to Deptford, mounted them in the proper places, tried theship, and the compass, which had been disturbed 50 degrees to theright and 50 degrees to the left, was now sensibly correct. OnAug. 21st I reported this to the Admiralty, and on Aug. 24th I triedthe ship to Gravesend. On Aug. 30th I had the loan of her for anexpedition with a party of friends to Sheerness, and on Sept. 9th Iaccompanied her to Gravesend, on her first voyage to Antwerp. --OnOct. 5th application was made to me by the owner of the 'Ironsides' tocorrect her compasses. In consequence of this I went to Liverpool onOct. 25th, and on this occasion made a very important improvement inthe practical mode of performing the correction. --On Nov. 16th Ireported to the Admiralty in considerable detail. On Dec. 4th I had aninterview with Lord Minto (First Lord of the Admiralty) and MrWood. They refused to sanction any reward to me. --The following is acopy of the report of the Captain of the 'Rainbow' after her voyage toAntwerp: 'Having had the command of the Rainbow steamer the twovoyages between London and Antwerp, I have the pleasure to inform youthat I am perfectly satisfied as to the correctness of the compasses, and feel quite certain they will continue so. I took particular noticefrom land to land from our departure and found the bearings by compassto be exact. '"--The following extracts from letters to his wife referto the "Ironsides": on Oct. 28th 1838 he writes, "I worked up theobservations so much as to see that the compass disturbance is not sogreat as in the 'Rainbow' (35° instead of 50°), but quite enough tomake the vessel worthless; and that it is quite different in directionfrom that in the 'Rainbow'--so that if they had stolen one of the'Rainbow' correctors and put it into this ship it would have been muchworse than before. " And on Nov. 1st he writes, "On Wednesday I againwent to the ship and tried small alterations in the correctors: I amconfident now that the thing is very near, but we were most abominablybaffled by the sluggishness of the compass. " "The University of London:--On Jan. 6th I attended a sub-committeemeeting on the minimum of acquirements for B. A. Degree, and variousmeetings of the Senate. On July 14th I intimated to Mr Spring Rice mywish to resign. I had various correspondence, especially with MrLubbock, and on Dec. 13th I wrote to him on the necessity of stipendsto Members of Senate. The dissensions on religious examination becamevery strong. I took a middle course, demanding examination in thelanguages and books, but absolutely refusing to claim any religiousassent. I expressed this to Dr Jerrard, the principal representativeon the religious side, by calling on him to substitute the words'Recognition of Christian Literature' for 'Recognition of ChristianReligion': I addressed a printed letter to Lord Burlington(Chancellor) and the Members of the Senate, on this subject. "Of private history: In January I made a short excursion in Norfolkand Suffolk, and visited Prof. Sedgwick at Norwich. In April I paid ashort visit to Mr Courtney at Sanderstead, with my wife. On June 14thmy son Hubert was born. In September I went with my sister byCambridge, &c. , to Luddington, where I made much enquiry concerning myfather and the family of Airy who had long been settled there. We thenvisited various places in Yorkshire, and arrived at Brampton, nearChesterfield, where Mrs Smith, my wife's mother, now resided. Andreturned by Rugby. I had much correspondence with my brother and forhim about private pupils and a better church living. I complained tothe Bishop of Norwich about the mutilation of a celebrated monument inPlayford Church by the incumbent and curate. " The following extracts are from letters to his wife relating to theabove-mentioned journeys: CLOSE, NORWICH. _1838, Jan. 21_. I do not know what degree of cold you may have had last night, buthere it was (I believe) colder than before--thermometer close to thehouse at 3°. I have not suffered at all. However I do not intend to goto Lowestoft. BRAMPTON. _1838, Sept. 30th_. We began to think that we had seen enough of Scarborough, so we took achaise in the afternoon to Pickering, a small agricultural town, andlodged in a comfortable inn there. On Wednesday morning at 8 westarted by the railroad for Whitby, in a huge carriage denominated theLady Hilda capable of containing 40 persons or more drawn by onehorse, or in the steep parts of the railway by two horses. The roadgoes through a set of defiles of the eastern moorlands of Yorkshirewhich are extremely pretty: at first woody and rich, then graduallypoorer, and at last opening on a black moor with higher moors insight: descending in one part by a long crooked inclined plane, thecarriage drawing up another load by its weight: through a littletunnel: and then along a valley to Whitby. The rate of travelling wasabout 10 miles an hour. Betsy declares that it was the most agreeabletravelling that she ever had. Yesterday (Saturday) Caroline drove Betsy and Miss Barnes drove me toClay Cross to see the works at the great railroad tunnel there. Comingfrom the north, the railroad passes up the Chesterfield valley closeby the town and continues up the same valley, till it is necessary forit to enter the valley which runs the opposite way towards Buttersley:the tunnel passes under the high ground between these two vallies: sothat it is in reality at the water-shed: it is to be I think more thana mile long, and when finished 27 feet clear in height, so it is agrand place. We saw the preparations for a blast, and heard it fired:the ladies stopping their ears in due form. 1839 "Cambridge Observatory:--On Mar. 7th I went to Cambridge on thebusiness of the Northumberland Telescope: I was subsequently engagedon the accounts, and on Aug. 16th I finally resigned it toProf. Challis, who accepted it on Aug. 19th. On Sept. 11th Icommunicated its completion and the settlement of accounts to the Dukeof Northumberland. The total expense was _£1938. 9s. 2d. _ + 15000francs for the object-glass. "At Greenwich Observatory:--On Jan. 3rd I received the last revise ofthe 1837 Observations, and on Jan. 8th the first sheet for 1838. --InJuly I report on selection from a long list of chronometers which hadbeen on trial, and on Sept. 2nd I pointed out to Capt. Beaufort thatthe system of offering only one price would be ruinous to themanufacture of chronometers, and to the character of those supplied tothe Admiralty: and that I would undertake any trouble of classifyingthe chronometers tried. This letter introduced the system still in use(1871), which has been most beneficial to the manufacture. OnSept. 11th I proposed that all trials begin in the first week ofJanuary: this also has been in use as an established system to thepresent time. --It was pointed out to me that a certain chronometer wasaffected by external magnetic power. I remedied this by placing underit a free compass magnet: a stand was specially prepared for it. Ihave never found another chronometer sensibly affected bymagnetism. --In November and December I tried my new double-imagemicrometer. --Between May 16th and Oct. 13th a fireproof room wasconstructed in the southern part of the quadrant room; and in Novembera small shed was erected over the entrance to the North Terrace. --Theposition of the free Meridional Magnet (now mounted in the MagneticObservatory) was observed at every 5 m. Through 24 hours on Feb. 22ndand 23rd, May 24th and 25th, Aug. 30th and 31st, and Nov. 29th and30th. This was done in cooperation with the system of the MagneticUnion established by Gauss in Germany. --The Reduction of the GreenwichPlanetary and Lunar Observations, 1750 to 1830, went on steadily. Ihad six and sometimes seven computers constantly at work, in theOctagon Room. --As in 1838 I had a great amount of correspondence withMr Baily on the Cavendish Experiment. --I attended as regularly as Icould to the business of the University of London. The religiousquestion did not rise very prominently. I took a very active part, andhave a great deal of correspondence, on the nature of the intendedexaminations in Hydrography and Civil Engineering. --On the StandardsCommission the chief work was in external enquiries. --On June 6th Ihad enquiries from John Quincey Adams (U. S. A. ) on the expense, &c. , ofobservatories: an observatory was contemplated in America. --I hadcorrespondence about the proposed establishment of observatories atDurham, Glasgow, and Liverpool. "I had in this year a great deal of troublesome and on the wholeunpleasant correspondence with the Admiralty about the correction ofthe compass in iron ships. I naturally expected some acknowledgment ofan important service rendered to Navigation: but the Admiraltyperemptorily refused it. My account of the Experiments &c. For theRoyal Society is dated April 9th. The general success of theundertaking soon became notorious, and (as I understood) ledimmediately to extensive building of iron ships: and it led also toapplications to me for correction of compasses. On Jan. 9th I wasaddressed in reference to the Royal Sovereign and Royal George atLiverpool; July 18th the Orwell; May 11th two Russian ships built onthe Thames; Sept. 4th the ships of the Lancaster Company. "I had much work in connection with the Cape of Good Hope Observatory, chiefly relating to the instrumental equipment and to the geodeticalwork. As it was considered advisable that any base measured in theCape Colony should be measured with compensation bars, I applied toMajor Jervis for the loan of those belonging to the East IndianSurvey, but he positively refused to lend them. On Jan. 20th I appliedto Col. Colby for the compensation bars of the British Survey, and heimmediately assented to lending them. Col. Colby had suggested to theOrdnance Department that Capt. Henderson and several sappers should besent to use the measuring bars, and it was so arranged. It stillappeared desirable to have the command of some soldiers from theGarrison of Cape Town, and this matter was soon arranged with themilitary authorities by the Admiralty. "The following are the principal points of my private history: it wasa very sad year. On Jan. 24th I went with my wife to Norwich, on avisit to Prof. Sedgwick, and in June I visited Sir J. Herschel atSlough. On June 13th my dear boy Arthur was taken ill: his malady soonproved to be scarlet fever, of which he died on June 24th at 7 in themorning. It was arranged that he should be buried in Playfordchurchyard on the 28th, and on that day I proceeded to Playford withmy wife and my eldest son George Richard. At Chelmsford my son wasattacked with slight sickness, and being a little unwell did notattend his brother's funeral. On July 1st at 4h. 15m. In the morning healso died: he had some time before suffered severely from an attack ofmeasles, and it seemed probable that his brain had suffered. On July5th he was buried by the side of his brother Arthur in Playfordchurchyard. --On July 23rd I went to Colchester on my way toWalton-on-the-Naze, with my wife and all my family; all my childrenhad been touched, though very lightly, with the scarlet fever. --It wasnear the end of this year that my mother quitted the house (Luck's) atPlayford, and came to live with me at Greenwich Observatory, where shelived till her death; having her own attendant, and living in perfectconfidence with my wife and myself, and being I trust as happy as heryears and widowhood permitted. My sister also lived with me at theObservatory. " 1840 "In the latter part of 1839, and through 1840, I had muchcorrespondence with the Admiralty, in which I obtained a completeaccount of the transfer of the Observatory from the OrdnanceDepartment to the Admiralty, and the transfer of the Visitation of theObservatory from the Royal Society to the present Board ofVisitors. In 1840 I found that the papers of the Board of Longitudewere divided between the Royal Society and the Admiralty: I obtainedthe consent of both to bring them to the Observatory. "In this year I began to arrange about an annual dinner to be held atthe Visitation. --My double-image micrometer was much used forobservations of circumpolar double stars. --In Magnetism andMeteorology, certain quarterly observations were kept up; but inNovember the system of incessant eye-observations was commenced. Irefused to commence this until I had secured a 'Watchman's Clock' formechanical verification of the regular attendance of theAssistants. --With regard to chronometers: In this year, for the firsttime, I took the very important step of publishing the rates obtainedby comparisons at the Observatory. I confined myself on this occasionto the chronometers purchased by the Admiralty. In March apigeon-house was made for exposure of chronometers to cold. --The Lunarand Planetary Reductions were going on steadily. --I was consultedabout an Observatory at Oxford, where I supported the introduction ofthe Heliometer. --The stipend of the Bakerian Lecture was paid to mefor my explanation of Brewster's new prismatic fringes. --The businessof the Cape Observatory and Survey occupied much of my time. --In 1838the Rev. H. J. Rose (Editor of the Encyclopaedia Metropolitana) hadproposed my writing a Paper on Tides, &c. ; In Oct. 1840 I gave himnotice that I must connect Tides with Waves, and in that way I willtake up the subject. Much correspondence on Tides, &c. , with Whewelland others followed. "With regard to the Magnetical and Meteorological Establishment. OnJune 18th Mr Lubbock reported from the Committee of Physics of theRoyal Society to the Council in favour of a Magnetic andMeteorological Observatory near London. After correspondence withSheepshanks, Lord Northampton, and Herschel, I wrote to the Council onJuly 9th, pointing out what the Admiralty had done at Greenwich, andoffering to cooperate. In a letter to Lord Minto I stated that myestimate was _£550_, including _£100_ to the First Assistant:Lubbock's was _£3, 000_. On Aug. 11th the Treasury assented, limitingit to the duration of Ross's voyage. On Aug. 17th Wheatstone looked atour buildings and was satisfied. My estimate was sent to theAdmiralty, viz. _£150_ outfit, _£520_ annual expense; and Glaisher tobe Superintendent. I believe this was allowed for the present; forthe following year it was placed on the Estimates. Most of thecontemplated observations were begun before the end of 1840: as muchas possible in conformity with the Royal Society's plan. Mr Hind(subsequently the Superintendent of the Nautical Almanac) and Mr Paulwere the first extra assistants. "Of private history. On Feb. 29th I went to Cambridge with my Paper onthe Going Fusee. On Mar. 27th I went to visit Mrs Smith, my wife'smother, at Brampton near Chesterfield. I made a short visit toPlayford in April and a short expedition to Winchester, Portsmouth, &c. , in June. From Sept. 5th to Oct. 3rd I was travelling in theNorth of England and South of Scotland. " [This was an extremely activeand interesting journey, in the course of which a great number ofplaces were visited by Airy, especially places on the Border mentionedin Scott's Poems, which always had a great attraction for him. He alsoattended a Meeting of the British Association at Glasgow and made astatement regarding the Planetary and Lunar Reductions: and looked ata site for the Glasgow Observatory. ] "In November I went for a shorttime to Cambridge and to Keysoe (my brother's residence). OnDec. 26th my daughter Hilda was born (subsequently married toE. J. Routh). In this year I had a loss of _£350_ by a fire on my Eyeestate. " * * * * * The following extracts are from letters to his wife. Some of themrelate to matters of general interest. They are all of themcharacteristic, and serve to shew the keen interest which he took inmatters around him, and especially in architecture and scenery. Thefirst letter relates to his journey from Chesterfield on the previousday. FLAMSTEED HOUSE, _1840, April 2_. I was obliged to put up with an outside place to Derby yesterday, muchagainst my will, for I was apprehensive that the cold would bring onthe pain in my face. Of that I had not much; but I have caughtsomething of sore throat and catarrh. The coach came up at about 22minutes past 8. It arrived in Derby at 20 minutes or less past 11(same guard and coachman who brought us), and drew up in the streetopposite the inn at which we got no dinner, abreast of an omnibus. Ihad to go to a coach office opposite the inn to pay and be booked forLondon, and was duly set down in a way-bill with _name_; and thenentered the omnibus: was transferred to the Railway Station, and thenreceived the Railway Ticket by shouting out my name. If you shouldcome the same way, you would find it convenient to book your place atChesterfield to London by your name (paying for the whole, namely, coach fare, omnibus fare _-/6_, and railway fare _£1. 15s. 0d. _ firstclass). Then you will only have to step out of the coach into theomnibus, and to scream out once or twice to the guard to make surethat you are entered in the way-bill and that your luggage is put onthe omnibus. * * * * * FLAMSTEED HOUSE, GREENWICH, _1840, April 15_. I forgot to tell you that at Lord Northampton's I saw some specimensof the Daguerrotype, pictures made by the Camera Obscura, and theysurpass in beauty of execution anything that I could haveimagined. Baily who has two or three has promised to lend them foryour inspection when you return. Also I saw some post-office stampsand stamped envelopes: I do not much admire the latter. * * * * * The following relates to the fire on his Eye farm, referred to above: PLAYFORD, _1840, April 23_. On Wednesday (yesterday) went with my uncle to the Eye Estate, to seethe effects of the fire. The farming buildings of every kind are ascompletely cleared away as if they had been mown down: not a bit ofanything but one or two short brick walls and the brick foundations ofthe barns and stacks. The aspect of the place is much changed, becausein approaching the house you do not see it upon a back-ground ofbarns, &c. , but standing alone. The house is in particularly neat andgood order. I did not think it at all worth while to make troublesomeenquiries of the people who reside there, but took Mr Case'saccount. There seems no doubt that the fire was caused by themaid-servant throwing cinders into a sort of muck-place into whichthey had been commonly thrown. I suppose there was after all this dryweather straw or muck drier than usual, and the cinders were hotterthan usual. The whole was on fire in an exceedingly short time; andeverything was down in less than an hour. Two engines came from Eye, and all the population of the town (as the fire began shortly aftertwo o'clock in the afternoon). It is entirely owing to these that myhouse, and the farm (Sewell's) on the opposite side of the road, werenot burned down. At the beginning of the fire the wind was N. E. Whichblew directly towards the opposite farm (Sewell's): although thenearest part of it (tiled dwelling house) was 100 yards off or nearit, and the great barn (thatched roof) considerably further, yet bothwere set on fire several times. All this while, the tail of my housewas growing very hot: and shortly after the buildings fell in burningruins, the wind changed to N. W. , blowing directly to my house. If thischange had happened while the buildings were standing and burning, there would have been no possibility of saving the house. As it was, the solder is melted from the window next the farm-yard, and the roofwas set on fire in three or four places. One engine was kept workingon my house and one on the opposite farm. A large pond was prettynearly emptied. Mr Case's horses and bullocks were got out, notwithout great difficulty, as the progress of the fire was fearfullyrapid. A sow and nine pigs were burnt, and a large hog ran out burntso much that the people killed it immediately. * * * * * GEORGE INN, WINCHESTER, _1840, June 21_. At Winchester we established ourselves at the George and then withoutdelay proceeded to St Cross. I did not know before the nature of itshospital establishment, but I find that it is a veritable set ofalms-houses. The church is a most curious specimen of the latestNorman. I never saw one so well marked before--Norman ornaments onpointed arches, pilasters detached with cushion capitals, and varioussigns: and it is clearly an instance of that state of the style whenpeople had been forced by the difficulties and inelegancies of theround arch in groining to adopt pointed arches for groining but hadnot learnt to use them for windows. . . . . . . This morning after breakfastwent to the Cathedral (looking by the way at a curious old cross inthe street). I thought that its inside was wholly Norman, and was mostagreeably surprised by finding the whole inside groined in every partwith excellent late decorated or perpendicular work. Yet there areseveral signs about it which lead me to think that the whole insidehas been Norman, and even that the pilasters now worked up into theperpendicular are Norman. The transepts are most massive old Norman, with side-aisles running round their ends (which I never sawbefore). The groining of the side aisles of the nave very effectivefrom the strength of the cross ribs. The clerestory windows of thequire very large. The organ is on one side. But the best thing aboutthe quire is the wooden stall-work, of early decorated, verybeautiful. A superb Lady Chapel, of early English. * * * * * PORTSMOUTH, _1840, June 23_. We left Winchester by evening train to the Dolphin, Southampton, andslept there. At nine in the morning we went by steamboat down theriver to Ryde in the Isle of Wight: our steamer was going on toPortsmouth, but we thought it better to land at Ryde and take a boatfor ourselves. We then sailed out (rather a blowing day) to the vesselattending Col. Pasley's operations, and after a good deal of goingfrom one boat to another (the sea being so rough that our boat couldnot be got up to the ships) and a good deal of waiting, we got onboard the barge or lump in which Col. Pasley was. Here we had thesatisfaction of seeing the barrel of gunpowder lowered (there was morethan a ton of gunpowder), and seeing the divers go down to fix it, dressed in their diving helmets and supplied with air from the greatair-pump above. When all was ready and the divers had ascended again, the barge in which we were was warped away, and by a galvanic batteryin another barge (which we had seen carried there, and whoseconnection with the barrel we had seen), upon signal given by sound oftrumpet, the gunpowder was fired. The effect was most wonderful. Thefiring followed the signal instantaneously. We were at between 100 and200 yards from the place (as I judge), and the effects were asfollows. As soon as the signal was given, there was a report, louderthan a musket but not so loud as a small cannon, and a severe shockwas felt at our feet, just as if our barge had struck on arock. Almost immediately, a very slight swell was perceived over theplace of the explosion, and the water looked rather foamy: then inabout a second it began to rise, and there was the most enormousoutbreak of spray that you can conceive. It rose in one column of 60or 70 feet high, and broad at the base, resembling a stumpy sheaf withjagged masses of spray spreading out at the sides, and seemed to growoutwards till I almost feared that it was coming to us. It sunk, Isuppose, in separate parts, for it did not make any grand squash down, and then there were seen logs of wood rising, and a dense mass ofblack mud, which spread gradually round till it occupied a very largespace. Fish were stunned by it: our boatmen picked up some. It wassaid by all present that this was the best explosion which had beenseen: it was truly wonderful. Then we sailed to Portsmouth. . . . . . . Theexplosion was a thing worth going many miles to see. There were manyyachts and sailing boats out to see it (I counted 26 before they wereat the fullest), so that the scene was very gay. * * * * * Here are some notes on York Cathedral after the fire: RED LION HOTEL, REDCAR, _1840, Sept. 7_. My first letter was closed after service at York Cathedral. As soon asI had posted it, I walked sedately twice round the cathedral, and thenI found the sexton at the door, who commiserating me of my former vainapplications, and having the hope of lucre before his eyes, let mein. I saw the burnt part, which looks not melancholy butunfinished. Every bit of wood is carried away clean, with scarcely asmoke-daub to mark where it has been: the building looks as if thewalls were just prepared for a roof, but there are some deep dints inthe pavement, shewing where large masses have fallen. The lower partsof some of the columns (to the height of 8 or 10 feet) are much scaledand cracked. The windows are scarcely touched. I also refreshed mymemory of the chapter-house, which is most beautiful, and which hasmuch of its old gilding reasonably bright, and some of its old paintquite conspicuous. And I looked again at the old crypt with its lateNorman work, and at the still older crypt of the pre-existing church. * * * * * 1841 "The routine work of the Observatory in its several departments wascarried on steadily during this year. --The Camera Obscura was removedfrom the N. W. Turret of the Great Room, to make way for theAnemometer. --In Magnetism and Meteorology the most important thing wasthe great magnetic storm of Sept. 29th, which revealed a new class ofmagnetic phenomena. It was very well observed by Mr Glaisher, and Iimmediately printed and circulated an account of it. --In April Ireported that the Planetary Reductions were completed, and furnishedestimates for the printing. --In August I applied for 18, 000 copies ofthe great skeleton form for computing Lunar Tabular Places, which weregranted. --I reported, as usual, on various Papers for the RoyalSociety, and was still engaged on the Cavendish Experiment. --In theUniversity of London I attended the meeting of Dec. 8th, on thereduction of Examiners' salaries, which were extravagant. --I furnishedCol. Colby with a plan of a new Sector, still used in the BritishSurvey. --I appealed to Colby about the injury to the cistern on theGreat Gable in Cumberland, by the pile raised for the SurveySignal. --On Jan. 3rd occurred a most remarkable tidal disturbance: thetide in the Thames was 5 feet too low. I endeavoured to trace it onthe coasts, and had a vast amount of correspondence: but it elicitedlittle. "Of private history: I was a short time in Suffolk in March. --OnMar. 31st I started with my wife (whose health had suffered much) fora trip to Bath, Bristol, Cardiff, Swansea, &c. While at Swansea wereceived news on Apr. 24th of the deadly illness of my dear mother. Wetravelled by Neath and Cardiff to Bath, where I solicited a rest formy wife from my kind friend Miss Sutcliffe, and returned alone toGreenwich. My dear mother had died on the morning of the 24th. Thefuneral took place at Little Whelnetham (near Bury) on May 1st, wheremy mother was buried by the side of my father. We went to Cambridge, where my wife consulted Dr Haviland to her great advantage, andreturned to Greenwich on May 7th. --On May 14th to 16th I was atSanderstead (Rev. J. Courtney) with Whewell as one sponsor, at thechristening of my daughter Hilda. --In September I went for a trip withmy sister to Yorkshire and Cumberland, in the course of which wevisited Dent (Sedgwick's birthplace), and paid visits to MrWordsworth, Miss Southey, and Miss Bristow, returning to Greenwich onthe 30th Sept. --From June 15th to 19th I visited my brother atKeysoe. " The following extracts are from letters written to his wife while onthe above trip in Yorkshire and Cumberland: RED LION INN, REDCAR, _1841, Sept. 11_. We stopped at York: went to the Tavern Hotel. In the morning (Friday)went into the Cathedral. I think that it improves on acquaintance. Thenave is now almost filled with scaffolding for the repair of the roof, so that it has not the bare unfinished appearance that it had when Iwas there last year. The tower in which the fire began seems to be agood deal repaired: there are new mullions in its windows, &c. Westopped to hear part of the service, which was not very effective. * * * * * Here are notes of his visit to Dentdale in Yorkshire, the birthplaceof his friend Sedgwick: KING'S HEAD, KENDAL, _1841, Sept. 15_. The day was quite fine, and the hills quite clear. The ascent out ofHawes is dull; the little branch dale is simple and monotonous, and soare the hills about the great dale which are in sight. The only thingwhich interested us was the sort of bird's-eye view of Hardraw dell, which appeared a most petty and insignificant opening in the greathill side. But when we got to the top of the pass there was amagnificent view of Ingleborough. The dale which was most nearly infront of us is that which goes down to Ingleton, past the side ofIngleborough. The mountain was about nine miles distant. We turned tothe right and immediately descended Dent-dale. The three dales (toHawes, to Ingleton, and to Dent) lay their heads together in a mostamicable way, so that, when at the top, it is equally easy to descenddown either of them. We found very soon that Dent-dale is much morebeautiful than that by which we had ascended. The sides of the hillsare steeper, and perhaps higher: the bottom is richer. The road isalso better. The river is a continued succession of very pretty falls, almost all of which have scooped out the lower strata of the rock, sothat the water shoots clear over. For several miles (perhaps 10) itruns upon bare limestone without a particle of earth. From the head ofthe dale to the village of Dent is eight miles. At about half-way is anew chapel, very neat, with a transept at its west end. The village ofDent is one of the strangest places that I ever saw. Narrow street, upand down, with no possibility of two carriages bigger than children'scarts passing each other. We stopped at the head inn and enquiredabout the Geolog: but he is not in the country. We then called on hisbrother, who was much surprised and pleased to see us. His wife camein soon after (his daughter having gone with a party to see somewaterfall) and they urged us to stop and dine with them. So we walkedabout and saw every place about the house, church, and school, connected with the history of the Geolog: and then dined. I promisedthat you should call there some time when we are in the north togetherand spend a day or two with them. Mr Sedgwick says it is reported thatWhewell will take Sedbergh living (which is now vacant: TrinityCollege is patron). Then we had our chaise and went to Sedbergh. Thevery mouth of Dent-dale is more contracted than its higherparts. Sedbergh is embosomed among lumping hills. Then we had anothercarriage to drive to Kendal. * * * * * Here is a recollection of Wordsworth: SALUTATION, AMBLESIDE, _1841, Sept. 19_. We then got our dinner at Lowwood, and walked straight to Ambleside, changed our shoes, and walked on to Rydal to catch Wordsworth attea. Miss Wordsworth was being drawn about in a chair just as she wasseven years ago. I do not recollect her appearance then so as to saywhether she is much altered, but I think not. Mr Wordsworth is asfull of good talk as ever, and seems quite strong and well. MrsWordsworth looks older. Their son William was at tea, but he had comeover only for the day or evening. There was also a little girl, who Ithink is Mrs Wordsworth's niece. 1842 "In this year I commenced a troublesome work, the Description of theNorthumberland Telescope. On Sept. 9th I wrote to the Duke ofNorthumberland suggesting this, sending him a list of Plates, andsubmitting an estimate of expense _£120_. On Sept. 19th I received theDuke's assent. I applied to Prof. Challis (at the CambridgeObservatory) requesting him to receive the draughtsman, Sly, in hishouse, which he kindly consented to do. "With regard to Estimates. I now began to point out to the Admiraltythe inconvenience of furnishing separate estimates, viz. To theAdmiralty for the Astronomical Establishment, and to the Treasury forthe Magnetical and Meteorological Establishment. --The great work ofthe Lunar Reductions proceeded steadily: 14 computers were employed onthem. --With regard to the Magnetical and Meteorological Establishment:I suppose that James Ross's expedition had returned: and with this, according to the terms of the original grant, the Magnetical andMeteorological Establishments expired. There was much correspondencewith the Royal Society and the Treasury, and ultimately Sir R. Peelconsented to the continuation of the establishments to the end of1845. --In this year began my correspondence with Mr Mitchell about theCincinnati Observatory. On Aug. 25 Mr Mitchell settled himself atGreenwich, and worked for a long time in the Computing Room. --And inthis year Mr Aiken of Liverpool first wrote to me about the LiverpoolObservatory, and a great deal of correspondence followed: the planswere in fact entirely entrusted to me. --July 7th was the day of theTotal Eclipse of the Sun, which I observed with my wife at theSuperga, near Turin. I wrote an account of my observations for theRoyal Astronomical Society. --On Jan. 10th I notified to Mr Goulburnthat our Report on the Restoration of the Standards was ready, and onJan. 12th I presented it. After this followed a great deal ofcorrespondence, principally concerning the collection of authenticatedcopies of the Old Standards from all sides. --In some discussions withCapt. Shirreff, then Captain Superintendent of the Chatham Dockyard, I suggested that machinery might be made which would saw ship-timbersto their proper form, and I sent him some plans on Nov. 8th. This wasthe beginning of a correspondence which lasted long, but which led tonothing, as will appear hereafter. --On Dec. 15th, being on a visit toDean Peacock at Ely, I examined the Drainage Scoop Wheel atPrickwillow, and made a Report to him by letter, which obtainedcirculation and was well known. --On May 26th the manuscript of myarticle, 'Tides and Waves, ' for the Encyclopaedia Metropolitana wassent to the printer. I had extensive correspondence, principally onlocal tides, with Whewell and others. Tides were observed for me byColby's officers at Southampton, by myself at Christchurch and Poole, at Ipswich by Ransome's man; and a great series of observations ofIrish Tides were made on my plan under Colby's direction in June, Julyand August. --On Sept. 15th Mr Goulburn, Chancellor of the Exchequer, asked my opinion on the utility of Babbage's calculating machine, andthe propriety of expending further sums of money on it. I replied, entering fully into the matter, and giving my opinion that it wasworthless. --I was elected an Honorary Member of the Institution ofCivil Engineers, London. "The reduction and printing of the astronomical observations had beengetting into arrear: the last revise of the 1840 observations went topress on May 18th, 1842. On Aug. 18th came into operation a neworganization of Assistants' hours of attendance, &c. , required forbringing up reductions. I worked hard myself and my example had goodeffect. " His reference to this subject in his Report to the Visitorsis as follows: "I have in one of the preceding articles alluded to thebackwardness of our reductions. In those which follow it I trust thatI have sufficiently explained it. To say nothing of the loss, from illhealth, of the services of most efficient assistants, I am certainthat the quantity of current work will amply explain anybackwardness. Perhaps I may particularly mention that in theobservations of 1840 there was an unusual quantity of equatorealobservations, and the reductions attending these occupied a very greattime. But, as regards myself, there has been another cause. Thereduction of the Ancient Lunar and Planetary Observations, theattention to chronometer constructions, the proposed management of theprinting of papers relating to important operations at the Cape ofGood Hope; these and similar operations have taken up much of mytime. I trust that I am doing well in rendering Greenwich, even moredistinctly than it has been heretofore, the place of reference to allthe world for the important observations, and results of observations, on which the system of the universe is founded. As regards myself, Ihave been accustomed, in these matters, to lay aside privateconsiderations; to consider that I am not a mere Superintendent ofcurrent observations, but a Trustee for the honour of GreenwichObservatory generally, and for its utility generally to the world;nay, to consider myself not as mere Director of Greenwich Observatory, but (however unworthy personally) as British Astronomer, requiredsometimes by my office to interfere (when no personal offence isgiven) in the concerns of other establishments of the State. If theBoard supports me in this view there can be little doubt that thepresent delay of computations, relating to current observations, willbe considered by them as a very small sacrifice to the importantadvantage that may be gained by proper attention to the observationsof other times and other places. " "Of private history: In February I went for a week to Playford andNorwich, visiting Prof. Sedgwick at the latter place. On Mar. 1st mythird daughter Christabel was born. In March I paid a short visit toSir John Herschel at Hawkhurst. From June 12th to Aug. 11th I wastravelling with my wife on the Continent, being partly occupied withthe observation of the Total Eclipse of the Sun on July 7th. Thejourney was in Switzerland and North Italy. In December I went toCambridge and Ely, visiting Dr Peacock at the latter place. " From Feb. 23rd to 28th Airy was engaged on Observations of Tides atSouthampton, Christchurch, Poole, and Weymouth. During this expeditionhe wrote frequently (as he always did) to his wife on the incidents ofhis journey, and the following letters appear characteristic: KING'S ARMS, CHRISTCHURCH, OR XCHURCH, _1842, Feb. 24_. The lower of the above descriptions of my present place of abode isthe correct one, as I fearlessly assert on the authority of diversdirection-posts on the roads leading to it (by the bye this supportsmy doctrine that x in Latin was not pronounced eks but khi, becausethe latter is the first letter of Christ, for which x is heretraditionally put). Finding this morning that Yolland (who called onme as soon as I had closed the letter to you) was perfectly inclinedto go on with the tide observations at Southampton, and that hiscorporals of sappers were conducting them in the most exemplarymanner, I determined on starting at once. However we first went tolook at the New Docks (mud up to the knees) and truly it is a verygreat work. There is to be enclosed a good number of acres of water 22feet deep: one dock locked in, the other a tidal dock or basin withthat depth at low water. They are surrounded by brick walls eight feetthick at top, 10 or more at bottom; and all the parts that ever can beexposed are faced with granite. The people reckon that this work whenfinished will attract a good deal of the London commerce, and I shouldnot be surprised at it. For it is very much easier for ships to getinto Southampton than into London, and the railway carriage will makethem almost one. A very large steamer is lying in Southampton Water:the Oriental, which goes to Alexandria. The Lady Mary Wood, a largesteamer for Lisbon and Gibraltar, was lying at the pier. The said pieris a very pleasant place of promenade, the water and banks are sopretty, and there is so much liveliness of ships about it. Well Istarted in a gig, in a swashing rain, which continued off and on for agood while. Of the 21 miles, I should think that 15 were across theNew Forest. I do not much admire it. As for Norman William'sdestruction of houses and churches to make it hunting ground, that isutter nonsense which never could have been written by anybody thatever saw it: but as to hunting, except his horses wore something likemud-pattens or snow-shoes, it is difficult to conceive it. Almost thewhole Forest is like a great sponge, water standing in every part. Inthe part nearer to Xchurch forest trees, especially beeches, seem togrow well. We stopped to bait at Lyndhurst, a small place high up inthe Forest: a good view, such as it is, from the churchyard. Thehills of the Isle of Wight occasionally in sight. On approachingXchurch the chalk cliffs of the west end of the Isle of Wight (leadingto the Needles) were partly visible; and, as the sun was shining onthem, they fairly blazed. Xchurch is a small place with amagnificent-looking church (with lofty clerestory, double transept, &c. , but with much irregularity) which I propose to visitto-morrow. Also a ruin which looks like an abbey, but the people callit a castle. There is a good deal of low land about it, and the partbetween the town and the sea reminded me a good deal of the estuaryabove Cardigan, flat ill-looking bogs (generally islands) among thewater. I walked to the mouth of the river (more than two miles)passing a nice little place called Sandford, with a hotel and a lot oflodgings for summer sea-people. At the entrance of the river is acoastguard station, and this I find is the place to which I must go inthe morning to observe the tide. I had some talk with the coastguardpeople, and they assure me that the tide is really double asreported. As I came away the great full moon was rising, and I couldread in her unusually broad face (indicating her nearness to theearth) that there will be a powerful tide. I came in and have haddinner and tea, and am now going to bed, endeavouring to negociate fora breakfast at six o'clock to-morrow morning. It is raining cats anddogs. * * * * * LUCE'S HOTEL, WEYMOUTH, _1842, Feb. 27_. This morning when I got up I found that it was blowing fresh fromS. W. And the sea was bursting over the wall of the eastern extremityof the Esplanade very magnanimously. So (the swell not beingfavourable for tide-observations) I gave them up and determined to goto see the surf on the Chesil Bank. I started with my great-coat on, more for defence against the wind than against rain; but in a shorttime it began to rain, and just when I was approaching the bridgewhich connects the mainland with the point where the Chesil Bank endsat Portland (there being an arm of the sea behind the Chesil Bank) itrained and blew most dreadfully. However I kept on and mounted thebank and descended a little way towards the sea, and there was thesurf in all its glory. I cannot give you an idea of its majesticappearance. It was evidently very high, but that was not the moststriking part of it, for there was no such thing as going within aconsiderable distance of it (the occasional outbreaks of the wateradvancing so far) so that its magnitude could not be well seen. Myimpression is that the height of the surf was from 10 to 20 feet. Butthe striking part was the clouds of solid spray which formedimmediately and which completely concealed all the other operations ofthe water. They rose a good deal higher than the top of the surf, sothe state of things was this. A great swell is seen coming, growingsteeper and steeper; then it all turns over and you see a face justlike the pictures of falls of Niagara; but in a little more than onesecond this is totally lost and there is nothing before you but anenormous impenetrable cloud of white spray. In about another secondthere comes from the bottom of this cloud the foaming current of waterup the bank, and it returns grating the pebbles together till theirjar penetrates the very brain. I stood in the face of the wind andrain watching this a good while, and should have stood longer but thatI was so miserably wet. It appeared to me that the surf was higherfarther along the bank, but the air was so thickened by the rain andthe spray that I could not tell. When I returned the bad weatherabated. I have now borrowed somebody else's trowsers while mine aredrying (having got little wet in other parts, thanks to my great-coat, which successfully brought home a hundredweight of water), and do notintend to stir out again except perhaps to post this letter. * * * * * FLAMSTEED HOUSE, _1842, May 15_. Yesterday after posting the letter for you I went per steamboat toHungerford. I then found Mr Vignoles, and we trundled off together, with another engineer named Smith, picking up Stratford by the way, toWormwood Scrubs. There was a party to see the Atmospheric Railway inaction: including (among others) Sir John Burgoyne, whom I met inIreland several years ago, and Mr Pym, the Engineer of the Dublin andKingstown Railway, whom I have seen several times, and who is verysanguine about this construction; and Mr Clegg, the proposer of thescheme (the man that invented gas in its present arrangements), andMessrs Samuda, two Jews who are the owners of the experiment now goingon; and Sir James South! With the latter hero and mechanician we didnot come in contact. Unfortunately the stationary engine (for workingthe air-pump which draws the air out of the pipes and thus sucks thecarriages along) broke down during the experiment, but not till we hadseen the carriage have one right good run. And to be sure it is veryfunny to see a carriage running all alone "as if the Devil drove it"without any visible cause whatever. The mechanical arrangements wewere able to examine as well after the engine had broken down as atany time. And they are very simple and apparently very satisfactory, and there is no doubt of the mechanical practicability of the thingeven in places where locomotives can hardly be used: whether it willpay or not is doubtful. I dare say that the Commissioners' Report hastaken a very good line of discrimination. * * * * * 1843 "In March I wrote to Dr Wynter (Vice-Chancellor) at Oxford, requestingpermission to see Bradley's and Bliss's manuscript Observations, withthe view of taking a copy of them. This was granted, and the books ofTransits were subsequently copied under Mr Breen's superintendence. --The following paragraph is extracted from the Report tothe Visitors: 'In the Report of last year, I stated that ourreductions had dropped considerably in arrear. I have the satisfactionnow of stating that this arrear and very much more have beencompletely recovered, and that the reductions are now in as forward astate as at any time since my connection with the Observatory. ' Infact the observations of 1842 were sent to press on Mar. 1st, 1843. --About this year the Annual Dinner at the Visitation began to bemore important, principally under the management of Capt. W. H. Smyth, R. N. --In November I was enquiring about an 8-inch object-glass. I hadalready in mind the furnishing of our meridional instruments withgreater optical powers. --On July 14th the Admiralty referred to me aMemorial of Mr J. G. Ulrich, a chronometer maker, claiming a reward forimprovements in chronometers. I took a great deal of trouble in theinvestigation of this matter, by books, witnesses, &c. , and finallyreported on Nov. 4th that there was no ground for claim. --In April Ireceived the first application of the Royal Exchange Committee, forassistance in the construction of the Clock: this led to a great dealof correspondence, especially with Dent. --The Lunar Reductions weregoing on in full vigour. --I had much work in connection with the CapeObservatory: partly about an equatoreal required for the Observatory, but chiefly in getting Maclear's work through the press. --In this yearI began to think seriously of determining the longitude of Valencia inIreland, as a most important basis for the scale of longitude in theselatitudes, by the transmission of chronometers; and in August I wentto Valencia and examined the localities. In September I submitted aplan to the Admiralty, but it was deferred. --The new Commission forrestoring the Standards was appointed on June 20th, I being Chairman. The work of collecting standards and arranging plans was going on; MrBaily attending to Standards of Length, and Prof. W. H. Miller toStandards of Weight. We held two meetings. --A small assistance wasrendered to me by Mr Charles May (of the firm of Ransomes and May), which has contributed much to the good order of papers in theObservatory. Mr Robert Ransome had remarked my method of punchingholes in the paper by a hand-punch, the places of the holes beingguided by holes in a piece of card, and said that they could furnishme with something better. Accordingly, on Aug. 28th Mr May sent me thepunching machine, the prototype of all now used in the Observatory. "On Sept. 25th was made my proposal for an Altazimuth Instrument formaking observations of the Moon's place more frequently and throughparts of her orbit where she could never be observed with meridionalinstruments; the most important addition to the Observatory since itsfoundation. The Board of Visitors recommended it to the Admiralty, and the Admiralty sanctioned the construction of the instrument andthe building to contain it. " The following passage is quoted from theAddress of the Astronomer Royal to the Board of Visitors at theSpecial Meeting of Nov. 10th, 1843: "The most important object in theinstitution and maintenance of the Royal Observatory has always beenthe Observations of the Moon. In this term I include the determinationof the places of fixed stars which are necessary for ascertaining theinstrumental errors applicable to the instrumental observations of theMoon. These, as regards the objects of the institution, were merelyauxiliaries: the history of the circumstances which led the Governmentof the day to supply the funds for the construction of the Observatoryshews that, but for the demands of accurate Lunar Determinations asaids to navigation, the erection of a National Observatory would neverhave been thought of. And this object has been steadily kept in viewwhen others (necessary as fundamental auxiliaries) were passedby. Thus, during the latter part of Bradley's time, and Bliss's time(which two periods are the least efficient in the modern history ofthe Observatory), and during the latter part of Maskelyne's presidency(when, for years together, there is scarcely a single observation ofthe declination of a star), the Observations of the Moon were kept upwith the utmost regularity. And the effect of this regularity, asregards its peculiar object, has been most honourable to theinstitution. The existing Theories and Tables of the Moon are foundedentirely upon the Greenwich Observations; the Observatory of Greenwichhas been looked to as that from which alone adequate observations canbe expected, and from which they will not be expected in vain: and itis not perhaps venturing too much to predict that, unless some grossdereliction of duty by the managers of the Observatory should occur, the Lunar Tables will always be founded on Greenwich Observations. With this impression it has long been to me a matter ofconsideration whether means should not be taken for rendering theseries of Observations of the Moon more complete than it can be madeby the means at present recognized in our observatories. "--Inillustration of the foregoing remarks, the original inscription stillremaining on the outside of the wall of the Octagon Room of theObservatory may be quoted. It runs thus: 'Carolus II's Rex OptimusAstronomiae et Nauticae Artis Patronus Maximus Speculam hanc inutriusque commodum fecit Anno D'ni MDCLXXVI Regni sui XXVIII curanteIona Moore milite RTSG. ' "The Ashburton Treaty had been settled with the United States, for theboundary between Canada and the State of Maine, and one of itsconditions was, that a straight line about 65 miles in length shouldbe drawn through dense woods, connecting definite points. It soonappeared that this could scarcely be done except by astronomicaloperations. Lord Canning, Under Secretary of the Foreign Office, requested me to nominate two astronomers to undertake the work. Istrongly recommended that Military Officers should carry out the work, and Capt. Robinson and Lieut. Pipon were detached for this service. OnMar. 1st they took lodgings at Greenwich, and worked at theObservatory every day and night through the month. My detailedastronomical instructions to them were drawn out on Mar. 29th. Iprepared all the necessary skeleton forms, &c. , and looked to theirscientific equipment in every way. The result will be given in 1844. "Of private history: In January I went to Dover with my wife to seethe blasting of a cliff there: we also visited Sir J. Herschel atHawkhurst. In April I was at Playford, on a visit to ArthurBiddell. On Apr. 9th my daughter Annot was born. From July 22nd toAugust 25th I was travelling in the South of Ireland, chiefly to seeValencia and consider the question of determining its longitude:during this journey I visited Lord Rosse at Birr Castle, and returnedto Weymouth, where my family were staying at the time. In October Ivisited Cambridge, and in December I was again at Playford. " The journey to Cambridge (Oct. 24th to 27th) was apparently in orderto be present on the occasion of the Queen's visit there on the 25th:the following letter relating to it was written to his wife: SEDGWICK'S ROOMS, TRINITY COLLEGE, CAMBRIDGE. _1843, Oct. 26, Thursday_. I have this morning received your letter: I had no time to writeyesterday. There are more things to tell of than I can possiblyremember. The Dean of Ely yesterday was in a most ludicrous state ofmisery because his servant had sent his portmanteau (containing hisscarlet academicals as well as everything else) to London, and it wentto Watford before it was recovered: but he got it in time to shewhimself to-day. Yesterday morning I came early to breakfast withSedgwick. Then I walked about the streets to look at theflags. Cambridge never had such an appearance before. In looking alongTrinity Street or Trumpington Street there were arches and flags asclose as they could stand, and a cord stretched from King's Entranceto Mr Deck's or the next house with flags on all its length: a flag onSt Mary's, and a huge royal standard ready to hoist on TrinityGateway: laurels without end. I applied at the Registrar's office fora ticket which was to admit me to Trinity Court, the Senate House, &c. , and received from Peacock one for King's Chapel. Then there wasan infinity of standing about, and very much I was fatigued, till Igot some luncheon at Blakesley's rooms at 1 o'clock. This wasnecessary because there was to be no dinner in hall on account of theAddress presentation. The Queen was expected at 2, and arrived about10 minutes after 2. When she drove up to Trinity Gate, theVice-Chancellor, masters, and beadles went to meet her, and thebeadles laid down their staves, which she desired them to takeagain. Then she came towards the Lodge as far as the Sundial, whereWhewell as master took the college keys (a bundle of rusty keys tiedtogether by a particularly greasy strap) from the bursar Martin, andhanded them to the Queen, who returned them. Then she drove round bythe turret-corner of the court to the Lodge door. Almost every memberof the University was in the court, and there was a great hurraingexcept when the ceremonies were going forward. Presently the Queenappeared at a window and bowed, and was loudly cheered. Then noticewas given that the Queen and Prince would receive the Addresses of theUniversity in Trinity hall, and a procession was formed, in which Ihad a good place, as I claimed rank with the Professors. A throne andcanopy were erected at the top of the hall, but the Queen did not sit, which was her own determination, because if she had sat it would havebeen proper that everybody should back out before presenting theAddress to the Prince: which operation would have suffocated at least100 people. The Queen wore a blue gown and a brown shawl with animmense quantity of gold embroidery, and a bonnet. Then it was knownthat the Queen was going to service at King's Chapel at half pastthree: so everybody went there. I saw the Queen walk up the antechapeland she looked at nothing but the roof. I was not able to see her inchapel or to see the throne erected for her with its back to theTable, which has given great offence to many people. (I should havesaid that before the Queen came I called on Dr Haviland, also onScholefield, also on the Master of Christ's. ) After this she returnedto Trinity, and took into her head to look at the chapel. The clothlaid on the pavement was not long enough and the undergraduates laiddown their gowns. Several of the undergraduate noblemen carriedcandles to illuminate Newton's statue. After this the Prince went bytorchlight to the library. Then I suppose came dinner, and then it wasmade known that at half-past nine the Queen would receive some Membersof the University. So I rigged myself up and went to the levée at theLodge and was presented in my turn; by the Vice-Chancellor as"Ex-Professor Airy, your Majesty's Astronomer Royal. " The Queen andthe Prince stood together, and a bow was made to and received fromeach. The Prince recognised me and said "I am glad to see you, " orsomething like that. Next to him stood Goulburn, and next LordLyndhurst, who to my great surprise spoke very civilly to me (as Iwill tell you afterwards). The Queen had her head bare and a sort ofFrench white gown and looked very well. She had the ribbon of theGarter on her breast; but like a ninny I forgot to look whether shehad the Garter upon her arm. The Prince wore his Garter. I went to beddead tired and got up with a headache. --About the degree to the Princeand the other movements I will write again. * * * * * Here is a note from Cubitt relating to the blasting of the Round DownCliff at Dover referred to above: GREAT GEORGE STREET, _Jan. 20th, 1843_. MY DEAR SIR, _Thursday_ next the 26th at 12 is the time fixed for the attempt toblow out the foot of the "Round Down" Cliff near Dover. The Galvanic apparatus has been repeatedly tried in place--that is byexploding cartridges in the very chambers of the rock prepared for thepowder--with the batteries at 1200 feet distance they are in full formand act admirably so that I see but little fear of failure on thathead. They have been rehearsing the explosions on the plan I most stronglyrecommended, that is--to fire each chamber by an independent batteryand circuit and to discharge the three batteries simultaneously bysignal or word of command which answers well and "no mistake. " I shall write to Sir John Herschel to-day, and remain My dear Sir, Very truly yours, W. CUBITT. G. B. Airy, Esq. * * * * * The following extracts are from letters to his wife written in Irelandwhen on his journey to consider the determination of the longitude ofValencia. SKIBBEREEN, _1843, July 28_. By the bye, to shew the quiet of Ireland now, I saw in a newspaper atCork this account. At some place through which a repeal-associationwas to pass (I forget its name) the repealers of the place set up atriumphal arch. The police pulled it down, and were pelted by therepealers, and one of the policemen was much bruised. O'Connell hasdenounced this place as a disgrace to the cause of repeal, and hasmoved in the full meeting that the inhabitants of this place be struckoff the repeal list, with no exception but that of the parish priestwho was proved to be absent. And O'Connell declares that he will notpass through this place. Now for my journey. It is a sort ofhalf-mountain country all the way, with some bogs to refresh my eyes. VALENCIA HOTEL, _1843, August 6_. It seems that my coming here has caused infinite alarm. The commonpeople do not know what to conjecture, but have some notion that the"sappers and miners" are to build a bridge to admit the charge ofcavalry into the island. An attendant of Mrs Fitzgerald expressed howstrange it was that a man looking so mild and gentle could meditatesuch things "but never fear, Maam, those that look so mild are alwaysthe worst": then she narrated how that her husband was building somestables, but that she was demanding of him "Pat, you broth of a boy, what is the use of your building stables when these people are comingto destroy everything. " I suspect that the people who saw me walkingup through the storm yesterday must have thought me the prince of thepowers of the air at least. HIBERNIAN HOTEL, TRALEE, _1843, August 7_. I sailed from Valencia to Cahersiveen town in a sail-boat up the water(not crossing at the ferry). I had accommodated my time to the wish ofthe boatman, who desired to be there in time for prayers: so that Ihad a long waiting at Cahersiveen for the mail car. In walking throughthe little town, I passed the chapel (a convent chapel) to which thepeople were going: and really the scene was very curious. The chapelappeared to be overflowing full, and the court in front of it was fullof people, some sitting on the ground, some kneeling, and someprostrate. There were also people in the street, kneeling with theirfaces towards the gate pillars, &c. It seemed to me that the priestand the chapel were of less use here than even in the continentalchurches, and I do not see why both parties should not have stopped athome. When the chapel broke up, it seemed as if the streets werecrammed with people. The turnout that even a small village in Irelandproduces is perfectly amazing. 1844 "In the course of 1843 I had put in hand the engraving of the drawingsof the Northumberland Telescope at Cambridge Observatory, and wrotethe description for letterpress. In the course of 1844 the work wascompleted, and the books were bound and distributed. "The building to receive the Altazimuth Instrument was erected in thecourse of the year; during the construction a foreman fell into thefoundation pit and broke his leg, of which accident he died. This isthe only accident that I have known at the Observatory. --TheElectrometer Mast and sliding frame were erected near the MagneticObservatory. --The six-year Catalogue of 1439 stars was finished; thiswork had been in progress during the last few years. --In May I went toWoolwich to correct the compasses of the 'Dover, ' a small iron steamercarrying mails between Dover and Ostend: this I believe was the firstiron ship possessed by the Admiralty. --The Lunar Reductions weremaking good progress; 16 computers were employed upon them. I madeapplication for printing them and the required sum (_£1000_) wasgranted by the Treasury. --In this year commenced that remarkablemovement which led to the discovery of Neptune. On Feb. 13thProf. Challis introduced Mr Adams to me by letter. On Feb. 15th I sentmy observed places of Uranus, which were wanted. On June 19th I alsosent places to Mr E. Bouvard. --As regards the National Standards, MrBaily (who undertook the comparisons relating to standards of length)died soon, and Mr Sheepshanks then undertook the work. --I attended themeeting of the British Association held at York (principally incompliment to the President, Dr Peacock), and gave an oral account ofmy work on Irish Tides. --At the Oxford Commemoration in June, thehonorary degree of D. C. L. Was conferred on M. Struve and on me, andthen a demand was made on each of us for _£6. 6s. _ for fees. We weremuch disgusted and refused to pay it, and I wrote angrily to DrWynter, the Vice-Chancellor. The fees were ultimately paid out of theUniversity Chest. "In this year the longitude of Altona was determined by M. Struve forthe Russian Government. For this purpose it was essential thatfacilities should be given for landing chronometers at Greenwich. Butthe consent of the customhouse authorities had first to be obtained, and this required a good deal of negotiation. Ultimately thedetermination was completed in the most satisfactory manner. Thechronometers, forty-two in number, crossed the German Sea sixteentimes. The transit observers were twice interchanged, in order toeliminate not only their Personal Equation, but also the gradualchange of Personal Equation. On Sept. 30th Otto Struve formally wrotehis thanks for assistance rendered. "For the determination of the longitude of Valencia, which was carriedout in this year, various methods were discussed, but the plan ofsending chronometers by mail conveyance was finally approved. FromLondon to Liverpool the chronometers were conveyed by the railways, from Liverpool to Kingstown by steamer, from Dublin to Tralee by theMail Coaches, from Tralee to Cahersiveen by car, from Cahersiveen toKnightstown by boat, and from Knightstown to the station on the hillthe box was carried like a sedan-chair. There were numerous otherarrangements, and all succeeded perfectly without a failure of anykind. Thirty pocket chronometers traversed the line between Greenwichand Kingstown about twenty-two times, and that between Kingstown andValencia twenty times. The chronometrical longitudes of LiverpoolObservatory, Kingstown Station, and Valencia Station are 12m 0. 05s, 24m 31. 17s, 41m 23. 25s; the geodetic longitudes, computed fromelements which I published long ago in the EncyclopaediaMetropolitana, are 12m 0. 34s, 24m 31. 47s, 41m 23. 06s. It appears fromthis that the elements to which I have alluded represent the form ofthe Earth here as nearly as is possible. On the whole, I think itprobable that this is the best arc of parallel that has ever beenmeasured. "With regard to the Maine Boundary: on May 7th Col. Estcourt, theBritish Commissioner, wrote to me describing the perfect success offollowing out my plan: the line of 64 miles was cut by directions laidout at the two ends, and the cuttings met within 341 feet. The countrythrough which this line was to pass is described as surpassing in itsdifficulties the conception of any European. It consists ofimpervious forests, steep ravines, and dismal swamps. A survey for theline was impossible, and a tentative process would have broken thespirit of the best men. I therefore arranged a plan of operationsfounded on a determination of the absolute latitudes and thedifference of longitudes of the two extremities. The difference oflongitudes was determined by the transfer of chronometers by the verycircuitous route from one extremity to the other; and it was necessaryto divide the whole arc into four parts, and to add a small part bymeasure and bearing. When this was finished, the azimuths of the linefor the two ends were computed, and marks were laid off for startingwith the line from both ends. One party, after cutting more thanforty-two miles through the woods, were agreeably surprised, on thebrow of a hill, at seeing directly before them a gap in the woods onthe next line of hill; it opened gradually, and proved to be the lineof the opposite party. On continuing the lines till they passedabreast of each other, their distance was found to be 341 feet. Toform an estimate of the magnitude of this error, it is to be observedthat it implies an error of only a quarter of a second of time in thedifference of longitudes; and that it is only one-third (or nearly so)of the error which would have been committed if the spheroidal form ofthe Earth had been neglected. I must point out the extraordinary meritof the officers who effected this operation. Transits were observedand chronometers were interchanged when the temperature was lower than19° below zero: and when the native assistants, though paid highly, deserted on account of the severity of the weather, the Britishofficers still continued the observations upon whose delicacyeverything depended. "Of private history: From July 3rd to Aug. 13th I was in Ireland withmy wife. This was partly a business journey in connection with thedetermination of the longitude of Valencia. On Jan. 4th I asked LordLyndhurst (Lord Chancellor) to present my brother to the living ofHelmingham, which he declined to do: but on Dec. 12th he offeredBinbrooke, which I accepted for my brother. " 1845 "A map of the Buildings and Grounds of the Observatory was commencedin 1844, and was still in progress. --On Mar. 19th I was employed on amatter which had for some time occupied my thoughts, viz. , there-arrangement of current manuscripts. I had prepared a sloping box(still in use) to hold 24 portfolios: and at this time I arrangedpapers A, and went on with B, C, &c. Very little change has been madein these. --In reference to the time given to the weekly report onMeteorology to the Registrar General, the Report to the Board ofVisitors contains the following paragraph: 'The devotion of some of myassistants' time and labour to the preparation of the MeteorologicalReport attached to the weekly report of the Registrar General, is, inmy opinion, justified by the bearing of the meteorological facts uponthe medical facts, and by the attention which I understand that Reportto have excited. '--On Dec. 13th the sleep of Astronomy was broken bythe announcement that a new planet, Astraea, was discovered by MrHencke. I immediately circulated notices. --But in this year began amore remarkable planetary discussion. On Sept. 22nd Challis wrote tome to say that Mr Adams would leave with me his results on theexplanation of the irregularities of Uranus by the action of anexterior planet. In October Adams called, in my absence. On Nov. 5th Iwrote to him, enquiring whether his theory explained the irregularityof radius-vector (as well as that of longitude). I waited for ananswer, but received none. (See the Papers printed in the RoyalAstronomical Society's Memoirs and Monthly Notices). --In the RoyalSociety, the Royal Medal was awarded to me for my Paper on the IrishTides. --In the Royal Astronomical Society I was President; and, with aspeech, delivered the Medal to Capt. Smyth for the Bedford Catalogueof Double Stars. --On Jan. 21st I was appointed (with Schumacher) oneof the Referees for the King of Denmark's Comet Medal: I have theKing's Warrant under his sign manual. --The Tidal Harbour Commissioncommenced on Apr. 5th: on July 21st my Report on Wexford Harbour (inwhich I think I introduced important principles) was communicated. OneReport was made this year to the Government. --In the matter of SawMills (which had begun in 1842), I had prepared a second set of plansin 1844, and in this year Mr Nasmyth made a very favourable report onmy plan. A machinist of the Chatham Dock Yard, Sylvester, was set towork (but not under my immediate command) to make a model: and thisproduced so much delay as ultimately to ruin the design. --On Jan. 1stI was engaged on my Paper 'On the flexure of a uniform bar, supportedby equal pressures at equidistant points. '" (This was probably inconnection with the support of Standards of Length, for theCommission. Ed. ). --In June I attended the Meeting of the BritishAssociation at Cambridge, and on the 20th I gave a Lecture onMagnetism in the Senate House. The following quotation relating tothis Lecture is taken from a letter by Whewell to his wife (see Lifeof William Whewell by Mrs Stair Douglas): "I did not go to the SenateHouse yesterday evening. Airy was the performer, and appears to haveoutdone himself in his art of giving clearness and simplicity to thehardest and most complex subjects. He kept the attention of hisaudience quite enchained for above two hours, talking aboutterrestrial magnetism. "--On Nov. 29th I gave evidence before aCommittee of the House of Commons on Dover Harbour Pier. "With respect to the Magnetical and Meteorological Establishment, thetransactions in this year were most important. It had been understoodthat the Government establishments had been sanctioned twice forthree-year periods, of which the second would expire at the end of1845: and it was a question with the scientific public whether theyshould be continued. My own opinion was in favour of stopping theobservations and carefully discussing them. And I am convinced thatthis would have been best, except for the subsequent introduction ofself-registering systems, in which I had so large a share. There wasmuch discussion and correspondence, and on June 7th the Board ofVisitors resolved that 'In the opinion of the Visitors it is of theutmost importance that these observations should continue to be madeon the most extensive scale which the interests of those sciences mayrequire. ' The meeting of the British Association was held at Cambridgein June: and one of the most important matters there was the Congressof Magnetic Philosophers, many of them foreigners. It was resolvedthat the Magnetic Observatory at Greenwich be continuedpermanently. At this meeting I proposed a resolution which has provedto be exceedingly important. I had remarked the distress which thecontinuous two-hourly observations through the night produced to myAssistants, and determined if possible to remove it. I thereforeproposed 'That it is highly desirable to encourage by specificpecuniary reward the improvement of self-recording magnetical andmeteorological apparatus: and that the President of the BritishAssociation and the President of the Royal Society be requested tosolicit the favourable consideration of Her Majesty's Government tothis subject, ' which was adopted. In October the Admiralty expressedtheir willingness to grant a reward up to _£500_. Mr Charles Brookehad written to me proposing a plan on Sept. 23rd, and he sent me hisfirst register on Nov. 24th. On Nov. 1st the Treasury informed theAdmiralty that the Magnetic Observatories will be continued for afurther period. "The Railway Gauge Commission in this year was an importantemployment. The Railways, which had begun with the Manchester andLiverpool Railway (followed by the London and Birmingham) had advancedover the country with some variation in their breadth of gauge. Thegauge of the Colchester Railway had been altered to suit that of theCambridge Railway. And finally there remained but two gauges: thebroad gauge (principally in the system allied with the Great WesternRailway); and the narrow gauge (through the rest of England). Thesecame in contact at Gloucester, and were likely to come in contact atmany other points--to the enormous inconvenience of the public. TheGovernment determined to interfere, beginning with a Commission. OnJuly 3rd Mr Laing (then on the Board of Trade) rode to Greenwich, bearing a letter of introduction from Sir John Lefevre and a requestfrom Lord Dalhousie (President of the Board of Trade) that I would actas second of a Royal Commission (Col. Sir Frederick Smith, Airy, Prof. Barlow). I assented to this: and very soon began a vigorous course ofbusiness. On July 23rd and 24th I went with Prof. Barlow and ourSecretary to Bristol, Gloucester, and Birmingham: on Dec. 17th I wenton railway experiments to Didcot: and on Dec. 29th to Jan. 2nd I wentto York, with Prof. Barlow and George Arthur Biddell, for railwayexperiments. On Nov. 21st I finished a draft Report of the RailwayGauge Commission, which served in great measure as a basis for thatadopted next year. "Of private history: I wrote to Lord Lyndhurst on Feb. 20th, requesting an exchange of the living to which he had presented mybrother in Dec. 1844 for that of Swineshead: to which heconsented. --On Jan. 29th I went with my wife on a visit to my uncleGeorge Biddell, at Bradfield St George, near Bury. --On June 9th I wentinto the mining district of Cornwall with George Arthur Biddell. --FromAug. 25th to Sept. 26th I was travelling in France with my sister andmy wife's sister, Georgiana Smith. I was well introduced, and thejourney was interesting. --On Oct. 29th my son Osmund was born. --MrF. Baily bequeathed to me _£500_, which realized _£450_. " Here are some extracts from letters written to his wife relating tothe visit to the Cornish mines, &c. -- PEARCE'S HOTEL, FALMOUTH, _1845, June 12th, Thursday_. Then we walked to the United Mines in Gwennap. The day was very fineand now it was perfectly broiling: and the hills here are long andsteep. At the United Mines we found the Captain, and he invited us tojoin in a rough dinner, to which he and the other captains were goingto sit down. Then we examined one of the great pumping engines, whichis considered the best in the country: and some other engines. Between3 and 4 there was to be a setting out of some work to the men by asort of Dutch Auction (the usual way of setting out the work here):some refuse ores were to be broken up and made marketable, and thesubject of competition was, for how little in the pound on the grossproduce the men would work them up. While we were here a man wasbrought up who was hurt in blasting: a piece of rock had fallen onhim. At this mine besides the ladder ways, they have buckets slidingin guides by which the men are brought up: and they are just preparingfor work another apparatus which they say is tried successfully atanother mine (Tresavean): there are two wooden rods _A_ and _B_reaching from the top to the bottom, moved by cranks from the samewheel, so that one goes up when the other goes down, and vice versâ:each of these rods has small stages, at such a distance that when therod _A_ is down and the rod _B_ is up, the first stage of _A_ is levelwith the first stage of _B_: but when the rod _A_ is up and the rod_B_ is down, the second stage of _A_ is level with the first stage of_B_: so a man who wants to descend steps on the first stage of _A_ andwaits till it goes down: then he steps sideways on the first stage of_B_ and waits till it goes down: then he steps sideways to the secondstage of _A_ and waits till it goes down, and so on: or if a man iscoming up he does just the same. While we were here Mr R. Taylorcame. We walked home (a long step, perhaps seven miles) in a very hotsun. Went to tea to Mr Alfred Fox, who has a house in a beautifulposition looking to the outside of Falmouth Harbour. * * * * * PENZANCE, _1845, June 14, Saturday_. Yesterday morning we breakfasted early at Falmouth, and before 9started towards Gwennap. I had ascertained on Thursday that JohnWilliams (the senior of a very wealthy and influential family in thiscountry) was probably returned from London. So we drove first to hishouse Burntcoose or Barncoose, and found him and his wife athome. (They are Quakers, the rest of the family are not. ) Sedgwick, and Whewell, and I, or some of our party including me, had slept onceat their house. They received George and me most cordially, andpressed us to come and dine with them after our visit to Tresaveanmine, of which intention I spoke in my last letter: so I named 4o'clock as hour for dinner. After a little stay we drove to Tresavean, where I found the Captain of the mine prepared to send an UndergroundCaptain and a Pit-man to descend with us. So we changed our clothesand descended by the ladders in the pumpshaft. Pretty work to descendwith the huge pump-rods (garnished with large iron bolts) workingviolently, making strokes of 12 feet, close to our elbows; and with anearly bottomless pit at the foot of every ladder, where we had toturn round the foot of the ladder walking on only a narrowboard. However we got down to the bottom of the mine with great safetyand credit, seeing all the mighty machinery on the way, to a greaterdepth than I ever reached before, namely 1900 feet. From the bottom ofthe pump we went aside a short distance into the lowest workings wheretwo men nearly naked were driving a level towards the lode or vein ofore. Here I felt a most intolerable heat: and upon moving to get outof the place, I had a dreadful feeling of feebleness and fainting, such as I never had in my life before. The men urged me to climb theladders to a level where the air was better, but they might as wellhave urged me to lift up the rock. I could do nothing but sit down andlean fainting against the rocks. This arose entirely from the badnessof the air. After a time I felt a trifle better, and then I climbedone short ladder, and sat down very faint again. When I recovered, twomen tied a rope round me, and went up the ladder before me, supportinga part of my weight, and in this way I ascended four or five ladders(with long rests between) till we came to a level, 260 fathoms belowthe adit or nearly 300 fathoms below the surface, where there was atolerable current of pretty good air. Here I speedily recovered, though I was a little weak for a short time afterwards. George alsofelt the bad air a good deal, but not so much as I. He descended tosome workings equally low in another place (towards which the partythat I spoke of were directing their works), but said that the airthere was by no means so bad. We all met at the bottom of theman-engine 260 fathoms below the adit. We sat still a little while, and I acquired sufficient strength and nerve, so that I did not feelthe slightest alarm in the operation of ascending by theman-engine. This is the funniest operation that I ever saw: it is theonly absolute novelty that I have seen since I was in the countrybefore: it has been introduced 2-1/2 years in Tresavean, and one dayin the United Mines. In my last letter I described the principle. Inthe actual use there is no other motion to be made by the person whois ascending or descending than that of stepping sideways each time(there being proper hand-holds) with no exertion at all, except thatof stepping exactly at the proper instant: and not the shadow ofunpleasant feeling in the motion. Any woman may go with the mostperfect comfort, if she will but attend to the rules of stepping, andforget that there is an open pit down to the very bottom of themine. In this way we were pumped up to the surface, and came up ascool as cucumbers, instead of being drenched with perspiration. In mydescription in last letter I forgot to mention that between the stageson the moving rods which I have there described there are intermediatestages on the moving rods (for which there is ample room, inasmuch asthe interval between the stages on each rod used by one person is 24feet), and these intermediate stages are used by persons _descending_:so that there are persons _ascending_ and persons _descending_ at thesame time, who never interfere with each other and never step on thesame stages, but merely see each other passing on the other rods--Itis a most valuable invention. We then changed our clothes and washed, and drove to Barncoose, arriving in good time for the dinner. I foundmyself much restored by some superb Sauterne with water. When we wereproposing to go on to Camborne, Mr and Mrs Williams pressed us soaffectionately to stop that we at length decided on stopping for thenight, only bargaining for an early breakfast this morning. Thismorning after breakfast, we started for Redruth and Camborne. Thepopulation between them has increased immensely since I was herebefore. &c. &c. * * * * * Here is a letter written to his wife while he was engaged on thebusiness of the Railway Gauge Commission. It contains reminiscences ofsome people who made a great figure in the railway world at that time, and was preceded by a letter which was playfully addressed "From thePalace of King Hudson, York. " GEORGE INN, YORK, _1845, Dec. 30_. I wrote yesterday from Mr Hudson's in time for the late post, and hopethat my letter might be posted by the servant to whom it wasgiven. Our affairs yesterday were simple: we reached Euston Stationproperly, found Watson there, found a carriage reserved for us, eatpork-pie at Wolverton (not so good as formerly), dined at Derby, andarrived in York at 5. 20. On the way Watson informed me that theGovernment have awarded us _£500_ each. Sir F. Smith had talked overthe matter with us, and I laid it down as a principle that weconsidered the business as an important one and one of very greatresponsibility, and that we wished either that the Government shouldtreat us handsomely or should consider us as servants of the Stateacting gratuitously, to which they assented. I think the Governmenthave done very well. Mr Hudson, as I have said, met us on the platformand pressed us to dine with him (though I had dined twice). Then wefound the rival parties quarrelling, and had to arrange betweenthem. This prevented me from writing for the early post. (I forgot tomention that Saunders, the Great Western Secretary, rode with us allthe way). At Hudson's we had really a very pleasant dinner: I satbetween Vernon Harcourt and Mrs Malcolm (his sister Georgiana) andnear to Mr Hudson. This morning we were prepared at 9 at the Stationfor some runs. Brunel and other people had arrived in the night. Andwe have been to Darlington and back, with a large party in ourexperimental train. George Arthur Biddell rode on the engine asrepresenting me. But the side wind was so dreadfully heavy that, asregards the wants of the case, this day is quite thrown away. We havesince been to lunch with Vernon Harcourt (Mrs Harcourt not at home)and then went with him to look at the Cathedral. The Chapter-house, which was a little injured, has been pretty well restored: all otherthings in good order. The Cathedral looks smaller and lower thanFrench cathedrals. Now that we have come in, the Lord Mayor of Yorkhas just called to invite us to dinner to-morrow. --I propose to GeorgeArthur Biddell that he go to Newcastle this evening, in order to seeglass works and other things there to-morrow, and to return when hecan. I think that I can persuade Barlow to stop to see the experiments out, and if so I shall endeavour to return as soon as possible. Theearliest day would be the day after to-morrow. * * * * * The following extract is from a letter written to Mr Murray forinsertion in his Handbook of France, relating to the Breakwater atCherbourg, which Airy had visited during his journey in France in theautumn of this year. ROYAL OBSERVATORY, GREENWICH, _1845, Oct. 8th_. My opinion on the construction I need not say ought not to be quoted:but you are quite welcome to found any general statement on it; orperhaps it may guide you in further enquiries. To make it clear, Imust speak rather generally upon the subject. There are three ways inwhich a breakwater may be constructed. 1. By building a strong wallwith perpendicular face from the bottom of the sea. 2. By making abank with nothing but slopes towards the sea. 3. By making a slopingbank to a certain height and then building a perpendicular wall uponit. --Now if the 1st of these constructions could be arranged, I haveno doubt that it would be the best of all, because a sea does not_break_ against a perpendicular face, but recoils in an unbrokenswell, merely making a slow quiet push at the wall, and not making aviolent impact. But practically it is nearly impossible. The 2ndconstruction makes the sea to break tremendously, but if the slopingsurface be made of square stone put together with reasonable carethere is not the smallest tendency to unseat these stones. This is theprinciple of construction of Plymouth Breakwater. In the 3rdconstruction, the slope makes the sea to break tremendously, and thenit strikes the perpendicular face with the force of a battering ram:and therefore in my opinion this is the worst construction of all. Afew face-stones may easily be dislodged, and then the sea enteringwith this enormous force will speedily destroy the whole. This is theform of the Cherbourg Digue. From this you will gather that I have a full belief that PlymouthBreakwater will last very long, and that the Digue of Cherbourg, atleast its upper wall, will not last long. The great bank will last agood while, gradually suffering degradation, but still protecting theRoad pretty well. I was assured by the officers residing on the Digue that the sea whichon breaking is thrown vertically upwards and then falls down upon thepavement does sometimes push the stones about which are lying thereand which weigh three or four tons. I saw some preparations for the foundations of the fort at the easternextremity of the Digue. One artificial stone of concrete measured12'9" × 6'7" × 5'7", and was estimated to weigh 25000 kilogrammes. CHAPTER VI. AT GREENWICH OBSERVATORY--1846 TO 1856. 1846 "On Nov. 7th I proposed a change in the form of Estimates for theObservatory. The original astronomical part was provided by theAdmiralty, and the new magnetical and meteorological part was providedby the Treasury: and the whole Estimates and Accounts of theObservatory never appeared in one public paper. I proposed that thewhole should be placed on the Navy Estimates, but the Admiraltyrefused. I repeated this in subsequent years, with no success. Meantime I always sent to the Admiralty a duplicate of myTreasury Estimate with the proper Admiralty Estimate. --Stephenson'sRailway through the lower part of the Park, in tunnel about 850 feetfrom the Observatory, was again brought forward. On Feb. 20th it wasput before me by the Government, and on March 9th I made experimentsat Kensal Green, specially on the effect of a tunnel: which I found tobe considerable in suppressing the tremors. On May 6th I made myReport, generally favourable, supposing the railway to be intunnel. On May 13th I, with Mr Stephenson, had an interview at theAdmiralty with Lord Ellenborough and Sir George Cockburn. The Earlappeared willing to relax in his scruples about allowing a railwaythrough the Park, when Sir George Cockburn made a most solemn protestagainst it, on the ground of danger to an institution of suchimportance as the Observatory. I have no doubt that this protest ofSir George Cockburn's really determined the Government. On June 10th Iwas informed that the Government refused their consent. After this theSouth Eastern Railway Company adopted the line through TranquilVale. --In consequence of the defective state of Paramatta ObservatoryI had written to Sir Robert Peel on April 16th raising the question ofa General Superintending Board for Colonial Observatories: and on June27th I saw Mr Gladstone at the Colonial Office to enquire about thepossibility of establishing local Boards. On June 29th a general planwas settled, but it never came to anything. --Forty volumes of theObservatory MSS. Were bound--an important beginning. --Deep-sunkthermometers were prepared by Prof. Forbes. --On June 22nd Sir RobertInglis procured an Order of the House of Commons for printing a paperof Sir James South's, ostensibly on the effects of a railway passingthrough Greenwich Park, but really attacking almost everything that Idid in the Observatory. I replied to this on July 21st by a letter inthe Athenaeum addressed to Sir Robert Inglis, in terms so strong andso well supported that Sir James South was effectually silenced. " Thefollowing extract from a letter of Airy's to the Earl of Rosse, datedDec. 15th 1846, will shew how pronounced the quarrel between Airy andSouth had become in consequence of the above-mentioned attack andprevious differences: "After the public exposure which his conduct inthe last summer compelled me to make, I certainly cannot meet him onequal terms, and desire not to meet him at all. " (Ed. ). --"In theMag. And Met. Department, I was constantly engaged with Mr CharlesBrooke in the preparation and mounting of the self-registeringinstruments, and the chemical arrangements for their use, to the endof the year. With Mr Ronalds I was similarly engaged: but I had thegreatest difficulty in transacting business with him, from hisunpractical habits. --The equipment of the Liverpool Observatory, underme, was still going on: I introduced the use of Siemens's ChronometricGovernor for giving horary motion to an Equatoreal there. I have sinceintroduced the same principle in the Chronograph Barrel and the GreatEquatoreal at Greenwich: I consider it important. --On Feb. 13th Ireceived the Astronomical Society's Medal for the PlanetaryReductions. --In the University of London: At this time seriously beganthe discussion whether there should be a compulsory examination inmatters bearing on religious subjects. After this there was nopeace. --For discovery of Comets three medals were awarded bySchumacher and me: one to Peters, two to De Vico. A comet was seen byHind, and by no other observer: after correspondence, principally in1848, the medal was refused to him. --With respect to the Railway GaugeCommission: On Jan. 1st, in our experiments near York, the engine ranoff the rails. On Jan. 29th the Commissioners signed the Report, andthe business was concluded by the end of April. Our recommendation wasthat the narrow gauge should be carried throughout. This was opposedmost violently by partisans of the broad gauge, and they hadsufficient influence in Parliament to prevent our recommendation frombeing carried into effect. But the policy, even of the Great WesternRailway (in which the broad gauge originated), has supported ourviews: the narrow gauge has been gradually substituted for the broad:and the broad now (1872) scarcely exists. --On June 20th Lord Canningenquired of me about makers for the clock in the Clock Tower ofWestminster Palace. I suggested Vulliamy, Dent, Whitehurst; and madeother suggestions: I had some correspondence with E. B. Denison, aboutclocks. --I had much correspondence with Stephenson about the TubularBridge over the Menai Straits. Stephenson afterwards spoke of myassistance as having much supported him in this anxious work: onDec. 11th I was requested to make a Report, and to charge a fee as aCivil Engineer; but I declined to do so. In January I went, withGeorge Arthur Biddell, to Portsmouth, to examine Lord Dundonald'srotary engine as mounted in the 'Janus, ' and made a Report on the sameto the Admiralty: and I made several subsequent Reports on the samematter. The scheme was abandoned in the course of next year; the realcause of failure, as I believe, was in the bad mounting in the ship. "The engrossing subject of this year was the discovery of Neptune. AsI have said (1845) I obtained no answer from Adams to a letter ofenquiry. Beginning with June 26th of 1846 I had correspondence of asatisfactory character with Le Verrier, who had taken up the subjectof the disturbance of Uranus, and arrived at conclusions not verydifferent from those of Adams. I wrote from Ely on July 9th toChallis, begging him, as in possession of the largest telescope inEngland, to sweep for the planet, and suggesting a plan. I receivedinformation of its recognition by Galle, when I was visiting Hansen atGotha. For further official history, see my communications to theRoyal Astronomical Society, and for private history see the papers inthe Royal Observatory. I was abused most savagely both by English andFrench. " The Report to the Visitors contains an interesting account of theGreat Lunar Reductions, from which the following passage is extracted:"Of the Third Section, containing the comparison of Observed Placeswith Tabular Places, three sheets are printed, from 1750 to 1756. Thiscomparison, it is to be observed, does not contain a simple comparisonof places, but contains also the coefficients of the various changesin the moon's place depending on changes in the elements. . . . Theprocess for the correction of the elements by means of thesecomparisons is now going on: and the extent of this work, even afterso much has been prepared, almost exceeds belief. For the longitude, ten columns are added in groups, formed in thirteen different ways, each different way having on the average about nine hundredgroups. For the ecliptic polar distance, five columns are added ingroups, formed in seven different ways, each different way having onthe average about nine hundred groups. Thus it will appear that thereare not fewer than 150, 000 additions of columns of figures. This partof the work is not only completed but is verified, so that the booksof comparison of Observed and Tabular Places are, as regards thiswork, completely cleared out. The next step is to take the means ofthese groups, a process which is now in hand: it will be followed bythe formation and solution of the equations on which the correctionsof the elements depend. " The following remarks, extracted from the Report to the Visitors, withrespect to the instrumental equipment of the Observatory, embody theviews of the Astronomer Royal at this time: "The utmost change, whichI contemplate as likely to occur in many years, in regard to ourmeridional instruments, is the substitution of instruments of the sameclass carrying telescopes of larger aperture. The only instrumentwhich, as I think, may possibly be called for by the demands of theastronomer or the astronomical public, is a telescope of the largestsize, for the observation of faint nebulae and minute doublestars. Whether the addition of such an instrument to our apparatuswould be an advantage, is, in my opinion, not free from doubt. Theline of conduct for the Observatory is sufficiently well traced; therecan be no doubt that our primary objects ought to be the accuratedetermination of places of the fundamental Stars, the Sun, thePlanets, and, above all, the Moon. Any addition whatever to our powersor our instrumental luxuries, which should tend to withdraw ourenergies from these objects, would be a misfortune to theObservatory. " Of private history: "In March I visited Prof. Sedgwick at Norwich. --OnMar. 28th the 'Sir Henry Pottinger' was launched from Fairbairn's Yardon the Isle of Dogs, where I was thrown down and dislocated my rightthumb. --From Apr. 10th to 15th I was at Playford. --On June 10th Prof. Hansen arrived, and stayed with me to July 4th. --From July 6th to 10thI was visiting Dean Peacock at Ely. --From July 23rd to 29th I was atPlayford, where for the first time I lodged in my own cottage. I hadbought it some time before, and my sister had superintendedalterations and the addition of a room. I was much pleased thus to beconnected with the happy scenes of my youth. --From Aug. 10th to Oct. 11th I was with my wife and her sister Elizabeth Smith on theContinent. We stayed for some time at Wiesbaden, as my nerves wereshaken by the work on the Railway Gauge Commission, and I wanted theWiesbaden waters. We visited various places in Germany, and made a10-days' excursion among the Swiss Mountains. At Gotha we lodged withProf. Hansen for three days; and it was while staying here that Iheard from Prof. Encke (on Sept. 29th) that Galle had discovered theexpected planet. We visited Gauss at Göttingen and Miss CarolineHerschel at Hannover. We had a very bad passage from Hamburgh toLondon, lasting five days: a crank-pin broke and had to be repaired:after four days our sea-sickness had gone off, during the gale--avaluable discovery for me, as I never afterwards fearedsea-sickness. --On Dec. 22nd I attended the celebration of the 300thanniversary of Trinity College. " * * * * * The following extracts relating to the engines of the "Janus" aretaken from letters to his wife dated from Portsmouth, Jan. 6th and7th, 1846: As soon as possible we repaired to the Dock Yard and presentedourselves to the Admiral Superintendant--Admiral Hyde Parker (not SirHyde Parker). Found that the "Janus" had not arrived: the AdmiralSuperintendant (who does not spare a hard word) expressing himselfcuriously thereon. But he had got the proper orders from the Admiraltyrelating to me: so he immediately sent for Mr Taplin, thesuperintendant of machinery: and we went off to see the small engineof Lord D--d's construction which is working some pumps and othermachinery in the yard. It was kept at work a little longer than usualfor us to see it. And I have no hesitation in saying that it wasworking extremely well. It had not been opened in any way for half ayear, and not for repair or packing for a much longer time. . . . Thismorning we went to the Dock Yard, and on entering the engine housethere was Shirreff, and Lord D--d soon appeared. The "Janus" had cometo anchor at Spithead late last night, and had entered the harbourthis morning. Blowing weather on Saturday night. We had the enginepretty well pulled to pieces, and sat contemplating her a longtime. Before this Denison had come to us. We then went on board the"Janus" with Shirreff but not with Lord D--d. The engines were stillhot, and so they were turned backwards a little for my edification. (This was convenient because, the vessel being moored by herhead, she could thus strain backwards without doing mischief. ) Thevacuum not good. Then, after a luncheon on board, it was agreed to runout a little way. But the engines absolutely stuck fast, and would notstir a bit. This I considered a perfect Godsend. So the paddle-wheels(at my desire) were lashed fast, and we are to see her openedto-morrow morning. This morning (Jan. 7th) we all went off to the "Janus, " where weexpected to find the end of the cylinder (where we believe yesterday'sblock to have taken place) withdrawn. But it was not near it. After agreat many bolts were drawn, it was discovered that one bolt could notbe drawn, and in order to get room for working at it, it was necessaryto take off the end of the other cylinder. And such a job! Threepulley hooks were broken in my sight, and I believe some out of mysight. However this auxiliary end was at last got off: and the peoplebegan to act on the refractory bolt. But by this time it was gettingdark and the men were leaving the dockyard, so I left, arranging thatwhat they could do in preparation for me might be done in good timeto-morrow morning. 1847 "On Nov. 13th I circulated an Address, proposing to discontinue theuse of the Zenith Tube, because it had been found by a long course ofcomparative trials that the Zenith Tube was not more accurate than theMural Circle. The Address stated that 'This want of superiorefficiency of the Zenith Tube (which, considered in reference to theexpectations that had been formed of its accuracy, must be estimatedas a positive failure) is probably due to two circumstances. One is, the use of a plumb-line; which appears to be affected with variousill-understood causes of unsteadiness. The other is, the insuperabledifficulty of ventilating the room in which the instrument ismounted. '--On December 20th I circulated an Address, proposing aTransit Circle, with telescope of 8 inches aperture. The Addressstates as follows: 'The clear aperture of the Object-Glass of ourTransit Instrument is very nearly 5 inches, that of our Mural Circleis very nearly 4 inches. '--I had been requested by the Master-Generalof Ordnance (I think) to examine Candidates for a Mastership inWoolwich Academy, and I was employed on it in February and March, inconjunction with Prof. Christie. --In January I applied to LordAuckland for money-assistance to make an astronomical journey on theContinent, but he refused. --On Mar. 19th Sir James South addressed tothe Admiralty a formal complaint against me for not observing with theastronomical instruments: on Mar. 31st I was triumphantly acquitted bythe Admiralty. --In June I was requested by the Commissioners ofRailways to act as President of a Commission on Iron Bridges(suggested by the fall of the bridge at Chester). Lord Aucklandobjected to it, and I was not sorry to be spared the trouble ofit. --In December I was requested, and undertook to prepare theAstronomical part of the Scientific Manual for Naval Officers. --OnSept. 24th occurred a very remarkable Magnetic Storm, to which therehad been nothing comparable before. Mr Glaisher had it observed by eyeextremely well, and I printed and circulated a paper concerningit. --Hansen, stimulated by the Lunar Reductions, discovered two longinequalities in the motion of the Moon, produced by the action ofVenus. In the Report to the Visitors this matter is thus referred to:'In the last summer I had the pleasure of visiting Prof. Hansen atGotha, and I was so fortunate as to exhibit to him the corrections ofthe elements from these Reductions, and strongly to call his attentionto their certainty, the peculiarity of their fluctuations, and thenecessity of seeking for some physical explanation. I have muchpleasure in indulging in the thought, that it was mainly owing to thisrepresentation that Prof. Hansen undertook that quest, which hasterminated in the discovery of his two new lunar inequalities, themost remarkable discovery, I think, in Physical Astronomy. '--Indiscussing points relating to the discovery of Neptune, I made anunfortunate blunder. In a paper hastily sent to the Athenaeum(Feb. 18th) I said that Arago's conduct had been indelicate. Iperceived instantly that I had used a wrong expression, and by thevery next post I sent an altered expression. This altered expressionwas not received in time, and the original expression was printed, tomy great sorrow. I could not then apologize. But at what appeared tobe the first opportunity, in December, I did apologize; and my apologywas accepted. But I think that Arago was never again so cordial asbefore. --On July 4th Hebe was discovered. After this Iris andFlora. Now commenced that train of discoveries which has added morethan 100 planets to the Solar System. --On Oct. 8th was an AnnularEclipse of the Sun, of which the limit of annularity passed near toGreenwich. To determine the exact place, I equipped observatories atHayes, Lewisham South End, Lewisham Village, Blackwall, Stratford, Walthamstow, and Chingford. The weather was bad and no observation wasobtained. --In the Royal Astronomical Society: In 1846, the disputebetween the partisans of Adams and Le Verrier was so violent that nomedal could be awarded to either. In 1847 I (with other Fellows of theSociety) promoted a special Meeting for considering such amodification of the bye-laws that for this occasion only it might bepermissible to give two medals. After two days' stormy discussion, itwas rejected. --In the University of London: At a meeting in July, where the religious question was discussed, it was proposed to receivesome testimonial from affiliated bodies, or to consider that or someother plan for introducing religious literature. As the propriety ofthis was doubtful, there was a general feeling for taking legaladvice: and it was set aside solely on purpose to raise the questionabout legal consultation. _That_ was negatived by vote: and I thenclaimed the consideration of the question which we had put aside forit. By the influence of H. Warburton, M. P. , this was denied. I wrote aletter to be laid before the Meeting on July 28th, when I wasnecessarily absent, urging my claim: my letter was put aside. Idetermined never to sit with Warburton again: on Aug. 2nd I intimatedto Lord Burlington my wish to retire, and on Aug. 29th he transmittedto the Home Secretary my resignation. He (Lord Burlington) fullyexpressed his opinion that my claim ought to have been allowed. --OnJune 9th, on the occasion of Prince Albert's state visit to Cambridge, knighthood was offered to me through his Secretary, Prof. Sedgwick, but I declined it. --In September, the Russian Order of St Stanislaswas offered to me, Mr De Berg, the Secretary of Embassy, coming toGreenwich personally to announce it: but I was compelled by ourGovernment Rules to decline it. --I invited Le Verrier to England, andescorted him to the Meeting of the British Association at Oxford inJune. --As regards the Westminster Clock on the Parliamentary Building:in May I examined and reported on Dent's and Whitehurst's clockfactories. Vulliamy was excessively angry with me. On May 31st a greatParliamentary Paper was prepared in return to an Order of the House ofLords for correspondence relating to the Clock. --With respect to theSaw Mills for Ship Timber: work was going on under the direction ofSylvester to Mar. 18th. It was, I believe, at that time, that thefire occurred in Chatham Dock Yard which burnt the whole of thesaw-machinery. I was tired of my machinery: and, from the extendinguse of iron ships, the probable value of it was much diminished; and Imade no effort to restore it. " Of private history: "In February I went to Derby to see Whitehurst'sclock factory; and went on with my wife to Brampton near Chesterfield, where her mother was living. --From Apr. 1st to 5th I was atPlayford. --On Holy Thursday, I walked the Parish Bounds (of Greenwich)with the Parish officers and others. From Apr. 19th to 24th I was atBirmingham (on a visit to Guest, my former pupil, and afterwardsMaster of Caius College) and its neighbourhood, with George ArthurBiddell. --From June 23rd to 28th I was at Oxford and Malvern: mysister was at Malvern, for water-cure: the meeting of the BritishAssociation was at Oxford and I escorted Le Verrier thither. --July28th to 30th I was at Brampton. --From August 10th to September 18th Iwas engaged on an expedition to St Petersburg, chiefly with the objectof inspecting the Pulkowa Observatory. I went by Hamburg to Altona, where I met Struve, and started with him in an open waggon for Lübeck, where we arrived on Aug. 14th. We proceeded by steamer to Cronstadtand Petersburg, and so to Pulkowa, where I lodged with O. Struve. Iwas here engaged till Sept. 4th, in the Observatory, in expeditions inthe neighbourhood and at St Petersburg, and at dinner-parties, &c. Imet Count Colloredo, Count Ouvaroff, Count Stroganoff, Lord Bloomfield(British Ambassador), and others. On Sept. 4th I went in a smallsteamer to Cronstadt, and then in the Vladimir to Swinemünde: we werethen towed in a passage boat to Stettin, and I proceeded by railway toBerlin. On Sept. 9th I found Galle and saw the Observatory. OnSept. 10th I went to Potzdam and saw Humboldt. On the 12th I went toHamburg and lodged with Schumacher: I here visited Repsold andRümker. On Sept. 14th I embarked in the John Bull for London, andarrived there on the evening of the 18th: on the 16th it was blowing'a whole gale, ' reported to be the heaviest gale known for so manyhours; 4 bullocks and 24 sheep were thrown overboard. --From Dec. 3rdto 8th I was at Cambridge, and from the 22nd to 31st at Playford. " * * * * * Here is a letter to his wife written from Birmingham, containing anote of the progress of the ironwork for the Menai Bridge: EDGBASTON, BIRMINGHAM, _1847, Apr. 22_. Yesterday morning we started between 10 and 11 for Stourbridge, firstto see some clay which is celebrated all over the world as the onlyclay which is fit to make pots for melting glass, &c. You know that inall these fiery regions, fire-clay is a thing of very greatimportance, as no furnace will stand if made of any ordinary bricks(and even with the fire-clay, the small furnaces are examined everyweek), but this Stourbridge clay is as superior to fire-clay asfire-clay is to common brick-earth. Then we went to Fosters' puddlingand rolling works near Stourbridge. These are on a very large scale:of course much that we saw was a repetition of what we had seenbefore, but there were slitting mills, machines for rolling thepuddled blooms instead of hammering them, &c. , and we had thesatisfaction of handling the puddling irons ourselves. Then we went toanother work of the Fosters not far from Dudley, where part of thework of the Tube Bridge for the Menai is going on. The Fosters are, Ibelieve, the largest iron masters in the country, and the twoprincipal partners, the elder Mr Foster and his Nephew, accompanied usin all our inspections and steppings from one set of works to another. The length of Tube Bridge which they have in hand here is only 120feet, about 1/4 of the whole length: and at present they are only busyon the bottom part of it: but it is a prodigious thing. I shall beanxious about it. Then we went to other works of the Fosters' atKing's Wynford, where they have blast furnaces: and here after seeingall other usual things we saw the furnaces tapped. In this districtthe Fosters work the 10-yard coal in a way different from any bodyelse: they work out the upper half of its thickness and then leave theground to fall in: after a year or two this ground becomes so hard asto make a good safe roof, and then they work away the other half: thusthey avoid much of the danger and difficulty of working the thick bedall at once. The ventilation of these mines scarcely ever requiresfires, and then only what they call "lamps, " those little fire-placeswhich are used for giving light at night. (In the Northumberland andDurham pits, they constantly have immense roaring fires to make adraught. ) Then we came home through Dudley. * * * * * During his stay in Russia, there was a great desire manifested by theastronomers and scientific men of Russia that he should be presentedto the Emperor. This would no doubt have taken place had not themovements of the Court and his own want of time prevented it. Thefollowing letter to the British Ambassador, Lord Bloomfield, relatesto this matter: PULKOWA, _1847, August 25th_. _Wednesday evening_. MY LORD, I had the honour yesterday to receive your Lordship's note of Sundaylast, which by some irregularity in the communications with this placereached me, I believe, later than it ought. From this circumstance, and also from my being made acquainted only this afternoon with someofficial arrangements, I am compelled to trouble you at a time which Ifear is less convenient than I could have desired. The object of my present communication is, to ask whether (if themovements of the Court permit it) it would be agreeable to yourLordship to present me to the Emperor. In explanation of this enquiry, I beg leave to state that this is an honour to which, personally, Icould not think of aspiring. My presence however at Pulkowa at thistime is in an official character. As Astronomer Royal of England, Ihave thought it my duty to make myself perfectly acquainted with theObservatory of Pulkowa, and this is the sole object of my journey toRussia. It is understood that the Emperor takes great interest in thereputation of the Observatory, and I am confident that the remarksupon it which I am able to make would be agreeable to him. I place these reasons before you, awaiting entirely Your Lordship'sdecision on the propriety of the step to which I have alluded. I amto leave St Petersburg on Saturday the 4th of September. I have the honor to be My Lord, Your Lordship's very faithful servant, G. B. AIRY. _Lord Bloomfield, &c. , &c. _ * * * * * It was probably in acknowledgment of this letter that in due time hereceived the following letter with the offer of the Russian Order ofSt Stanislas: MONSIEUR L'ASTRONOME ROYAL, Sa Majesté l'Empereur en appréciant les travaux assidus qui vous ontdonné une place distinguée au rang des plus illustres Astronomes del'Europe, et la coopération bienveillante, que vous n'avez cessé detémoigner aux Astronomes Russes dans les expéditions, dont ils étaientchargés, et en dernier lieu par votre visite à l'Observatoire centralde Poulkova, a daigné sur mon rapport, vous nommer Chevalier de laseconde classe de l'Ordre Impérial et Royal de St Stanislas. Je nemanquerai pas de vous faire parvenir par l'entremise de LordBloomfield les insignes et la patente de l'ordre. Veuillez en attendant, Monsieur, recevoir mes sincères félicitationset l'assurance de ma parfaite considération. Le Ministre de l'instruction publique, CTE OUVAROFF. ST PÉTERSBOURG, _ce_ 24 _Août_, 1847 ---------- 5 _Septbr. _ _à Mr G. B. Airy, Esq. , Astronome Royal de S. M. Britannique à Greenwich_. * * * * * Airy provisionally accepted the Order, but wrote at once to Lord JohnRussell the following letter of enquiry: ROYAL OBSERVATORY, GREENWICH, _1847, Oct. 15_. MY LORD, In respect of the office of Astronomer Royal, I refer to the firstLord of the Treasury as Official Patron. In virtue of this relation Ihave the honour to lay before your Lordship the following statement, and to solicit your instructions thereon. For conducting with efficiency and with credit to the nation theinstitution which is entrusted to me, I have judged it proper tocultivate intimate relations with the principal Observatories ofEurope, and in particular with the great Observatory founded by theEmperor of Russia at Pulkowa near St Petersburg. I have several timesreceived Mr Struve, the Director of that Observatory, at Greenwich:and in the past summer I made a journey to St Petersburg for thepurpose of seeing the Observatory of Pulkowa. Since my return from Russia, I have received a communication fromCount Ouvaroff, Minister of Public Instruction in the Russian Empire, informing me that the Emperor of Russia desires to confer on me thedecoration of Knight Commander in the second rank of the Order of StStanislas. And I have the honour now to enquire of your Lordship whether it ispermitted to me to accept from the Emperor of Russia this decoration. I have the honour to be, My Lord, Your Lordship's very obedient servant, G. B. AIRY. _The Rt Honble Lord John Russell, &c. &c. &c. First Lord of the Treasury_. * * * * * The answer was as follows: DOWNING STREET, _October 19, 1847_. SIR, I am desired by Lord John Russell to acknowledge the receipt of yourletter, of the 14th inst. And to transmit to you the enclosed paperrespecting Foreign Orders by which you will perceive that it would becontrary to the regulations to grant you the permission you desire. I am, Sir, Your obedient servant, C. A. GREY. _G. B. Airy, Esq_. * * * * * The passage in the Regulations referred to above is quoted in thefollowing letter to Count Ouvaroff: ROYAL OBSERVATORY, GREENWICH, _1847, Oct. 22_. SIR, Referring to your Excellency's letter of the 24 August/5 September, and to my answer of the 25th September, in which I expressed my senseof the high honor conferred on me by His Majesty the Emperor of Russiain offering me, through your Excellency, the Order of St Stanislas, and my pride in accepting it:--I beg leave further to acquaint youthat I have thought it necessary to make enquiry of Lord John Russell, First Lord of Her Majesty's Treasury, as to my competency to acceptthis decoration from His Majesty the Emperor of Russia: and that hisLordship in reply has referred me to the following Regulation of theBritish Court; "5th. That no Subject of Her Majesty could be allowed to accept theInsignia of a Foreign Order from any Sovereign of a Foreign State, except they shall be so conferred in consequence of active anddistinguished services before the Enemy, either at Sea, or in theField; or unless he shall have been actually employed in the Serviceof the Foreign Sovereign. " In consequence of the stringency of this Regulation, it is my duty nowto state to your Excellency that I am unable to accept the decorationwhich His Majesty the Emperor of Russia was pleased, through yourExcellency, to offer to me. I beg leave to repeat the expression of my profound reverence to HisMajesty and of my deep sense of the honor which he has done me. I have the honor to be, Sir, Your Excellency's very faithful and obedient servant, G. B. AIRY. _To His Excellency Count Ouvaroff, &c. &c. _ In the course of the following year a very handsome gold medal, specially struck, was transmitted by Count Ouvaroff on the part of theEmperor of Russia, to Mr Airy. 1848 "In April I received authority to purchase of Simms an 8-inchobject-glass for the new Transit Circle for _£300_. The glass wastested and found satisfactory. While at Playford in January I drew thefirst plans of the Transit Circle: and C. May sketched someparts. Definite plans were soon sent to Ransomes and May, and to Simmsin March. The instrument and the building were proceeded with duringthe year. The New Transit Circle was to be erected in the CircleRoom, and considerable arrangement was necessary for continuing theCircle Observations with the existing instruments, whilst the newinstrument was under erection. When the new Transit is completelymounted, the old Transit Instrument may be removed, and the TransitRoom will be free for any other purpose. I propose to take it asPrivate Room for the Astronomer Royal. --On May 12th I made my firstproposal of the Reflex Zenith Tube. The principle of it is as follows:Let the micrometer be placed close to the object-glass, the frame ofthe micrometer being firmly connected with the object-glass cell, anda reflecting eye-piece being used with no material tube passing overthe object-glass: and let a basin of quicksilver be placed below theobject-glass, but in no mechanical connection with it, at a distanceequal to half the focal length of the object-glass. Such aninstrument would at least be free from all uncertainties of twist ofplumb-line, viscosity of water, attachment of upper plumb-linemicroscope, attachment of lower plumb-line microscope, and theobservations connected with them: and might be expected, as a resultof this extreme simplicity, to give accurate results. --A considerableerror was discovered in the graduation of Troughton's Circle, amounting in one part to six seconds, which is referred to as follows:'This instance has strongly confirmed me in an opinion which I havelong held--that no independent division is comparable in generalaccuracy to engine-division, --where the fundamental divisions of theengine have been made by Troughton's method, and where in any case thedetermination by the astronomer of errors of a few divisions willsuffice, in consequence of the uniformity of law of error, to give theerrors of the intermediate divisions. '--The method of observing withthe Altazimuth is carefully described, and the effect of it, inincreasing the number of observations of the Moon, is thus given forthe thirteen lunations between 1847, May 15, and 1848, May 30. 'Numberof days of complete observations with the Meridional Instruments, 111;number of days of complete observations with Altitude and AzimuthInstrument, 203. The results of the observations appear very good;perhaps a little, and but a little, inferior to those of theMeridional Instruments. I consider that the object for which thisinstrument was erected is successfully attained. '--Being satisfiedwith the general efficiency of the system arranged by Mr Brooke forour photographic records (of magnetical observations) I wrote to theAdmiralty in his favour, and on Aug. 25th the Admiralty ordered thepayment of _£500_ to him. A Committee of the Royal Society alsorecommended a reward of _£250_ to Mr Ronalds, which I believe was paidto him. --On May 1st the last revise of the Lunar Reductions waspassed, and on May 5th, 500 copies were sent for binding. --In thisyear Schumacher and I refused a medal to Miss Mitchell for a Cometdiscovered, because the rules of correspondence had not been strictlyfollowed: the King of Denmark gave one by special favour. --In thisyear occurred the discovery of Saturn's 8th Satellite by Mr Lassell:upon which I have various correspondence. --On the 18th of December thedegree of LL. D. Was conferred upon me by the University ofEdinburgh. --The Ipswich Lectures: A wish had been expressed that Iwould give a series of Astronomical Lectures to the people ofIpswich. I therefore arranged with great care the necessary apparatus, and lectured six evenings in a room (I forget its name--it might beTemperance Hall--high above St Matthew's Street), from Mar. 13th tothe end of the week. A shorthand writer took them down: and theseformed the 'Ipswich Lectures, ' which were afterwards published by theIpswich Museum (for whose benefit the lectures were given) and bymyself, in several editions, and afterwards by Messrs Macmillan inrepeated editions under the title of 'Airy's Popular Astronomy. '--Ithad been found necessary to include under one body all the unconnectedCommissions of Sewers for the Metropolis, and Lord Morpeth requestedme to be a member. Its operations began on Oct. 28th. In constitutionit was the most foolish that I ever knew: consisting of, I think, some200 persons, who could not possibly attend to it. It came to an end inthe next year. " Of private history: "I was at Playford from Jan. 1st to 11th, andagain from Jan. 17th to 25th: also at Playford from June 21st to July12th. --From Aug. 23rd to Sept. 12th I was in Ireland on a visit toLord Rosse at Parsonstown, chiefly engaged on trials of his largetelescope. I returned by Liverpool, where I inspected the LiverpoolEquatoreal and Clockwork, and examined Mr Lassell's telescopes andgrinding apparatus. --From Dec. 6th to 20th I was at Edinburgh with mywife, on a visit to Prof. J. D. Forbes. We made various excursions, and I attended lectures by Prof. Wilson and Sir W. Hamilton: on the18th I gave a lecture in Prof. Forbes's room. I received the HonoraryDegree of LL. D. , and made a statement on the Telescopes of Lord Rosseand Mr Lassell to the Royal Society of Edinburgh. Returned toGreenwich by Brampton. " * * * * * Here is a reminiscence of the "Ipswich Lectures, " in a letter to hiswife, dated Playford, 1848 Mar. 14, "At the proper time I went to thehall: found a chairman installed (Mr Western): was presented to him, and by him presented to the audience: made my bow and commenced. Theroom was quite full: I have rarely seen such a sea of faces; about 700I believe. Everything went off extremely well, except that the rollersof the moving piece of sky would squeak: but people did not mind it:and when first a star passed the meridian, then Jupiter, then somestars, and then Saturn, he was much applauded. Before beginning I gavenotice that I should wait to answer questions: and as soon as thelecture was finished the Chairman repeated this and begged people toask. So several people did ask very pertinent questions (from thebenches) shewing that they had attended well. Others came up andasked questions. " * * * * * The following extracts are from letters written to his wife while onhis visit to Lord Rosse at Parsonstown in Ireland. On the way hestopped at Bangor and looked at the Tubular Bridge Works, which arethus referred to: "Stopped at Bangor, settled _pro tem_. At theCastle, and then walked past the Suspension Bridge towards the TubeWorks, which are about 1-1/2 mile south-west of the Suspension Bridge. The way was by a path through fields near the water side: and from oneor two points in this, the appearance of the Suspension Bridge wasmost majestic. The Tube Bridge consists of four spans, two over waterand two over sloping land. The parts for the double tube over thewater spans (four lengths of tube) are building on a platform as atConway, to be floated by barges as there: the parts over the slopingbanks are to be built in their place, on an immense scaffolding. Isuspect that, in regard to these parts, Stephenson is sacrificing agreat deal of money to uniformity of plan: and that it would have beenmuch cheaper to build out stone arches to the piers touching thewater. . . . The Tube Works are evidently the grand promenade of theidlers about Bangor: I saw many scores of ladies and gentlemen walkingthat way with their baskets of provision, evidently going to gipsy inthe fields close by. " THE CASTLE, PARSONSTOWN, _1848, Aug. 29_. After tea it was voted that the night was likely to be fine, so we allturned out. The night was uncertain: sometimes entirely clouded, sometimes partially, but objects were pretty well seen when the skywas clear: the latter part was much steadier. From the interruption byclouds, the slowness of finding with and managing a large instrument(especially as their finding apparatus is not perfectly arranged) andthe desire of looking well at an object when we had got it, we did notlook at many objects. The principal were, Saturn and the AnnularNebula of Lyra with the 3-feet; Saturn, a remarkable cluster of stars, and a remarkable planetary nebula, with the 6-feet. With the largetelescope, the evidence of the quantity of light is prodigious. Andthe light of an object is seen in the field without any colour or anyspreading of stray light: and it is easy to see that the vision with areflecting telescope may be much more perfect than with arefractor. With these large apertures, the rings round the stars areinsensible. The planetary nebula looked a mass of living and intenselybrilliant light: this is an object which I do not suppose can be seenat all in our ordinary telescopes. The definition of the stars nearthe zenith is extremely good: with a high power (as 800) they arepoints or very nearly so--indeed I believe quite so--so that it isclear that the whole light from the great 6-feet mirror is collectedinto a space not bigger than the point of a needle. But in otherpositions of the telescope the definition is not good: and we mustlook to-day to see what is the cause of this fault. It is not a faultin the telescope, properly so-called, but it is either a tilt of themirror, or an edge-pressure upon the mirror when the telescope pointslower down which distorts its figure, or something of that kind. So Icould not see Saturn at all well, for which I was sorry, as I could sowell have compared his appearance with what I have seen before. Ishall be very much pleased if we can make out what is the fault ofadjustment, and so correct it as to get good images everywhere. It isevident that the figuring of the mirror, the polishing, and thegeneral arrangement, are perfectly managed. THE CASTLE, PARSONSTOWN, _1848, Aug. 30_. Yesterday we were employed entirely about the Great Telescope, beginning rather late. The principal objects had relation to the faultof definition when the telescope is pointed low (which I had remarkedon the preceding night), and were, to make ourselves acquainted withthe mechanism of the mirror's mounting generally, and to measure invarious ways whether the mirror actually does shift its place when thetelescope is set to different angles of elevation. For the latter wefound that the mirror actually does tilt 1/4 of an inch when the tubepoints low. This of itself will not account for the fault but itindicates that the lower part is held fast in a way that may cause astrain which would produce the fault. These operations and reasoningstook a good deal of time. Lord Rosse is disposed to make an alterationin the mounting for the purpose of correcting this possible strain. THE CASTLE, PARSONSTOWN, _1848, Aug. 31_. The weather here is still vexatious: but not absolutely repulsive. Yesterday morning Lord Rosse arranged a new method of suspending thegreat mirror, so as to take its edgewise pressure in a manner thatallowed the springy supports of its flat back to act. This employedhis workmen all day, so that the proposed finish of polishing the newmirror could not go on. I took one Camera Lucida sketch of theinstrument in the morning, dodging the heavy showers as well as Icould; then, as the afternoon was extremely fine, I took another, withmy head almost roasted by the sun. This last view is extremely prettyand characteristic, embracing parts of the mounting not shewn well inthe others, and also shewing the Castle, the Observatory, and the3-feet telescope. The night promised exceedingly well: but when we gotactually to the telescope it began to cloud and at length becamehopeless. However I saw that the fault which I had remarked on the twopreceding nights was gone. There is now a slight exhibition of anotherfault to a much smaller extent. We shall probably be looking at thetelescope to-day in reference to it. THE CASTLE, PARSONSTOWN, _1848, Sept. 1_. Yesterday we made some alterations in the mounting of the greatmirror. We found that sundry levers were loose which ought to be firm, and we conjectured with great probability the cause of this, forcorrection of which a change in other parts was necessary. The mirrorwas then found to preserve its position much more fixedly thanbefore. . . . At night, upon trying the telescope, we found it veryfaulty for stars near the zenith, where it had been free from faultbefore. The screws which we had driven hard were then loosened, andimmediately it was made very good. Then we tried with some lowerobjects, and it was good, almost equally good, there. For Saturn itwas very greatly superior to what it had been before. Still it is notsatisfactory to us, and at this time a strong chain is in preparation, to support the mirror edgeways instead of the posts that there were atfirst or the iron hoop which we had on it yesterday. Nobody would have conceived that an edgewise gripe of such a mass ofmetal could derange its form in this way. Last night was the finest night we have had as regards clouds, thoughperhaps not the best for definition of objects. THE CASTLE, PARSONSTOWN, _1848, Sept. 2_. I cannot learn that the fault in the mirror had been noticed before, but I fancy that the observations had been very much confined to theZenith and its neighbourhood. 1849 "In July the new constant-service water-pipes to the Observatory werelaid from Blackheath. Before this time the supply of water to theObservatory had been made by a pipe leading up from the lower part ofthe Park, and was not constant. --In May the new staircase from mydwelling-house to the Octagon Room was commenced. --In the Report tothe Visitors there is a curious account of Mr Breen's (one of theAssistants) personal equation, which was found to be different inquantity for observations of the Moon and observations of theStars. --The most important set of observations (of planets) was aseries of measures of Saturn in four directions, at the time when hisring had disappeared. They appear completely to negative the idea thatSaturn's form differs sensibly from an ellipsoid. --Among the GeneralRemarks of the Report the following appears: 'Another change (inprospect) will depend on the use of galvanism; and as a probableinstance of the application of this agent, I may mention that, although no positive step has hitherto been taken, I fully expect inno long time to make the going of all the clocks in the Observatorydepend on one original regulator. The same means will probably beemployed to increase the general utility of the Observatory, by theextensive dissemination throughout the kingdom of accuratetime-signals, moved by an original clock at the Royal Observatory; andI have already entered into correspondence with the authorities of theSouth Eastern Railway (whose line of galvanic communication willshortly pass within nine furlongs of the Observatory) in reference tothis subject. '--I agreed with Schumacher in giving no medal to MrG. P. Bond; his comet was found to be Petersen's. Five medals wereawarded for comets in 1847 (Hind, Colla, Mauvais, Brorsen, Schweizer). --The Liverpool Observatory was finished this year: and thethanks of the Town Council were presented to me. --Respecting Fallows'sObservations at the Cape of Good Hope: I had received the Admiraltysanction for proceeding with calculations in 1846, and I employedcomputers as was convenient. On July 20th of this year I was readywith final results, and began to make enquiries about Fallows'spersonal history, and the early history of the Cape Observatory. OnOct. 23rd I applied for sanction for printing, which was given, andthe work was soon finished off, in the Astronomical Society'sMemoirs. --In the month of March I had commenced correspondence withvarious persons on the imperfect state of publication of the BritishSurvey. Sheets of the Map were issued by scores, but not one of themhad an indication of latitude or longitude engraved. I knew that greatpains had been taken in giving to the principal triangulation a degreeof accuracy never before reached, and in fixing the astronomicallatitudes of many stations with unequalled precision. Finally Iprepared for the Council of the Royal Society a very strongrepresentation on these subjects, which was adopted and presented tothe Government. It was entirely successful, and the Maps were infuture furnished with latitude and longitude lines. --I was electedPresident of the Royal Astronomical Society on Feb. 9th. --In June Iwent with Sheepshanks to see some of the operation of measuring a Baseon Salisbury Plain. The following extract from a letter to his wifedated 1849, June 27th, relates to this expedition: 'In the morning westarted before eight in an open carriage to the Plain: looking intoOld Sarum on our way. The Base is measured on what I should think amost unfavourable line, its north end (from which they have begun now, in verification of the old measure) being the very highest point inthe whole plain, called Beacon Hill. The soldiers measure only 252feet in a day, so it will take them a good while to measure the wholeseven miles. While we were there Col. Hall (Colby's successor) andYolland and Cosset came. '" Of private history: "I made short visits to Playford in January, Apriland July. From July 28th to Sept. 12th I made an expedition with mywife to Orkney and Shetland. --From Dec. 24th to 26th I was atHawkhurst, on a visit to Sir John Herschel. " 1850 "The Report to the Board of Visitors opens with the followingparagraph: 'In recording the proceedings at the Royal Observatoryduring the last year, I have less of novelty to communicate to theVisitors than in the Reports of several years past. Still I trust thatthe present Report will not be uninteresting; as exhibiting, I hope, asteady and vigorous adherence to a general plan long since matured, accompanied with a reasonable watchfulness for the introduction of newinstruments and new methods when they may seem desirable. '--Since theintroduction of the self-registering instruments a good manyexperiments had been made to obtain the most suitable light, and theReport states that 'No change whatever has been made in theseinstruments, except by the introduction of the light of coal-gascharged with the vapour of coal-naptha, for photographicself-registration both of the magnetic and of the meteorologicalinstruments. . . . The chemical treatment of the paper is now so wellunderstood by the Assistants that a failure is almost unknown. And, generally speaking, the photographs are most beautiful, and giveconceptions of the continual disturbances in terrestrial magnetismwhich it would be impossible to acquire from eye-observation. '--Amongst the General Remarks of the Report it is statedthat 'There are two points which have distinctly engaged myattention. The first of these is, the introduction of the Americanmethod of observing transits, by completing a galvanic circuit bymeans of a touch of the finger at the instant of appulse of thetransiting body to the wire of the instrument, which circuit will thenanimate a magnet that will make an impression upon a movingpaper. After careful consideration of this method, I am inclined tobelieve that, in Prof. Mitchell's form, it does possess the advantageswhich have been ascribed to it, and that it may possess peculiaradvantages in this Observatory, where the time-connection of transitsmade with two different instruments (the Transit and the Altazimuth)is of the highest importance. . . . The second point is, the connectionof the Observatory with the galvanic telegraph of the South EasternRailway, and with other lines of galvanic wire with which thattelegraph communicates. I had formerly in mind only the connection ofthis Observatory with different parts of the great British island: butI now think it possible that our communications may be extended farbeyond its shores. The promoters of the submarine telegraph are veryconfident of the practicability of completing a galvanic connectionbetween England and France: and I now begin to think it more thanpossible that, within a few years, observations at Paris and Brusselsmay be registered on the recording surfaces at Greenwich, and viceversa. '--Prof. Hansen was engaged in forming Lunar Tables from hisLunar Theory, but was stopped for want of money. On Mar. 7th Irepresented this privately to Mr Baring, First Lord of the Admiralty;and on Mar. 30th I wrote officially to the Admiralty, soliciting_£150_ with the prospect, if necessary, of making it _£200_. OnApr. 10th the Admiralty gave their assent. The existence of Hansen'sLunar Tables is due to this grant. --The King of Denmark's Medal forComets was discontinued, owing to the difficulties produced by thehostility of Prussia. --On Aug. 1st I gave to the Treasury my opinionon the first proposal for a large reflector in Australia: it was notstrongly favourable. --In August, being (with my wife and Otto Struve)on a visit to Lady Breadalbane at Taymouth Castle, I examined themountain Schehallien. --As in other years, I reported on several Papersfor the Royal Society, and took part in various business for them. --Inthe Royal Astronomical Society I had much official business, asPresident. --In March I communicated to the Athenaeum my views on theExodus of the Israelites: this brought me into correspondence withMiss Corbaux, Robert Stephenson, Capt. Vetch, and Prof. J. D. Forbes. --In December I went to the London Custom House, tosee Sir T. Freemantle (Chairman of Customs), and to see how fardecimal subdivisions were used in the Custom House. " Of private history: "From Mar. 19th to 22nd I was on an expedition toFolkestone, Dover, Dungeness, &c. --From Apr. 3rd to 8th at Playford, and again for short periods in June and July. --From Aug. 1st toSept. 5th I was travelling in Scotland with my wife and Otto Struve(for part of the time). At Edinburgh I attended the Meeting of theBritish Association, and spoke a little in Section A. I was nominatedPresident for 1851 at Ipswich. We travelled to Cape Wrath and returnedby Inverness and the Caledonian Canal. --I was at Playford for a shorttime in October and December. " 1851 "In this year the great shed was built (first erected on the MagneticGround, and about the year 1868 transferred to the South Ground). --Thechronometers were taken from the old Chronometer Room (a room on theupper story fronting the south, now, 1872, called Library 2) and wereput in the room above the Computing Room (where they remained for 10or 12 years, I think): it had a chronometer-oven with gas-heat, erected in 1850. --The following passage is quoted from the Report tothe Visitors:--'As regards Meridional Astronomy our equipment may nowbe considered complete. As I have stated above, an improvement mightyet be made in our Transit Circle; nevertheless I do not hesitate toexpress my belief that no other existing meridional instrument can becompared with it. This presumed excellence has not been obtainedwithout much thought on my part and much anxiety on the part of theconstructors of the instrument (Messrs Ransomes and May, and MrSimms). But it would be very unjust to omit the further statement thatthe expense of the construction has considerably exceeded the originalestimate, and that this excess has been most liberally defrayed by theGovernment. '--In December Sir John Herschel gave his opinion (to theAdmiralty, I believe) in favour of procuring for the Cape Observatorya Transit Circle similar to that at Greenwich. --I had muchcorrespondence about sending Pierce Morton (formerly a pupil of mineat Cambridge, a clever gentlemanly man, and a high wrangler, butsomewhat flighty) as Magnetic Assistant to the Cape Observatory: hewas with me from May to October, and arrived at the Cape onNov. 27th. --I was much engaged with the clock with conical motion ofpendulum, for uniform movement of the Chronographic Barrel. --Regardinggalvanic communications: On Sept. 19th I had prepared a Draft ofAgreement with the South Eastern Railway Company, to which theyagreed. In November I wrote to Sir T. Baring (First Lord of theAdmiralty) and to the Admiralty for sanction, which was given onDec. 18th. In December I had various communications about laying wiresthrough the Park, &c. , &c. , and correspondence about the possibilityof using sympathetic clocks: in June, apparently, I had seenShepherd's sympathetic clock at the Great Exhibition, and had seen thesystem of sympathetic clocks at Pawson's, St Paul's Churchyard. --Inthe last quarter of this year I was engaged in a series ofcalculations of chronological eclipses. On Sept. 30th Mr Bosanquetwrote to me about the Eclipse of Thales, and I urged on thecomputations related to it, through Mr Breen. In October the eclipseof Agathocles (the critical eclipse for the motion of the Moon's node)was going on. In October Hansteen referred me to the darkness atStiklastad. --I went to Sweden to observe the total eclipse of July28th, having received assistance from the Admiralty for the journeysof myself, Mr Dunkin, Mr Humphreys and his friend, and Capt. Blackwood. I had prepared a map of its track, in which animportant error of the _Berliner Jahrbuch_ (arising from neglect ofthe earth's oblateness) was corrected. I gave a lecture at the RoyalInstitution, in preparation for the eclipse, and drew up suggestionsfor observations, and I prepared a scheme of observations forGreenwich, but the weather was bad. The official account of theObservations of the Eclipse, with diagrams and conclusions, is givenin full in a paper published in the Royal Astr. Society'sMemoirs. --This year I was President of the British Association, at theIpswich Meeting: it necessarily produced a great deal of business. Ilectured one evening on the coming eclipse. Prince Albert was present, as guest of Sir William Middleton: I was engaged to meet him atdinner, but when I found that the dinner day was one of the principalsoirée days, I broke off the engagement. --On May 26th I had the firstletter from E. Hamilton (whom I had known at Cambridge) regarding theselection of professors for the University of Sydney. Herschel, Maldon, and H. Denison were named as my coadjutors. Plenty of workwas done, but it was not finished till 1852. --In connection with theclock for Westminster Palace, in February there were considerationsabout providing other clocks for the various buildings; and thisprobably was one reason for my examining Shepherd's Clocks at theGreat Exhibition and at Pawson's. In November I first proposed thatMr E. B. Denison should be associated with me. About the end of theyear, the plan of the tower was supplied to me, with reference to thesuspension of the weights and other particulars. --In 1850 AdmiralDundas (M. P. For Greenwich and one of the Board of Admiralty) hadrequested me to aid the Trustees of the Dee Navigation against anattack; and on Mar. 19th 1851 I went to Chester to see the state ofthe river. On Jan. 1st 1852 I went to give evidence at the OfficialEnquiry. --At a discussion on the construction of the Great Exhibitionbuilding in the Institution of Civil Engineers, I expressed myselfstrongly on the faulty principles of its construction. --In this year Iwrote my first Paper on the landing of Julius Caesar in Britain, andwas engaged in investigations of the geography, tides, sands, &c. , relating to the subject. " Of private history: "I was several times at Playford during January, and went there again on Dec. 23rd. --In this year a very heavymisfortune fell on us. My daughter, Elizabeth, had been on a visit toLady Herschel at Hawkhurst, and on Apr. 2nd Sir J. Herschel wrote tome, saying that she was so well in health. She returned a few dayslater, and from her appearance I was sure that she was suffering underdeadly disease. After some time, an able physician was consulted, whoat once pronounced it to be pulmonary. A sea voyage was thoughtdesirable, and my wife took her to Shetland, where there was again akind welcome from Mr Edmonston. But this, and the care taken on herreturn, availed nothing: and it was determined to take her toMadeira. My wife and daughter sailed in the brig 'Eclipse' fromSouthampton on Dec. 11th. The termination came in 1852. --On Nov. 23rdI went to Bradfield, near Bury: my uncle, George Biddell, died, and Iattended the funeral on Nov. 29th. --From July 18th to Aug. 24th I wasin Sweden for the Observation of the Eclipse, and returned throughHolland. --In October I was about a week at Ventnor and Torquay, andfrom Dec. 7th to 11th at Southampton, on matters connected with mydaughter's illness. " The following extracts are from letters to his wife, relating to theObservation of the eclipse, his interview with the King of Sweden, &c. , and his visit to the pumping engines at Haarlem: _July 28, half-past 10, morning_. The weather is at present most perfectly doubtful. Nearly the wholesky is closely covered, yet there is now and then a momentary gleam ofsun. The chances are greatly against much of the eclipse beingseen. All is arranged to carry off the telescope, &c. , at 11: they canbe carted to the foot of the hill, and we have made out a walking-passthen to the top. We are to dine with Mr Dickson afterwards. _July 28, 10 at night_. Well we have had a glorious day. As soon as we started, the weatherbegan to look better. We went up the hill and planted my telescope, and the sky shewed a large proportion of blue. At first I placed thetelescope on the highest rock, but the wind blew almost a gale, andshook it slightly: so I descended about 8 feet to one side. (The powerof doing this was one of the elements in my choice of this station, which made me prefer it to the high hill beyond the river. ) The viewof scenery was inexpressibly beautiful. The beginning of eclipse waswell seen. The sky gradually thickened from that time, so that the sunwas in whitish cloud at the totality, and barely visible in densecloud at the end of the eclipse. The progress of the eclipse broughton the wonderful changes that you know: just before the totality I sawa large piece of blue sky become pitch black; the horror of totalitywas very great; and then flashed into existence (I do not know how) abroad irregular corona with red flames _instantly seen_ of the mostfantastic kind. The darkness was such that my assistant had very greattrouble in reading his box chronometer. (A free-hand explanatorydiagram is here given. ) Some important points are made out fromthis. 1st the red flames certainly belong to the sun. 2nd theycertainly are in some instances detached. 3rd they are sometimes quitecrooked. 4th they seem to be connected with spots. The corona wasbrilliant white. One star brilliant: I believe Venus. I had no time tomake observations of polarization, &c. , although prepared. When thetotality was more than half over I looked to N. And N. W. , and in theseregions there was the fullest rosy day-break light. After thesun-light reappeared, the black shadow went travelling away to theS. E. Exactly like the thunder-storm from the Main. The day then grewworse, and we came home here (after dinner) in pouring rain. STOCKHOLM, _1851, Aug. 5_. I then by appointment with Sir Edmund Lyons went with him to theMinister for Foreign Affairs, Baron Stjerneld, who received me mostcivilly. My business was to thank him for the orders which had beengiven to facilitate the landing of our telescopes, &c. , &c. He wasquite familiar with the names of my party, Humphreys Milaud, &c. , sothat I trust they have been well received (I have had no letter). Heintimated, I suppose at Sir E. Lyons's suggestion, that perhaps KingOscar might wish to see me, but that it would not be on Tuesday. So Ireplied that I was infinitely flattered and he said that he would senda message to Sir E. Lyons by Tuesday evening. Now all this put me in aquandary: because I wanted to see Upsala, 47 miles off: and thesteamboats on the Mälar only go in the morning and return in themorning: and this was irreconcileable with waiting for his Majesty'sappointment which might be for Wednesday morning. So afterconsultation Sir E. Lyons put me in the hands of a sort of courierattached to the Embassy, and he procured a calèche, and I posted toUpsala yesterday afternoon (knocking the people up at 11 at night) andposted back this afternoon. And sure enough a message has come thatthe king expects me at 11 to-morrow morning. Posting of course is muchdearer than steam-boat travelling, but it is cheap in comparison withEngland: two horses cost 1s. For nearly 7 miles. At Upsala there is avery good old cathedral, I suppose the only one in Sweden: and manythings about the University which interested me. I sent my card toProfessor Fries, and he entirely devoted himself to me: but imagineour conversation--he spoke in _Latin_ and I in French: however weunderstood each other very well. It is on the whole a dreary countryexcept where enlivened by lakes: some parts are pine forests and birchforests, but others are featureless ground with boulder stones, likethe worst part of the Highlands. _August 6, Wednesday, 3 o'clock_. I rigged myself in black trowsers and white waistcoat and neckcloththis morning. Sir Edmund Lyons called. Baron Wrede called on me: hehad observed the Eclipse at Calmar and brought his drawing, much likemine. He conducted me to the Palace. The Minister for Foreign Affairscame to me. In the waiting-room I was introduced to theLieutenant-Governor of Christianstad, who had had the charge ofHumphreys and Milaud. He had placed a _guard of soldiers_ round themwhile they were observing. They saw the eclipse well. CaptainBlackwood went to Helsingborg instead of Bornholm, and saw well. I amsorry to hear that it was cloudy at Christiania, Mr Dunkin'sstation. I heard some days ago that Hind had lost his telescope, but Inow heard a very different story: that he landed at Ystad, and found avery bad hotel there: that he learnt from Murray that the hotels atCarlscrona (or wherever he meant to go) were much worse; and so hegrew faint at heart and turned back. I was summoned in to the Kingand presented by the Minister (Stjerneld), and had a long conversationwith him: on the eclipse, the arc of meridian, the languages, and theUniversities. We spoke in French. Then Baron Wrede went with me to theRittershus (House of Lords or Nobles) in Session, and to the Galleryof Scandinavian Antiquities, which is very remarkable: the collectionof stone axes and chisels, bronze do. , iron do. , ornaments, &c. Isquite amazing. I was struck with seeing specimens from a very distantage of the Maid of Norway's brooch: the use of which I explained tothe Director. I dined and drove out with Sir E. Lyons, and called at the houses ofthe Baron Stjerneld and of the Norwegian Minister Baron Duë, and hadtea at the latter. Most of these people speak English well, and theyseem to live in a very domestic family style. I should soon be quiteat home here: for I perceive that my reception at Court, &c. , makepeople think that I am a very proper sort of person. * * * * * The extract concerning his visit to the Pumping-Engines at Haarlem isas follows: LEYDEN, _1851, August 20, Wednesday_. I went to see the great North Holland Canal, and went a mile or two ina horse-drawn-boat upon it: a very comfortable conveyance. Sawwindmills used for sawing timber and other purposes, as well as somefor grinding and many for draining. Yesterday at half-past one I wentby railway to Haarlem. I did not look at anything in the town exceptgoing through it and seeing that it is a curious fantastic place, butI drove at once to the burgomaster to ask permission to visit one ofthe three great pumping engines for draining the immense Haarlem lake, and then drove to it. Imagine a round tower with a steam-cylinder inits center; and the piston which works up-and-down, instead of workingone great beam as they usually do, works _eight_, poking out ondifferent sides of the round tower, and each driving a pump 6 feet indiameter. I am glad to have seen it. Then by railway here. * * * * * 1852 "Galvanic communication was now established with Lewisham station(thus giving power of communicating with London, Deal, &c. ). --From theReport to the Board of Visitors it appears that, in the case of theTransit Circle, the azimuth of the Instrument as determined byopposite passages of the Pole Star had varied four seconds; and in thecase of the Altazimuth, there was a discordance in the azimuthal zerosof the Instrument, as determined from observations of stars. In bothcases it was concluded that the discordances arose from smallmovements of the ground. --Under the head of 'General Remarks' in theReport, the following paragraph occurs: 'It will be perceived that thenumber of equatoreal observations made here at present is small: andthat they are rarely directed to new comets and similar objects whichsometimes excite considerable interest. This omission isintentional. It is not because the instrumental means are wanting (forour Equatoreals, though not comparable to those of either Cambridge, or of Pulkowa, are fully equal to those usually directed to suchobjects), but it is because these observations are most abundantlysupplied from other observatories, public and private, and because thegain to those observations from our taking a part in them would, probably, be far less than the loss to the important class ofobservations which we can otherwise follow so well. Moreover, I amunwilling to take any step which could be interpreted as attempting todeprive the local and private observatories of honours which they haveso nobly earned. And, finally, in this act of abstinence, I amdesirous of giving an example of adhesion to one principle which, I amconfident, might be extensively followed with great advantage toastronomy:--the principle of division of labour. '--Discoveries ofsmall planets were now not infrequent: but the only one of interest tome is Melpomene, for the following reason. On 1852 June 24 I lost mymost dear, amiable, clever daughter Elizabeth: she died atSouthampton, two days after landing from Madeira. On that evening MrHind discovered the planet; and he requested me to give a name. Iremembered Horace's 'Praecipe lugubres cantus, Melpomene, ' andCowley's 'I called the buskin'd muse Melpomene and told her what sadstory I would write, ' and suggested Melpomene, or Penthos: Melpomenewas adopted. --The first move about the Deal Time Ball was in a letterfrom Commander Baldock to the Admiralty, suggesting that a Time Ball, dropped by galvanic current from Greenwich, should be attached to oneof the South Foreland Lighthouses. The Admiralty sent this for myReport. I went to the place, and I suggested in reply (Nov. 15th) thata better place would be at an old signal station on the chalkdowns. The decisive change from this was made in 1853. --As the resultof my examination and enquiries into the subject of sympatheticclocks, I established 8 sympathetic clocks in the Royal Observatory, one of which outside the entrance gate had a large dial withShepherd's name as Patentee. Exception was taken to this by thesolicitor of a Mr Bain who had busied himself about galvanicclocks. After much correspondence I agreed to remove Shepherd's nametill Bain had legally established his claim. This however was neverdone: and in 1853 Shepherd's name was restored. --In Nov. 1851, Denison had consented to join me in the preparation of the WestminsterClock. In Feb. 1852 we began to have little disagreements. However onApr. 6th I was going to Madeira, and requested him to act with fullpowers from me. --I communicated to the Royal Society my Paper on theEclipses of Agathocles, Thales, and Xerxes. --In the BritishAssociation, I had presided at the Ipswich Meeting in 1851, andaccording to custom I ought to attend at the 1852 Meeting (held atBelfast) to resign my office. But I was broken in spirit by the deathof my daughter, and the thing generally was beyond my willingenterprise. I requested Sir Roderick Murchison to act generally forme: which he did, as I understood, very gracefully. --In this year aproposal was made by the Government for shifting all the Meeting Roomsof the Scientific Societies to Kensington Gore, which was stoutlyresisted by all, and was finally abandoned. " Of private history: "I was at Playford in January, and went thence toChester on the enquiry about the tides of the Dee; and made excursionsto Halton Castle and to Holyhead. --From Apr. 8th to May 14th I was onthe voyage to and from Madeira, and on a short visit to my wife anddaughter there. --On June 23rd I went to Southampton to meet my wifeand daughter just landed from Madeira: on June 24th my dear daughterElizabeth died: she was buried at Playford on June 29th. --I was atPlayford also in July and December. --From Sept. 16th to 24th I went toCumberland, viâ Fleetwood and Peel. " 1853 "On May 3rd 1853 I issued an address to the individual Members of theBoard of Visitors, proposing the extension of the Lunar Reductionsfrom 1830. From this it appears that 'Through the whole period (from1830 to 1853), the places of the Moon, deduced from the observations, are compared with the places computed in the Nautical Almanac: thatis, with Burckhardt's tables, which have been used for many years incomputing the places of the Nautical Almanac. . . . . . . Very lately, however, Mr Adams has shewn that Burckhardt's Parallax is erroneous informula and is numerically incorrect, sometimes to the amount of sevenseconds. In consequence of this, every reduction of the Observationsof the Moon, from 1830 to the present time, is sensibly erroneous. Andthe error is of such a nature that it is not easy, in general, tointroduce its correction by any simple process. . . . The number ofobservations to the end of 1851 (after which time the parallax will becorrected in the current reductions) is about 2560. An expenseapproaching to _£400_ might be incurred in their reduction. 'Subsequently I made application to the Admiralty, and the _£400_ wasgranted on Dec. 12th. --In the Report to the Visitors it is stated thatwith regard to the Transit Circle, changes are under contemplation inits reflection-apparatus: one of these changes relates to the materialof the trough. 'Several years ago, when I was at Hamburgh, my reveredfriend Prof. Schumacher exhibited to me the pacifying effect of acopper dish whose surface had been previously amalgamated withquicksilver. . . . . . . The Rev. Charles Pritchard has lately given muchattention to this curious property of the metals, and has brought thepractical operation of amalgamation to great perfection. Still it isnot without difficulty, on account of a singular crystallization ofthe amalgam. '--With regard to the Chronograph, the Report states: 'TheBarrel Apparatus for the American method of observing transits is notyet brought into use. . . . I have, however, brought it to such a statethat I am beginning to try whether the Barrel moves with sufficientuniformity to be itself used as the Transit Clock. This, if perfectlysecured, would be a very great convenience, but I am not very sanguineon that point. '--A change had been made in the Electrometer-apparatus:'A wire for the collection of atmospheric electricity is now stretchedfrom a chimney on the north-west angle of the leads of the OctagonRoom to the Electrometer pole. . . . There appears to be no doubt that agreater amount of electricity is collected by this apparatus than bythat formerly in use. '--As regards the Magnetical Observations: 'TheVisitors at their last Meeting, expressed a wish that some attemptshould be made to proceed further in the reduction or digest of themagnetical results, if any satisfactory plan could be devised. Icannot say that I have yet satisfied myself on the propriety of anyspecial plan that I have examined. . . . I must, however, confess that, in viewing the capricious forms of the photographic curves, my mind isentirely bewildered, and I sometimes doubt the possibility ofextracting from them anything whatever which can be consideredtrustworthy. '--Great progress had been made with the distribution oftime. 'The same Normal Clock maintains in sympathetic movement thelarge clock at the entrance gate, two other clocks in the Observatory, and a clock at the London Bridge Terminus of the South-EasternRailway. . . . It sends galvanic signals every day along all theprincipal railways diverging from London. It drops the Greenwich Ball, and the Ball on the Offices of the Electric Telegraph Company in theStrand;. . . All these various effects are produced without sensibleerror of time; and I cannot but feel a satisfaction in thinking thatthe Royal Observatory is thus quietly contributing to the punctualityof business through a large portion of this busy country. I have thesatisfaction of stating to the Visitors that the Lords Commissionersof the Admiralty have decided on the erection of a Time-Signal Ball atDeal, for the use of the shipping in the Downs, to be dropped everyday by a galvanic current from the Royal Observatory. The constructionof the apparatus is entrusted to me. Probably there is no roadstead inthe world in which the knowledge of true time is so important. '--TheReport includes an account of the determination of the Longitude ofCambridge Observatory by means of galvanic signals, which appear tohave been perfectly successful. --Under the head of General Remarks thefollowing passage appears: 'The system of combining the labour ofunattached computers with that of attached Assistants tends materiallyto strengthen our powers in everything relating to computation. Wefind also, among the young persons who are engaged merely to serve ascomputers, a most laudable ambition to distinguish themselves asobservers; and thus we are always prepared to undertake anyobservations which may be required, although necessarily by anexpenditure of strength which would usually be employed on some otherwork. '--Considerable work was undertaken in preparing a new set ofmaps of our buildings and grounds. --On Apr. 23rd there was a smallfire in the magnetic observatory, which did little mischief. --InDecember I wrote my description of the Transit Circle. --Lieut. Stratford, the Editor of the Nautical Almanac, died, andthere was some competition for the office. I was willing to takeit at a low rate, for the addition to my salary: Mr Main--and I thinkMr Glaisher--were desirous of exchanging to it: Prof. Adams wasanxious for it. The Admiralty made the excellent choice of MrHind. --In October Faraday and I, at Lothbury, witnessed someremarkable experiments by Mr Latimer Clark on a galvanic currentcarried four times to and from Manchester by subterranean wires (morethan 2000 miles) shewing the retardation of visible currents (at theirmaximum effect) and the concentration of active power. I madeinvestigations of the velocity of the Galvanic Current. --I was engagedon the preliminary enquiries and arrangements for the Deal TimeBall. --With respect to the Westminster Clock; an angry paper wasissued by Mr Vulliamy. In October I expostulated with Denison abouthis conduct towards Sir Charles Barry: on November 7th I resigned. --OnFeb. 11th I was elected President of the Royal AstronomicalSociety. --In the Royal Institution I lectured on the AncientEclipses. --On Dec. 15th I was elected to the Academy ofBrussels. --After preliminary correspondence with Sir W. Molesworth(First Commissioner of Works, &c. ) and Sir Charles Barry (Architect ofthe Westminster Palace), I wrote, on May 14th, to Mr Gladstone aboutdepositing the four Parliamentary Copies of Standards, at the RoyalObservatory, the Royal Mint, the Royal Society, and within a wall ofWestminster Palace. Mr Gladstone assented on June 23rd. --On Mar. 26thI wrote to Mr Gladstone, proposing to take advantage of the new coppercoinage for introducing the decimal system. I was always strenuousabout preserving the Pound Sterling. On May 10th I attended theCommittee of the House of Commons on decimal coinage: and in May andSeptember I wrote letters to the Athenaeum on decimal coinage. --I hadalways something on hand about Tides. A special subject now was, thecry about intercepting the tidal waters of the Tyne by the formationof the Jarrow Docks, in Jarrow Slake; which fear I considered to beridiculous. " Of private history: "From Jan. 15th to 24th I was at Playford. --OnMar. 4th I went to Dover to try time-signals. --From June 24th toAug. 6th I was at Little Braithwaite near Keswick, where I had hired ahouse, and made expeditions with members of my family in alldirections. On July 28th I went, with my son Wilfrid, by Workingtonand Maryport to Rose Castle, the residence of Bishop Percy (the Bishopof Carlisle), and on to Carlisle and Newcastle, looking at variousworks, mines, &c. --On Dec. 24th I went to Playford. " 1854 The chronograph Barrel-Apparatus for the American method of transitshad been practically brought into use: "I have only to add that thisapparatus is now generally efficient. It is troublesome in use;consuming much time in the galvanic preparations, the preparation ofthe paper, and the translation of the puncture-indications intofigures. But among the observers who use it there is but one opinionon its astronomical merits--that, in freedom from personal equationand in general accuracy, it is very far superior to the observationsby eye and ear. "--The printing and publication of the Observations, which was always regarded by Airy as a matter of the first importance, had fallen into arrear: "I stated in my last Report that the printingof the Observations for 1852 was scarcely commenced at the time of thelast meeting of the Visitors. For a long time the printing went on soslowly that I almost despaired of ever again seeing the Observationsin a creditable state. After a most harassing correspondence, theprinters were at length persuaded to move more actively, . . . But thevolume is still very much behind its usual time of publication. "--"TheDeal Time-Ball has now been erected by Messrs Maudslays and Field, andis an admirable specimen of the workmanship of those celebratedengineers. The galvanic connection with the Royal Observatory (throughthe telegraph wires of the South Eastern Railway) is perfect. Theautomatic changes of wire-communications are so arranged that, whenthe Ball at Deal has dropped to its lowest point, it sends a messageto Greenwich to acquaint me, not with the time of the beginning of itsfall (which cannot be in error) but with the fact that it has reallyfallen. The Ball has several times been dropped experimentally withperfect success; and some small official and subsidiary arrangementsalone are wanting for bringing it into constant use. "--The operationsfor the galvanic determination of the longitude of Brussels aredescribed, with the following conclusion: "Thus, about 3000 effectivesignals were made, but only 1000 of these were admissible for thefundamental objects of the operation. The result, I need scarcelyremark, claims a degree of accuracy to which no precedingdetermination of longitude could ever pretend. I apprehend that theprobable error in the difference of time corresponds to not more thanone or two yards upon the Earth's surface. --A careful scheme had beenarranged for the determination of the longitude of Lerwick, but'unfortunately, the demand for chronometers caused by our large navalarmament has been so considerable that I cannot reckon on having at mydisposal a sufficient number to carry on this operation successfully;and I have, therefore, unwillingly deferred it to a more peacefultime. '--The covering stone of Halley's Tomb in Lee Churchyard was muchshattered, and I applied to the Admiralty for funds for its completerestoration: these were granted on Feb. 3rd. --In this year, under mycognizance, _£100_ was added to the Hansen grant. --I had muchcorrespondence and work in connection with the printing of Maclear'swork at the Cape of Good Hope. In June, all accounts, &c. About theTransit Circle were closed at the Admiralty, and the instrument wascompletely mounted at the Cape. --Dr Scoresby (who in his own way wasvery imperious) had attacked my methods of correcting the compass iniron ships: I replied in a letter to the Athenaeum on Oct. 17th. --Imade enquiries about operations for determining the longitude ofVienna, but was utterly repelled by the foreign telegraph offices. --Inthe Royal Astronomical Society; I prepared the Address on presentingthe Medal to Rümker. --In Melbourne University: The first letterreceived was from the Chancellor of the University dated Jan. 26th, requesting that Sir John Herschel, Prof. Malden, Mr Lowe(subsequently Chancellor of the Exchequer), and I would selectprofessors. We had a great deal of correspondence, meetings, examination of testimonials, &c. , and on August 14th we agreed onWilson, Rowe, McCoy, and Hearn. --On Feb. 17th I received the PrussianOrder of Merit. --I had correspondence with the Treasury on the scaleto be adopted for the Maps of the British Survey. I proposed 1/3000, and for some purposes 1/600. --I printed a Paper on the Deluge, inwhich I shewed (I believe to certainty) that the Deluge of Genesis wasmerely a Destructive Flood of the Nile. --Being well acquainted withthe mountains of Cumberland, I had remarked that a 'man' or cairn ofstones erected by the Ordnance Surveyors on the Great Gable hadcovered up a curious natural stone trough, known as one of theremarkable singularities of the country. This year, without giving anynotice to the Ordnance Surveyors, I sent two wallers from Borrowdaleto the mountain top, to remove the 'man' about 10 feet and expose thetrough. Sir Henry James afterwards approved of my act, and refundedthe expense. --I investigated the optical condition of an eye withconical cornea. "The Harton Colliery Experiment: I had long wished to repeat theexperiment which I had attempted unsuccessfully in 1826 and 1828, ofdetermining by pendulum-vibrations the measure of gravity at thebottom of a mine. Residing near Keswick this summer, and having thematter in my mind, I availed myself of an introduction from Dr Leitchto some gentlemen at South Shields, for inspection of the HartonColliery. I judged that it would answer pretty well. I find that onAug. 11th I wrote to Mr Anderson (lessee of the mine), and on the sameday to the Admiralty requesting authority to employ a GreenwichAssistant, and requesting _£100_ for part payment of expenses. OnAugust 16th the Admiralty assent. There were many preparations to bemade, both personal and instrumental. My party consisted of Dunkin(Superintendant), Ellis, Criswick, Simmons, Pogson, and Rümker: I didnot myself attend the detail of observations. The observations beganon Oct. 2nd and ended on Oct. 21st: supplementary observations weresubsequently made at Greenwich for examining the coefficient oftemperature-correction. On Oct. 24th I gave a Lecture at South Shieldson the whole operation. In 'Punch' of Nov. 18th there was an excellentsemi-comic account of the experiment, which as I afterwards found waswritten by Mr Percival Leigh. " Of private history: "On Jan. 18th I returned from Playford. FromMar. 10th to 13th I was at Deal, and visited Sir John Herschel atHawkhurst. --From June 28th to Aug. 7th I was staying with my family atThe Grange, in Borrowdale near Keswick: and also made an expedition toPenrith, Carlisle, Newcastle, Jarrow, &c. ; and descended the HartonPit. --In September and also in October I was at South Shields on theHarton Experiments. --From Dec. 14th to 18th I was at Cambridge, and onthe 26th I went to Playford. " The following letter, written in answer to a lady who had asked him toprocure permission from Lord Rosse for her to observe with histelescope, is characteristic: ROYAL OBSERVATORY, GREENWICH. _1854, September 20_. DEAR MADAM, The state of things with regard to Lord Rosse's Telescope is this. Ifa night is fine, it is wanted for his use or for the use ofprofessional astronomers. If it is not fine, it is of no use toanybody. Now considering this, and considering that the appropriationof the telescope on a fine night to any body but a technicalastronomer is a misapplication of an enormous capital of money andintellect which is invested in this unique instrument--it is againstmy conscience to ask Lord Rosse to place it at the service of anyperson except an experienced astronomer. No introduction, I believe, is necessary for seeing it in the day-time. The instrument standsunenclosed in the Castle Demesne, to which strangers are admittedwithout question, I believe. . . . . . . . . . . . . . . Faithfully yours, G. B. AIRY. 1855 "On May 9th it was notified to me (I think through the Hydrographer)that the Admiralty were not unwilling to increase my salary. I madeapplication therefore; and on Jan. 21st 1856 Sir Charles Wood notifiedto me that the Admiralty consented to have it raised from _£800_ to_£1000_. --In the Report to the Board of Visitors it appears that 'Atthe instance of the Board of Trade, acting on this occasion through aCommittee of the Royal Society, a model of the Transit Circle (withthe improvement of perforated cube, &c. Introduced in the CapeTransit Circle) has been prepared for the Great Exhibition atParis. '--Under the head of Reduction of Astronomical Observations itis stated that 'During the whole time of which I have spoken, thegalvanic-contact method has been employed for transits, with theexception of a few days, when the galvanic apparatus was out of order. From the clock errors, I have deduced the personal equations of theobservers in our usual way. . . . The result is that the magnitude of thepersonal equations in the galvanic-touch method is not above half ofthat in the eye and ear method. '--With regard to the Reduction of theMagnetical Observations, 'I have not yet felt sufficiently satisfiedwith any proposed method of discussing the magnetic results to devoteany time to their further treatment. '--'The Time-Signal Ball at Dealwas brought into regular use at the beginning of the present year. Ina short time, however, its action was interrupted, partly byderangement of the apparatus, and partly by the severity of theweather, which froze the sulphuric acid to the state of jelly. I sentan assistant and workman to put it in order, and since that time ithas generally acted very well. --Application has been made to me fromone of the important offices of Government (the Post Office) for thegalvanic regulation of their clocks. --On considering the risks towhich various galvanic communications are liable, and the financialnecessity for occupying wires as little as possible, I perceived thatit was necessary to devise constructions which should satisfy thefollowing conditions. First, that a current sent once a day shouldsuffice for adjusting the clock, even if it had gone ten or moreseconds wrong. Secondly, that an occasional failure of the currentshould not stop the clock. I have arranged constructions which possessthese characters, and the artist (Mr C. Shepherd) is now engaged inpreparing estimates of the expense. I think it likely that this mayprove to be the beginning of a very extensive system of clockregulation. "--With respect to the operations for determining thelongitude of Paris, it is stated that, "The whole number of days ofsignal transmission was eighteen, and the whole number of signalstransmitted was 2530. The number of days considered available forlongitude, in consequence of transits of stars having been observed atboth Observatories, was twelve, and the number of signals was1703. Very great care was taken on both sides, for the adjustments ofthe instruments. The resulting difference of longitude, 9m. 20. 63s. , is probably very accurate. It is less by nearly 1s. Of time than thatdetermined in 1825 by rocket-signals, under the superintendance of SirJohn Herschel and Col. Sabine. The time occupied by the passage of thegalvanic current appears to be 1/12th of a second. "--With regard tothe Pendulum Experiments in the Harton Colliery, after mentioning thatpersonal assistance had been sought and obtained from theObservatories of Cambridge, Oxford, Durham, and Red Hill, the Reportstates that "The experiments appear to have been in every pointsuccessful, shewing beyond doubt that gravity is increased at thedepth of 1260 feet by 1/10000th part. I trust that this combinationmay prove a valuable precedent for future associations of thedifferent Observatories of the kingdom, when objects requiringextensive personal organization shall present themselves. "--OnOct. 18th the Astronomer Royal printed an Address to the IndividualMembers of the Board of Visitors on the subject of a large newEquatoreal for the Observatory. After a brief statement of theexisting equipment of the Observatory in respect of equatorealinstruments, the Address continues thus: "It is known to the Visitorsthat I have uniformly objected to any luxury of extrameridionalapparatus, which would materially divert us from a steady adherence tothe meridional system which both reason and tradition have engraftedon this Observatory. But I feel that our present instruments areinsufficient even for my wishes; and I cannot overlook theconsideration that due provision must be made for future interests, and that we are nearer by twenty years to the time when anotherjudgment must decide on the direction which shall be given to theforce of the Observatory. "--"In August I had some correspondence aboutthe Egyptian wooden astronomical tablets with Mr Gresswell and others:they were fully examined by Mr Ellis. --In this year I was much engagedon schemes for compasses, and in June I sent my Paper on Discussionsof Ships' Magnetism to the Royal Society. --On Dec. 6th the mast of theObservatory time-ball broke, and the Ball fell in the Front Court. --OnAug. 4th my valued friend Mr Sheepshanks died; and on Aug. 14th I wentto London to see the Standard Bars as left by him. Afterwards, onOct. 25th I went to Reading to collect the papers about Standards leftby Mr Sheepshanks. --I made a mechanical construction for Euclid I. 47, with which I was well satisfied. --On Apr. 13th I joined a deputationto the Chancellor of the Exchequer (Sir G. Cornewall Lewis) on DecimalCoinage. " Of private history: "I was at Playford for a large part ofJanuary. --On Mar, 26th I went to Reading, to visit Mr Sheepshanks, andafterwards to Silchester and Hereford. --On June 21st I went with mywife and two eldest sons to Edinburgh and other places in Scotland, but residing principally at Oban, where I hired a house. Amongst otherexpeditions, I and my son Wilfrid went with the 'Pharos' (NorthernLights Steamer) to the Skerry Vohr Lighthouse, &c. I also visitedNewcastle, &c. , and returned to Greenwich on Aug. 2nd. --From Oct. 12thto 17th I was at Cambridge. --On Dec. 24th I went to Playford. " CHAPTER VII. AT GREENWICH OBSERVATORY--1856 TO 1866. 1856 "In the Report to the Visitors there is an interesting account of thedifficulties experienced with the Reflex Zenith Tube in consequence ofthe tremors of the quicksilver transmitted through the ground. Attempts were made to reduce the tremor by supporting thequicksilver trough on a stage founded at a depth of 10 feet below thesurface, but it was not in the smallest degree diminished, and theReport states that 'The experience of this investigation justifies mein believing that no practicable depth of trench prevents thepropagation of tremor when the soil is like that of Greenwich Hill, agravel, in all places very hard, and in some, cemented to theconsistency of rock. '--With respect to the regulation of the PostOffice clocks, 'One of the galvanic clocks in the Post OfficeDepartment, Lombard Street, is already placed in connection with theRoyal Observatory, and is regulated at noon every day . . . Other clocksat the General Post Office are nearly prepared for the sameregulation, and I expect that the complete system will soon be inaction. '--Under the head of General Remarks a careful summary is givenof the work of the Observatory, and the paragraph concludes asfollows: 'Lastly there are employments which connect the scientificObservatory with the practical world; the distribution of accuratetime, the improvement of marine time-keepers, the observations andcommunications which tend to the advantage of Geography andNavigation, and the study, in a practical sense, of the modificationsof Magnetism; a careful attention to these is likely to prove usefulto the world, and conducive to the material prosperity of theObservatory: and these ought not to be banished from our system. '--InSeptember I prepared the first specification for the building to carrythe S. E. Dome. --In September, learning that Hansen's Lunar Tables werefinished in manuscript, I applied to Lord Clarendon and they wereconveyed to me through the Foreign Office: in October I submitted tothe Admiralty the proposal for printing the Tables, and in November Ilearned that the Treasury had assented to the expense. --Lieut. Daynou's eclipses and occultations for longitudes of pointsin South Africa, observed in 1854 and 1855, were calculatedhere in this year. --On Feb. 16th I made my first application to SirC. Wood (First Lord of the Admiralty) for assistance to C. PiazziSmyth to carry out the Teneriffe Experiment: grounding it in part onthe failure of attempts to see the solar prominences. He gaveencouragement, and on Mar. 18th I transmitted Piazzi Smyth's Memorialto the Admiralty: on May 2nd the Admiralty authorized an expense of_£500_. I drew up suggestions. --The Sheepshanks Fund: After the deathof my friend Richard Sheepshanks, his sister Miss Anne Sheepshankswished to bestow some funds in connection with the University ofCambridge, Trinity College, and Astronomy, to which his name should beattached. There must have been some conversation with me, but thefirst letter is one from De Morgan in August. In September I had aconversation with Miss Sheepshanks, and sent her my first draft of ascheme, to which she assented. On Sept. 30th I wrote to Whewell(Master of Trinity) who was much trusted by Miss Sheepshanks: heconsented to take part, and made some suggestions. There was furthercorrespondence, but the business did not get into shape in thisyear. --In connection with the Correction of the Compass in Iron Ships:I discussed the observations made in the voyage of the RoyalCharter. On Feb. 13th I proposed to the Admiralty a system of mountingthe compasses with adjustable magnets, and it was ordered to be triedin the Trident and Transit. --In February I reported to the Admiraltythat the Deal Time-Ball had been successful, and I proposed time-ballsat Portsmouth, Plymouth, and Sheerness. There was much correspondencein various directions about Portsmouth and Devonport, and in March Iwent to Devonport and specially examined Mount Wise and the DevonportColumn. --I had correspondence with Sir Howard Douglas about the seabreaking over the unfinished Dover Pier. I have an idea that thisfollowed evidence given by me to a Harbour Commission, in which Iexpressed as a certainty that the sea will not be made to break by avertical wall. " Of private history: "I returned from Playford on Jan. 18th. --FromJune 16th to August 5th I was, with my son Wilfrid, on an expeditionto South Italy and Sicily: on our return from Sicily, we remained forthree days ill at Marseilles from a touch of malaria. --On Dec. 22nd Iwent to Playford. --In acknowledgment of the pleasure which I hadderived from excursions in the Cumberland Passes, I made a foot-bridgeover a troublesome stream on the Pass of the Sty Head. " 1857 "In the Report to the Visitors, when on the subject of the Altazimuth, the following paragraph occurs: 'I alluded in a preceding section tothe cutting away of a very small portion of one of the rays of thethree-armed pier which carries the Altazimuth. The quality of thebrickwork is the best that I have ever seen, and not a single brickwas disturbed beyond those actually removed. Yet the effect was togive the Altazimuth an inclination of about 23". This inclinationevidently depends on the elasticity of the brickwork. '--With referenceto the new S. E. Equatoreal the Report states that 'The support of thenorth or upper end of the polar axis has been received, and is plantedwithin the walls of the building in a position convenient for raisingit to its ultimate destination. It is one piece of cast-iron, andweighs nearly 5 tons. '--Small changes as previously mentioned had beennoticed with regard to the Zero of Azimuth of the Transit Circle, andthe Report states that 'In regard to the Azimuth of the TransitCircle, and the Azimuth of its Collimator, Mr Main has broughttogether the results of several years, and the following law appearsto hold. There is a well-marked annual periodical change in theposition of the Transit Circle, the southerly movement of the easternpivot having its minimum value in September, and its maximum in March, the extreme range being about 14 seconds; and there is a similarchange, but of smaller amount, in the position of the Collimator. Icannot conjecture any cause for these changes, except in the motion ofthe ground. There is also a well-marked connection between the stateof level of the axis and the temperature. The eastern pivot alwaysrises when the temperature rises, the extreme range being about 6seconds. I cannot offer any explanation of this. '--Under the head ofExtraneous Works the Report states that 'The British Government hadfor some years past contributed by pecuniary grants to the preparationof Prof. Hansen's Lunar Tables. In the last winter they undertook theentire expense of printing a large impression of the Tables. Thereading of the proof-sheets (a very considerable labour) has beeneffected entirely at the Observatory. I may take this opportunity ofstating that the use of these Tables has enabled me, as I think, incontestably to fix the capture of Larissa to the date B. C. 557, May19. This identification promises to prove valuable, not merely for itschronological utility, but also for its accurate determination of anastronomical epoch, the point eclipsed being exactly known, and theshadow having been very small. '--In April I gave a lecture to theRoyal Astronomical Society on the methods available through the next25 years for the determination of the Sun's parallax. --DrLivingstone's observations for African longitudes were computed at theObservatory. --The Admiralty enquire of me about the feasibility ofadopting Piazzi Smyth's construction for steadying telescopes on boardship: I gave a Report, of mixed character, on the wholediscouraging. --I had correspondence with G. P. Bond and others aboutphotographing the Stars and Moon. --On Feb. 17th Piazzi Smyth's books, &c. Relating to the Teneriffe Experiment were sent to me: Irecommended that an abridged Report should be sent to the RoyalSociety. --Respecting the Sheepshanks Fund: there was correspondencewith Miss Sheepshanks and Whewell, but nothing got into shape thisyear: Miss Sheepshanks transferred to me _£10, 000_ lying at Overendand Gurney's. --In November experiments were made for the longitude ofEdinburgh, which failed totally from the bad state of the telegraphwire between Deptford and the Admiralty. --In June the first suggestionwas made to me by Capt. Washington for time-signals on the LizardPoint: which in no long time I changed for the Start Point. --TheAdmiralty call for estimates for a time-ball at Portsmouth: onreceiving them they decline further proceeding. --I was engaged inspeculations and correspondence about the Atlantic SubmarineCable. --In the Royal Astronomical Society, I presented Memoirs andgave lectures on the three great chronological eclipses (Agathocles, Thales, Larissa). "--On Dec. 5th Airy wrote to the Vice-Chancellor ofthe University of Cambridge, objecting to the proposed changesregarding the Smith's Prizes--a subject in which he took muchinterest, and to which he ascribed great importance. --On Apr. 27th Iwas in correspondence with G. Herbert of the Trinity House, aboutfloating beacons. --In July I reported to the Treasury on the SwedishCalculating Engine (I think on the occasion of Mr Farr, of theRegistrar-General's Office, applying for one). --In November I hadcorrespondence about the launch of the Great Eastern, and the maindrainage of London. " Of private history: "On Jan. 14th I returned from Playford. --From June27th to Aug. 5th I was travelling in Scotland with my wife and twoeldest sons, chiefly in the West Highlands. On our return we visitedMrs Smith (my wife's mother) at Brampton. --On Dec. 26th I went toPlayford. " 1858 "In the Minutes of the Visitors it is noted that the new Queen'sWarrant was received. The principal change was the exclusion of theAstronomer Royal and the other Observatory Officers from theBoard. --In the Report to the Visitors it is stated that 'The Papers ofthe Board of Longitude are now finally stitched into books. They willprobably form one of the most curious collections of the results ofscientific enterprise, both normal and abnormal, which exists. '--Itappears that the galvanic communications, external to the Observatory, had been in a bad state, the four wires to London Bridge havingprobably been injured by a thunderstorm in the last autumn, and theReport states that 'The state of the wires has not enabled us to dropthe Ball at Deal. The feeble current which arrives there has been usedfor some months merely as giving a signal, by which an attendant isguided in dropping the Ball by hand. '--Regarding the new Equatorealthe Report states that 'For the new South-East Equatoreal, theobject-glass was furnished by Messrs Merz and Son in the summer oflast year, and I made various trials of it in a temporary tube carriedby the temporary mounting which I had provided, and finally I was wellsatisfied with it. I cannot yet say that I have certainly divided thesmall star of gamma Andromedae; but, for such a test, a combination offavourable circumstances is required. From what I have seen, I have nodoubt of its proving a first-rate object-glass. '--On March 15th was anannular eclipse of the Sun, for the observation of which I sentparties fully equipped to Bedford, Wellingborough, and MarketHarborough. The observations failed totally in consequence of the badweather: I myself went to Harrowden near Wellingborough. --Respectingthe Altazimuth, the Report states that with due caution as to the zeroof azimuth 'the results of observation are extremely good, very nearlyequal to those of the meridional instrument; perhaps I might say thatthree observations with the Altazimuth are equivalent to two with theTransit Circle. '--Respecting Meteorological Observations the Reportstates that 'The observations of the maximum and minimum thermometersin the Thames, interrupted at the date of the last Report, have beenresumed, and are most regularly maintained. Regarding the Thames asthe grand climatic agent on London and its neighbourhood, I shouldmuch regret the suppression of these observations. '--After muchtrouble the longitude of Edinburgh had been determined: 'the retard ofthe current is 0. 04s very nearly, and the difference of longitudes 12m43. 05s, subject to personal equations. '--The Report concludes thus:'With regard to the direction of our labours, I trust that I shallalways be supported by the Visitors in my desire to maintain thefundamental and meridional system of the Observatory absolutelyintact. This, however, does not impede the extension of our system inany way whatever, provided that such means are arranged for carryingout the extension as will render unnecessary the withdrawal ofstrength from what are now the engrossing objects of theObservatory. '--I had much correspondence on Comets, of which Donati'sgreat Comet was one: the tail of this Comet passed over Arcturus onOctober 5th. --Respecting the Sheepshanks Fund: In September I metWhewell at Leeds, and we settled orally the final plan of thescheme. On Oct. 27th I saw Messrs Sharp, Miss Sheepshanks'ssolicitors, and drew up a Draft of the Deed of Gift. There was muchcorrespondence, and on Nov. 20th I wrote to the Vice-Chancellor ofCambridge University. A counter-scheme was proposed by Dr Philpott, Master of St Catharine's College. By arrangement I attended theCouncil of the University on Dec. 3rd, and explained my views, towhich the Council assented. On Dec. 9th the Senate accepted the giftof Miss Sheepshanks. --I had much correspondence throughout this year, with the Treasury, Herschel, Sabine, and the Royal Society, about thecontinuation of the Magnetic Establishments. The Reductions of theMagnetic Observations 1848-1857 were commenced in February of thisyear, under the direction of Mr Lucas, a computer who had been engagedon the Lunar Reductions. --In this year I came to a final agreementwith the South Eastern Railway Company about defining the terms of ourconnection with them for the passage of Time Signals. I was authorizedby the Admiralty to sign the 'protocol' or Memorandum of Agreement, and it was signed by the South Eastern Railway Directors. --OnAug. 28th I made my first proposal to Sir John Packington (First Lordof the Admiralty) for hourly time signals on the Start Point, and inSeptember I went to the Start to examine localities, &c. On Dec. 23rdthe Admiralty declined to sanction it. --I presented to the RoyalSociety a Paper about drawing a great-circle trace on a Mercator'schart. --In October I gave a Lecture on Astronomy in the Assembly Roomat Bury. --On Jan. 25th I was busied with my Mathematical Tracts forrepublication. "--In this year Airy published in the Athenaeum verycareful and critical remarks on the Commissioners' Draft of Statutesfor Trinity College. He was always ready to take action in theinterests of his old College. This Paper procured him the warmestgratitude from the Fellows of the College. Of private history: "On Jan. 23rd I returned from Playford. From July5th to Aug. 6th I was on an expedition in Switzerland with my twoeldest sons. At Paris we visited Le Verrier, and at Geneva we visitedGautier, De La Rive, and Plantamour. We returned by Brussels. --OnDec. 23rd I went to Playford. "--In this year was erected in PlayfordChurchyard a granite obelisk in memory of Thomas Clarkson. It wasbuilt by subscription amongst a few friends of Clarkson's, and thenegociations and arrangements were chiefly carried out by Airy, whozealously exerted himself in the work which was intended to honour thememory of his early friend. It gave him much trouble during the years1856 to 1858. Here is a letter to the Editor of the Athenaeum on some other Trinitymatters: _1858, November 22_. DEAR SIR, In the Athenaeum of November 20, page 650, column 3, paragraph 4, there is an account of the erection of the statue of Barrow in TrinityCollege Antechapel (Cambridge) conceived in a spirit hostile to theUniversity, and written in great ignorance of the facts. On the latterI can give the writer some information. The Marquis of Lansdowne, who was a Trinity man and whose son was ofTrinity, intimated to the authorities of the College that he wasdesirous of placing in the antechapel a statue of _Milton_. This, regard being had to the customs and the college-feelings of Cambridge, was totally impossible. The antechapel of every college is sacredlyreserved for memorials of the men of that college only; and Milton wasof Christ's College. The Marquis of Lansdowne, on hearing thisobjection, left the choice of the person to be commemorated, tocertain persons of the college, one of whom (a literary character ofthe highest eminence and a profound admirer of Milton) has not residedin Cambridge for many years. Several names were carefully considered, and particularly one (not mentioned by your correspondent) of verygreat literary celebrity, but in whose writings there is ingrained somuch of ribaldry and licentiousness that he was at length givenup. Finally the choice rested on Barrow, not as comparable to Milton, but as a person of reputation in his day and as the best who could befound under all the circumstances. Cromwell never was mentioned; he was a member of Sidney College:moreover it would have been very wrong to select the exponent of anextreme political party. But Cromwell has I believe many admirers inCambridge, to which list I attach myself. I had no part in the negociations above mentioned, but I saw theoriginal letters, and I answer for the perfect correctness of what Ihave stated. But as I am not a principal, I decline to appear inpublic. It is much to be desired, both for the Athenaeum and for the public, that such an erroneous statement should not remain uncorrected. And Iwould suggest that a correction by the Editor would be just andgraceful, and would tend to support the Athenaeum in that highposition which it has usually maintained. I am, dear Sir, Yours very faithfully, G. B. AIRY. _Hepworth Dixon, Esq. _ 1859 "The Report to the Visitors states that 'The Lunar Reductions withamended elements (especially parallax) for correction of Observationsfrom 1831 to 1851 are now completed. It is, I think, matter ofcongratulation to the Observatory and to Astronomy, that there are nowexhibited the results of uninterrupted Lunar Observations extendingthrough more than a century, made at the same place, reduced under thesame superintendence and on the same general principles, and comparedthroughout with the same theoretical Tables. '--After reference to thegreat value of the Greenwich Lunar Observations to Prof. Hansen inconstructing his Tables, and to the liberality of the BritishGovernment in their grants to Hansen, the Report continues thus: 'Astrict comparison of Hansen's Tables with the Greenwich Observationsof late years, both meridional and extra-meridional, was commenced. The same observations had, in the daily routine of the Observatory, been compared with the Nautical Almanac or Burckhardt's Tables. Theresult for one year only (1852) has yet reached me, but it is mostremarkable. The sum of squares of residual errors with Hansen's Tablesis only one-eighth part of that with Burckhardt's Tables. When it isremembered that in this is included the entire effect of errors andirregularities of observation, we shall be justified in consideringHansen's Tables as nearly perfect. So great a step, to the best of myknowledge, has never been made in numerical physical theory. I havecited this at length, not only as interesting to the Visitors from thecircumstance that we have on our side contributed to this greatadvance, but also because an innovation, peculiar to this Observatory, has in no small degree aided in giving a decisive character to thecomparison. I have never concealed my opinion that the introductionand vigorous use of the Altazimuth for observations of the Moon is themost important addition to the system of the Observatory that has beenmade for many years. The largest errors of Burckhardt's Tables wereput in evidence almost always by the Altazimuth Observations, inportions of the Moon's Orbit which could not be touched by themeridional instruments; they amounted sometimes to nearly 40" of arc, and they naturally became the crucial errors for distinction betweenBurckhardt's and Hansen's Tables. Those errors are in all casescorrected with great accuracy by Hansen's Tables. '--The Reportconcludes with the following paragraph: 'With the inauguration of thenew Equatoreal will terminate the entire change from the old state ofthe Observatory. There is not now a single person employed orinstrument used in the Observatory which was there in Mr Pond's time, nor a single room in the Observatory which is used as it was usedthen. In every step of change, however, except this last, the ancientand traditional responsibilities of the Observatory have been mostcarefully considered: and, in the last, the substitution of a newinstrument was so absolutely necessary, and the importance oftolerating no instrument except of a high class was so obvious, thatno other course was open to us. I can only trust that, while the useof the Equatoreal within legitimate limits may enlarge the utility andthe reputation of the Observatory, it may never be permitted tointerfere with that which has always been the staple and standard workhere. '--Concerning the Sheepshanks Fund: There was much correspondenceabout settling the Gift till about Feb. 21st. I took part in the firstexamination for the Scholarship in October of this year, and took myplace with the Trinity Seniority, as one of their number on thisfoundation, for some general business of the Fund. --With respect tothe Correction of the Compass in Iron Ships: I sent Mr Ellis toLiverpool to see some practice there in the correction of theCompass. In September I urged Mr Rundell to make a voyage in the GreatEastern (just floated) for examination of her compasses, and lent himinstruments: very valuable results were obtained. Mr Archibald Smithhad edited Scoresby's Voyage in the Royal Charter, with anintroduction very offensive to me: I replied fully in the Athenaeum ofNov. 7th. --The Sale of Gas Act: An Act of Parliament promoted byprivate members of the House of Commons had been passed, without theknowledge or recollection of the Government. It imposed on theGovernment various duties about the preparation of Standards. Suddenly, at the very expiration of the time allowed thiscame to the knowledge of Government. On Oct. 1st Lord Monteagleapplied to me for assistance. On Oct. 15th and 22nd I wrote to MrHamilton, Secretary of the Treasury, and received authority to ask forthe assistance of Prof. W. H. Miller. --I made an examination of MrBall's eyes (long-sighted and short-sighted I think). --In February Imade an Analysis of the Cambridge Tripos Examination, which Icommunicated to some Cambridge residents. " In a letter on this subjectto one of his Cambridge friends Airy gives his opinion as follows: "Ihave looked very carefully over the Examination Papers, and think themon the whole very bad. They are utterly perverted by the insane loveof Problems, and by the foolish importance given to wholly uselessparts of Algebraical Geometry. For the sake of these, every PhysicalSubject and every useful application of pure mathematics are cut downor not mentioned. " This led to much discussion at Cambridge. In thisyear the Smith's Prizes were awarded to the 4th and 6th Wranglers. Of private history: "On Apr. 29th Mrs Smith (my wife's mother) died atBrampton. --From July 4th to Aug. 2nd I was in France (Auvergne and theVivarais) with my two eldest sons. Maclear travelled with us toParis. --On Dec. 23rd I went to Playford. "--Antiquities and historicalquestions connected with military movements had a very greatattraction for Airy. On his return from the expedition in Franceabove-mentioned, he engaged in considerable correspondence withmilitary authorities regarding points connected with the battle ofToulouse. And in this year also he had much correspondence with theDuke of Northumberland concerning his Map of the Roman Wall, and themilitary points relating to the same. 1860 "In June Mr Main accepted the office of Radcliffe Observer at Oxford(Mr Johnson having died) and resigned the First Assistancy atGreenwich: in October Mr Stone was appointed First Assistant. --At anadjourned Meeting of the Visitors on June 18th there were very heavydiscussions on Hansen's merits, and about the grant to him. Paperswere read from Sir J. Lubbock, Babbage, South, Whewell, andme. Finally it was recommended to the Government to grant _£1000_ toHansen, which was paid to him. --In the Report to the Board of Visitorsthe following remark occurs: 'The apparent existence of a discordancebetween the results of Direct Observations and Reflection Observations(after the application of corrections for flexure, founded uponobservations of the horizontal collimator wires) to an extent fargreater than can be explained by any disturbance of the direction ofgravity on the quicksilver by its distance from the vertical, or bythe attraction of neighbouring masses, perplexes me much. '--Withrespect to the discordance of dips of the dipping-needles, which foryears past had been a source of great trouble and puzzle, the Reportstates that 'The dipping-needles are still a source of anxiety. Theform which their anomalies appear to take is that of a special orpeculiar value of the dip given by each separate needle. With one ofthe 9-inch needles, the result always differs about a quarter of adegree from that of the others. I can see nothing in its mechanicalconstruction to explain this. --Reference is made to the spontaneouscurrents through the wires of telegraph companies, which arefrequently violent and always occur at the times of magnetic storms, and the Report continues 'It may be worth considering whether it wouldever be desirable to establish in two directions at right angles toeach other (for instance, along the Brighton Railway and along theNorth Kent Railway) wires which would photographically register in theRoyal Observatory the currents that pass in these directions, exhibiting their indications by photographic curves in closejuxtaposition with the registers of the magnetic elements. '--Inconnection with the Reduction of the Greenwich Lunar Observations from1831 to 1851, the Report states that 'The comparison of Hansen's LunarTables with the Greenwich Observations, which at the last Visitationhad been completed for one year only, has now been finished for thetwelve years 1847 to 1858. The results for the whole period agreeentirely, in their general spirit, with those for the year 1852 citedin the last Report. The greatest difference between the merits ofBurckhardt's and Hansen's Tables appears in the Meridional Longitudes1855, when the proportion of the sum of squares of errors is as 31(Burckhardt) to 2 (Hansen). The nearest approach is in the AltazimuthLatitudes 1854, when the proportion of the sum of squares of errors isas 12 (Burckhardt) to 5 (Hansen). '--A special Address to the Membersof the Board of Visitors has reference to the proposals of M. Struvefor (amongst other matters) the improved determination of thelongitude of Valencia, and the galvanic determination of the extremeEastern Station of the British triangles. --On Sept. 13th I circulatedamongst the Visitors my Remarks on a Paper entitled 'On the PolarDistances of the Greenwich Transit-Circle, by A. Marth, ' printed inthe Astronomische Nachrichten; the Paper by Mr Marth was an elaborateattack on the Greenwich methods of observation, and my Remarks were adetailed refutation of his statements. --On Oct. 20th I made enquiry ofSabine as to the advantage of keeping up magnetic observations. OnOct. 22nd he wrote, avoiding my question in some measure, but sayingthat our instruments must be changed for such as those at Kew (hisobservatory): I replied, generally declining to act on thatadvice. --In March and April I was in correspondence with Mr Cowper(First Commissioner of Works, &c. ) about the bells of the WestminsterClock; also about the smoky chimneys of the various apartments of thePalace. On Apr. 21st I made my Report on the clock and bells, 20foolscap pages. I employed a professional musician to examine thetones of the bells. --In November I was writing my book on ProbableErrors, &c. --I was engaged on the Tides of Kurrachee and Bombay. --Thefirst examination of Navy telescopes was made for the Admiralty. --Hoch's Paper on Aberration appeared in the AstronomischeNachrichten. This (with others) led to the construction of thewater-telescope several years later. --In September I wrote in theAthenaeum against a notion of Sir H. James on the effect of anupheaval of a mountain in changing the Earth's axis. In October I haddrawn up a list of days for a possible evagation of the Earth's poles:but apparently nothing was done upon them. "In this year I was a good deal occupied for the LighthouseCommission. On Feb. 21st Admiral Hamilton (chairman) applied to me forassistance. In April I went to Chance's Factory in Birmingham on thisbusiness. In May I made my report on the Start Lighthouse, afterinspection with the Commission. In June, with my son Hubert, I visitedthe Whitby Lighthouses, and discovered a fault of a singular kindwhich most materially diminished their power. This discovery led to ageneral examination of lighthouses by the Trinity Board, to amodification of many, and to a general improvement of system. On June25th I reported on the Lights at Calais, Cap de Valde, Grisnez, SouthForeland, and North Foreland. In August I had been to the NorthForeland again, and in September to Calais and the Cap d'Ailly. InOctober I went with my son Hubert to Aberdeen to see the GirdlenessLighthouse. On Nov. 10th I made a General Report. "This was the year of the great total solar eclipse visible inSpain. At my representation, the Admiralty placed at my command thelarge steamship 'Himalaya' to carry about 60 astronomers, British andForeign. Some were landed at Santander: I with many at Bilbao. TheEclipse was fairly well observed: I personally did not do my partwell. The most important were Mr De La Rue's photographic operations. At Greenwich I had arranged a very careful series of observations withthe Great Equatoreal, which were fully carried out. " The eclipse expedition to Spain, shortly referred to above, was mostinteresting, not merely from the importance of the results obtained(and some of the parties were very fortunate in the weather) but fromthe character of the expedition. It was a wonderful combination ofthe astronomers of Europe, who were all received on board the'Himalaya, ' and were conveyed together to the coast of Spain. Thepolyglot of languages was most remarkable, but the utmost harmony andenthusiasm prevailed from first to last, and this had much to do withthe general success of the expedition. Those who landed at Bilbaowere received in the kindest and most hospitable manner by MrC. B. Vignoles, the engineer-in-chief of the Bilbao and Tudela Railway, which was then under construction. This gentleman made arrangementsfor the conveyance of parties to points in the interior of the countrywhich were judged suitable for the observation of the eclipse, andplaced all the resources of his staff at the disposal of theexpedition in the most liberal manner. The universal opinion was thatvery great difficulty would have been experienced without the activeand generous assistance of Mr Vignoles. It is needless to say that thevote of thanks to Mr Vignoles, proposed by the Astronomer Royal duringthe return voyage, was passed by acclamation and with a very sincerefeeling of gratitude: it was to the effect that 'without the great andliberal aid of Mr C. B. Vignoles, and the disinterested love of scienceevinced by him on this occasion, the success of the "Himalaya" eclipseexpedition could not have been ensured. ' There is a graphic andinteresting account of the reception of the party at Bilbao given inthe 'Life of C. B. Vignoles, F. R. S. , Soldier and Civil Engineer, ' byO. J. Vignoles, M. A. Of private history: "On May 26th my venerable friend Arthur Biddelldied. He had been in many respects more than a father to me: I cannotexpress how much I owed to him, especially in my youth. --From June12th to 15th I visited the Whitby Lighthouses with my sonHubert. --From July 6th to 28th I was in Spain, on the 'Himalaya'expedition, to observe the total eclipse: I was accompanied by mywife, my eldest son, and my eldest daughter. --From Oct. 5th to 18th Iwent with my son Hubert to Aberdeen to see the Girdleness Lighthouse, making lateral trips to Cumberland in going and returning. --OnDec. 21st I went to Playford. " 1861 "In the Report to the Visitors there is great complaint of want ofroom. 'With increase of computations, we want more room for computers;with our greatly increased business of Chronometers andTime-Distribution, we are in want of a nearly separate series of roomsfor the Time-Department: we want rooms for book-stores; and we requirerooms for the photographic operations and the computations of theMagnetic Department. '--The Report gives a curious history of DrBradley's Observations, which in 1776 had been transferred to theUniversity of Oxford, and proceeds thus: 'More lately, I applied (inthe first instance through Lord Wrottesley) to the Vice-Chancellor, DrJeune, in reference to the possibility of transferring thesemanuscripts to the Royal Observatory. . . . Finally, a decree for thetransfer of the manuscript observations to the Royal Observatory, without any condition, was proposed to Convocation on May 2nd, and waspassed unanimously. And on May 7th my Assistant, Mr Dunkin, was sentto Oxford to receive them. And thus, after a delay of very nearly acentury, the great work of justice is at length completed, and thegreat gap in our manuscript observations is at length filledup. '--With reference to the Transit Circle, it had been remarked thatthe Collimators were slightly disturbed by the proximity of thegas-flames of their illuminators, and after various experiments as tothe cause of it, the Report proceeds thus: 'To my great surprise, Ifound that the disturbance was entirely due to the radiation of theflame upon a very small corner (about 16 square inches) of the largeand massive stone on which the collimator is planted. The tin plateswere subsequently shaped in such a manner as to protect the stone aswell as the metal; and the disturbance has entirely ceased. '--Regarding the large S. E. Equatoreal, the Report states that'On the character of its object-glass I am now able to speak, first, from the examination of Mr Otto Struve, made in a favourable state ofatmosphere; secondly, from the examinations of my Assistants (I havenot myself obtained a sight of a test-object on a night of very gooddefinition). It appears to be of the highest order. The small star ofgamma Andromedae is so far separated as to shew a broad dark spacebetween its components. Some blue colour is shewn about the brightplanets. '--It is noted in the Report that 'The Equatoreal observationsof the Solar Eclipse are completely reduced; and the results arevaluable. It appears from them that the error in right ascension ofBurckhardt's Lunar Tables at the time of the eclipse amounted to about38"; while that of Hansen's (ultimately adopted by Mr Hind for thecalculation of the eclipse) did not exceed 3". '--With regard toChronometers it is stated that 'By use of the Chronometer Oven, towhich I have formerly alluded, we have been able to give greatattention to the compensation. I have reason to think that we areproducing a most beneficial effect on the manufacture and adjustmentof chronometers in general. '--With regard to the Cape of Good HopeObservatory and Survey, the Admiralty enquire of me when the Surveywork will be completed, and I enquire of Maclear 'How is the printingof your Survey Work?' In 1862 I began to press it strongly, and in1863 very strongly. --I introduced a method (constantly pursued sincethat time at the Royal Observatory) for computing interpolationswithout changes of sign. --I had correspondence with Herschel andFaraday, on the possible effect of the Sun's radiant heat on the sea, as explaining the curve of diurnal magnetic inequality. (That diurnalinequality was inferred from the magnetic reductions 1848-1857, whichwere terminated in 1860. )--Regarding the proposal of hourlytime-signals on the Start Point, I consulted telegraph engineers uponthe practical points, and on Dec. 21st I proposed a formal scheme, incomplete detail. (The matter has been repeatedly brought before theAdmiralty, but has been uniformly rejected. )--I was engaged on thequestion of the bad ocular vision of two or three persons. --TheBritish Association Meeting was held at Manchester: I was President ofSection A. I gave a Lecture on the Eclipse of 1860 to an enormousattendance in the Free Trade Hall. " The following record of theLecture is extracted from Dr E. J. Routh's Obituary Notice of Airywritten for the Proceedings of the Royal Society. "At the meeting ofthe British Association at Manchester in 1861, Mr Airy delivered aLecture on the Solar Eclipse of 1860 to an assembly of perhaps 3000persons. The writer remembers the great Free Trade Hall crowded toexcess with an immense audience whose attention and interest, notwithstanding a weak voice, he was able to retain to the very end ofthe lecture. . . . The charm of Professor Airy's lectures lay in theclearness of his explanations. The subjects also of his lectures weregenerally those to which his attention had been turned by othercauses, so that he had much that was new to tell. His manner wasslightly hesitating, and he used frequent repetitions, which perhapswere necessary from the newness of the ideas. As the lecturerproceeded, his hearers forgot these imperfections and found theirwhole attention rivetted to the subject matter. " Of private history: "On Jan. 2nd there was a most remarkablecrystallization of the ice on the flooded meadows at Playford: thefrost was very severe. --From June 20th to Aug. 1st I was at the Grangenear Keswick (where I hired a house) with my wife and most of myfamily. --From Nov. 5th to 14th I was on an expedition in the South ofScotland with my son Wilfrid: we walked with our knapsacks by theRoman Road across the Cheviots to Jedburgh. --On Dec. 21st I went toPlayford. " 1862 "The Report to the Board of Visitors states that 'A new range ofwooden buildings (the Magnetic Offices) is in progress at theS. S. E. Extremity of the Magnetic Ground. It will include sevenrooms. '--Also 'I took this opportunity (the relaying of thewater-main) of establishing two powerful fire-plugs (one in the FrontCourt, and one in the Magnetic Ground); a stock of fire-hose adaptedto the "Brigade-Screw" having been previously secured in theObservatory. '--'Two wires, intended for the examination of spontaneousearth-currents, have been carried from the Magnetic Observatory to theRailway Station in the town of Greenwich. From this point one wire isto be led to a point in the neighbourhood of Croydon, the other to apoint in the neighbourhood of Dartford. Each wire is to be connectedat its two extremities with the Earth. The angle included between thegeneral directions of these two lines is nearly a right angle. '--'TheKew unifilar magnetometer, adapted to the determination of thehorizontal part of terrestrial magnetic force in absolute measure, wasmounted in the summer of 1861; and till 1862 February, occasionalobservations (14 in all) were taken simultaneously with the old andwith the new instrument. The comparison of results shewed a steady butvery small difference, not greater probably than may correspond to theomission of the inverse seventh powers of distance in the theoreticalinvestigation; proving that the old instrument had been quiteefficient for its purpose. '--Great efforts had been made to deduce alaw from the Diurnal Inequalities in Declination and Horizontal Force, as shewn by the Magnetic observations; but without success: the Reportstates that 'The results are most amazing, for the variation inmagnitude as well as in law. What cosmical change can be indicated bythem is entirely beyond my power of conjecture. '--'I have alluded, inthe two last Reports, to the steps necessary, on the English side, forcompleting the great Arc of Parallel from Valencia to the Volga. TheRussian portion of the work is far advanced, and will be finished (itis understood) in the coming summer. It appeared to me therefore thatthe repetition of the measure of astronomical longitude betweenGreenwich and Valencia could be no longer delayed. Two Assistants ofthe Royal Observatory (Mr Dunkin and Mr Criswick) will at once proceedto Valencia, for the determination of local time and the management ofgalvanic signals. '--'I now ask leave to press the subject of HourlyTime Signals at the Start Point on the attention of the Board, and tosubmit the advantage of their addressing the Board of Admiralty uponit. The great majority of outward-bound ships pass within sight of theStart, and, if an hourly signal were exhibited, would have the meansof regulating their chronometers at a most critical part of theirvoyage. The plan of the entire system of operations is completelyarranged. The estimated expense of outfit is _£2017_, and theestimated annual expense is _£326_; both liable to some uncertainty, but sufficiently exact to shew that the outlay is inconsiderable incomparison with the advantages which might be expected from it. I knowno direction of the powers of the Observatory which would tend soenergetically to carry out the great object of its establishment, viz. "the finding out the so much desired Longitude at Sea. "'--Theattention of the Visitors is strongly drawn to the pressure on thestrength of the Observatory caused by the observation of the numeroussmall planets, and the paragraph concludes thus: 'I shall, however, again endeavour to effect a partition of this labour with some otherObservatory. '--A small fire having occurred in the MagneticObservatory, a new building of zinc, for the operation ofnaphthalizing the illuminating gas, is in preparation, external to theObservatory: and thus one of the possible sources of accidental firewill be removed. --Miss Sheepshanks added, through me, _£2000_ to herformer gift: I transferred it, I believe, to the Master and Seniors ofTrinity College. "--In this year Airy contributed to the Royal Societytwo Papers, one "On the Magnetic properties of Hot-Rolled andCold-Rolled Malleable Iron, " the other "On the Strains in the Interiorof Beams. " He gave evidence before the Select Committee on Weights andMeasures, and also before the Public Schools Commission. In the latter part of 1862 a difference arose between Airy andMajor-General Sabine, in consequence of remarks made by the latter ata meeting of the Committee of Recommendations of the BritishAssociation. These remarks were to the effect "That it is necessary tomaintain the complete system of self-registration of magneticphenomena at the Kew Observatory, because no sufficient system ofmagnetic record is maintained elsewhere in England"; implyingpointedly that the system at the Royal Observatory of Greenwich wasinsufficient. This matter was taken up very warmly by Airy, and aftera short and acrimonious correspondence with Sabine, he issued aprivate Address to the Visitors, enclosing copies of thecorrespondence with his remarks, and requesting the Board to take thematter of this attack into their careful consideration. This Addressis dated November 1862, and it was followed by another dated January1863, which contains a careful reply to the various points of GeneralSabine's attack, and concludes with a distinct statement that he (theAstronomer Royal) can no longer act in confidence with Sabine as aMember of the Board of Visitors. Of private history: There were the usual short visits to Playford atthe beginning and end of the year. --From June 28th to Aug. 5th he wasin Scotland (chiefly in the Western Highlands) with his wife and hissons Hubert and Osmund. In the course of this journey he visited theCorryvreckan whirlpool near the island of Scarba, and the followingparagraph relating to this expedition is extracted from his journal:"Landed in Black Mile Bay, island of Luing, at 10. 30. Here by previousarrangement with Mr A. Brown, agent of the steam-boat company, a4-oared boat was waiting to take us to Scarba and the Corryvreckan. Wewere pulled across to the island of Lunga, and rowed along its length, till we came to the first channel opening from the main sea, which thesailors called the Little Gulf. Here the sea was rushing inwards in amanner of which I had no conception. Streams were running with ravingspeed, sometimes in opposite directions side by side, with highbroken-headed billows. Where the streams touched were sometimes greatwhirls (one not many yards from our boat) that looked as if they wouldsuck anything down. Sometimes among all this were great smooth partsof the sea, still in a whirling trouble, which were surrounded by themad currents. We seemed entirely powerless among all these. " In the beginning of this year (1862) the Duke of Manchester, inwriting to the Rev. W. Airy, had said, "I wish your brother, theAstronomer Royal, could be induced to have investigations made as towhether the aspects of the Planets have any effect on the weather. "This enquiry produced the following reply: A subject like that of the occult influences of the planets (using theword occult in no bad sense but simply as meaning not _thoroughly_traced) can be approached in two ways--either by the à prioriprobability of the existence of such influences, or by the àposteriori evidence of their effects. If the two can be combined, thesubject may be considered as claiming the dignity of a science. Evenif the effects alone are certain, it may be considered that we have ascience of inferior degree, wanting however that definiteness of lawand that general plausibility which can only be given when truecauses, in accordance with antecedent experience in other cases, canbe suggested. Now in regard to the à priori probability of the existence ofplanetary influences, I am far from saying that such a thing isimpossible. The discoveries of modern philosophy have all tended toshew that there may be many things about us, unknown even to thescientific world, but which well-followed accidents reveal with themost positive certainty. It is known that every beam of light isaccompanied by a beam of chemical agency, totally undiscoverable tothe senses of light or warmth, but admitting of separation from theluminous and warm rays; and producing photogenic effects. We knowthat there are disturbances of magnetism going on about us, affectingwhole continents at a time, unknown to men in general, but traceablewith facility and certainty, and which doubtless affect even ourbrains and nerves (which are indisputably subject to the influence ofmagnetism). Now in the face of these things I will not undertake to say that thereis any impossibility, or even any want of plausibility in thesupposition that bodies external to the earth may affect us. It maywell be cited in its favour that it is certain that the sun affectsour magnetism (it is doubtful whether it does so _im_mediately, ormediately by giving different degrees of warmth to different parts ofthe earth), and it is believed on inferior evidence that the moon alsoaffects it. It may therefore seem not impossible or unplausible thatother celestial bodies may affect perhaps others of the powers ofnature about us. But there I must stop. The denial of theimpossibility is no assertion of the truth or probability, and Iabsolutely decline to take either side--either that the influences arereal, or that the influences are unreal--till I see evidence of theireffects. Such evidence it is extremely difficult to extract from ordinary factsof observation. I have alluded to the sun's daily disturbance of themagnet as one of the most certain of influences, yet if you were toobserve the magnet for a single day or perhaps for several days, youmight see no evidence of that influence, so completely is it involvedwith other disturbances whose causes and laws are totally unknown. I believe that, in addition to the effects ascribable to Newtoniangravitation (as general motion of the earth, precession of theequinoxes, and tides), this magnetic disturbance is the only one yetestablished as depending on an external body. Men in general, however, do not think so. It appears to be a law of the human mind, to love totrace an effect to a cause, and to be ready to assent to any speciouscause. Thus all practical men of the lower classes, even those whosepecuniary interests are concerned in it, believe firmly in theinfluence of the moon upon the winds and the weather. I believe thatevery careful examiner of recorded facts (among whom I place myself asregards the winds) has come to the conclusion that the influence ofthe moon is not discoverable. I point out these two things (magnetic disturbances and weather) astending to shew that notoriety or the assumed consent of practicalmen, are of no value. The unnotorious matter may be quite certain, thenotorious matter may have no foundation. Everything must stand on itsown evidence, as completely digested and examined. Of such evidence the planetary influence has not a particle. My intended short note has, in the course of writing, grown up into adiscourse of very unreasonable length; and it is possible that a largeportion of it has only increased obscurity. At any rate I can addnothing, I believe, which can help to explain more fully my views onthis matter. * * * * * In this year (1862, June 9th) Airy received the Honorary Degree ofLL. D. In the University of Cambridge. He was nominated by the Duke ofDevonshire, as appears from the following letter: LISMORE CASTLE, IRELAND, _April 19th, 1862_. MY DEAR SIR, It is proposed according to usage to confer a considerable number ofHonorary Degrees on the occasion of my first visit to Cambridge asChancellor of the University. I hope that you will allow me to include your name in that portion ofthe list which I have been invited to draw up. The ceremony is fixed for the 10th of June. I am, my dear Sir, Yours very truly, DEVONSHIRE. _The Astronomer Royal_. * * * * * Airy's reply was as follows: ROYAL OBSERVATORY, GREENWICH, LONDON, S. E. _1862, April 21_. MY LORD DUKE, I am exceedingly gratified by your communication this day received, conveying a proposal which I doubt not is suggested by your Grace'srecollection of transactions now many years past. I have always been desirous of maintaining my connection with myUniversity, and have in various ways interested myself practically inits concerns. It would give me great pleasure to have the connectionstrengthened in the flattering way which you propose. I had conceived that alumni of the University were not admissible tohonorary degrees; but upon this point the information possessed byyour Grace, as Chancellor of the University, cannot be disputed. I am, my Lord Duke, Your Grace's very faithful servant, G. B. AIRY. _His Grace The Duke of Devonshire_. * * * * * There were in all 19 Honorary Degrees of Doctor of Laws conferred onthe 9th of June, including men of such eminence as Armstrong, Faraday, and Fairbairn. 1863 In this year there were several schemes for a Railway through thelower part of Greenwich Park, the most important being the scheme ofthe London, Chatham and Dover Railway Company. In reference to thisscheme the Report to the Visitors states "I may say briefly that Ibelieve that it would be possible to render such a railway innocuousto the Observatory; it would however be under restrictions which mightbe felt annoying to the authorities of the Railway, but whoserelaxation would almost ensure ruin to the Observatory. "--"Themeridional observations of Mars in the Autumn of 1862 have beencompared with those made at the Observatory of Williamstown, nearMelbourne, Australia, and they give for mean solar parallax the value8. 932", exceeding the received value by about 1/24th part. (A valuenearly identical with this 8. 93" has also been found by comparing thePulkowa and Cape of Good Hope Observations. )"--"The results of the newDip-Instrument in 1861 and 1862 appear to give a firm foundation forspeculations on the state and change of the dip. As a general result, I may state as probable that the value of dip in the middle of 1843was about 69°1', and in the middle of 1862 about 68°11'. The decreaseof dip appears to be more rapid in the second half of this intervalthan in the first; the dip at beginning of 1853 being about68°44'. "--With reference to the re-determination of the longitude ofValencia, it is stated that "The concluded longitude agrees almostexactly with that determined by the transmission of chronometers in1844; and entitles us to believe that the longitudes of Kingstown andLiverpool, steps in the chronometer conveyance, were determined withequal accuracy. "--"The computations, for inferring the direction andamount of movement of the Solar System in space from the observedproper motions of 1167 stars, have been completed. The result is, thatthe Sun is moving towards a point, R. A. 264°, N. P. D. 65° (not verydifferent from Sir W. Herschel's, but depending much in N. P. D. On theaccuracy of Bradley's quadrant observations), and that its annualmotion subtends, at the distance of a star of the first magnitude, theangle 0. 4". But the comparison, of the sum of squares of apparentproper motions uncorrected, with the sum of squares of apparent propermotions corrected for motion of Sun, shews so small an advance in theexplanation of the star's apparent movements as to throw great doubton the certainty of results; the sum of squares being diminished byonly 1/25th part. "--"I had been writing strongly to Maclear on thedelays in publishing both the geodetic work and the Star Catalogue atthe Cape of Good Hope: he resolves to go on with these works. InDecember I am still very urgent about the geodesy. " Of private history: There was the usual short visit to Playford at thebeginning and end of the year. --"From June 27th to August 10th I wastravelling in the North and West of Scotland with my wife, my youngestson Osmund, and my daughter Annot. " * * * * * In this year the offer of Knighthood (for the third time) was made toAiry through the Rt Hon. Sir George C. Lewis, Bart. The offer wasaccepted on Feb. 12th, 1863, but on the same day a second letter waswritten as follows: _1863, Feb. 12_. DEAR SIR, I am extremely ignorant of all matters connected with courtceremonial, and in reference to the proposed Knighthood would askyou:-- 1. I trust that there is no expense of fees. To persons like myself ofsmall fortune an honour may sometimes be somewhat dear. 2. My highest social rank is that given by my Academical Degree ofD. C. L. Which I hold in the Universities of Oxford and Cambridge. Inregard to costume, would it be proper that I should appear in thescarlet gown of that degree? or in the ordinary Court Dress? I am, Dear Sir, Yours very faithfully, G. B. AIRY. _The Right Honourable Sir George C. Lewis, Bart. , &c. &c. &c. _ To this letter Sir G. C. Lewis replied that the fees would amount toabout _£30_, an intimation which produced the following letter: ROYAL OBSERVATORY, GREENWICH, S. E. _1863, Feb. 19th_. DEAR SIR, I have to acknowledge your letter of yesterday: and I advert to thatpart of it in which it is stated that the Fees on Knighthood amount toabout _£30_. Twenty-seven years ago the same rank was offered to me by Lord JohnRussell and Mr Spring Rice (then Ministers of the Crown), with theexpress notice that no fees would be payable. I suppose that the usage(whatever it be) on which that notice was founded still subsists. To a person whose annual income little more than suffices to meet theannual expenses of a very moderate establishment, an unsought honourmay be an incumbrance. It appears, at any rate, opposed to the spiritof such an honour, that it should be loaded with Court Expenses in itsvery creation. I hope that the principle stated in 1835 may serve as precedent onthis occasion. I am, dear Sir, Your very faithful servant, G. B. AIRY. _The Right Honourable Sir G. C. Lewis, Bart. , &c. &c. &c. _ No intimation however was received that the fees would be remitted onthe present occasion, and after consideration the proposed Knighthoodwas declined in the following letter: ROYAL OBSERVATORY, GREENWICH, S. E. _1863, April 15_. DEAR SIR, I have frequently reflected on the proposal made by you of the honourof Knighthood to myself. I am very grateful to you for the favourableopinion which you entertain in regard to my supposed claims to notice, and for the kindness with which you proposed publicly to expressit. But on consideration I am strongly impressed with the feeling thatthe conditions attached by established regulation to the conferring ofsuch an honour would be unacceptable to me, and that the honour itselfwould in reality, under the circumstances of my family-establishmentand in my social position, be an incumbrance to me. And finally I havethought it best most respectfully, and with a full sense of thekindness of yourself and of the Queen's Government towards me, to askthat the proposal might be deferred. There is another direction in which a step might be made, affecting mypersonal position in a smaller degree, but not tending to incommodeme, which I would ask leave to submit to your consideration. It is, the definition of the Rank of the Astronomer Royal. The singularcharacter of the office removes it from ordinary rules of rank, andsometimes may produce a disagreeable contest of opinions. The onlyoffices of similar character corresponding in other conditions to thatof the British Astronomer Royal are those of the Imperial Astronomersat Pulkowa (St Petersburg) and Paris. In Russia, where every rank isclearly defined by that of military grade, the Imperial Astronomer hasthe rank of Major-General. In France, the definition is less precise, but the present Imperial Astronomer has been created (as an attachmentof rank to the office) a Senator of the Empire. I am, dear Sir, Your very faithful servant, G. B. AIRY. _The Rt Hon. Sir George C. Lewis, Bart. , &c. &c. &c. _ Sir G. C. Lewis died before receiving this letter, and the letter wasafterwards forwarded to Lord Palmerston. Some correspondence followedbetween Lord Palmerston and Airy on the subject of attaching adefinite rank to the office of Astronomer Royal, as proposed in theabove letter. But the Home Office (for various reasons set forth)stated that the suggestion could not be complied with, and the wholesubject dropped. 1864 The following remarks are extracted from the Report of the AstronomerRoyal to the Board of Visitors. --"In a very heavy squall whichoccurred in the gale of December 2 of last year, the stay of the loftyiron pillar outside of the Park Rails, which carried our telegraphwires, gave way, and the pillar and the whole system of wiresfell. "--"An important alteration has been made in the MagneticObservatory. For several years past, various plans have been underconsideration for preventing large changes of temperature in the roomwhich contains the magnetic instruments. At length I determined toexcavate a subterraneous room or cellar under the original room. Thework was begun in the last week in January, and in all importantpoints it is now finished. "--"In the late spring, some alarm wasoccasioned by the discovery that the Parliamentary Standard of thePound Weight had become coated with an extraneous substance producedby the decomposition of the lining of the case in which it waspreserved. It was decided immediately to compare it with the threeParliamentary Copies, of which that at the Observatory is one. TheNational Standard was found to be entirely uninjured. "--"On November16 of last year, the Transit Instrument narrowly escaped seriousinjury from an accident. The plate chain which carries the largewestern counterpoise broke. The counterpoise fell upon the pier, destroying the massive gun-metal wheels of the lifting machinery, butwas prevented from falling further by the iron stay of the gas-burnerflue. "--"The Prismatic Spectrum-Apparatus had been completed in1863. Achromatic object-glasses are placed on both sides of the prism, so that each pencil of light through the prism consists of parallelrays; and breadth is given to the spectrum by a cylindrical lens. Thespectral lines are seen straighter than before, and generally it isbelieved that their definition is improved. "--"For observation of thesmall planets, a convention has been made with M. Le Verrier. Fromnew moon to full moon, all the small planets visible to 13h areobserved at the Royal Observatory of Greenwich. From full moon to newmoon, all are observed at the Imperial Observatory of Paris. Therelief gained in this way is very considerable. "--"In determining thevariations in the power of the horizontal-force and vertical-forcemagnets depending on temperature, it was found by experiment that thisdepended materially on whether the magnet was heated by air or bywater, and 'The result of these experiments (with air) is to give acoefficient for temperature correction four or five times as great asthat given by the water-heatings, '"--"With regard to the discordancesof the results of observations of dip-needles, experiments had beenmade with needles whose breadth was in the plane passing through theaxis of rotation, and it appeared that the means of extremediscordances were, for an ordinary needle 11' 45", and for a flatneedle 3' 27", " and the Report continues thus: "After this I need notsay that I consider it certain that the small probable errors whichhave been attributed to ordinary needles are a pure delusion. "--TheReport states that in the various operations connected with the trialsand repairs of chronometers, and the system of time-signalstransmitted to various time-balls and clocks, about one-fourth of thestrength of the Observatory is employed, and it continues thus:"Viewing the close dependence of Nautical Astronomy upon accurateknowledge of time, there is perhaps no department of the Observatorywhich answers more completely to the original utilitarian intentionsof the Founder of the Royal Observatory. "--"With regard to theproposal of time-signals at the Start Point, it appears thatcommunications referring to this proposal had passed between the Boardof Admiralty and the Board of Trade, of which the conclusion was, thatthe Board of Trade possessed no funds applicable to the defraying ofthe expenses attending the execution of the scheme. And the Admiraltydid not at present contemplate the establishment of these time-signalsunder their own authority. "--Amongst other Papers in this year, Airy'sPaper entitled "First Analysis of 177 Magnetic Storms, " &c. , was readbefore the Royal Society. Of private history: "There was the usual visit to Playford in thebeginning of the year. --From June 8th to 23rd I made an excursion withmy son Hubert to the Isle of Man, and the Lake District. --FromSept. 7th to 14th I was on a trip to Cornwall with my two eldest sons, chiefly in the mining district. --In August of this year my eldest(surviving) daughter, Hilda, was married to Mr E. J. Routh, Fellow ofSt Peter's College, Cambridge, at Greenwich Parish Church. Theyafterwards resided at Cambridge. " 1865 "Our telegraphic communications of every kind were again destroyed bya snow-storm and gale of wind which occurred on Jan. 28th, and whichbroke down nearly all the posts between the Royal Observatory and theGreenwich Railway Station. --The Report to the Visitors states that'The only change of Buildings which I contemplate as at presentrequired is the erection of a fire-proof Chronometer Room. Thepecuniary value of Chronometers stored in the Observatory is sometimesperhaps as much as _£8000_. '--The South Eastern and London Chatham andDover scheme for a railway through the Park was again broughtforward. There was a meeting of Sir J. Hanmer's Committee at theObservatory on May 26th. Mr Stone was sent hastily to Dublin to makeobservations on Earth-disturbance by railways there. I had beenbefore the Committee on May 25th. On Sept. 1st I approved of anamended plan. In reference to this matter the Report states that 'Itis proper to remark that the shake of the Altazimuth felt in theearthquake of 1863, Oct. 5th, when no such shake was felt withinstruments nearer to the ground (an experience which, as I have heardon private authority, is supported by observation of artificialtremors), gives reason to fear that, at distances from a railway whichwould sufficiently defend the lower instruments, the loftierinstruments (as the Altazimuth and the Equatoreals) would be sensiblyaffected. '--Some of the Magnets had been suspended by steel wires, instead of silk, of no greater strength than was necessary for safety, and the Report states that 'Under the pressure of business, thedetermination of various constants of adjustment was deferred to theend of the year. The immediate results of observation, however, beganto excite suspicion; and after a time it was found that, in spite ofthe length of the suspending wire (about 8 feet) thetorsion-coefficient was not much less than 1/6. The wires werepromptly dismounted, and silk skeins substituted for them. With these, the torsion-coefficient is about 1/210. '--The Dip-Instrument, whichhad given great trouble by the irregularities of the dip-results, hadbeen compared with two dip-instruments from Kew Observatory, whichgave very good and accordant results. 'It happened that Mr Simms, bywhom our instruments now in use were prepared, and who had personallywitnessed our former difficulties, was present during some of theseexperiments. Our own instrument being placed in his hands (Nov. 10thto 19th) for another purpose, he spontaneously re-polished theapparently faultless agate-bearings. To my great astonishment, theinconsistencies of every kind have nearly or entirely vanished. Onraising and lowering the needles, they return to the same readings, and the dips with the same needle appear generally consistent. ' Somepractical details of the polishing process by which this result hadbeen secured are then given. --After numerous delays, the apparatus forthe self-registration of Spontaneous Earth Currents was brought into aworking state in the month of March. A description of the arrangementadopted is given in the Report. --'All Chronometers on trial are ratedevery day, by comparison with one of the clocks sympathetic with theMotor Clock. Every Chronometer, whether on trial or returned from achronometer-maker as repaired, is tried at least once in the heat ofthe Chronometer-Oven, the temperature being usually limited to 90°Fahrenheit; and, guided by the results of very long experience, wehave established it as a rule, that every trial in heat be continuedthrough three weeks. '--'The only employment extraneous to theObservatory which has occupied any of my time within the last year isthe giving three Lectures on the Magnetism of Iron Ships (at therequest of the Lords of the Committee of Council on Education) in theTheatre of the South Kensington Museum. The preparations, however, for these Lectures, to be given in a room ill-adapted to them, occupied a great deal of my own time, and of the time of an Assistantof the Observatory. '--'Referring to a matter in which the interests ofAstronomy are deeply concerned, I think it right to report to theVisitors my late representation to the Government, to the effect that, in reference to possible observation of the Transit of Venus in 1882, it will be necessary in no long time to examine the coasts of theGreat Southern Continent. '" Of private history: "There were the usual visits to Playford at thebeginning and end of the year. --From June 18th to 26th I was on a tripin Wales with my sons Hubert and Osmund. --From Sept. 6th to Oct. 2nd Iwas staying with most of my family at Portinscale near Keswick: wereturned by Barnard Castle, Rokeby, &c. " CHAPTER VIII. AT GREENWICH OBSERVATORY--1866 TO 1876. 1866 In this year the cube of the Transit Circle was pierced, to permitreciprocal observations of the Collimators without raising theinstrument. This involved the construction of improved Collimators, which formed the subject of a special Address to the Members of theBoard of Visitors on Oct. 21st 1865. --From the Report to the Visitorsit appears that "On May 23rd 1865, a thunderstorm of great violencepassed very close to the Observatory. After one flash of lightning, Iwas convinced that the principal building was struck. Severalgalvanometers in the Magnetic Basement were destroyed. Lately it hasbeen remarked that one of the old chimneys of the principal buildinghad been dislocated and slightly twisted, at a place where it wassurrounded by an iron stay-band led from the Telegraph Pole which wasplanted upon the leads of the Octagon Room. "--"On consideration of theserious interruptions to which we have several times been exposed fromthe destruction of our open-air Park-wires (through snow-storms andgales), I have made an arrangement for leading the whole of our wiresin underground pipes as far as the Greenwich Railway Station. "--"TheCommittee of the House of Commons, to whom the Greenwich and WoolwichLine of the South Eastern Railway was referred, finally assented tothe adoption of a line which I indicated, passing between thebuildings of the Hospital Schools and the public road toWoolwich. "--"The Galvanic Chronometer attached to the S. E. Equatorealoften gave us a great deal of trouble. At last I determined, on theproposal of Mr Ellis, to attempt an extension of Mr R. L. Jones'sregulating principle. It is well known that Mr Jones has with greatsuccess introduced the system of applying galvanic currentsoriginating in the vibrations of a normal pendulum, not to drive thewheelwork of other clocks, but to regulate to exact agreement therates of their pendulums which were, independently, nearly inagreement; each clock being driven by weight-power as before. The sameprinciple is now applied to the chronometer. . . . The construction isperfectly successful; the chronometer remains in coincidence with theTransit Clock through any length of time, with a small constant erroras is required by mechanical theory. "--"The printed volume ofObservations for 1864 has two Appendixes; one containing thecalculations of the value of the Moon's Semi-diameter deduced from 295Occultations observed at Cambridge and Greenwich from 1832 to 1860, and shewing that the Occultation Semi-diameter is less than theTelescopic Semi-diameter by 2"; the other containing the reduction ofthe Planetary Observations made at the Royal Observatory in the years1831-1835; filling up the gap, between the Planetary Reductions1750-1830 made several years ago under my superintendence, and theReductions contained in the Greenwich Volumes 1836 to the presenttime: and conducted on the same general principles. "--"Some troublehad been found in regulating the temperature of the Magnetic Basement, but it was anticipated that in future there would be no difficulty inkeeping down the annual variation within about 5° and the diurnalvariation within 3°. --Longitudes in America were determined in thisyear by way of Valencia and Newfoundland: finished by Nov. 14th. " Of private history: In April he made a short visit to Ventnor in theIsle of Wight. --From June 15th to July 23rd he was on an expedition inNorway with his son Osmund and his nephew Gorell Barnes. --There wasprobably a short stay at Playford in the winter. In this and in the previous year (1865) the free-thinkinginvestigations of Colenso, the Bishop of Natal, had attracted muchnotice, and had procured him the virulent hostility of a numeroussection. His income was withheld from him, and in consequence asubscription fund was raised for his support by his admirers. Airy, who always took the liberal side in such questions, was a subscriberto the fund, and wrote the following letter to the Bishop: ROYAL OBSERVATORY, GREENWICH, S. E. , _1865, July 24_. MY LORD, With many thanks I have to acknowledge your kind recollection of me insending as a presentation copy the work on Joshua, Judges, andespecially on the divided authorship of Genesis; a work whoseinvestigations, founded in great measure on severe and extensiveverbal criticism, will apparently bear comparison with your Lordship'smost remarkable examination of Deuteronomy. I should however not dojustice to my own appreciation if I did not remark that there areother points considered which have long been matters of interest tome. On several matters, some of them important, my present conclusions donot absolutely agree with your Lordship's. But I am not the lessgrateful for the amount of erudition and thought carefully directed todefinite points, and above all for the noble example of unweariedresearch and freedom in stating its consequences, in reference tosubjects which scarcely ever occupy the attention of the clergy in ourcountry. I am, My Lord, Yours very faithfully, G. B. AIRY. _The Lord Bishop of Natal_. * * * * * Here also is a letter on the same subject, written to ProfessorSelwyn, Professor of Divinity at Cambridge:-- ROYAL OBSERVATORY, GREENWICH, LONDON, S. E. , _1866, May 5_. MY DEAR SIR, The MS. Concerning Colenso duly arrived. I note your remarks on the merits of Colenso. I do not write to tellyou that I differ from you, but to tell you why I differ. I think that you do not make the proper distinction between a personwho invents or introduces a tool, and the person who uses it. The most resolute antigravitationist that ever lived might yetacknowledge his debt to Newton for the Method of Prime and UltimateRatios and the Principles of Fluxions by which Newton sought toestablish gravitation. So let it be with Colenso. He has given me a power of tracing outtruth to a certain extent which I never could have obtained withouthim. And for this I am very grateful. As to the further employment of this power, you know that he and I useit to totally different purposes. But not the less do I say that I oweto him a new intellectual power. I quite agree with you, that the sudden disruption of the oldtraditional view seems to have unhinged his mind, and to have sent himtoo far on the other side. I would not give a pin for his judgment. Nevertheless, I wish he would go over the three remaining books of theTetrateuch. I know something of Myers, but I should not have thought him likely toproduce anything sound on such things as the Hebrew Scriptures. Inever saw his "Thoughts. " I am, my dear Sir, Yours very truly, G. B. AIRY. _Professor Selwyn_. * * * * * The following letter has reference to Airy's proposal to introducecertain Physico-Mathematical subjects into the Senate-HouseExamination for B. A. Honors at Cambridge. On various occasions hesharply criticized the Papers set for the Senate-House Examination andthe Smith's Prize Examination, and greatly lamented the growingimportance of pure mathematics and the comparative exclusion ofphysical questions in those examinations. His proposal as finallysubmitted in the letter that follows was somewhat modified (as regardsthe mode of introducing the subjects) from his original draft, indeference to the opinions of Whewell, Adams, Routh, and other friendsto whom he had submitted it. His proposal was favourably received bythe Mathematical Board, and recommendations were made in thedirection, though not to the extent, that he desired, and hesubsequently submitted a Memorandum on those recommendations: ROYAL OBSERVATORY, GREENWICH, _1866, May 11_. MY DEAR SIR, You will perceive, from perusal of the enclosed paper, that I haveacted on the permission which you kindly gave me, to transmit to youmy proposal for extension of the mathematical education of theUniversity in the Physical direction. It is an unavoidable consequence of the structure of the Universitythat studies there will have a tendency to take an unpractical formdepending much on the personal tastes of special examiners. I trustthat, as a person whose long separation from the daily business of theUniversity has enabled him to see in some measure the wants of theexternal scientific and practical world, I may be forgiven thisattempt to bring to the notice of the University my ideas on thepoints towards which their attention might perhaps be advantageouslyturned. I am, my dear Sir, Very faithfully yours, G. B. AIRY. _The Rev. Dr Cartmell, Master of Christ's College and Vice-Chancellor. _ ROYAL OBSERVATORY, GREENWICH, _1866, May 11_. MY DEAR MR VICE-CHANCELLOR, About two years ago, by the kindness of the University, an opportunitywas presented to me of orally stating what I conceived to bedeficiencies in the educational course of the University as regardsmathematical physics. Since that time, the consideration of thosedeficiencies, which had long been present to me, has urged itself onmy attention with greater force: and finally I have entertained theidea that I might without impropriety communicate to you my opinion, in a less fugitive form than on the occasion to which I have alluded:with the request that, if you should deem such a course appropriate, you would bring it before the Board of Mathematical Studies, andperhaps ultimately make it known to the Resident Members of theSenate. I will first give the list of subjects, which I should wish to seeintroduced, and to the prosecution of which the generally admirablecourse of the University is remarkably well adapted: and I will then, without entering into every detail, advert to the process by which Ithink it probable the introduction of these subjects could beeffected. In the following list, the first head is purely algebraical, and thesecond nearly so: but they are closely related to observationalscience, and to the physical subjects which follow. Some of thesubjects which I exhibit on my list are partially, but in my opinionimperfectly, taught at present. I entirely omit from my list PhysicalOptics, Geometrical Astronomy, and Gravitational Astronomy of Points:because, to the extent to which Academical Education ought to go, Ibelieve that there is no teaching on these sciences comparable to thatin the University of Cambridge. (It is, of course, still possible thatimprovements may be made in the books commonly used. ) It might, however, be a question, whether, as regards the time and manner ofteaching them, some parts of these subjects might ultimately beassociated with the other subjects included in my list. I. _List of subjects proposed for consideration_. (1) Partial Differential Equations to the second order, with theirarbitrary functions: selected principally with reference to thephysical subjects. (2) The Theory of Probabilities as applied to the combination ofObservations. (3) Mechanics (including Hydraulic Powers) in the state which vergesupon practical application, and especially including that part inwhich the abstract ideas of _power_ and _duty_ occur. (4) Attractions. This subject is recognized in the existing course ofthe University: but, so far as I can infer from examination-papers, itappears to be very lightly passed over. (5) The Figure of the Earth, and its consequences, Precession, &c. Ibelieve that the proposal is sanctioned, of adopting some part of thistheory in the ordinary course; but perhaps hardly so far as isdesirable. (6) The Tides. (7) Waves of Water. (8) Sound (beginning with Newton's investigation); Echoes; Pipes andVibrating Strings; Acoustics; the Mathematical part of Music. (9) Magnetism, terrestrial and experimental, and their connection. (I omit for the present Mineralogy and Mathematical Electricity. ) This list of subjects appears formidable: but they are in realityeasy, and would be mastered in a short time by the higher Wranglers. II. _Mode of introducing these subjects into the University_. After much consideration, and after learning the opinions of severalpersons whose judgment claims my deepest respect, I propose thegradual introduction of these subjects into the Examination for Honorsat admission to the B. A. Degree, as soon as the preparation of Booksand the readiness of Examiners shall enable the University to takethat step. I conceive that, by a judicious pruning of the somewhatluxuriant growth of Pure Algebra, Analytical Geometry, and MereProblems, sufficient leisure may be gained for the studies of theundergraduates, and sufficient time for the questions of theexaminers. I do not contemplate that the students could advance veryfar into the subjects; but I know the importance of beginning them;and, judging from the train of thoughts, of reading, and ofconversation, among the Bachelors with whom I associated many yearsago, I believe that there is quite a sufficient number who will beanxious to go deep into the subjects if they have once entered intothem. If six Wranglers annually would take them up, my point would begained. The part which these gentlemen might be expected, in a shorttime, to take in the government of the University, would enable themsoon to act steadily upon the University course: the efficiency of theUniversity instruction would be increased; and the external characterof the University would be raised. The real difficulties, and they are not light ones, would probably befound in providing Examiners and Books. At present, both are wantingwithin the University. Where there is a great and well-foundedobjection to intrusting examinations to persons foreign to theUniversity, and where the books have to be created with labour andwith absolute outlay of money (for their sale could never beremunerative), the progress must be slow. Still progress would becertain, if the authorities of the University should think the matterdeserving of their hearty encouragement. Requesting that you and the Members of the University will accept thisproposal as an indication of my deep attachment to my University, I am, My dear Mr Vice-Chancellor, Your very faithful servant, G. B. AIRY. _The Rev. Dr Cartmell, &c. &c. Vice-Chancellor of the University of Cambridge_. 1867 "In this year it was arranged that my Treasury accounts were to betransferred to the Admiralty, making the simplification which I had solong desired. --From the Report to the Visitors it appears that a relicof the Geodetic operations commenced in 1787 for connecting theObservatories of Greenwich and Paris, in the shape of an observingcabin on the roof of the Octagon Room, was shifted and supported insuch a manner that the pressure on the flat roof was entirelyavoided. --With regard to the Transit Circle, the new Collimators withtelescopes of seven inches aperture had been mounted. When the TransitTelescope directed vertically is interposed, the interruptions in thecentral cube impair the sharpness of definition, still leaving itabundantly good for general use. It had been regarded as probable thatthe astronomical flexure of the telescope, after cutting away smallportions of the central cube, would be found sensibly changed: andthis proved to be the case. The difference of flexures of the two endshas been altered more than a second of arc. --Referring to a newPortable Altazimuth which had lately been tested, the Report states asfollows: 'I may mention that a study of defects in the vertical circleof a small Altazimuth formerly used by me, and an inspection of theoperations in the instrument-maker's work-shop, have convinced me thatthe principal error to be feared in instruments of this class isovality of the graduated limb; this cannot be eliminated by twomicroscopes, and such an instrument should never be fitted with twoonly. Our instrument has four. '--'In Osler's Anemometer, a surface of2 square feet is now exposed to the wind instead of one foot asformerly; and the plate is supported by weak vertical springs insteadof rods running on rollers. Its indications are much more delicatethan formerly. '--'The Meteors on Nov. 14th were well observed. Eightthousand and three hundred were registered. The variations offrequency at different times were very well noted. The points ofdivergence were carefully determined. '--Referring to the gradualimprovement in the steadiness of chronometers from 1851 to 1866, itappears that from 1851 to 1854 the 'trial number' (which is acombination of changes of weekly rate representing the fault of thechronometer) varied from 34. 8s to 52. 5s, while from 1862 to 1866 itvaried from 21. 2s to 25. 8s. --The following statement will shew theusual steadiness of the Great Clock on the Westminster Palace: On 38per cent. Of days of observation, the clock's error was below 1s. On38 per cent, the error was between 1s and 2s. On 21 per cent. It wasbetween 2s and 3s. On 2 per cent. Between 3s and 4s. On 1 per cent. Between 4s and 5s. --The Report contains an account of thedetermination of the longitude of Cambridge U. S. By Dr B. A. Gould, bymeans of galvanic currents through the Atlantic Cable, in the springof 1867: and advantage was taken of this opportunity forre-determining the longitude of Feagh Main near Valencia inIreland. The longitude of Feagh Main, found by different methods is asfollows: By chronometers in 1844, 41m 23. 23s; by galvaniccommunication with Knight's Town in 1862, 41m 23. 37s; by galvaniccommunication with Foilhommerum in 1866, 41m 23. 19s. The collectedresults for longitude of Cambridge U. S. From different sources are: Bymoon-culminators (Walker in 1851, and Newcomb in 1862-3), 4h 44m28. 42s and 4h 44m 29. 56s respectively; by Eclipses (Walker in 1851), 4h 44m 29. 64s; by occultations of Pleiades (Peirce 1838-1842, and1856-1861), 4h 44m 29. 91s and 4h 44m 30. 90s respectively; bychronometers (W. C. Bond in 1851, and G. P. Bond in 1855), 4h 44m30. 66s and 4h 44m 31. 89s respectively; by Atlantic Cable 1866, 4h 44m30. 99s. --After noticing that many meteorological observatories hadsuddenly sprung up and had commenced printing their observations indetail, the Report continues thus: 'Whether the effect of thismovement will be that millions of useless observations will be addedto the millions that already exist, or whether something may beexpected to result which will lead to a meteorological theory, Icannot hazard a conjecture. This only I believe, that it will beuseless, at present, to attempt a process of mechanical theory; andthat all that can be done must be, to connect phenomena by laws ofinduction. But the induction must be carried out by numerous andtroublesome trials in different directions, the greater part of whichwould probably be failures. '--There was this year an annular eclipse;I made large preparations at the limits of the annularity; failedentirely from very bad weather. "--In this year Airy contributed aPaper to the Institution of Civil Engineers 'On the use of theSuspension Bridge with stiffened roadway for Railway and other Bridgesof Great Span, ' for which a Telford Medal was awarded to him by theCouncil of the Institution. And he communicated several Papers to theRoyal Society and the Royal Astronomical Society. Of private history: There was the usual visit to Playford inJanuary. --In April there was a short run to Alnwick and theneighbourhood, in company with Mr and Mrs Routh. --From June 27th toJuly 4th he was in Wales with his two eldest sons, visiting Uriconium, &c. On his return. --From August 8th to Sept. 7th he spent a holiday inScotland and the Lake District of Cumberland with his daughterChristabel, visiting the Langtons at Barrow House, near Keswick, andIsaac Fletcher at Tarn Bank. In June of this year (1867) Airy was elected an Honorary Fellow of hisold College of Trinity in company with Connop Thirlwall, the Bishop ofSt David's. They were the first Honorary Fellows elected by theCollege. The announcement was made in a letter from the Master ofTrinity (W. H. Thompson), and Airy's reply was as follows: ROYAL OBSERVATORY, GREENWICH, LONDON, S. E. _1867, June 12th_. MY DEAR MASTER, I am very much gratified by your kind note received this morning, conveying to me the notice that the Master and Sixteen Senior Fellowshad elected me, under their new powers, as Honorary Fellow of theCollege. It has always been my wish to maintain a friendly connection with myCollege, and I am delighted to receive this response from theCollege. The peculiar form in which the reference to the Statuteenables them to put it renders it doubly pleasing. As the Statute is new, I should be obliged by a copy of it. And, atany convenient time, I should be glad to know the name of the personwith whom I am so honorably associated. I am, My dear Master, Very faithfully yours, G. B. AIRY. * * * * * Consequent on Airy's proposals in 1866 for the introduction of newphysical subjects into the Senate-House Examination and his desirethat the large number of questions set in Pure Mathematics, or as hetermed it "Useless Algebra, " should be curtailed, there was a smartand interesting correspondence between him and Prof. Cayley, who wasthe great exponent and advocate of Pure Mathematics at Cambridge. Bothof them were men of the highest mathematical powers, but diametricallyopposed in their views of the use of Mathematics. Airy regardedmathematics as simply a useful machine for the solution of practicalproblems and arriving at practical results. He had a great respect forPure Mathematics and all the processes of algebra, so far as theyaided him to solve his problems and to arrive at useful results; buthe had a positive aversion to mathematical investigations, howeverskilful and elaborate, for which no immediate practical value could beclaimed. Cayley on the contrary regarded mathematics as a usefulexercise for the mind, apart from any immediate practical object, andhe considered that the general command of mathematics gained byhandling abstruse mathematical investigations (though barren inthemselves) would be valuable for whatever purpose mathematics mightbe required: he also thought it likely that his researches andadvances in the field of Pure Mathematics might facilitate thesolution of physical problems and tend to the progress of thepractical sciences. Their different views on this subject will beseen from the letters that follow: ROYAL OBSERVATORY, GREENWICH, LONDON, S. E. _1867, Nov. 8_. MY DEAR SIR, I think it best to put in writing the purport of what I have said, orhave intended to say, in reference to the Mathematical Studies in theUniversity. First, I will remark on the study of Partial Differential Equations. I do not know that one branch of Pure Mathematics can be consideredhigher than another, except in the utility of the power which itgives. Measured thus, the Partial Differential Equations are veryuseful and therefore stand very high, as far as the Second Order. They apply, to that point, in the most important way, to the greatproblems of nature concerning _time_, and _infinite division ofmatter_, and _space_: and are worthy of the most careful study. Beyondthat Order they apply to nothing. It was for the purpose of limitingthe study to the Second Order, and at the same time working itcarefully, philosophically, and practically, up to that point, that Idrew up my little work. On the general question of Mathematical Studies, I will first give myleading ideas on what I may call the moral part. I think that a heavyresponsibility rests on the persons who influence most strongly thecourse of education in the University, to direct that course in theway in which it will be most useful to the students--in the two ways, of disciplining their powers and habits, and of giving them scientificknowledge of the highest and most accurate order (applying to thephenomena of nature) such as will be useful to them through life. I donot think that the mere personal taste of a teacher is sufficientjustification for a special course, unless it has been adopted under aconsideration of that responsibility. Now I can say for myself that Ihave, for some years, inspected the examination papers, and haveconsidered the bearing of the course which they imply upon theeducation of the student, and am firmly convinced that as regards menbelow the very few first--say below the ten first--there is aprodigious loss of time without any permanent good whatever. For thegreat majority of men, such subjects as abstract Analytical Geometryperish at once. With men like Adams and Stokes they remain, and areadvantageous; but probably there is not a single man (beside them) oftheir respective years who remembers a bit, or who if he remembersthem has the leisure and other opportunities of applying them. I believe on the other hand that a careful selection of physicalsubjects would enable the University to communicate to its students avast amount of information; of accurate kind and requiring the mostlogical treatment; but so bearing upon the natural phenomena which areconstantly before us that it would be felt by every student to possessa real value, that (from that circumstance) it would dwell in hismind, and that it would enable him to correct a great amount of flimsyeducation in the country, and, so far, to raise the nationalcharacter. The consideration of the education of the reasoning habits suggestsideas far from favourable to the existing course. I am old enough toremember the time of mere geometrical processes, and I do not hesitateto say that for the cultivation of accurate mental discipline theywere far superior to the operations in vogue at the present day. Thereis no subject in the world more favourable to logical habit than theDifferential Calculus in all its branches _if logically worked in itselements_: and I think that its applications to various physicalsubjects, compelling from time to time an attention to the elementarygrounds of the Calculus, would be far more advantageous to thatlogical habit than the simple applications to Pure Equations and PureAlgebraical Geometry now occupying so much attention. I am, my dear Sir, Yours very truly, G. B. AIRY. _Professor Cayley_. * * * * * DEAR SIR, I have been intending to answer your letter of the 8th November. Sofar as it is (if at all) personal to myself, I would remark that thestatutory duty of the Sadlerian Professor is that he shall explain andteach the principles of Pure Mathematics and apply himself to theadvancement of the Science. As to Partial Differential Equations, they are "high" as being aninverse problem, and perhaps the most difficult inverse problem thathas been dealt with. In regard to the limitation of them to the secondorder, whatever other reasons exist for it, there is also the reasonthat the theory to this order is as yet so incomplete that there is noinducement to go beyond it; there could hardly be a more valuable stepthan anything which would give a notion of the form of the generalintegral of a Partial Differential Equation of the second order. I cannot but differ from you _in toto_ as to the educational value ofAnalytical Geometry, or I would rather say of Modern Geometrygenerally. It appears to me that in the Physical Sciences depending onPartial Differential Equations, there is scarcely anything that astudent can do for himself:--he finds the integral of the ordinaryequation for Sound--if he wishes to go a step further and integratethe non-linear equation (dy/dx)²(d²y/dt²) = a²(d²y/dx²) he is simplyunable to do so; and so in other cases there is nothing that he canadd to what he finds in his books. Whereas Geometry (of course to anintelligent student) is a real inductive and deductive science ofinexhaustible extent, in which he can experiment for himself--the verytracing of a curve from its equation (and still more the considerationof the cases belonging to different values of the parameters) is theconstruction of a theory to bind together the facts--and the selectionof a curve or surface proper for the verification of any generaltheorem is the selection of an experiment in proof or disproof of atheory. I do not quite understand your reference to Stokes and Adams, as typesof the men who alone retain their abstract Analytical Geometry. If aman when he takes his degree drops mathematics, he drops geometry--butif not I think for the above reasons that he is more likely to go onwith it than with almost any other subject--and any mathematicaljournal will shew that a very great amount of attention is in factgiven to geometry. And the subject is in a very high degree aprogressive one; quite as much as to Physics, one may apply to it thelines, Yet I doubt not thro' the ages one increasing purpose runs, andthe thoughts of men are widened with the progress of the suns. I remain, dear Sir, Yours very sincerely, A. CAYLEY. CAMBRIDGE, _6 Dec. , 1867_. * * * * * ROYAL OBSERVATORY, GREENWICH, LONDON, S. E. _1867, December 9_. MY DEAR SIR, I have received with much pleasure your letter of December 6. In thisUniversity discussion, I have acted only in public, and have not madeprivate communication to any person whatever till required to do so byprivate letter addressed to me. Your few words in Queens' Hall seemedto expect a little reply. Now as to the Modern Geometry. With your praises of this science--asto the room for extension in induction and deduction, &c. ; and withyour facts--as to the amount of space which it occupies inMathematical Journals; I entirely agree. And if men, after leavingCambridge, were designed to shut themselves up in a cavern, they couldhave nothing better for their subjective amusement. They might haveother things as good; enormous complication and probably beautifulinvestigation might be found in varying the game of billiards withnovel islands on a newly shaped billiard table. But the persons whodevote themselves to these subjects do thereby separate themselvesfrom the world. They make no step towards natural science orutilitarian science, the two subjects which the world speciallydesires. The world could go on as well without these separatists. Now if these persons lived only for themselves, no other person wouldhave any title to question or remark on their devotion to this barrensubject. But a Cambridge Examiner is not in that position. TheUniversity is a national body, for education of young men: and thepower of a Cambridge Examiner is omnipotent in directing the educationof the young men; and his responsibility to the cause of education isvery distinct and very strong. And the question for him to consideris--in the sense in which mathematical education is desired by thebest authorities in the nation, is the course taken by this nationalinstitution satisfactory to the nation? I express my belief that it is _not_ satisfactory. I believe that manyof the best men of the nation consider that a great deal of time islost on subjects which they esteem as puerile, and that much of thattime might be employed on noble and useful science. You may remember that the Commissions which have visited Cambridgeoriginated in a Memorial addressed to the Government by men ofrespected scientific character: Sabine was one, and I may take him asthe representative. He is a man of extensive knowledge of theapplication of mathematics as it has been employed for many years inthe science of the world; but he has no profundity of science. He, asI believe, desired to find persons who could enter accurately intomathematical science, and naturally looked to the Great MathematicalUniversity; but he must have been much disappointed. So much time isswallowed up by the forced study of the Pure Mathematics that it isnot easy to find anybody who can really enter on these subjects inwhich men of science want assistance. And so Sabine thought that theGovernment ought to interfere, probably without any clear idea of whatthey could do. I am, my dear Sir, Yours very truly, G. B. AIRY. _Professor Cayley_. * * * * * DEAR SIR, I have to thank you for your last letter. I do not think everythingshould be subordinated to the educational element: my idea of aUniversity is that of a place for the cultivation of allscience. Therefore among other sciences Pure Mathematics; includingwhatever is interesting as part of this science. I am bound thereforeto admit that your proposed extension of the problem of billiards, _ifit_ were found susceptible of interesting mathematical developments, would be a fit subject of study. But in this case I do not think theproblem could fairly be objected to as puerile--a more legitimateobjection would I conceive be its extreme speciality. But this is notan objection that can be brought against Modern Geometry as a whole:in regard to any particular parts of it which may appear open to suchan objection, the question is whether they are or are not, for theirown sakes, or their bearing upon other parts of the science to whichthey belong, worthy of being entered upon and pursued. But admitting (as I do not) that Pure Mathematics are only to bestudied with a view to Natural and Physical Science, the questionstill arises how are they best to be studied in that view. I assumeand admit that as to a large part of Modern Geometry and of the Theoryof Numbers, there is no present probability that these will find anyphysical applications. But among the remaining parts of PureMathematics we have the theory of Elliptic Functions and of theJacobian and Abelian Functions, and the theory of DifferentialEquations, including of course Partial Differential Equations. Nowtaking for instance the problem of three bodies--unless this is to begone on with by the mere improvement in detail of the presentapproximate methods--it is at least conceivable that the futuretreatment of it will be in the direction of the problem of two fixedcentres, by means of elliptic functions, &c. ; and that the discoverywill be made not by searching for it directly with the mathematicalresources now at our command, but by "prospecting" for it in the fieldof these functions. Even improvements in the existing methods are morelikely to arise from a study of differential equations in general thanfrom a special one of the equations of the particular problem: thematerials for such improvements which exist in the writings ofHamilton, Jacobi, Bertrand, and Bour, have certainly so arisen. Andthe like remarks would apply to the physical problems which depend onPartial Differential Equations. I think that the course of mathematical study at the University islikely to be a better one if regulated with a view to the cultivationof Science, as if for its own sake, rather than directly uponconsiderations of what is educationally best (I mean that the besteducational course will be so obtained), and that we have thus ajustification for a thorough study of Pure Mathematics. In my ownlimited experience of examinations, the fault which I find with themen is a want of analytical power, and that whatever else may havebeen in defect Pure Mathematics has certainly not been in excess. I remain, dear Sir, Yours sincerely, A. CAYLEY. CAMBRIDGE, _10th Dec. , 1867_. * * * * * _1867, December 17_. MY DEAR SIR, Since receiving your letter of 9th I positively have not had time toexpress the single remark which I proposed to make on it. You state your idea that the educational element ought not to be thepredominating element in the University. "I do not think that everything should be subordinated to the educational element. " I cannotconceal my surprise at this sentiment. Assuredly the founders of theColleges intended them for education (so far as they apply to personsin statu pupillari), the statutes of the University and the Collegesare framed for education, and fathers send their sons to theUniversity for education. If I had not had your words before me, Ishould have said that it is impossible to doubt this. It is much to be desired that Professors and others who exercise nocontrol by force should take every method, not only of promotingscience in themselves, but also of placing the promoted science beforestudents: and it is much to be desired that students who have passedthe compulsory curriculum should be encouraged to proceed into thenovelties which will be most agreeable to them. But this is a totallydifferent thing from using the Compulsory Force of Examination todrive students in paths traced only by the taste of the examiner. Forthem, I conceive the obligation to the nation and the duty to followthe national sense on education (as far as it can be gathered from itsbest representatives) to be undoubted; and to be, in the intensity ofthe obligation and duty, most serious. I am, my dear Sir, Yours very truly, G. B. AIRY. _Professor Cayley_. * * * * * 1868 "In the South-East Dome, the alteration proposed last year forrendering the building fire-proof had been completely carried out. Themiddle room, which was to be appropriated to Chronometers, was beingfitted up accordingly. --From the Report it appears that 'oursubterranean telegraph wires were all broken by one blow, from anaccident in the Metropolitan Drainage Works on Groom's Hill, but werespeedily repaired. '--In my office as Chairman of successiveCommissions on Standards, I had collected a number of Standards, someof great historical value (as Ramsden's and Roy's Standards of Length, Kater's Scale-beam for weighing great weights, and others), &c. Thesehave been transferred to the newly-created Standards Department of theBoard of Trade. "--In the Report is given a detailed account of thesystem of preserving and arranging the manuscripts and correspondenceof the Observatory, which was always regarded by Airy as a matter ofthe first importance. --From a careful discussion of the results ofobservation Mr Stone had concluded that the refractions ought to bediminished. 'Relying on this, we have now computed our meanrefractions by diminishing those of Bessel's Fundamenta in theproportion of 1 to 0. 99797. '--The Magnetometer-Indications for theperiod 1858-1863 had been reduced and discussed, with remarkableresults. It is inferred that magnetic disturbances, both solar andlunar, are produced mediately by the Earth, and that the Earth inperiods of several years undergoes changes which fit it and unfit itfor exercising a powerful mediate action. --The Earth-current recordshad been reduced, and the magnetic effect which the currents wouldproduce had been computed. The result was, that the agreement betweenthe magnetic effects so computed and the magnetic disturbances reallyrecorded by the magnetometers was such as to leave no doubt on thegeneral validity of the explanation of the great storm-disturbances ofthe magnets as consequences of the galvanic currents through theearth. --Referring to the difficulty experienced in making themeteorological observations practically available the Report statesthus: 'The want of Meteorology, at the present time, is principally insuggestive theory. '--In this year Airy communicated to the RoyalAstronomical Society a Paper 'On the Preparatory Arrangements for theObservation of the Transits of Venus 1874 and 1882': this subject wasnow well in hand. --The First Report of the Commissioners (of whom hewas Chairman) appointed to enquire into the condition of the ExchequerStandards was printed: this business took up much time. --He was inthis year much engaged on the Coinage Commission. Of private history: There was the usual winter visit to Playford, anda short visit to Cambridge in June. --From about Aug. 1st to Sept. 3rdhe was travelling in Switzerland with his youngest son and his twoyoungest daughters. In the course of this journey they visitedZermatt. There had been much rain, the rivers were greatly flooded, and much mischief was done to the roads. During the journey from Vispto Zermatt, near St Nicholas, in a steep part of the gorge, a largestone rolled from the cliffs and knocked their baggage horse over thelower precipice, a fall of several hundred feet. The packages were allburst, and many things were lost, but a good deal was recovered by mensuspended by ropes. In this year also Airy was busy with the subject of UniversityExamination, which in previous years had occupied so much of hisattention, as will be seen from the following letters: ROYAL OBSERVATORY, GREENWICH, LONDON, S. E. _1868, March 12_. MY DEAR MASTER, I have had the pleasure of corresponding with you on matters ofUniversity Examination so frequently that I at once turn to you as theproper person to whom I may address any remarks on that importantsubject. Circumstances have enabled me lately to obtain private information ofa most accurate kind on the late Mathematical Tripos: and among otherthings, I have received a statement of every individual questionanswered or partly answered by five honour-men. I have collected thenumbers of these in a small table which I enclose. I am struck with the _almost_ nugatory character of the five days'honour examination as applied to Senior Optimes, and I do not doubtthat it is _totally_ nugatory as applied to Junior Optimes. It appearsto me that, for all that depends on these days, the rank of theOptimes is mere matter of chance. In the examinations of the Civil Service, the whole number of marks ispublished, and also the number of marks gained by each candidate. Ihave none of their papers at hand, but my impression is that thelowest candidates make about 1 in 3; and the fair candidates about 2in 3, instead of 1 in 10 or 1 in 13 as our good Senior Optimes. I am, my dear Master, Very truly yours, G. B. AIRY. _The Rev. Dr Cookson, Master of St Peters College, &c. &c. _ The Table referred to in the above letter is as follows: Number of Questions, and numbers of Answers to Questions as given byseveral Wranglers and Senior Optimes, in the Examination ofMathematical Tripos for Honours, 1868, January 13, 14, 15, 16, 17. Number of Questions and Riders in the Printed Papers. Questions. Riders. Aggregate. In the 10 Papers of the 5 days 123 101 224 NUMBER OF QUESTIONS AND RIDERS ANSWERED. Questions. Riders. Aggregate. By a Wrangler, between the 1st and 7th 69-1/2 25-1/2 95 1 in 2. 36 By a Wrangler, between the 12th and 22nd 48-1/2 12-1/2 61 1 in 3. 68 By a Wrangler, between the 22nd and 32nd 36 12-1/2 48-1/2 1 in 4. 62 By a Sen. Opt. Between the 1st and 10th 17-1/2 5 22-1/2 1 in 9. 95 By a Sen. Opt. Between the 10th and 20th 14-1/2 2 16-1/2 1 in 3. 60 G. B. AIRY. _1868, March 12_. * * * * * ST PETER'S COLLEGE LODGE, CAMBRIDGE, _March 13th, 1868_. MY DEAR SIR, I am much obliged by your letter and enclosed paper. Anything done in the last five days by a Junior Optime only shews(generally) that he has been employing some of his time_mischievously_, for he must have been working at subjects which he isquite unable to master or cramming them by heart on the chance ofmeeting with a stray question which he may answer. The chief part of the Senior Optimes are in something of the samesituation. I think that the proposed addition of a day to the first part of theExamination, in which "easy questions in physical subjects" may beset, is, on this account, a great improvement. Our new Scheme comes on for discussion on Friday next, March 20, at 2p. M. In the Arts School. It is much opposed by private tutors, examiners and others, and may possibly be thrown out in the Senatethis year, though I hope that with a little patience it may becarried, in an unmutilated form, eventually. The enclosed Report on the Smith's Prize Examination will be discussedat the same time. I will consider what is best to be done on the subject to which yournote refers, without delay. With many thanks, I am, Very faithfully yours, H. W. COOKSON, _The Astronomer Royal. _ * * * * * In this year certain Members of the Senate of the University ofCambridge petitioned Parliament against the abolition of religiousdeclarations required of persons admitted to Fellowships or proceedingto the degree of M. A. The document was sent to Airy for his signature, and his reply was as follows: ROYAL OBSERVATORY, GREENWICH, LONDON, S. E. _1868, March 18_. MY DEAR SIR, Though I sympathize to a great extent with the prayer of the petitionto Parliament which you sent to me yesterday, and assent to most ofthe reasons, I do not attach my signature to it, for the followingconsiderations: 1. I understand, from the introductory clause, and from theunqualified character of the phrase "any such measures" in the secondclause, that the petition objects to granting the M. A. Degree withoutreligious declaration. I do not see any adequate necessity for thisobjection, and I cannot join in it. 2. It appears to me that the Colleges were intended for two collateralobjects:--instruction by part of the Fellows, on a religious basis;and support of certain Fellows for scientific purposes, without thesame ostentatious connection with religion. I like this spirit well, and should be glad to maintain it. 3. I therefore think (as I have publicly stated before) that theMaster of the College ought to be in holy orders; and so ought thoseof the Fellows who may be expected to be usually resident and to takecontinuous part in the instruction. But there are many who, upontaking a fellowship, at once lay aside all thoughts of this: and Ithink that such persons ought not to be trammelled with declarations. 4. My modification of existing regulations, if it once got into shape, would I dare say be but a small fraction of that proposed by the"measures in contemplation. " Still I do not like to join inunqualified resistance to interference in the affairs of theEstablished Colleges, with that generality of opposition tointerference which the petition seems to intimate. I agree with articles 3, 4, and 5; and I am pleased with the gracefulallusion in article 4 to the assistance which has been rendered by theColleges, and by none perhaps so honourably as Trinity, to theparishes connected with it. And I could much wish that the spirit of 3and 5 could be carried out, with some concession to my ideas in _my_paragraph 3, above. I am, my dear Sir, Yours very truly, G. B. AIRY. _Rev. Dr Lightfoot. _ * * * * * 1869 From the Report to the Board of Visitors it appears that applicationhad been made for an extension of the grounds of the Observatory to adistance of 100 feet south of the Magnetic Ground, and that a Warrantfor the annexation of this space was signed on 1868, Dec. 8. The newDepôt for the Printed Productions of the Observatory had beentransferred to its position in the new ground, and the foundations forthe Great Shed were completed. --"The courses of our wires for theregistration of spontaneous terrestrial galvanic currents have beenentirely changed. The lines to Croydon and Deptford are abandoned; andfor these are substituted, a line from Angerstein Wharf to Lady WellStation, and a line from North Kent Junction to Morden CollegeTunnel. At each of these points the communication with Earth is madeby a copper plate 2 feet square. The straight line connecting theextreme points of the first station intersects that connecting the twopoints of the second station, nearly at right angles, and at littledistance from the Observatory. --The question of dependence of themeasurable amount of sidereal aberration upon the thickness of glassor other transparent material in the telescope (a question whichinvolves, theoretically, one of the most delicate points in theUndulatory Theory of Light) has lately been agitated on the Continentwith much earnestness. I have calculated the curvatures of the lensesof crown and flint glass (the flint being exterior) for correctingspherical and chromatic aberration in a telescope whose tube is filledwith water, and have instructed Mr Simms to proceed with thepreparation of an instrument carrying such a telescope. I have notfinally decided whether to rely on Zenith-distances of gamma Draconisor on right-ascensions of Polaris. In any form the experiment willprobably be troublesome. --The transit of Mercury on 1868, Nov. 4th, was observed by six observers. The atmospheric conditions werefavourable; and the singular appearances usually presented in aplanetary transit were well seen. --Mr Stone has attached to theSouth-East Equatoreal a thermo-multiplier, with the view of examiningwhether heat radiating from the principal stars can be made sensiblein our instruments. The results hitherto obtained are encouraging, butthey shew clearly that it is vain to attempt this enquiry except inthe most superb weather; and there has not been a night deserving thatepithet for some months past. --The preparations for observing theTransits of Venus were now begun in earnest. I had come to theconclusion, that after every reliance was placed on foreign andcolonial observatories, it would be necessary for the BritishGovernment to undertake the equipment of five or six temporarystations. On Feb. 15th I sent a pamphlet on the subject to Mr Childers(First Lord of Admiralty), and in April I wrote to the Secretary, asking authority for the purchase of instruments. On June 22ndauthority is given to me for the instruments: the Treasury assent to_£10, 500_. On August 9th I had purchased 3 equatoreals. --I have givena short course of Lectures in the University of Cambridge on thesubject of Magnetism, with the view of introducing that importantphysical science into the studies of the University. The want of booksavailable to Students, and the novelty of the subject, made thepreparation more laborious than the duration of the lectures wouldseem to imply. "--In this year there was much work on the StandardsCommission, chiefly regarding the suggested abolition of Troy Weight, and several Papers on the subject were prepared by Airy. --He alsowrote a long and careful description of the Great Equatoreal atGreenwich. Of private history: There was the usual visit to Playford in thewinter. Mrs Airy was now becoming feebler, and did not now leaveGreenwich: since April of this year her letters were written inpencil, and with difficulty, but she still made great efforts to keepup the accustomed correspondence. --In April Airy went to Cambridge todeliver his lectures on magnetism to the undergraduates: the followingpassage occurs in one of his letters at this time: "I have a mightyattendance (there were 147 names on my board yesterday), and, thoughthe room is large with plenty of benches, I have been obliged to bringin some chairs. The men are exceedingly attentive, and when I look upI am quite struck to see the number of faces staring into mine. I goat 12, and find men at the room copying from my big papers: I lecturefrom 1 to 2, and stop till after 3, and through the last hour some menare talking to me and others are copying from the papers; and Iusually leave some men still at work. The men applaud and shew theirrespect very gracefully. There are present some two or three personswho attended my former lectures, and they say that I lecture exactlyas I did formerly. One of my attendants is a man that they say cannot, from years and infirmity and habit, be induced to go anywhere else: DrArchdall, the Master of Emmanuel. I find that some of my oldlecturing habits come again on me. I drink a great deal of cold water, and am very glad to go to bed early. "--From June 10th-30th he wastravelling in Scotland, and staying at Barrow House near Keswick (theresidence of Mr Langton), with his son Hubert. --Subsequently, fromAug. 17th to 31st, he was again in the Lake District, with hisdaughter Christabel, and was joined there by his son Hubert on the24th. The first part of the time was spent at Tarn Bank, nearCarlisle, the residence of Mr Isaac Fletcher, M. P. From thence he madeseveral expeditions, especially to Barrow in Furness and Seascale, where he witnessed with great interest the Bessemer process of makingsteel. From Barrow House he made continual excursions among theCumberland mountains, which he knew so well. 1870 "In this year Mr Stone, the First Assistant, was appointed to the Capeof Good Hope Observatory, and resigned his post of First Assistant. MrChristie was appointed in his place. --From the Report to the Visitorsit appears that 'A few months since we were annoyed by a failure inthe illumination of the field of view of the Transit Circle. Thereflector was cleaned, but in vain; at last it was discovered that oneof the lenses (the convex lens) of the combination which forms theobject-glass of a Reversed Telescope in the interior of theTransit-axis, and through which all illuminating light must pass, hadbecome so corroded as to be almost opaque. '--The South-East Equatorealhas been partly occupied with the thermo-multiplier employed by MrStone for the measure of heat radiating from the principal stars. MrStone's results for the radiation from Arcturus and alpha Lyrae appearto be incontrovertible, and to give bases for distinct numericalestimation of the radiant heat of these stars. --In my last Report Ialluded to a proposed systematic reduction of the meteorologicalobservations during the whole time of their efficientself-registration. Having received from the Admiralty the fundsnecessary for immediate operations, I have commenced with thephotographic registers of the thermometers, dry-bulb and wet-bulb, from 1848 to 1868. --Our chronometer-room contains at present 219chronometers, including 37 chronometers which have been placed here bychronometer-makers as competing for the honorary reputation and thepecuniary advantages to be derived from success in the half-year'strial to which they are subjected. I take this opportunity of statingthat I have uniformly advocated the policy of offering good prices forthe chronometers of great excellence, and that I have given muchattention to the decision on their merits; and I am convinced thatthis system has greatly contributed to the remarkably steadyimprovement in the performance of chronometers. In the trial whichterminated in August 1869, the best chronometers (taking as usual theaverage of the first six) were superior in merit to those of anypreceding year. --With the funds placed at my disposal for the Transitof Venus 1874 I purchased three 6-inch equatoreals, and have orderedtwo: I have also ordered altazimuths (with accurate vertical circlesonly), and clocks sufficient, as I expect, to equip five stations. Formethods of observation, I rely generally on the simpleeye-observation, possibly relieved of some of its uncertainty by theuse of my colour-correcting eyepiece. But active discussion has takenplace on the feasibility of using photographic and spectroscopicmethods; and it will not be easy for some time to announce that theplan of observations is settled. --There can be no doubt, I imagine, that the first and necessary duty of the Royal Observatory is tomaintain its place well as an Observing Establishment; and that thismust be secured, at whatever sacrifice, if necessary, of otherpursuits. Still the question has not unfrequently presented itself tome, whether the duties to which I allude have not, by force ofcircumstances, become too exclusive; and whether the cause of Sciencemight not gain if, as in the Imperial Observatory of Paris forinstance, the higher branches of mathematical physics should not taketheir place by the side of Observatory routine. I have often felt thedesire practically to refresh my acquaintance with what were oncefavourite subjects: Lunar Theory and Physical Optics. But I do not atpresent clearly see how I can enter upon them with that degree offreedom of thought which is necessary for success in abstruseinvestigations. " Of private history: There was a longer visit than usual to Playford, lasting till Jan. 27th. --In April he made a short excursion (of lessthan a week) with his son Hubert to Monmouth, &c. --From June 14th toJuly 2nd he was staying at Barrow House, near Keswick, with his sonHubert: during this time he was much troubled with a painfulskin-irritation of his leg and back, which lasted in some degree for along time afterwards. --From Sept. 25th to Oct. 6th he made anexcursion with his daughter Christabel to Scarborough, Whitby, &c. , and again spent a few days at Barrow House. 1871 "In April 1870 the Assistants had applied for an increase of salary, arequest which I had urged strongly upon the Admiralty. On Jan. 27 ofthis year the Admiralty answered that, on account of Mr Childers'sillness, the consideration must be deferred to next year! TheAssistants wrote bitterly to me: and with my sanction they wrote tothe First Lord. On Jan. 31st I requested an interview with Mr Baxter(secretary of the Admiralty), and saw him on Feb. 3rd, when I obtainedhis consent to an addition of _£530_. There was still a difficultywith the Treasury, but on June 27th the liberal scale wasallowed. --Experiments made by Mr Stone shew clearly that a localelevation, like that of the Royal Observatory on the hill of GreenwichPark, has no tendency to diminish the effect of railway tremors. --Thecorrection for level error in the Transit Circle having becomeinconveniently large, a sheet of very thin paper, 1/270 inch inthickness, was placed under the eastern Y, which was raised from itsbed for the purpose. The mean annual value of the level-error appearsto be now sensibly zero. --As the siege and war operations in Parisseriously interfered with the observations of small planets made atthe Paris Observatory, observations of them were continued atGreenwich throughout each entire lunation during the investment of thecity. --The new Water-Telescope has been got into working order, andperforms most satisfactorily. Observations of gamma Draconis have beenmade with it, when the star passed between 20h and 17h, with someobservations for adjustment at a still more advanced time. As theastronomical latitude of the place of observation is not known, thebearing of these observations on the question of aberration cannot becertainly pronounced until the autumn observations shall have beenmade; but supposing the geodetic latitude to be accordant with theastronomical latitude, the result for aberration appears to besensibly the same as with ordinary telescopes. --Several years since, Iprepared a barometer, by which the barometric fluctuations wereenlarged, for the information of the public; its indications areexhibited on the wall, near to the entrance gate of the Observatory. Acard is now also exhibited, in a glass case near the public barometer, giving the highest and lowest readings of the thermometer in thepreceding twenty-four hours. --Those who have given attention to thehistory of Terrestrial Magnetism are aware that Halley's MagneticChart is very frequently cited; but I could not learn that any person, at least in modern times, had seen it. At last I discovered a copy inthe library of the British Museum, and have been allowed to takecopies by photolithography. These are appended to the Magnetical andMeteorological Volume for 1869. --The trials and certificates ofhand-telescopes for the use of the Royal Navy have lately been sofrequent that they almost become a regular part of the work of theObservatory. I may state here that by availing myself of a theory ofeyepieces which I published long since in the Cambridge Transactions, I have been able to effect a considerable improvement in thetelescopes furnished to the Admiralty. --The occurrence of the TotalEclipse of the Sun in December last has brought much labour upon theObservatory. As regards the assistants and computers, the actualobservation on a complicated plan with the Great Equatoreal (a planfor which few equatoreals are sufficiently steady, but which whenproperly carried out gives a most complete solution of the geometricalproblem) has required, in observation and in computation, a largeexpenditure of time. --My preparations for the Transit of Venus haverespect only to eye-observation of contact of limbs. With all theliabilities and defects to which it is subject, this method possessesthe inestimable advantage of placing no reliance on instrumentalscales. I hope that the error of observation may not exceed fourseconds of time, corresponding to about 0. 13" of arc. I shall be veryglad to see, in a detailed form, a plan for making the proper measuresby heliometric or photographic apparatus; and should take greatinterest in combining these with the eye-observations, if my selectedstations can be made available. But my present impression is one ofdoubt on the certainty of equality of parts in the scale employed. Anerror depending on this cause could not be diminished by anyrepetition of observations. "--After referring to the desirability ofvigorously prosecuting the Meteorological Reductions (already begun)and of discussing the Magnetic Observations, the Report concludesthus: "There is another consideration which very often presents itselfto my mind; the waste of labour in the repetition of observations atdifferent observatories. . . . . I think that this consideration ought notto be put out of sight in planning the courses of differentObservatories. "--In this year De Launay's Lunar Theory waspublished. This valuable work was of great service to Airy in thepreparation of the Numerical Lunar Theory, which he subsequentlyundertook. --In the latter part of this year Airy was elected Presidentof the Royal Society, and held the office during 1872 and 1873. Atthis time he was much pressed with work, and could ill afford to takeup additional duties, as the following quotation from a letter to oneof his friends shews: "The election to the Presidency of R. S. Isflattering, and has brought to me the friendly remembrances of manypersons; but in its material and laborious connections, I could wellhave dispensed with it, and should have done so but for the respectfulway in which it was pressed on me. " Of private history: There was the usual winter visit to Playford. --InApril he made a short trip to Cornwall with his daughter Annot. --InJune he was appointed a Companion of the Bath, and was presented atCourt on his appointment. --Mrs Airy was staying with her daughter, MrsRouth, at Hunstanton, during June, her state of health being somewhatimproved. --From August 1st to 28th he was chiefly in Cumberland, atBarrow House, and at Grange, Borrowdale, where his son Osmund wasstaying for a holiday. 1872 "From the Report to the Board of Visitors it appears that 'The NormalSiderial Clock for giving sidereal time by galvanic communication tothe Astronomical Observatory was established in the Magnetic Basementin 1871, June; that locality being adapted for it on account of theuniformity of temperature, the daily changed of temperature rarelyexceeding 1° Fahrenheit. Its escapement is one which I suggested manyyears ago in the Cambridge Transactions; a detached escapement, veryclosely analogous to the ordinary chronometer escapement, the pendulumreceiving an impulse only at alternate vibrations. . . . The steadinessof rate is very far superior to any that we have previouslyattained. '--The aspect of railway enterprise is at present favourableto the Park and to the Observatory. The South-Eastern Railway Companyhas made an arrangement with the Metropolitan Board of Works forshifting the course of the great Southern Outfall Sewer. This enablesthe Company to trace a new line for the railway, passing on the northside of London Street, at such a distance from the Observatory as toremove all cause of alarm. I understand that the Bill, which wasunopposed, has passed the Committee of the House of Commons. I trustthat the contest, which has lasted thirty-seven years, is nowterminated. --The observations of 7 Draconis with the Water-Telescope, made in the autumn of 1871, and the spring of 1872, are reduced, thelatter only in their first steps. . . . Using the values of the levelscales as determined by Mr Simms (which I have no reason to believe tobe inaccurate) the spring and autumn observations of 1871 absolutelynegative the idea of any effect being produced on the constant ofaberration by the amount of refracting medium traversed by thelight. --The great Aurora of 1872 Feb. 4 was well observed. On thisoccasion the term Borealis would have been a misnomer, for thephenomenon began in the South and was most conspicuous in theSouth. Three times in the evening it exhibited that umbrella-likeappearance which has been called (perhaps inaccurately) a corona. Ihave very carefully compared its momentary phenomena with thecorresponding movements of the magnetometers. In some of the mostcritical times, the comparison fails on account of the violentmovements and consequent faint traces of the magnetometers. I have notbeen able to connect the phases of aurora and those of magneticdisturbance very distinctly. --The Report contains a detailed accountof the heavy preparations for the observation of the Transit of Venus1874, including the portable buildings for the instruments, theinstruments themselves (being a transit-instrument, an altazimuth, andan equatoreal, for each station), and first class and second-classclocks, all sufficient for the equipment of 5 stations, and continuesthus: I was made aware of the assent of the Government to the wish ofthe Board of Visitors, as expressed at their last meeting, thatprovision should be made for the application of photography to theobservation of the Transit of Venus. It is unnecessary for me toremark that our hope of success is founded entirely on our confidencein Mr De La Rue. Under his direction, Mr Dallmeyer has advanced far inthe preparation of five photoheliographs. . . . The subject is recognizedby many astronomers as not wholly free from difficulties, but it isgenerally believed that these difficulties may be overcome, and Mr DeLa Rue is giving careful attention to the most important of them. --Itake this opportunity of reporting to the Board that the Observatorywas honoured by a visit of His Majesty the Emperor of Brazil, whominutely examined every part. "--After referring to various subjectswhich in his opinion might be usefully pursued systematically at theObservatory, the Report proceeds thus: "'The character of theObservatory would be somewhat changed by this innovation, but not, asI imagine, in a direction to which any objection can be made. It wouldbecome, pro tanto, a physical observatory; and possibly in time itsoperations might be extended still further in a physicaldirection. '--The consideration of possible changes in the future ofthe Observatory leads me to the recollection of actual changes in thepast. In my Annual Reports to the Visitors I have endeavoured tochronicle these; but still there will be many circumstances which atpresent are known only to myself, but which ought not to be beyond thereach of history. I have therefore lately employed some time indrawing up a series of skeleton annals of the Observatory (whichunavoidably partakes in some measure of the form of biography), andhave carried it through the critical period, 1836-1851. If I shouldcommand sufficient leisure to bring it down to 1861, I think that Imight then very well stop. " (The skeleton annals here referred to areundoubtedly the manuscript notes which form the basis of the presentbiography. Ed. )--"On Feb. 23rd in this year I first (privately) formedthe notion of preparing a numerical Lunar Theory by substitutingDelaunay's numbers in the proper Equations and seeing what would comeof it. " Of private history: There was the usual visit to Playford--in thisyear later than usual--from Feb. 4th to Mar. 4th. The letters writtenduring this visit are, as usual, full of freshness and delight atfinding himself in his favourite country village. --On June 5th he wentto Barrow House, near Keswick, to be present at the marriage of hissecond son Hubert to Miss S. C. Langton, daughter of Z. Langton Esq. , of Barrow House. --After the wedding he made a trip through theTrossachs district of Scotland with his daughter Annot, and returnedto Greenwich on June 17th. On the 26th June 1872 Airy was appointed a Knight Commander of theMost Honourable Order of the Bath: he was knighted by the Queen atOsborne on the 30th of July. In the course of his official career hehad three times been offered Knighthood, and had each time declinedit: but it seemed now as if his scruples on the subject were removed, and it is probable that he felt gratified by the public recognition ofhis services. Of course the occasion produced many letters ofcongratulation from his friends: to one of these he replied asfollows: "The real charm of these public compliments seems to be, thatthey excite the sympathies and elicit the kind expressions of privatefriends or of official superiors as well as subordinates. In every wayI have derived pleasure from these. " From the Assistants of the RoyalObservatory he received a hearty letter of congratulation containingthe following paragraph. "Our position has naturally given us peculiaropportunities for perceiving the high and broad purposes which havecharacterized your many and great undertakings, and of witnessing theuntiring zeal and self-denial with which they have been pursued. " * * * * * On the 18th of March 1872 Airy was nominated a Foreign Associate ofthe Institut de France, to fill the place vacant by the death of SirJohn Herschel. The following letter of acknowledgment shews how muchhe was gratified by this high scientific honour: ROYAL OBSERVATORY, GREENWICH, _1872, March 23_. _À_ Messieurs Messieurs ELIE DE BEAUMONT, _et_ J. B. DUMAS, _Secrétaires perpetuels de l'Académie des Sciences, Institut de France. _ GENTLEMEN, I am honoured with your letter of March 18, communicating to me mynomination by the Academy of Sciences to the place rendered vacant inthe class of Foreign Associates of the Academy by the decease of SirJohn Herschel, and enclosing Copy of the Decree of the President ofthe French Republic approving the Election. It is almost unnecessary for me to attempt to express to you the prideand gratification with which I receive this announcement. By universalconsent, the title of _Associé Etranger de l'Académie des Sciences_ isrecognised as the highest distinction to which any man of science canaspire; and I can scarcely imagine that, unless by the flatteringinterpretation of my friends in the Academy, I am entitled to bearit. But in any case, I am delighted to feel that the bands offriendship are drawn closer between myself and the distinguished bodywhom, partly by personal intercourse, partly by correspondence, and inevery instance by reputation, I have known so long. I beg that you will convey to the Academy my long-felt esteem for thatbody in its scientific capacity, and my deep recognition of itsfriendship to me and of the honor which it has conferred on me in thelate election. I have the honor to be Gentlemen, Your very faithful servant, G. B. AIRY. * * * * * On the 20th November 1872 Airy was nominated a Grand Cross in theImperial Order of the Rose of Brazil: the insignia of the Order wereaccompanied by an autograph letter from the Emperor of Brazil, ofwhich the following is a transcript. MONSIEUR, Vous êtes un des doyens de la science, et le Président de l'illustreSociété, qui a eu la bienveillance d'inscrire mon nom parmi ceux deses associés. La manière, dont vous m'avez fait les honneurs de votreObservatoire m'a imposé aussi l'agréable devoir d'indiquer votre nom àl'empereur de Brésil pour un témoignage de haute estime, dont je suisfort heureux de vous faire part personellement, en vous envoyant lesdécorations que vous garderez, an moins, comme un souvenir de mavisite à Greenwich. J'espère que vous m'informerez, quand il vous sera aisé, des travauxde votre observatoire, et surtout de ce que l'on aura fait pourl'observation du passage de Vénus et la détermination exacte de lapassage. J'ai reçu déjà les _Proceedings de la Royal Society_ lesquelsm'intéressent vivement. Je voudrais vous écrire dans votre langue, mais, comme je n'en ai pasl'habitude, j'ai craigné de ne pas vous exprimer tout-à-fait lessentiments de Votre affectionné, D. PEDRO D'ALCANTARA. RIO, _22 Octobre, 1872_. * * * * * Airy's reply was as follows: ROYAL OBSERVATORY, GREENWICH, _1872, November 26_. SIRE, I am honoured with your Imperial Majesty's autograph letter of October22 informing me that, on considering the attention which the RoyalSociety of London had been able to offer to your Majesty, as well asthe explanation of the various parts of the establishment of thisObservatory which I had the honor and the high gratification tocommunicate, You had been pleased to place my name in the ImperialOrder of the Rose, and to present to me the Decorations of Grand Crossof that Order. With pride I receive this proof of Your Majesty's recollection of yourvisit to the scientific institutions of Great Britain. The Diploma of the appointment to the Order of the Rose, under theImperial Sign Manual, together with the Decorations of the Order, havebeen transmitted to me by his Excellency Don Pereira de Andrada, YourMajesty's Representative at the British Court. Your Majesty has been pleased to advert to the approaching Transit ofVenus, on the preparations for which you found me engaged. It isunfortunate that the Transit of 1874 will not be visible at Rio deJaneiro. For that of 1882, Rio will be a favourable position, and wereckon on the observations to be made there. Your Majesty may beassured that I shall loyally bear in mind your desire to be informedof any remarkable enterprise of this Observatory, or of any principalstep in the preparations for the Transit of Venus and of its results. I have the honor to be Sire, Your Imperial Majesty's very faithful servant, G. B. AIRY. _To His Majesty The Emperor of Brazil. _ * * * * * Airy's old friend, Adam Sedgwick, was now very aged and infirm, buthis spirit was still vigorous, and he was warm-hearted as ever. Thefollowing letter from him (probably the last of their longcorrespondence) was written in this year, and appears characteristic: TRINITY COLLEGE, CAMBRIDGE, _May 10, 1872_. MY DEAR AIRY, I have received your card of invitation for the 1st of June, and withgreat joy should I count upon that day if I thought that I should beable to accept your invitation: but alas I have no hope of the kind, for that humiliating malady which now has fastened upon me for a fullyear and a half has not let go its hold, nor is it likely to do so. Aman who is journeying in the 88th year of his pilgrimage is not likelyto throw off such a chronic malady. Indeed were I well enough to comeI am deaf as a post and half blind, and if I were with you I shouldonly be able to play dummy. Several years have passed away since I waslast at your Visitation and I had great joy in seeing Mrs Airy andsome lady friends at the Observatory, but I could not then attend thedinner. At that Meeting were many faces that I knew, but strangelyaltered by the rude handling of old Time, and there were many newfaces which I had never seen before at a Royal Society Meeting; butworse than all, all the old faces were away. In vain I looked roundfor Wollaston, Davy, Davies Gilbert, Barrow, Troughton, &c. &c. ; andthe merry companion Admiral Smyth was also away, so that my last visithad its sorrowful side. But why should I bother you with these oldman's mopings. I send an old man's blessing and an old man's love to all the membersof your family; especially to Mrs Airy, the oldest and dearest of mylady friends. I remain, my dear Airy, Your true-hearted old friend, his ADAM X SEDGWICK. Mark P. S. Shall I ever again gaze with wonder and delight from the greatwindow of your Observatory. The body of the above letter is in the handwriting of an amanuensis, but the signature and Postscript are in Sedgwick's handwriting. (Ed. ) * * * * * 1873 "Chronographic registration having been established at the ParisObservatory, Mr Hilgard, principal officer of the American CoastSurvey, has made use of it for determining the longitude of Harvardfrom Greenwich, through Paris, Brest, and St Pierre. For this purposeMr Hilgard's Transit Instrument was planted in the Magnetic Court. Iunderstand that the result does not sensibly differ from that obtainedby Mr Gould, through Valentia and Newfoundland. --It was known to thescientific world that several of the original thermometers, constructed by Mr Sheepshanks (in the course of his preparation of theNational Standard of Length) by independent calibration of the bores, and independent determination of the freezing and boiling points onarbitrary graduations, were still preserved at the Royal Observatory. It was lately stated to me by M. Tresca, the principal officer of theInternational Metrical Commission, that, in the late unhappy war inParis, the French original thermometers were destroyed; and M. Trescarequested that, if possible, some of the original thermometers made byMr Sheepshanks might be appropriated to the use of the InternationalCommission. I have therefore transferred to M. Tresca the threethermometers A. 6, S. 1, S. 2, with the documentary information relatingto them, which was found in Mr Sheepshanks's papers; retaining sixthermometers of the same class in the Royal Observatory. --The SiderealStandard Clock continues to give great satisfaction. I am considering(with the aid of Mr Buckney, of the firm of E. Dent and Co. ) anarrangement for barometric correction, founded on the principle ofaction on the pendulum by means of a magnet which can be raised orlowered by the agency of a large barometer. --The Altazimuth hasreceived some important alterations. An examination of the results ofobservations had made me dissatisfied with the bearings of thehorizontal pivots in their Y's. Mr Simms, at my request, changed thebearings in Y's for bearing in segments of circles, a constructionwhich has worked admirably well in the pivots of the Transit Circle. "(And in various other respects the instrument appears to have receiveda thorough overhauling. Ed. )--"With the consent of the Royal Societyand of the Kew Committee, the Kew Heliograph has been planted in thenew dome looking over the South Ground. It is not yet finallyadjusted. --Some magnetic observations in the Britannia and Conwaytubular bridges were made last autumn. For this purpose I detached anAssistant (Mr Carpenter), who was aided by Capt. Tupman, R. M. A. ; inother respects the enterprise was private and at private expense. --Therates of the first six chronometers (in the annual trials) arepublished, in a form which appears most likely to lead to examinationof the causes that influence their merits or demerits. This report isextensively distributed to British and Foreign horologists andinstrument-makers. All these artists appear to entertain theconviction that the careful comparisons made at this Observatory, andthe orderly form of their publication, have contributed powerfully tothe improvement of chronometers. --Very lately, application has beenmade to me, through the Board of Trade, for plans and otherinformation regarding time-signal-balls, to assist in guiding theauthorities of the German Empire in the establishment of time signalsat various ports of that State. In other foreign countries the systemis extending, and is referred to Greenwich as its origin. --Thearrangements and preparations for the observation of the Transit ofVenus occupied much attention. With regard to the photoheliographs itis proposed to make trial of a plan proposed by M. Janssen, fornumerous photographs of Venus when very near to the Sun's limb. OnApr. 26th the engaging of photographic teachers was sanctioned. Observers were selected and engaged. A working model of theTransit was prepared, and the use of De La Rue's Scale waspractised. There was some hostile criticism of the stations selectedfor the observation of the Transit, which necessitated a formalreply. --Reference is made to the increase of facilities for makingmagnetical and meteorological observations. The inevitable result ofit is, that observations are produced in numbers so great thatcomplete reduction becomes almost impossible. The labour of reductionis very great, and it is concluded that, of the enormous number ofmeteorological observations now made at numerous observatories, veryfew can ever possess the smallest utility. --Referring to my NumericalLunar Theory: on June 30th, 1873, a theory was formed, nearly but notperfectly complete. Numerical development of powers of a÷r andr÷a. Factors of corrections to Delaunay first attempted, but entirelyin numerical form. "--In March of this year Airy was consulted by MrW. H. Barlow, C. E. , and Mr Thomas Bouch (the Engineer of the TayBridge, which was blown down in 1879, and of a proposed scheme for aForth Bridge in 1873) on the subject of the wind pressure, &c. , thatshould be allowed for in the construction of the bridge. Airy's reporton this question is dated 1873, Apr. 9th: it was subsequently muchreferred to at the Official Enquiry into the causes of the failure ofthe Tay Bridge. --At the end of this year Airy resigned the Presidencyof the Royal Society. In his Address to the Society on Dec. 1st hestated his reasons in full, as follows: "the severity of officialduties, which seem to increase, while vigour to discharge them doesnot increase; and the distance of my residence. . . . Another cause is adifficulty of hearing, which unfits me for effective action asChairman of Council. " Of private history: There was the usual visit to Playford in January:also a short visit in May: and a third visit at Christmas. --There wasa short run in June, of about a week, to Coniston, with one of hisdaughters. --And there was a trip to Weymouth, &c. , for about 10 days, with one of his daughters, in the beginning of August--On his returnfrom the last-mentioned trip, Airy found a letter from the Secretaryof the Swedish Legation, enclosing the Warrant under the Royal SignManual of His Majesty (Oscar), the King of Sweden and Norway, by whichhe was nominated as a First Class Commander of the Order of the NorthStar, and accompanying the Decorations of that Order. 1874 "In this year Mr Glaisher resigned his appointment: I placed hisDepartment (Magnetical and Meteorological) under Mr Ellis. --A balanceof peculiar construction has been made by Mr Oertling, from myinstructions, and fixed near the public barometer at the EntranceGate. This instrument enables the public to test any ordinary poundweight, shewing on a scale the number of grains by which it is tooheavy or too light. --Fresh counterpoises have been attached to theGreat Equatoreal to balance the additional weight of the newSpectroscope, which was finally received from Mr Browning's hands onMay 2nd of the present year. The Spectroscope is specifically adaptedto sweeping round the Sun's limb, with a view to mapping out theprominences, and is also available for work on Stars and Nebulae, thedispersive power being very readily varied. An induction-coil, capableof giving a six-inch spark, has been made for this instrument by MrBrowning. --Some new classes of reductions of the meteorologicalobservations from 1848 to 1868 have been undertaken and completed inthe past year. The general state of this work is as follows: Thediurnal changes of the dry-bulb thermometer, as depending on themonth, on the temperature waves, on the barometric waves, on theovercast and cloudless states of the sky, and on the direction of thewind, have been computed and examined for the whole period; and theexhibition of the results is ready for press. The similar reductionsfor the wet-bulb thermometer are rapidly approaching completion. --Regarding the preparations for the Transit of Venus Expeditions. Originally five stations were selected and fully equippedwith equatoreals, transits, altazimuths, photoheliographs, and clocks;but I have since thought it desirable to supplement these by twobranch stations in the Sandwich Islands and one in Kerguelen's Island;and the additional instruments thus required have been borrowed fromvarious sources, so that there is now an abundant supply ofinstrumental means. . . . There will thus be available for observation ofthe Transit of Venus 23 telescopes, nine of which will be providedwith double-image-micrometers; and five photoheliographs; and fordetermination of local time, and latitude and longitude, there will benine transits and six altazimuths. . . . All the observers have undergonea course of training in photography; first, under a professionalphotographer, Mr Reynolds, and subsequently under Capt. Abney, R. E. , whose new dry-plate process is to be adopted at all the BritishStations. . . . A Janssen slide, capable of taking 50 photographs ofVenus and the neighbouring part of the Sun's limb at intervals of onesecond, has been made by Mr Dallmeyer for each of the fivephotoheliographs. "--Attached to the Report to the Visitors is a copyof the Instructions to Observers engaged in the Transit of VenusExpeditions, prepared with great care and in remarkable detail. --"Inthe past spring I published in the Monthly Notices of the RoyalAstronomical Society a statement of the fundamental points in a newtreatment of the Lunar Theory, by which, availing myself of all thathas been done in the best algebraical investigations of that theory, Itrust to be able by numerical operations only to give greater accuracyto final results. Considerable progress has been made in the extensivenumerical developments, the work being done, at my private expense, entirely by a junior computer; and I hope, at any rate, to put it insuch a state that there will be no liability to its entire loss. Whenthis was reported to the Board of Visitors, it was resolved on themotion of Prof. Stokes, that this work, as a public expense, ought tobe borne by the Government; and this was forwarded to theAdmiralty. On June 24th I wrote to the Secretary of the Admiralty, asking for _£100_ for the present year, which after the usualenquiries and explanations was sanctioned on Aug. 29th. " Of private history: There were short visits to Playford in January, June, and October, but only for a few days in each case. --In Marchthere was a run of two or three days to Newnham (on the Severn) to seethe Bore on the Severn, and to Malvern. --In July he went to Newcastleto observe with Mr Newall's great telescope, but the weather wasunfavourable: he then went on to Barrow House near Keswick, and spenta few days there, with excursions among the mountains. --On Aug. 13thhe went with his daughter Christabel to the Isle of Arran, and then byGlasgow to the Trosachs, where he made several excursions to verifythe localities mentioned in the "Lady of the Lake. "--While in Scotlandhe heard of the death of his brother, the Rev. William Airy, andtravelled to Keysoe in Bedfordshire to attend the funeral; andreturned to Greenwich on Aug. 24th. 1875 "In October of this year I wrote to the Admiralty that I had groundsfor asking for an increase of my salary: because the pension which hadbeen settled on my wife, and which I had practically recognized aspart of my salary, had been terminated by her death; so that my salarynow stood lower by _£200_ than that of the Director of Studies of theRoyal Naval College. The Admiralty reply favourably, and on Nov. 27ththe Treasury raise my salary to _£1_, 200. --For the service of theClock Movement of the Great Equatoreal, a water-cistern has beenestablished in the highest part of the Ball-Turret, the necessity forwhich arose from the following circumstance: The Water Clock wassupplied by a small pipe, about 80 feet in length, connected with the3-inch Observatory main (which passes through the Park), at a distanceof about 250 feet from any other branch pipe. In spite of thisdistance I have seen that, on stopping the water-tap in theBattery-Basement under the North-East Turret, the pressure in thegauge of the Water Clock has been instantly increased by more than 40lbs. Per square inch. The consequent derangement of the Water Clock inits now incessant daily use became intolerable. Since the independentsupply was provided, its performance has been most satisfactory. --Withthe Spectroscope the solar prominences have been mapped on 28 daysonly; but the weather of the past winter was exceptionallyunfavourable for this class of observation. After mapping theprominences, as seen on the C line, the other lines, especially F andb, have been regularly examined, whenever practicable. Great care hasbeen taken in determining the position, angle, and heights of theprominences in all cases. The spectrum of Coggia's Comet was examinedat every available opportunity last July, and compared directly withthat of carbon dioxide, the bands of the two spectra being sensiblycoincident. Fifty-four measures of the displacement of lines in thespectra of 10 stars, as compared with the corresponding lines in thespectra of terrestrial elements (chiefly hydrogen), have been made, but some of these appear to be affected by a constant error dependingon faulty adjustment of the Spectroscope. --Photographs of the Sun havebeen taken with the Kew Photoheliograph on 186 days; and of these 377have been selected for preservation. The Moon, Jupiter, Saturn, andseveral stars (including the Pleiades and some double stars) have beenphotographed with the Great Equatoreal, with fairly satisfactoryresults, though further practice is required in this class of work. --Iwould mention a supplemental mechanism which I have myself introducedinto some chronometers. I have long remarked that, in ordinary goodchronometers, the freedom from irregularities depending on mechanicalcauses is most remarkable; but that, after all the efforts of the mostjudicious makers, there is in nearly every case a perceptible defectof thermal compensation. There is great difficulty in correcting theresidual fault, not only because an inconceivably small movement ofthe weights on the balance-curve is required, but also because itendangers the equilibrium of the balance. The mechanism adopted toremedy the defect is described in a Paper in the Horological Journalof July 1875 by Mr W. Ellis, and has received the approval of someable chronometer-makers. --With respect to the Transit of VenusExpeditions: The parties from Egypt and Rodriguez are returned. I amin continual expectation of the arrival of the other parties. Ibelieve the eye-observations and the ordinary photographs to be quitesuccessful; I doubt the advantage of the Janssen; one of thedouble-image-micrometers seems to have failed; and theZenith-telescope gives some trouble. At three stations at Rodriguez, and three at Kerguelen, the observations appear to have been mostsuccessful. At the Sandwich Islands, two of the stations appear tohave been perfectly successful (except that I fear that the Janssenhas failed), and a rich series of lunar observations for longitude isobtained. At New Zealand, I grieve to say, the observations weretotally lost, entirely in consequence of bad weather. There has beenlittle annoyance from the dreaded 'black drop. ' Greater inconvenienceand doubt have been caused by the unexpected luminous ring roundVenus. --With regard to the progress of my proposed New Lunar Theory:Three computers are now steadily employed on the work. It will beremembered that the detail and mass of this work are purely numerical;every numerical coefficient being accompanied with a symbolicalcorrection whose value will sometimes depend on the time, but in everycase is ultimately to be obtained in a numerical form. Of thesecoefficients, extracted (for convenience) from Delaunay's results, there are 100 for parallax, 182 for longitude, 142 for latitude; thearguments being preserved in the usual form. "--After reviewing thechanges that had taken place at the Observatory during the past fortyyears, the Report to the Board of Visitors concludes thus: "I muchdesire to see the system of time-signals extended, by clocks or dailysignals, to various parts of our great cities and our dockyards, andabove all by hourly signals on the Start Point, which I believe wouldbe the greatest of all benefits to nautical chronometry. Should anyextension of our scientific work ever be contemplated, I would remarkthat the Observatory is not the place for new physical investigations. It is well adapted for following out any which, originatingwith private investigators, have been reduced to laws susceptibleof verification by daily observation. The National Observatorywill, I trust, always remain on the site where it was firstplanted, and which early acquired the name of 'Flamsteed Hill. 'There are some inconveniences in the position, arising principallyfrom the limited extent of the hill, but they are, in my opinion, veryfar overbalanced by its advantages. "--In a letter on the subject ofthe Smith's Prizes Examination at Cambridge, which was always a matterof the greatest interest to him, Airy renewed his objections to thepreponderance in the Papers of a class of Pure Mathematics, which heconsidered was never likely under any circumstances to give theslightest assistance to Physics. And, as before, these remarks calledforth a rejoinder from Prof. Cayley, who was responsible for many ofthe questions of the class referred to. --In this year Airy completedhis "Notes on the Earlier Hebrew Scriptures, " which were shortlyafterwards published as a book by Messrs Longmans, Green, & Co. In hisletter to the publishers introducing the subject, he says, "For manyyears past I have at times put together a few sentences explanatory asI conceive of the geographical and historical circumstances connectedwith the principal events recorded in the Hebrew Scriptures. The viewwhich I take is free, but I trust not irreverent. They terminate witha brief review of Colenso's great work. The collection now amounts toa small book. " From the references already given in previous years tohis Papers and correspondence on the geography of Exodus, hiscorrespondence with Colenso, &c. &c. , it will be seen that he took agreat interest in the early history of the Israelites. --On August10th, 1875, Airy celebrated the Bicentenary of the Royal Observatoryby a dinner in the Octagon Room, which was attended by the Presidentsof the Royal Society and the R. Astr. Society, and by a large numberof Scientific gentlemen interested in Astronomy. --In February he wasrevising his Treatise on "Probabilities. " Of private history: up to Jan. 16th Airy was at Playford asusual. --For about a week in April he was in the Isle of Man with hisdaughter Christabel. --In June there was a short trip to Salisbury, Blandford, and Wimborne. --On August 12th he started with his daughterAnnot for a holiday in Cumberland, but on the next day he was recalledby a telegram with the intelligence that a change for the worse hadcome over his wife's health. Lady Airy died on August 13th, 1875. Forthe last five years of her life she had been very helpless from theeffects of a paralytic stroke--a very sad ending to a bright and happylife--and had been continually nursed throughout this time by her twounmarried daughters with the greatest self-denial and devotion. Herhusband had been unremitting in his care and attention. Nothing waswanting that the most thoughtful kindness could supply. And in all histrips and excursions his constant and kind letters shewed how anxioushe was that she should participate in all his interests andamusements. From the nature of the case it could hardly be said thather death was unexpected, and he received the shock with the manlysteadiness which belonged to him. Lady Airy was buried in Playfordchurchyard. --From Sept. 22nd to Oct. 4 he made a short expedition toWales (Capel Curig, &c. ). --On Dec. 15th he attended the Commemorationat Trinity College, Cambridge. --On Dec. 22nd he went as usual toPlayford. In this year Airy received the high honour of the Freedom of the Cityof London, in the following communication: STONE, Mayor. --A Common Council holden in the Chamber of the Guildhallof the City of London, on Thursday the 29th day of April 1875. Resolved Unanimously That the Freedom of this City in a Gold Box of the value of Onehundred guineas be presented to Sir George Biddell Airy, K. C. B. , D. C. L. , LL. D. &c. , Astronomer Royal, as a recognition of hisindefatigable labours in Astronomy, and of his eminent services in theadvancement of practical science, whereby he has so materiallybenefited the cause of Commerce and Civilization. MONCKTON. This Resolution was forwarded with a letter from Benjamin Scott, theChamberlain. Airy's reply was as follows: ROYAL OBSERVATORY, GREENWICH, S. E. _1875, May 1_. DEAR SIR, I have the honour to acknowledge your letter of April 30, accompaniedwith Copy of the Resolution of the Common Council of the City ofLondon passed at their Meeting of April 29, under signature of theTown Clerk, That the Freedom of the City of London in a valuable Boxbe presented to me, in recognition of works stated in theResolution. And I am requested by you to inform you whether it is myintention to accept the compliment proposed by the Corporation. In reply, I beg you to convey to the Right Honorable the Lord Mayorand the Corporation that I accept with the greatest pride and pleasurethe honour which they propose to offer to me. The Freedom of our GreatCity, conferred by the spontaneous act of its Municipal Governors, isin my estimation the highest honour which it is possible to receive;and its presentation at this time is peculiarly grateful to me. I have the honour to be, Sir, Your very obedient servant, G. B. AIRY. _Benjamin Scott, Esq. , &c. &c. &c. Chamberlain of the Corporation of the City of London. _ As it was technically necessary that a Freeman of the City of Londonshould belong to one or other of the City Companies, the WorshipfulCompany of Spectacle Makers through their clerk (with very greatappropriateness) enquired whether it would be agreeable that thatCompany should have the privilege of conferring their Honorary Freedomon him, and added: "In soliciting your acquiescence to the proposal Iam directed to call attention to the fact that this Guild is permittedto claim all manufacturers of Mathematical and AstronomicalInstruments within the City of London, which is now pleaded as anapology for the wish that one so distinguished as yourself in the useof such Instruments should be enrolled as a Member of this Craft. " Inhis reply, accepting the Freedom of the Company, Airy wrote thus: "Ishall much value the association with a body whose ostensible titlebears so close a relation to the official engagements which have longoccupied me. I have had extensive experience both in arranging and inusing optical and mathematical instruments, and feel that my ownpursuits are closely connected with the original employments of theCompany. " The Freedom of the Company was duly presented, and theoccasion was celebrated by a banquet at the Albion Tavern on Tuesday, July 6th. The Freedom of the City of London was conferred at a Court of CommonCouncil held at the Guildhall on Thursday the 4th of November. Inpresenting the gold box containing the Freedom, the Chamberlain, in aneloquent speech, first referred to the fact that this was the firstoccasion on which the Freedom had been conferred on a person whosename was associated with the sciences other than those of war andstatecraft. He then referred to the solid character of his work, inthat, while others had turned their attention to the more attractivefields of exploration, the discovery of new worlds or of novelcelestial phenomena, he had incessantly devoted himself to the lessinteresting, less obtrusive, but more valuable walks of practicalastronomy. And he instanced as the special grounds of the honourconferred, the compilation of nautical tables of extraordinaryaccuracy, the improvement of chronometers, the correction of thecompasses of iron ships, the restoration of the standards of lengthand weight, and the Transit of Venus Expeditions. In his reply Airystated that he regarded the honour just conferred upon him as thegreatest and proudest ever received by him. He referred to the factthat the same honour had been previously conferred on the valuedfriend of his youth, Thomas Clarkson, and said that the circumstanceof his succeeding such a man was to himself a great honour andpleasure. He alluded to his having received a small exhibition fromone of the London Companies, when he was a poor undergraduate atCambridge, and acknowledged the great assistance that it had been tohim. With regard to his occupation, he said that he had followed it ina great measure because of its practical use, and thought it fortunatethat from the first he was connected with an institution in whichutility was combined with science. The occasion of this presentationwas celebrated by a Banquet at the Mansion House on Saturday July 3rd, 1875, to Sir George Airy (Astronomer Royal) and the Representatives ofLearned Societies. There is no doubt that Airy was extremely gratified by the honour thathe had received. It was to him the crowning honour of his life, andcoming last of all it threw all his other honours into the shade. Tohis independent and liberal spirit there was something peculiarlytouching in the unsolicited approbation and act of so powerful anddisinterested a body as the Corporation of the City of London. CHAPTER IX. AT GREENWICH OBSERVATORY FROM JANUARY 1ST, 1876, TO HIS RESIGNATION OF OFFICE ON AUGUST 15TH, 1881. 1876 "At the door from the Front Court to the staircase of the Octagon Room(the original entrance to the Observatory as erected by SirChristopher Wren), a small porch-shelter has been often desired. Iproposed to fix there a fan-roof of quadrantal form, covering theupper flat stone of the external steps. --On a critical examination ofthe micrometer-screws of the Transit Circle it was found that thecorrections, which range from -1°38" to +0°76", indicate considerablewear in the screws; and it was found that as much as one-hundreth partof an inch had been worn away from some of the threads. The old screwswere consequently discarded, and new ones were made by Mr Simms. --Theadjustment of the Spectroscope has occupied a great deal ofattention. There was astigmatism of the prisms; and false lightreflected from the base of the prisms, causing loss both of light andof definition. The latter defect was corrected by altering the angles, and then astigmatism was corrected by a cylindrical lens near theslit. The definition in both planes was then found to be perfect. --Thenumber of small planets has now become so great, and the interest ofestablishing the elements of all their orbits so small, --while at thesame time the light of all those lately discovered is very faint, andthe difficulty and doubt of observation greatly increased, --that Ihave begun to think seriously of limiting future observations to asmall number of these objects. --All observations with the Spectroscopehave been completely reduced; the measures of lines in the spectra ofelements being converted into corresponding wave-lengths, and theobservations of displacement of lines in the spectra of stars beingreduced so as to exhibit the concluded motion in miles per second, after applying a correction for the earth's motion. Sixteen measuresof the F line in the spectrum of the Moon as compared with hydrogengive a displacement corresponding to a motion of less than two miles asecond, which seems to shew that the method of comparison now adoptedis free from systematic error; and this is supported by the manner inwhich motions of approach and recession are distributed among thestars examined on each night of observation. The results recentlyobtained appear to be on the whole as consistent as can be expected insuch delicate observations, and they support in a remarkable mannerthe conclusions of Dr Huggins, with regard to the motions of thosestars which he examined. --Photographs of the sun have been taken withthe photoheliograph on 182 days. On one of the photographs, which wasaccidentally exposed while the drop slit was being drawn up, thereappears to be a faint image of a cloud-like prominence close to thesun's limb, though the exposure probably only amounted to a fractionof a second. A prominence of unusual brilliancy was seen with theSpectroscope about the same time and in the same position withreference to the Sun's limb. All groups of Sun-spots and faculae havebeen numbered, and the dates of their first and last appearancesentered up to the present time. Areas of spots have been measured, andthe measures have been reduced to millionths of the Sun's visiblehemisphere. --The examination of the readings of the deep-sunkthermometers from 1846 to 1873 has exhibited some laws which had beensufficiently established before this time, and some which were lessknown. Among the former were the successive retardations of seasonsin successive descents, amounting to about four months at the depth of25 feet; and the successive diminutions of the annual range oftemperature. Among the latter is the character of the changes fromyear to year, which the great length of this series of observationsbrings well to light. It is found that from year to year the meantemperature of the surface for the year, varying by three or fourdegrees of Fahrenheit, follows in its changes the mean temperature ofthe atmosphere for the year, and that the changes of annualtemperature are propagated downwards, retarded in phase anddiminishing in amount of change, in the same manner (though probablynot following the same law) as the season changes. The inference fromthis is, that changes of temperature come entirely from the exteriorand in no discoverable degree from the interior; an inference whichmay be important in regard both to solar action and to geology. --Referring to the Transit of Venus observations: In theastronomical part of the reductions, there has been great labour anddifficulty in the determination of local sidereal times; some books ofobservations required extensive transcription; some instrumentalerrors are still uncertain; the latter determinations have perplexedus so much that we are inclined to believe that, in spite of the greatfacilities of reduction given by the transit instrument, it would bebetter to rely on the altazimuth for time-determinations. . . . In thephotographic part, I have confined my attention entirely to measuresof the distance between the centres of the Sun and Planet, atroublesome and complex operation. --Referring to the progress of theNumerical Lunar Theory: With a repetition of grant from the Treasury, I have usually maintained four junior computers on this work. Theprogress, though considerable, has not been so great as I had hoped, by reason of the excessive personal pressure upon me during the wholeyear. --I wrote a letter of congratulation to Le Verrier on thecompletion of his great work of Planetary Tables. --On May 13th theQueen was at South Kensington, and I attended to explain theastronomical instruments, and shewed Her Majesty one of the Transit ofVenus photographs. " Of private history: He returned from his Playford visit on the 18th ofJanuary. --In April there was a two-day trip to Colchester. --From June13th to July 12th he was travelling in the North of Scotland and theOrkneys with his daughters, staying for a short time with Mr Webster, M. P. , at Aberdeen, and with Mr Newall at Newcastle. --In Septemberthere was a week's run to Birkenhead and Keswick. --In November aweek's run to Playford. --From the 13th to 15th of December he was atCambridge, and on the 28th he went to Playford for the usual winterstay there. 1877 "In April of this year I was much engaged on the subject of Mr Gill'sexpedition to Ascension to observe for the determination of theparallax of Mars at the approaching opposition of that planet. --Alarge Direct-vision Spectroscope has been quite recently made by MrHilger under Mr Christie's direction on a new plan, in which eithergreat dispersion or great purity of spectrum is obtained by the use of'Half-prisms, ' according as the incident pencil falls first on theperpendicular or on the oblique face. In this Spectroscope either oneor two half prisms can be used at pleasure, according to thedispersion required, and there is facility for increasing the train tothree or four half-prisms, though the dispersion with two only isnearly double of that given by the large ten-prism Spectroscope. Thedefinition in this form of Spectroscope appears to be very fine. --Atthe end of May 1876, spectroscopic determinations of the Sun'srotation were made by observations of the relative displacement of theFraunhofer lines at the east and west limbs respectively. The resultsare in close agreement with the value of the rotation found fromobservations of Sun-spots. A similar determination has also been madein the case of Jupiter, with equally satisfactory results. --AnElectrometer on Sir William Thomson's plan, for continuousphotographic registration of atmospheric electricity has been receivedfrom Mr White of Glasgow. It was mounted in December. --The computationof the photographic records of the barometer from 1854 to 1873 has sofar advanced that we can assert positively that there is no trace oflunar tide in the atmosphere; but that there is a strongly markedsemi-diurnal solar tide, accompanied with a smaller diurnal tide. Weare at present engaged in comparing the barometric measures with thedirections of the wind. --Regarding the distribution of the printedobservations: There is no extensive wish for separate magneticobservations, but general magnetic results are in great demand, especially for mining operations, and to meet this a map of magneticdeclination is furnished in the newspaper called the 'CollieryGuardian. '--As regards the operations for the Transit of Venus: Thecomputing staff has by degrees been reduced to two junior computerswithin the Observatory; and one or two computers external to theObservatory, who are employed on large groups of systematiccalculations. The principal part of the calculations remaining at thedate of the last Report was that applying to the determination of thegeographical longitudes of fundamental stations. At the moment of mywriting, the last of these (the longitude of Observatory Bay, Kerguelen) is not absolutely finished:. . . The method of determiningthe geographical longitude of the principal station in each group byvertical transits of the Moon has been found very successful atHonolulu and Rodriguez. For stations in high south latitude, horizontal transits are preferable. --As regards the Numerical LunarTheory: With the view of preserving, against the ordinary chances ofdestruction or abandonment, a work which is already one ofconsiderable magnitude, I have prepared and have printed as Appendixto the Greenwich Observations (with additional copies as for aseparate work) the ordinary Equations of Lunar Disturbance, the noveltheory of Symbolical Variations, and the Numerical Developments of thequantities on the first side of the Equations. --At various times fromFebruary to May I was engaged on the reduction of Malta Tides, and ona Paper concerning the same. --In July I was awarded the Albert Medalfor my Compass corrections, and received the same from the Prince ofWales. --In February, Campbell's instrument for the registration ofsunshine was introduced: it was mounted in July. " Of private history: "I was at Playford until Jan. 19th, in closecorrespondence as usual with Mr Christie at the Observatory, andattending to my Numerical Lunar Theory. --From Mar. 29th to Apr. 2nd Iwent on a short trip to Hereford, Worcester, &c. --From June 8th to20th I was at Playford. --From Aug. 13th to Sept. 8th Airy was on anexpedition in Ireland, chiefly in the North and West, with hisdaughters. When at Dublin he visited Grubb's instrument factory. Onthe return journey he stayed for some time in the Lake District ofCumberland, and took soundings in the neighbourhood of the place ofthe 'floating island' in Derwentwater. " Airy took the greatest interest in antiquarian matters, whethermilitary or ecclesiastical, and his feelings on such matters is wellillustrated by the following letter: ROYAL OBSERVATORY, GREENWICH, S. E. _1877, February 27_. DEAR SIR, I venture to ask if you can assist me in the following matter. In the Parish Church of Playford, near Ipswich, Suffolk, was asplendid brass tombstone to Sir Thomas Felbrigg. By an act of follyand barbarism, almost unequalled in the history of the world, theIncumbent and Curate nearly destroyed the brass inscriptionsurrounding the image of the Knight. This tombstone is figured in Gough's Sepulchral Antiquities, which, Ipresume, is to be found in the British Museum. And I take the liberty to ask if you would kindly look at theengraving, and give me any suggestion as to the way in which somecopies of it could be made, in a fairly durable form. I am connectedwith the parish of Playford, and am anxious to preserve for it thismemorial of a family of high rank formerly resident there. I am, dear Sir, Very faithfully yours, G. B. AIRY. _T. Winter Jones, Esq. _ To this request Mr Winter Jones immediately acceded, and the engravingwas duly photographed, and copies were circulated with a historicalnotice of Sir George (not Sir Thomas) Felbrigg and a history of theMonument. Sir George Felbrigg was Esquire-at-Arms to Edward III. , andLord of the Manor of Playford: he died in 1400, and was buried in theNorth wall of Playford Church. 1878 The Report to the Board of Visitors has this paragraph: "I continue toremark the approaching necessity for Library extension. Without havingabsolutely decided on a site, I may suggest that I should wish toerect a brick building, about 50 feet by 20, consisting of two verylow stories (or rather of one story with a gallery running round itswalls), so low that books can be moved by hand without necessity for aladder. --In the month of December, 1877, the azimuthal error of theTransit Circle had increased to 10". A skilful workman, instructed byMr Simms, easily reduced the error to about 2". 5 (which would leaveits mean error nearly 0), the western Y being moved to the north sofar as to reduce the reading of the transit micrometer, when pointedto the south, from 35r. 500 to 35r. 000. The level error was notsensibly affected. --The Sidereal Standard Clock preserves a rateapproaching to perfection, so long as it is left without disturbanceof the galvanic-contact springs (touched by its pendulum), whichtransmit signals at every second of time to sympathetic clocks and thechronograph. A readjustment of these springs usually disturbs therate. --To facilitate the observations of stars, a new workingcatalogue has been prepared, in which are included all stars down tothe third magnitude, stars down to the fifth magnitude which have notbeen observed in the last two catalogues, and a list of 258 stars ofabout the sixth magnitude of which the places are required for theUnited States Coast Survey. The whole number of stars in our newworking list is about 2500. It may be here mentioned that an extensiveseries of observations was made, during the autumn, of about 70 stars, at the request of Mr Gill, for comparison with Mars, Ariadne, andMelpomene. --On Apr. 10th last, a very heavy fall of rain tookplace. Between Apr. 10d. 5h. And Apr. 11d. 2h. , 2. 824 inch. Wasrecorded, and 75 per cent. Of this, or 2. 12 inch. , fell in the eighthours between 13-1/2h. And 21-1/2h. ; and on May 7, 1 inch of rain fellin 50 minutes, of which 1/2 inch fell in 15 minutes. --Thesupplementary compensation continues to be applied with success toGovernment chronometers which offer facilities for its introduction, and a marked improvement in the performance of chronometers returnedafter repair by the makers appears to have resulted from the increasedattention now given to the compensation. Of the 29 competitivechronometers, 25 have the supplementary compensation. "--With regard tothe reduction of the observations of the Transit of Venus: Afterreference to the difficulties arising from the errors and theinterpretation of the language used by some of the observers, theReport continues thus: "Finally a Report was made to the Government onJuly 5th, giving as the mean result for Mean Solar Parallax 8". 76; theresults from ingress and from egress, however, differing to the extentof 0". 11. . . . After further examination and consideration, the resultfor parallax has been increased to 8". 82 or 8". 83. The results fromphotography have disappointed me much. The failure has arisen, perhapssometimes from irregularity of limb, or from atmospheric distortion, but more frequently from faintness and from want of cleardefinition. Many photographs, which to the eye appeared good, lost allstrength and sharpness when placed under the measuring microscope. Afinal result 8". 17 was obtained from Mr Burton's measures, and 8". 08from Capt. Tupman's. --With regard to the Numerical Lunar Theory: Acursory collection of the terms relating to the Areas (in theEcliptic) led me to suppose that there might be some error in thecomputations of the Annual Equation and related terms. A most jealousre-examination has however detected nothing, and has confirmed mybelief in the general accuracy of the numerical computations. I darenot yet venture to assume an error in Delaunay's theory; but Iremember that the Annual Equation gave great trouble to the late SirJohn Lubbock, and that he more than once changed his conclusions as toits true value. --In February I was engaged on the drawings andpreparations for my intended Lecture at Cockermouth on the probablecondition of the interior of the Earth. The Lecture was delivered inApril. --At different times in the autumn I was engaged on diagrams toillustrate the passage of rays through eye-pieces and double-imagemicrometers. --The miscellaneous scientific correspondence, which wasalways going on, was in this year unusually varied and heavy. " Of private history: He was at Playford till Jan. 26th. --In April hewent to Cockermouth to deliver his Lecture above-mentioned: thejourney was by Birmingham, where he stayed for two days (probably withhis son Osmund, who resided there), to Tarn Bank (the residence ofIsaac Fletcher, M. P. ): the lecture was delivered on the 22nd: he madeexcursions to Thirlmere and Barrow, and to Edward I. 's Monument, andreturned to Greenwich on the 27th. --From June 17th to 28th he was atPlayford. --From Aug. 19th to Sept. 17th he was travelling in Scotland, visiting the Tay Bridge, the Loch Katrine Waterworks, &c. , and spentthe last fortnight of his trip at Portinscale, near Keswick. OnDec. 23rd he went to Playford. 1879 "The manuscripts of every kind, which are accumulated in the ordinarytransactions of the Observatory, are preserved with the same care andarranged on the same system as heretofore. The total number of boundvolumes exceeds 4000. Besides these there is the great mass of Transitof Venus reductions and manuscripts, which when bound may be expectedto form about 200 volumes. --With regard to the numerous group of MinorPlanets, the Berlin authorities have most kindly given attention to myrepresentation, and we have now a most admirable and comprehensiveEphemeris. But the extreme faintness of the majority of these bodiesplaces them practically beyond the reach of our meridian instrument, and the difficulty of observation is in many cases further increasedby the large errors of the predicted places. --After a fine autumn, theweather in the past winter and spring has been remarkably bad. Morethan an entire lunation was lost with the Transit Circle, noobservation of the Moon on the meridian having been possible betweenJanuary 8 and March 1, a period of more than seven weeks. Neither Sunnor stars were visible for eleven days, during which period theclock-times were carried on entirely by the preceding rate of theclock. The accumulated error at the end of this time did not exceed0s'3. --Some difficulty was at first experienced with the ThomsonElectrometer, which was traced to want of insulation. This has beenmastered by the use of glass supporters, which carry some sulphuricacid. The instrument is now in excellent order, and the photographicregisters have been perfectly satisfactory since 1879, February, whenthe new insulators were applied. --From the annual curves of diurnalinequality, deduced from the Magnetic Reductions, most importantinferences may be drawn, as to the connection between magneticphenomena and sun-spots. These annual curves shew a well-markedchange in close correspondence with the number of sun-spots. About theepoch of maximum of sun-spots they are large and nearly circular, having the same character as the curves for the summer months; whilstabout the time of sun-spot minimum they are small andlemniscate-shaped, with a striking resemblance to the curves for thewinter months. The connection between changes of terrestrial magnetismand sun-spots is shewn in a still more striking manner by a comparisonwhich Mr Ellis has made between the monthly means of the diurnal rangeof declination and horizontal force, and Dr R. Wolf's 'relativenumbers' for frequency of sun-spots. --The records of sunshine withCampbell's Registering Sun-dial are preserved in a form easilyaccessible for reference, and the results are communicated weekly tothe Agricultural Gazette. --Prof. Oppolzer's results for thedetermination of the longitudes of Vienna and Berlin, made in 1877, have now been made public. They shew a remarkable agreement of theChronometric determination formerly made with the Telegraphic. It maybe of interest to recall the fact that a similar agreement was foundbetween the Chronometric and Telegraphic determinations of thelongitude of Valentia. --For observing the Transit of Venus of 1882, the general impression appears to be that it will be best to confineour observations to simple telescopic observations or micrometerobservations at Ingress and Egress, if possible at places whoselongitudes are known. For the first phenomenon (accelerated ingress)the choice of stations is not good; but for the other phenomena(retarded ingress, accelerated egress, retarded egress) there appearsto be no difficulty. --With regard to the Numerical Lunar Theory:Respecting the discordance of Annual Equation, I suspend myjudgment. I have now discussed the theory completely; and in goinginto details of secular changes, I am at this time engaged on thatwhich is the foundation of all, namely, the change of excentricity ofthe Solar Orbit, and its result in producing Lunar Acceleration. Animportant error in the theoretical formulae for Variations of RadiusVector, Longitude, and Latitude, was discovered; some calculationsdepending on them are cancelled. "--Referring to the magnitude of theprinted volume of "Greenwich Observations, " and the practicability ofreducing the extent of it, the Report states thus: "The tendency ofexternal scientific movement is to give great attention to thephenomena of the Solar disc (in which this Observatory oughtundoubtedly to bear its part). And I personally am most unwilling torecede from the existing course of magnetical and meteorologicalobservations. . . . The general tendency of these considerations is toincrease the annual expenses of the Observatory. And so it has been, almost continuously, for the last 42 years. The annual ordinaryexpenses are now between 2-1/2 and 3 times as great as in my firstyears at the Royal Observatory. --Mr Gill was appointed to the CapeObservatory, and I wrote out instructions for him in March: there wassubsequently much correspondence respecting the equipment and repairsof the Cape Observatory. "--In the Monthly Notices of the RoyalAstronomical Society for January an article had appeared headed "Noteson the late Admiral Smyth's Cycle of Celestial Objects, Vol. II. " byMr Herbert Sadler. In this article Mr Sadler had criticized the workof Admiral Smyth in a manner which Airy regarded as imputing bad faithto Admiral Smyth. He at once took up the defence of his old friendvery warmly, and proposed certain Drafts of Resolutions to the Councilof the Society. These Resolutions were moved, but were amended ornegatived, and Airy immediately resigned his office ofVice-President. There was considerable negociation on the subject, anddiscussion with Lord Lindsay, and on May 9th Airy's Resolutions wereaccepted by the Council. --In October Airy inspected the "Faraday"telegraph ship, then lying in the river near Messrs Siemens' works, and broke his finger by a fall on board the vessel. --In this year Airywrote and circulated a letter to the Members of the Senate of theUniversity of Cambridge, on the subject of the Papers set in theSmith's Prizes Examination. In this letter, as on former occasions, heobjected much to the large number of questions in "purely idlealgebra, arbitrary combinations of symbols, applicable to no furtherpurpose. " And in particular he singled out for comment the followingquestion, which was one of those set, "Using the term circle asextending to the case where the radius is a pure imaginary, it isrequired to construct the common chord of two given circles. " Thisdrew forth as usual a rejoinder from Prof. Cayley, who wroteenclosing a solution of his problem, but not at all to Airy'ssatisfaction, who replied as follows: "I am not so deeply plunged inthe mists of impossibles as to appreciate fully your explanation inthis instance, or to think that it is a good criterion for Universitycandidates. " Of private history: On Jan. 21st he returned from Playford. --On March22nd he attended the funeral of his sister at Little Welnetham nearBury St Edmunds: Miss Elizabeth Airy had lived with him at theObservatory from shortly after his appointment. --For about a week atthe end of April he was visiting Matlock, Edensor, and Buxton. --FromJune 14th to July 18th he was staying at Portinscale near Keswick. --Hewas at Playford for two or three days in October, and went there againon Dec. 23rd for his usual winter holiday. The following letter, relating to the life of Thomas Clarkson, waswritten to Dr Merivale, Dean of Ely, after reading the account in the"Times" of October 10th of the unveiling of a statue of Clarkson nearWare: ROYAL OBSERVATORY, GREENWICH, LONDON, S. E. _1879, October 11_. DEAR SIR, Pardon my intrusion on you, in reference to a transaction which hasgreatly interested me--the honour paid by you to the memory of ThomasClarkson. With very great pleasure I have heard of this step: and Ihave also been much satisfied with the remarks on it in the "Times. " Iwell remember, in Clarkson's "History of the Abolition, " which I readsome 60 years ago, the account of the circumstance, now commemoratedby you, which determined the action of his whole subsequent life. It is not improbable that, among those who still remember Clarkson, myacquaintance with him began at the earliest time of all. I knew him, intimately, from the beginning of 1815 to his death. The family whichhe represented must have occupied a very good position in society. Ihave heard that he sold two good estates to defray the expenses whichhe incurred in his personal labours for Abolition: and his brother wasGovernor of Sierra Leone (I know not at what time appointed). ThomasClarkson was at St John's College; and, as I gather from circumstanceswhich I have heard him mention, must have been a rather gay man. Hekept a horse, and at one time kept two. He took Orders in the Church;and on one occasion, in the course of his Abolition struggle, hepreached in a church. But he afterwards resolutely laid aside allpretensions to the title of Minister of the Church, and never wouldaccept any title except as layman. He was, however, a very earnestreader of theology during my acquaintance with him, and appeared to bewell acquainted with the Early Fathers. The precise words in which was announced the subject for Prize Essayin the University were "Anne liceat invitos in servitutem trahere. " After the first great victory on the slave trade question, heestablished himself in a house on the bank of Ullswater. I have notidentified the place: from a view which he once shewed me I supposedit to be near the bottom of the lake: but from an account of the stormof wind which he encountered when walking with a lady over a pass, itseemed to be in or near Patterdale. When the remains of a mountaineer, who perished in Helvellyn (as described in Scott's well-known poem), were discovered by a shepherd, it was to Mr Clarkson that theintelligence was first brought. He then lived at Bury St Edmunds. Mrs Clarkson was a lady of Bury. ButI cannot assign conjecturally any dates to his removals or hismarriage. His only son took his B. A. Degree, I think, about 1817. I think it was in 1814 that he began his occupation of PlayfordHall--a moated mansion near Ipswich, formerly of great importance--where he lived as Gentleman Farmer, managing a farm leasedfrom the Marquis of Bristol, and occupying a good position among thegentry of the county. A relative of mine, with whom I was mostintimately acquainted, lived in the same parish (where in defiance ofschool rules I spent nearly half my time, to my great advantage as Ibelieve, and where I still retain a cottage for occasional residence), and I enjoyed much of Mr Clarkson's notice. It was by his strongadvice that I was sent to Cambridge, and that Trinity College wasselected: he rode with me to Rev. Mr Rogers of Sproughton forintroductory examination; he introduced me to Rev. C. Musgrave(subsequently of Halifax), accidentally doing duty at Grundisburgh, who then introduced me to Sedgwick, Peacock, and T. Musgrave(subsequently of York). In 1825, when I spent the summer at Keswick, he introduced me to Southey and Wordsworth. Mr Clarkson lived about thirty years at Playford Hall, and died there, and lies interred with his wife, son, and grandson, in Playfordchurchyard. I joined several friends in erecting a granite obelisk tohis memory in the same churchyard. His family is extinct: but adaughter of his brother is living, first married to T. Clarkson's son, and now Mrs Dickinson, of the Rectory, Wolferton. I am, my dear Sir, Very faithfully yours, G. B. AIRY. _The Very Reverend, The Dean of Ely. _ 1880 "The Admiralty, on final consideration of the estimates, decided notto proceed with the erection of a new Library near the MagneticObservatory in the present year. In the mean time the space has beencleared for the erection of a building 50 by 20 feet. --I have removedthe Electrometer Mast (a source of some expense and some danger), theperfect success of Sir William Thomson's Electrometer rendering allfurther apparatus for the same purpose unnecessary. --Many years ago adouble-image micrometer, in which the images were formed by the doublerefraction of a sphere of quartz, was prepared by Mr Dollond forCapt. Smyth, R. N. Adopting the same principle on a larger scale, Ihave had constructed by Mr Hilger a micrometer with double refractionof a sphere of Iceland spar. Marks have been prepared for examinationof the scale, but I have not yet had opportunity of trying it. --Thespectroscopic determination of Star-motions has been steadilypursued. The stars are taken from a working list of 150 stars, whichmay eventually be extended to include all stars down to the fourthmagnitude, and it is expected that in the course of time the motionsof about 300 stars may be spectroscopically determined. --A newpressure-plate with springs has been applied by Mr Browning to Osler'sAnemometer, and it is proposed to make such modification as will givea scale extending to 50 lbs. Pressure on the square foot. Other partsof the instrument have also been renewed. --As regards the reduction ofthe magnetical results since 1863: In the study of the forms of theindividual curves; their relations to the hour, the month, the year;their connection with solar or meteorological facts; the conjecturalphysico-mechanical causes by which they are produced; there is much tooccupy the mind. I regret that, though in contemplation of thesecurves I have remarked some singular (but imperfect) laws, I have notbeen able to pursue them. --The mean temperature of the year 1879 was46. 1°, being 3. 3° below the average of the preceding 38 years. Thehighest temperature was 80. 6° on July 30, and the lowest 13. 7° onDec. 7. The mean temperature was below the average in every month ofthe year; the months of greatest deviation being January and December, respectively 6. 8° and 7. 6° below the average; the months of April, May, July, and November were each between 4° and 5° below the average. The number of hours of bright sunshine, recorded with Campbell'sSunshine Instrument, during 1879, was only 983. --In the summer of 1879Commander Green, U. S. N. , came over to this country for the purpose ofdetermining telegraphically the longitude of Lisbon, as part of achain of longitudes extending from South America to Greenwich. Asuccessful interchange of signals was made with Commander Greenbetween Greenwich and Porthcurno on four nights, 1879, June 25 to29. The results communicated by Commander Green shew that thelongitude of Lisbon Observatory, as adopted in the Nautical Almanac, requires the large correction of +8. 54". --With regard to the comingTransit of Venus in 1882: From the facility with which therequirements for geographical position are satisfied, and from therapid and accurate communication of time now given by electrictelegraph, the observation of this Transit will be comparatively easyand inexpensive. I have attached greater importance than I didformerly to the elevation of the Sun. . . . I remark that it is highlydesirable that steps be taken now for determining by telegraph thelongitude of some point of Australia. I have stated as the generalopinion that it will be useless to repeat photographic observations. --In April Mr Barlow called, in reference to the Enquiry onthe Tay Bridge Disaster. (The Bridge had been blown down onDec. 28th, 1879. ) I prepared a memorandum on the subject for the TayBridge Commission, and gave evidence in a Committee Room of the Houseof Lords on Apr. 29th. " (Much of the Astronomer Royal's evidence onthis occasion had reference to the opinions which he had expressedconcerning the wind-pressure which might be expected on the projectedForth Bridge, in 1873. )--In May Airy was consulted by thePostmaster-General in the matter of a dispute which had arisen betweenthe Post Office and the Telephone Companies, which latter were allegedto have infringed the monopoly of the Post Office in commercialtelegraphs: Airy made a declaration on the subject. --In July MrBakhuyzen came to England to determine the longitude of Leyden, onwhich he was engaged till Sept. 9th, and carried on his observationsat the Observatory. --In July Airy was much engaged in perusing therecords of Mr Gill's work at the Cape of Good Hope. Of private history: On Jan. 24th he returned from Playford. --From June14th to July 4th he was again at Playford. --From September 21st toOctober 20th he was staying at Portinscale near Keswick. --On Dec. 23rdhe went again to Playford for his winter holiday. Respecting the agitation at Cambridge for granting University degreesto women, the following extract from a letter addressed to a younglady who had forwarded a Memorial on the subject for hisconsideration, and dated Nov. 10th, 1880, contains Airy's views onthis matter. "I have not signed the Memorial which you sent for my consideration:and I will endeavour to tell you why. I entirely approve of educationof young women to a higher pitch than they do commonly reach. I thinkthat they can successfully advance so far as to be able clearly tounderstand--with gratification to themselves and with advantage tothose whose education they will superintend--much of the results ofthe highest class of science which have been obtained by men whoselives are in great measure devoted to it. But I do not think thattheir nature or their employments will permit of their mastering the_severe_ steps of beginning (and indeed all through) and the_complicated_ steps at the end. And I think it well that this theirsuccess should be well known--as it is sure to be--among theirrelatives, their friends, their visitors, and all in whom they arelikely to take interest. Their connection with such a place as GirtonCollege is I think sufficient to lead to this. But I desire above allthat all this be done in entire subservience to what I regard as_infinitely_ more valuable than any amount of knowledge, namely thedelicacy of woman's character. And here, I think, our views totallyseparate. I do not imagine that the University Degree would reallyimply, as regards education, anything more than is known to allpersons (socially concerned in the happiness of the young woman) fromthe less public testimonial of the able men who have the means ofknowing their merits. And thus it appears to me that the admission toUniversity Degree would simply mean a more extended publication oftheir names. I dread this. " 1881 "The new line of underground telegraph wires has been completed by theofficers of the General Post Office. The new route is down Croom'sHill in Greenwich, and the result of this change, at least as regardsthe earth-current wires, and probably as regards the other wires, hasnot been satisfactory. It was soon found that the indications of theearth-current wires were disturbed by a continual series of pettyfluctuations which almost completely masked the proper features ofearth currents. . . . If this fault cannot be removed, I should proposeto return to our original system of independent wires (formerly toCroydon and Dartford). --The new Azimuth-mark (for the Altazimuth), upon the parapet of the Naval College, is found to be perfectlysatisfactory as regards both steadiness and visibility. Theobservations of a low star for zero of azimuth have been omitted sincethe beginning of 1881; the mark, in combination with a high star, appearing to give all that is necessary for this purpose. --All theinstruments have suffered from the congealing of the oil during thesevere weather of the past winter, and very thorough cleaning of allthe moving parts has been necessary. --The Solar Eclipse of 1880, Dec. 31, was well observed. The first contact was observed by fourobservers and the last contact by two. The computations for theobservations have been exceptionally heavy, from the circumstance thatthe Sun was very low (86° 14' Z. D. At the last observation) and thatit has therefore been necessary to compute the refraction with greataccuracy, involving the calculation of the zenith distance for everyobservation. And besides this, eighty-six separate computations of thetabular R. A. And N. P. D. Of cusps have been required. --Amongst otherinteresting spectroscopic observations of the Sun, a remarkablespectrum of a sun-spot shewing 17 strong black lines or bands, each asbroad as b_1, in the solar spectrum, was observed on 1880, Nov. 27 and29. These bands to which there is nothing corresponding in the SolarSpectrum (except some very faint lines) have also been subsequentlyremarked in the spectrum of several spots. --The Police Ship 'Royalist'(which was injured by a collision in 1879 and had been laid up indock) has not been again moored in the river, and the series ofobservations of the temperature of the Thames is thus terminated. --Part of the month of January 1881 was, as regards cold, especially severe. The mean temperature of the period January 12 to26 (15 days) was only 24. 2°, or 14. 7° below the average; thetemperature fell below 20° on 10 days, and rose above the freezingpoint only on 3 days. The highest temperature in this period was35. 3°, the lowest 12. 7°. On January 17th (while staying at Playford)my son Hubert and I noticed an almost imperceptible movement in theupper clouds from the South-East. On that night began the terribleeasterly gale, accompanied with much snow, which lasted to the nightof the 18th. The limiting pressure of 50 lbs. On the square foot ofOsler's Anemometer was twice exceeded during this storm. --With respectto the Diurnal Inequalities of Magnetic Horizontal Force: Assuming itto be certain that they originate from the Sun's power, notimmediately, but mediately through his action on the Earth, it appearsto me (as I suggested long ago) that they are the effects of theattraction of the red end or north end of the needle by the heatedportions of our globe, especially by the heated sea, whose effectappears to predominate greatly over that of the land. I do not saythat everything is thus made perfectly clear, but I think that theleading phenomena may be thus explained. And this is almostnecessarily the way of beginning a science. --In the first few yearsafter the strict and systematic examination of competitivechronometers, beginning with 1856, the accuracy of chronometers wasgreatly increased. For many years past it has been nearlystationary. I interpret this as shewing that the effects of badworkmanship are almost eliminated, and that future improvement must besought in change of some points of construction. --Referring to theTransit of Venus in 1874, the printing of all sections of theObservations, with specimens of the printed forms employed, andremarks on the photographic operations, is very nearly completed. AnIntroduction is begun in manuscript. I am in correspondence with theCommission which is entrusted with the arrangements for observation ofthe Transit of 1882. --The Numerical Lunar Theory has been muchinterrupted by the pressure of the Transit of Venus work and otherbusiness. "--In his Report to the Board of Visitors (his 46th andlast), Airy remarks that it would be a fitting opportunity for theexpression of his views on the general objects of the Observatory, andon the duties which they impose on all who are actively concerned inits conduct. And this he proceeds to do in very considerabledetail. --On May 5th he wrote to Lord Northbrook (First Lord of theAdmiralty) and to Mr Gladstone to resign his post of AstronomerRoyal. From time to time he was engaged on the subject of a house forhis future residence, and finally took a lease of the White House atthe top of Croom's Hill, just outside one of the gates of GreenwichPark. On the 15th of August he formally resigned his office to MrW. H. M. Christie, who had been appointed to succeed him as AstronomerRoyal, and removed to the White House on the next day, August 16th. His holiday movements in the portion of the year up to August 16thconsisted in his winter visit to Playford, from which he returned onJan. 24th: and a subsequent visit to Playford from June 7th to 18th. * * * * * The following correspondence relating to Airy's retirement from officetestifies in a remarkable manner to the estimation in which hisservices were held, and to the good feeling which subsisted betweenhim and his official superiors. 10, DOWNING STREET, WHITEHALL, _June 6, 1881_. DEAR SIR GEORGE AIRY, I cannot receive the announcement of your resignation, which you havejust conveyed to me, without expressing my strong sense of thedistinction you have conferred upon the office of Astronomer Royal, and of the difficulty of supplying your place with a person of equaleminence. Let me add the expression of my best wishes for the fullenjoyment of your retirement from responsibility. I remain, dear Sir George Airy, Faithfully yours, W. E. GLADSTONE. * * * * * ADMIRALTY, _June 10th, 1881_. SIR, I am commanded by my Lords Commissioners of the Admiralty toacknowledge the receipt of your letter of the 4th instant, intimatingyour desire to retire on the 15th August next from the office ofAstronomer Royal. 2. In reply I am to acquaint you that your wishes in this matter havebeen communicated to the Prime Minister, and that the furthernecessary official intimation will in due course be made to theTreasury. 3. At the same time I am instructed by their Lordships to convey toyou the expression of their high appreciation of the remarkably ableand gifted manner, combined with unwearied diligence and devotion tothe Public Service (especially as regards the Department of the Stateover which they preside), in which you have performed the duties ofAstronomer Royal throughout the long period of forty-five years. 4. I am further to add that their Lordships cannot allow the presentopportunity to pass without giving expression to their sense of theloss which the Public Service must sustain by your retirement, and tothe hope that you may long enjoy the rest to which you are so justlyentitled. I am, Sir, Your obedient Servant, ROBERT HALL. _Sir G. B. Airy, K. C. B. &c. , &c. , Royal Observatory, Greenwich. _ * * * * * ADMIRALTY, _28th June, 1881_. SIR, My Lords Commissioners of the Admiralty have much pleasure intransmitting copy of a resolution passed by the Board of Visitors ofthe Royal Observatory on the 4th June last, bearing testimony to thevaluable services you have rendered to Astronomy, to Navigation, andthe allied Sciences throughout the long period during which you havepresided over the Royal Observatory. I am, Sir, Your obedient Servant, ROBERT HALL. _Sir George Biddell Airy, K. C. B. &c. , &c. , &c. , Royal Observatory, Greenwich. _ "The Astronomer Royal (Sir George B. Airy) having announced hisintention of shortly retiring from his position at the RoyalObservatory, the following resolution proposed by ProfessorJ. C. Adams, and seconded by Professor G. G. Stokes, was thenunanimously adopted and ordered to be recorded in the Minutes of theProceedings. "The Board having heard from the Astronomer Royal that he proposes toterminate his connection with the Observatory on the 15th of Augustnext, desire to record in the most emphatic manner their sense of theeminent services which he has rendered to Astronomy, to Navigation andthe allied Sciences, throughout the long period of 45 years duringwhich he has presided over the Royal Observatory. "They consider that during that time he has not only maintained buthas greatly extended the ancient reputation of the Institution, andthey believe that the Astronomical and other work which has beencarried on in it under his direction will form an enduring monument ofhis Scientific insight and his powers of organization. "Among his many services to Science, the following are a few whichthey desire especially to commemorate: _(a)_ "The complete re-organization of the Equipment of theObservatory. _(b)_ "The designing of instruments of exceptional stability anddelicacy suitable for the increased accuracy of observation demandedby the advance of Astronomy. _(c)_ "The extension of the means of making observations of the Moonin such portions of her orbit as are not accessible to the TransitCircle. _(d)_ "The investigation of the effect of the iron of ships uponcompasses and the correction of the errors thence arising. _(e)_ "The Establishment at the Observatory and elsewhere of a Systemof Time Signals since extensively developed by the Government. "The Board feel it their duty to add that Sir George Airy has at alltimes devoted himself in the most unsparing manner to the business ofthe Observatory, and has watched over its interests with an assiduityinspired by the strongest personal attachment to the Institution. Hehas availed himself zealously of every scientific discovery andinvention which was in his judgment capable of adaptation to the workof the Observatory; and the long series of his annual reports to theBoard of Visitors furnish abundant evidence, if such were needed, ofthe soundness of his judgment in the appreciation of suggestedchanges, and of his readiness to introduce improvements when theproper time arrived. While maintaining the most remarkable punctualityin the reduction and publication of the observations made under hisown superintendance, he had reduced, collected, and thus renderedavailable for use by astronomers, the Lunar and Planetary Observationsof his predecessors. Nor can it be forgotten that, notwithstanding hisabsorbing occupations, his advice and assistance have always been atthe disposal of Astronomers for any work of importance. "To refer in detail to his labours in departments of Science notdirectly connected with the Royal Observatory may seem to lie beyondthe province of the Board. But it cannot be improper to state that itsmembers are not unacquainted with the high estimation in which hiscontributions to the Theory of Tides, to the undulatory theory ofLight, and to various abstract branches of Mathematics are held by menof Science throughout the world. "In conclusion the Board would express their earnest hope, that in hisretirement Sir George Airy may enjoy health and strength and thatleisure for which he has often expressed a desire to enable him notonly to complete the numerical Lunar Theory on which he has beenengaged for some years past, but also to advance Astronomical Sciencein other directions. " * * * * * ADMIRALTY, _27th October, 1881_. SIR, I am commanded by my Lords Commissioners of the Admiralty to transmitto you, herewith, a copy of a Treasury Minute, awarding you a SpecialPension of _£1100_ a year, in consideration of your long and brilliantservices as Astronomer Royal. I am, Sir, Your obedient Servant, ROBERT HALL. _Sir G. B. Airy, K. C. B. , F. R. S. , &c. , &c. The White House, Croom's Hill, Greenwich. _ Copy of Treasury Minute, dated 10th October, 1881: My Lords have before them a statement of the services of Sir GeorgeBiddell Airy, K. C. B. , F. R. S. , who has resigned the appointment ofAstronomer Royal on the ground of age. Sir George Airy has held his office since the year 1835, and has also, during that period, undertaken various laborious works, demandingscientific qualifications of the highest order, and not always such ascould strictly be said to be included among the duties of his office. The salary of Sir G. Airy as Astronomer Royal is _£1200_ a year, inaddition to which he enjoys an official residence rent free, and, under ordinary circumstances he would be entitled to a pension equalto two-thirds of his salary and emoluments. My Lords, however, in order to mark their strong sense of thedistinction which, during a long and brilliant career Sir George Airyhas conferred upon his office, and of the great services which, inconnection with, as well as in the discharge of, his duties, he hasrendered to the Crown and the Public, decide to deal with his caseunder the IXth Section of the Superannuation Act, 1859, which empowersthem to grant a special pension for special services. Accordingly my Lords are pleased to award to Sir George Biddell Airy, K. C. B. , F. R. S. , a special Retired Allowance of _£1100_ per annum. * * * * * THE WHITE HOUSE, CROOM'S HILL, GREENWICH, _1881, October 29_. SIR, I have the honour to acknowledge your letter of October 27, transmitting to me, by instruction of The Lords Commissioners ofAdmiralty, copy of a Treasury Minute dated 1881 October 10, in whichthe Lords Commissioners of Her Majesty's Treasury are pleased to awardto me an annual retired allowance of _£1100_ per annum. Acknowledging the very liberal award of the Lords Commissioners ofTreasury, and the honourable and acceptable terms in which it isannounced, I take leave at the same time to offer to Their Lordshipsof the Admiralty my recognition of Their Lordships' kindness andcourtesy in thus handing to me copy of the Treasury Minute. I have the honour to be, Sir, Your very obedient Servant, G. B. AIRY. _The Secretary of the Admiralty, _ * * * * * From the Assistants of the Royal Observatory, with whom he was indaily communication, whose faithful and laborious services he had sooften thankfully recognized in his Annual Reports to the Board ofVisitors, and to whom so much of the credit and success of theObservatory was due, he received the following address: ROYAL OBSERVATORY, GREENWICH, _1881, August 11_. DEAR SIR, We cannot allow the official relation which has so long existedbetween yourself and us to terminate without expressing to you oursense of the admirable manner in which you have, in our opinion, upheld the dignity of the office of Astronomer Royal during the manyyears that you have occupied that important post. Your long continued and varied scientific work has received suchuniversal recognition from astronomers in all lands, that it isunnecessary for us to do more than assure you how heartily we join intheir appreciation of your labours. We may however add that ourposition has given us opportunities of seeing that which others cannotequally well know, the untiring energy and great industry which havebeen therein displayed throughout a long and laborious career, anenergy which leads you in retirement, and at fourscore years of age, to contemplate further scientific work. We would ask you to carry with you into private life the best wishesof each one of us for your future happiness, and that of your family, expressing the hope that the days of retirement may not be few, andassuring you that your name will long live in our remembrance. We are, dear Sir, Yours very faithfully, W. H. M. CHRISTIE, EDWIN DUNKIN, WILLIAM ELLIS, GEORGE STRICKLAND CRISWICK, W. C. NASH, A. M. W. DOWNING, EDWARD W. MAUNDER, W. G. THACKERAY, THOMAS LEWIS. _Sir G. B. Airy, K. C. B. , &c. , &c. , Astronomer Royal. _ * * * * * ROYAL OBSERVATORY, GREENWICH, _1881, August 13_. MY DEAR MR CHRISTIE, and Gentlemen of the Royal Observatory, With very great pleasure I have received your letter of August 11. Ithank you much for your recognition of the general success of theObservatory, and of a portion of its conduct which--as you remark--canscarcely be known except to those who are every day engaged in it: butI thank you still more for the kind tone of your letter, which seemsto shew that the terms on which we have met are such as leaves, afterso many years' intercourse, no shadow of complaint on any side. Reciprocating your wishes for a happy life, and in your case aprogressive and successful one, I am, My dear Mr Christie and Gentlemen, Yours faithfully, G. B. AIRY. * * * * * Throughout his tenure of office Airy had cultivated and maintained themost friendly relations with foreign astronomers, to the greatadvantage of the Observatory. Probably all of them, at one time oranother, had visited Greenwich, and to most of them he was wellknown. On his retirement from office he received an illuminatedAddress from his old friend Otto Struve and the staff of the PulkowaObservatory, an illuminated Address from the Vorstand of theAstronomische Gesellschaft at Berlin signed by Dr Auwers and theSecretaries, a complimentary letter from the Academy of Sciences atAmsterdam, and friendly letters of sympathy from Dr Gould, Prof. Newcombe, Dr Listing, and from many other scientific friends andsocieties. His replies to the Russian and German Addresses were asfollows: ROYAL OBSERVATORY, GREENWICH, _1881, August 5_. MY DEAR SIR, I received, with feelings which I will not attempt to describe, theAddress of yourself and the Astronomers of Pulkowa generally, on theoccasion of my retirement from the office of Astronomer Royal. I canscarcely credit myself with possessing all the varied claims to yourscientific regard which you detail. I must be permitted to attributemany of them to the long and warm friendship which has subsisted solong between the Directors of the Pulkowa Observatory and myself, andwhich has influenced the feelings of the whole body of Astronomersattached to that Institution. On one point, however, I willinglyaccept your favourable expressions--I have not been sparing of mypersonal labour--and to this I must attribute partial success on someof the subjects to which you allude. In glancing over the marginal list of scientific pursuits, I remarkwith pleasure the reference to _Optics_. I still recur with delight tothe Undulatory Theory, once the branch of science on which I was bestknown to the world, and which by calculations, writings, and lectures, I supported against the Laplacian School. But the close of yourremarks touches me much more--the association of the name of W. Struveand my own. I respected deeply the whole character of your Father, andI believe that he had confidence in me. From our first meeting in 1830(on a Commission for improvement of the Nautical Almanac) I neverceased to regard him as superior to others. I may be permitted to addthat the delivery of his authority to the hands of his son has notweakened the connection of myself with the Observatory of Poulkova. Acknowledging gratefully your kindness, and that of all theAstronomers of the Observatory of Poulkova, and requesting you toconvey to them this expression, I am, my dear Sir, Yours most truly, G. B. AIRY. _To M. Otto von Struve, Director of the Observatory of Poulkova and the Astronomers of that Observatory. _ * * * * * ROYAL OBSERVATORY, GREENWICH, _1881, August 3_. MY DEAR SIR, With very great pleasure I received the Address of the AstronomischeGesellschaft on occasion of my intended resignation of the Office ofAstronomer Royal: dated July 27, and signed by yourself as Presidentand Messrs Schoenfeld and Winnecke as Secretaries of the AstronomischeGesellschaft. I thank you much for the delicacy of your arrangementfor the transmission of this document by the hands of our friend DrHuggins. And I think you will be gratified to learn that it arrived ata moment when I was surrounded by my whole family assembled at my_jour-de-fête_, and that it added greatly to the happiness of theparty. I may perhaps permit myself to accept your kind recognition of mydevotion of time and thought to the interests of my Science and myOffice. It is full reward to me that they are so recognized. As tothe success or utility of these efforts, without presuming, myself, toform an opinion, I acknowledge that the connection made by theAstronomische Gesellschaft, between my name and the advance of modernastronomy, is most flattering, and will always be remembered by mewith pride. It is true, as is suggested in your Address, that one motive for myresignation of Office was the desire to find myself more free for theprosecution of further astronomical investigations. Should my healthremain unbroken, I hope to enter shortly upon this undertaking. Again acknowledging the kindness of yourself and the Vorstand of theAstronomische Gesellschaft, and offering my best wishes for thecontinued success of that honourable institution, I am, my dear Sir, Yours very truly, G. B. AIRY. _To Dr Aimersand the Vorstand of theAstronomische Gesellschaft. _ CHAPTER X. AT THE WHITE HOUSE, GREENWICH. FROM HIS RESIGNATION OF OFFICE ON AUGUST 15TH, 1881, TO HIS DEATH ON JANUARY 2ND, 1892. HISTORY OF HIS LIFE AFTER HIS RESIGNATION OF OFFICE. On the 16th of August 1881 Airy left the Observatory which had beenhis residence for nearly 46 years, and removed to the WhiteHouse. Whatever his feelings may have been at the severing of his oldassociations he carefully kept them to himself, and entered upon hisnew life with the cheerful composure and steadiness of temper which hepossessed in a remarkable degree. He was now more than 80 years old, and the cares of office had begun to weigh heavily upon him: thelong-continued drag of the Transit of Venus work had wearied him, andhe was anxious to carry on and if possible complete his NumericalLunar Theory, the great work which for some years had occupied much ofhis time and attention. His mental powers were still vigorous, and hisenergy but little impaired: his strong constitution, his regularhabits of life, the systematic relief which he obtained by shortholiday expeditions whenever he found himself worn with work, and hiskeen interest in history, poetry, classics, antiquities, engineering, and other subjects not immediately connected with his profession, hadcombined to produce this result. And in leaving office, he had no ideaof leaving off work; his resignation of office merely meant for him achange of work. It is needless to say that his interest in the welfareand progress of the Observatory was as keen as ever; his advice wasalways at the service of his successor, and his appointment as Visitora year or two after his resignation gave him an official position withregard to the Observatory which he much valued. The White House, whichwas to be his home for the rest of his life, is just outside one ofthe upper gates of the Park, and about a quarter of a mile from theObservatory. Here he resided with his two unmarried daughters. Thehouse suited him well and he was very comfortable there: he preferredto live in the neighbourhood with which he was so familiar and inwhich he was so well known, rather than to remove to a distance. Hisdaily habits of life were but little altered: he worked steadily asformerly, took his daily walk on Blackheath, made frequent visits toPlayford, and occasional expeditions to the Cumberland Lakes andelsewhere. The work to which he chiefly devoted himself in his retirement was thecompletion of his Numerical Lunar Theory. This was a vast work, involving the subtlest considerations of principle, very long andelaborate mathematical investigations of a high order, and an enormousamount of arithmetical computation. The issue of it was unfortunate:he concluded that there was an error in some of the early work, whichvitiated the results obtained: and although the whole process waspublished, and was left in such a state that it would be acomparatively simple task for a future astronomer to correct andcomplete it, yet it was not permitted to the original author of it todo this. To avoid the necessity of frequent reference to this work inthe history of Airy's remaining years, it will be convenient tosummarize it here. It was commenced in 1872: "On Feb. 23rd in thisyear I first (privately) formed the notion of preparing a NumericalLunar Theory by substituting Delaunay's numbers in the properEquations and seeing what would come of it. " From this time forwardtill his power to continue it absolutely failed, he pursued thesubject with his usual tenacity of purpose. During his tenure ofoffice every available opportunity was seized for making progress withhis Lunar Theory, and in every Report to the Visitors a carefulstatement was inserted of the state in which it then stood. And, afterhis resignation of office, it formed the bulk of his occupation. In1873 the Theory was formed, and by 1874 it was so far advanced that hepublished in the Monthly Notices of the Royal Astronomical Society astatement of the fundamental points of the Theory. In 1875, theTheory having advanced to a stage where extensive arithmeticalcomputation was required, he obtained a small grant from theGovernment in aid of the expense of the work, and other grants weremade in subsequent years. By 1878 the calculations were so faradvanced that an opinion could be formed as to the probable accuracyof the Theory, and the following remark is made: "A cursory collationof the terms relating to the Areas (in the Ecliptic) led me to supposethat there might be some error in the computations of the AnnualEquation and related terms;" but no error could be discovered and thework proceeded. The complex character of the Theory, and the extremecare required in the mathematical processes, are well illustrated bythe following statement, which occurs in the Report of 1879, "Animportant error in the theoretical formulae for Variations of RadiusVector, Longitude, and Latitude, was discovered; some calculationsdepending on them are cancelled. " In 1880 and 1881 the work wascontinued, but was "sadly interrupted by the pressure of the Transitof Venus work and other business. " After his resignation of the Officeof Astronomer Royal he had no further public assistance, and did muchof the computations himself, but a sum of _£100_ was contributed by MrDe La Rue in furtherance of the work, and this sum was spent oncomputers. In his retirement the work made good progress, and onDec. 31st, 1882, he made the following note: "I finished and put ingeneral order the final tables of Equations of Variations. This is adefinite point in the Lunar Theory. . . . I hope shortly to take upseverely the numerical operations of the Lunar Theory from the verybeginning. " The work was continued steadily through 1883, and onMar. 24th, 1884, he made application through the Board of Visitors tothe Admiralty to print the work: after the usual enquiries as to theexpense this was acceded to, and copy was sent to the printers as soonas it was ready. The first printed proofs were received on Feb. 5th, 1885, and the whole book was printed by the end of 1886. From thefrequent references in his journal to errors discovered and correctedduring the progress of these calculations, it would seem likely thathis powers were not what they had been, and that there was aprobability that some important errors might escape correction. Hewas far too honest to blind himself to this possibility, and in thePreface to his Numerical Lunar Theory he says thus: "I have explainedabove that the principle of operations was, to arrange the fundamentalmechanical equations in a form suited for the investigations of LunarTheory; to substitute in the terms of these equations the numericalvalues furnished by Delaunay's great work; and to examine whether theequations are thereby satisfied. With painful alarm, I find that theyare not satisfied; and that the discordance, or failure of satisfyingthe equations, is large. The critical trial depends on the great massof computations in Section II. These have been made in duplicate, withall the care for accuracy that anxiety could supply. Still I cannotbut fear that the error which is the source of discordance must be onmy part. I cannot conjecture whether I may be able to examinesufficiently into this matter. " He resolutely took in hand therevision of his work, and continued it till October 1888. But it isclear from the entries in his journal that his powers were now unequalto the task, and although from time to time he suspected that he haddiscovered errors, yet it does not appear that he determined anythingwith certainty. He never doubted that there were important errors inthe work, and later on he left the following private note on thesubject: NUMERICAL LUNAR THEORY. _1890, Sept. 29_. I had made considerable advance (under official difficulties) incalculations on my favourite Numerical Lunar Theory, when I discoveredthat, under the heavy pressure of unusual matters (two Transits ofVenus and some eclipses) I had committed a grievous error in the firststage of giving numerical value to my Theory. My spirit in the work was broken, and I have never heartily proceededwith it since. G. B. AIRY. Probably the error referred to here is the suspected error mentionedabove in his Report of 1878, as to which he subsequently became morecertain. Whatever may be the imperfections of the Numerical Lunar Theory, it isa wonderful work to have been turned out by a man 85 years old. In itsidea and inception it embodies the experience of a long life activelyspent in practical science. And it may be that it will yet fulfil theobjects of its author, and that some younger astronomer may take itup, correct its errors (wherever they may be), and fit it forpractical use. And then the labour bestowed upon it will not havebeen in vain. Subject always to the absorbing occupations of the Lunar Theory heamused himself with reading his favourite subjects of History andAntiquities. His movements during the remainder of the year 1881 wereas follows: In September he paid a two days' visit to Lady Herschel atHawkhurst. From Oct. 4th to 17th he was at the Cumberland Lakes andengaged in expeditions in the neighbourhood. From Nov. 5th to 8th hewas at Cambridge, inspecting Prof. Stuart's workshops, and otherscientific institutions. On Dec. 13th he went to Playford. --Amongstmiscellaneous matters: in November he wrote to Mr Rothery on the lossof the 'Teuton' at some length, with suggestions for the saferconstruction of such vessels. --In October he was asked for suggestionsregarding the establishment of a "Standard Time" applicable to therailway traffic in the United States: he replied as follows: _1881, Oct. 31_. SIR, I have to acknowledge your letter of October 17, introducing to mynotice the difficulty which appears to be arising in America regardinga "Standard Time, " for extensive use throughout N. America"applicable to railway traffic only. " The subject, as includingconsiderations of convenience in all the matters to which it applies, is one of difficulties probably insuperable. The certainty, however, that objections may be raised to every scheme, renders me less timidin offering my own remarks; which are much at your service. I first comment upon your expression of "Standard Time. . . Applicableto railway traffic only. " But do you mean this as affecting thetransactions between one railway and another railway, or as affectingeach railway and the local interests (temporal and others) of thetowns which it touches? The difference is so great that I should bedisposed to adopt it as marking very strongly the difference to bemade between the practices of railways among themselves and thepractices of railways towards the public; and will base a system onthat difference. As regards the practices of railways among themselves: if the variousrailways of America are joined and inosculated as they are in England, it appears to me indispensable that they have one common standard_among themselves_: say Washington Observatory time. But this is onlyneeded for the office-transactions between the railways; it may bekept perfectly private; never communicated to the public at all. And Ishould recommend this as the first step. There will then be no difficulty in deducing, from these privateWashington times, the accurate local times at those stations (whoselongitude is supposed to be fairly well known, as a sailor with asextant can determine one in a few hours) which the railwayauthorities may deem worthy of that honour; generally the termini ofrailways. Thus we shall have a series of bases of local time, ofauthoritative character, through the country. Of such bases _we_ have two, Greenwich and Dublin: and they areseparated by a sea-voyage. In the U. S. Of America there must be agreater number, and probably not so well separated. Still it isindispensable to adopt such a system of local centers. No people in this world can be induced to use a reckoning which doesnot depend clearly upon the sun. In all civilized countries it depends(approximately) on the sun's meridian passage. Even the sailor onmid-ocean refers to that phenomenon. And the solar passage, withreasonable allowance, 20m. Or 30m. One way or another, must berecognized in all time-arrangements as giving the fundamentaltime. The only practical way of doing this is, to adopt for a wholeregion the fundamental time of a center of that region. And to this fundamental time, the local time of the railway, as nowentering into all the concerns of life, must be adapted. A solicitorhas an appointment to meet a client by railway; a physician to aconsultation. How is this to be kept if the railway uses one time andevery other act of life another? There is one chain of circumstances which is almost peculiar--that ofthe line from New York to San Francisco. Here I would have two clocksat every station: those on the north side all shewing San Franciscotime, and those on the south all shewing New York time. Everytraveller's watch would then be available to the end of his journey. A system, fundamentally such as I have sketched, would give littletrouble, and may I think be adopted with advantage. I am, Sir, Your faithful servant, G. B. AIRY. _Mr Edward Barrington. _ 1882 He returned from Playford on Jan. 17: his other movements during theyear were as follows: from Apr. 27th to May 11th he was at Playford;and again from August 1st to 24th. From Oct. 9th to Nov. 1st he wastravelling with his two unmarried daughters in the Lake District ofCumberland: the journey was by Furness and Coniston to Portinscalenear Keswick; on Oct. 13th he fell and sprained his ankle, and hisexcursions for the rest of the time were mainly conducted bydriving. Shortly after his return, on Nov. 11th, while walking aloneon Blackheath, he was seized with a violent attack of illness, and layhelpless for some time before he was found and brought home: he seemshowever to have recovered to a great extent in the course of a day ortwo, and continued his Lunar Theory and other work as before. On June22nd he made the following sad note, "This morning, died after a mostpainful illness my much-loved daughter-in-law, Anna Airy, daughter ofProfessor Listing of Göttingen, wife of my eldest son Wilfrid. " InFebruary he wrote out his reminiscences of the village of Playfordduring his boyhood. In June he was much disturbed in mind on hearing of some importantalterations made by the Astronomer Royal in the Collimators of theTransit Circle, and some correspondence ensued on the subject. --Duringthe year he had much correspondence on the subject of the subsidenceson Blackheath. The following letter was written in reply to a gentleman who had askedwhether it could be ascertained by calculation how long it is sincethe Glacial Period existed: _1882, July 4_. SIR, I should have much pleasure in fully answering your questions of July3 if I were able to do so: but the subject really is very obscure. (1) Though it is recognized that the glacial period (or periods) islate, I do not think that any one has ventured to fix upon a rudenumber of years since elapsed. (2) We have no reason to think that the mean distance of the earthfrom the sun has sensibly altered. There have been changes in theeccentricity of the orbit (making the earth's distance from the sunless in one month and greater in the opposite month), but I do notperceive that this would explain glaciers. (3) I consider it to be certain that the whole surface of the earth, at a very distant period, was very hot, that it has cooled gradually, and (theoretically and imperceptibly) is cooling still. The glaciersmust be later than these hot times, and later than our lastconsolidated strata: but this is nearly all that I can say. I am, Sir, Your obedient Servant, G. B. AIRY. _James Alston, Esq. _ 1883 From May 2nd to 29th he was at Playford. From July 10th to 20th he wastravelling in South Wales with his daughters. --From Oct. 10th toNov. 10th he was at Playford. --Between Nov. 20th of this year andJan. 4th of the year 1884, he sat several times to Mr John Collier forhis portrait: the picture was exhibited in the Academy of 1884; it isa most successful and excellent likeness. Throughout the year he was very busy with the Numerical LunarTheory. --In March he was officially asked to accept the office ofVisitor of the Royal Observatory, which he accepted, and in thiscapacity attended at the Annual Visitation on June 2nd, and addresseda Memorandum to the Visitors on the progress of his Lunar Theory. --OnMarch 12th he published in several newspapers a statement inopposition to the proposed Braithwaite and Buttermere Railway, whichhe considered would be injurious to the Lake District, in which hetook so deep an interest. --In May he communicated to "The Observatory"a statement of his objections to a Theory advanced by Mr Stone (thenPresident of the Royal Astronomical Society) to account for therecognized inequality in the Mean Motion of the Moon. This Theory, ona subject to which Airy had given his incessant attention for so manyyears, would naturally receive his careful attention and criticism, and it attracted much general notice at the time. --In December hewrote to the Secretary of the Royal Astronomical Society his opinionas to the award of the Medal of the Society. In this letter he statedthe principles which guided him as follows: "I have always maintainedthat the award of the Medal ought to be guided mainly by theoriginality of communications: that one advance in a new directionought in our decision to outweigh any mass of work in a routinealready established: and that, in any case, scientific utility asdistinguished from mere elegance is indispensable. "--In JulyLieut. Pinheiro of the Brazilian Navy called with an autograph letterof introduction from the Emperor of Brazil. The Lieutenant desired tomake himself acquainted with the English system of Lighthouses andMeteorology, and Airy took much trouble in providing him withintroductions through which he received every facility for thethorough accomplishment of his object. --On Oct. 8th he forwarded toProf. Cayley proofs of Euclid's Propositions I. 47 and III. 35 withthe following remarks: "I place on the other side the propositionswhich may be substituted (with knowledge of Euclid's VI. Book) for thetwo celebrated propositions of the geometrical books. They leave on mymind no doubt whatever that they were invented as proofs by ratios, and that they were then violently expanded into cumbrous geometricalproofs. "--On June 28th he declined to sign a memorial asking for theinterment of Mr Spottiswoode in Westminster Abbey, stating as hisreason, "I take it, that interment possessing such a public characteris a public recognition of benefits, political, literary, orphilosophical, whose effects will be great and durable. Now I doubtwhether it can be stated that Mr Spottiswoode had conferred suchbenefits on Society. "But he adds at length his cordial recognition ofMr Spottiswoode's scientific services. --Throughout his life Airy was aregular attendant at church, and took much interest in the conduct ofthe Church services. In October of this year he wrote a long letterto the Vicar of Greenwich on various points, in which occurs thefollowing paragraph: "But there is one matter in the present form ofthe Church Service, on which my feeling is very strong, namely the(so-called, I believe) Choral Service, in the Confession, the Prayer, and the Creed. I have long listened with veneration to our nobleLiturgy, and I have always been struck with the deep personallyreligious feeling which pervades it, especially those parts of itwhich are for 'The People. ' And an earnest Priest, earnestly pressingthese parts by his vocal example on the notice of the People, canscarcely fail to excite a corresponding earnestness in them. All thisis totally lost in the choral system. For a venerable persuasion thereis substituted a rude irreverential confusion of voices; for anearnest acceptance of the form offered by the Priest there issubstituted--in my feeling at least--a weary waiting for the end of anunmeaning form. " He also objected much to singing the responses to theCommandments. 1884 From Apr. 29th to May 30th he was at Playford, concluding his Journalthere with the note "So ends a pleasant Vacation. "--On June 11th hewent to Cambridge and attended the Trinity College CommemorationService, and dined in Hall. --From Aug. 14th to Sept. 11th he was atPlayford. --On Sept. 26th he made an expedition to Guildford andFarnham. --During this year he was closely engaged on the NumericalLunar Theory, and for relaxation was reading theology and sundry booksof the Old Testament. On June 7th he attended at the Visitation of the RoyalObservatory. --In a letter written in April to Lt. -Col. Marindin, R. A. , on the subject of wind pressure there occurs the following remark:"When the heavy gusts come on, the wind is blowing in directionschanging rapidly, but limited in extent. My conclusion is that inarches of small extent (as in the Tay Bridge) every thing must becalculated for full pressure; but in arches of large extent (as in theForth Bridge) every thing may be calculated for small pressure. Andfor a suspension bridge the pressure is far less dangerous than for astiff arch. "--In January he had some correspondence with ProfessorTyndall on the Theory of the "White Rainbow, " and stated that hethoroughly agreed with Dr Young's explanation of this phaenomenon. --The following is extracted from a letter on May 1st tohis old friend Otto Struve: "I received from you about 3 or 4 weekspast a sign of your friendly remembrance, a copy of your paper on theAnnual Parallax of Aldebaran. It pleased me much. Especially I wasdelighted with your noble retention of the one equation whose resultdiffered so sensibly from that of the other equations. It is quitepossible, even probable, that the mean result is improved by it. Ihave known such instances. The first, which attracted much attention, was Capt. Kater's attempt to establish a scale of longitude in Englandby reciprocal observations of azimuth between Beachy Head andDunnose. The result was evidently erroneous. But Colonel Colby, onexamination of the original papers, found that some observations hadbeen omitted, as suspicious; and that when these were included themean agreed well with the scale of observation inferred from othermethods. "--In a letter to the Rev. R. C. M. Rouse, acknowledging thereceipt of a geometrical book, there occurs the following paragraph:"I do not value Euclid's Elements as a super-excellent book ofinstruction--though some important points are better presented in itthan in any other book of geometrical instruction that I haveseen. But I value it as a book of strong and distinct reasoning, andof orderly succession of reasonings. I do not think that there is anybook in the world which presents so distinctly the 'because. . . . . . Therefore. . . . . . . ' And this is invaluable for the mentaleducation of youth. "--In May he was in correspondence with ProfessorBalfour Stewart regarding a projected movement in TerrestrialMagnetism to be submitted to the British Association. Airy cordiallyapproved of this movement, and supported it to the best of hisability, stating that in his opinion what was mainly wanted was thecollation of existing records. --In January and February he was muchpressed by Prof. Pritchard of Oxford to give his opinion as to theincorrectness of statements made by Dr Kinns in his Lectures on theScientific Accuracy of the Bible. Airy refused absolutely to take partin the controversy, but he could not escape from the correspondencewhich the matter involved: and this led up to other points connectedwith the early history of the Israelites, a subject in which he tookmuch interest. 1885 From May 4th to June 3rd he was at Playford. --From July 2nd to 22nd hewas in the Lake District. The journey was by Windermere to Kentmere, where he made enquiries concerning the Airy family, as it had beenconcluded with much probability from investigations made by hisnephew, the Rev. Basil R. Airy, that the family was settled there at avery early date. Some persons of the name of Airy were still livingthere. He then went on by Coniston and Grasmere to Portinscale, andspent the rest of his time in expeditions amongst the hills and visitsto friends. --On July 28th he went to Woodbridge in Suffolk anddistributed the prizes to the boys of the Grammar School there. --FromOct. 9th to Nov. 12th he was again at Playford. --Throughout the yearhe was busily engaged on the Numerical Lunar Theory, and found butlittle time for miscellaneous reading. Of printed papers by Airy in this year the most important was one onthe "Results deduced from the Measures of Terrestrial Magnetic Forcein the Horizontal Plane, " &c. This was a long Paper, communicated tothe Royal Society, and published in the Phil. Trans. , and was the lastScientific Paper of any importance (except the Volume of the NumericalLunar Theory) in the long list of "Papers by G. B. Airy. " Thepreparation of this Paper took much time. --Of miscellaneous matters:In May a Committee of the Royal Society had been appointed to advisethe India Office as to the publication of Col. J. Herschel's pendulumobservations in India; and Airy was asked to assist the Committee withhis advice. He gave very careful and anxious consideration to thesubject, and it occupied much time. --In the early part of the year hewas asked by Sir William Thomson to assist him with an affidavit in alawsuit concerning an alleged infringement of one of his Patents forthe improvement of the Compass. Airy declined to make an affidavit orto take sides in the dispute, but he wrote a letter from which thefollowing is extracted: "I cannot have the least difficulty inexpressing my opinion that you have made a great advance in theapplication of my method of correcting the compass in iron ships, byyour introduction of the use of short needles for the compass-cards. In my original investigations, when the whole subject was in darkness, I could only use existing means for experiment, namely the long-needlecompasses then existing. But when I applied mechanical theory toexplanation of the results, I felt grievously the deficiency of atheory and the construction which it suggested (necessarily founded onassumption that the proportion of the needle-length to the otherelements of measure is small) when the length of the needles wasreally so great. I should possibly have used some construction likeyours, but the Government had not then a single iron vessel, and didnot seem disposed to urge the enquiry. You, under happier auspices, have successfully carried it out, and, I fully believe, with muchadvantage to the science. "--He wrote a Paper for the Athenaeum and hadvarious correspondence on the subject of the Badbury Rings inDorsetshire, which he (and others) considered as identical with the"Mons Badonicus" of Gildas, the site of an ancient British battle. --InFebruary he was in correspondence with the Astronomer Royal on UniformTime Reckoning, and on considerations relating to it. --On June 6th heattended the Annual Visitation of the Observatory, and brought beforethe Board his investigations of the Diurnal Magnetic Inequalities, andthe revises of his Lunar Theory. 1886 From June 8th to July 17th he was at Playford. --And again at Playfordfrom Oct. 5th to Nov. 8th. --On March 27th he had an attack of gout inhis right foot, which continued through April and into May, causinghim much inconvenience. --He was busy with the Numerical Lunar Theoryup to Sept. 25th, when he was reading the last proof-sheet receivedfrom the printers: during this period his powers were evidentlyfailing, and there are frequent references to errors discovered andcorrected, and to uncertainties connected with points of theTheory. But his great work on the Numerical Lunar Theory was printedin this year: and there can be no doubt that he experienced a greatfeeling of relief when this was accomplished. --He was incorrespondence with Prof. Adams as to the effect of his reduction ofthe Coefficient of Lunar Acceleration on the calculation of theancient historical eclipses. --He compiled a Paper "On theestablishment of the Roman dominion in England, " which was printed in1887. --He wrote a notice concerning events in the life of Mr JohnJackson of Rosthwaite near Keswick, a well-known guide andmuch-respected authority on matters relating to the Lake District. --Healso wrote a short account of the connection of the history of Mdllede Quéroualle with that of the Royal Observatory at Greenwich. --OnJune 4th he attended at the Annual Visitation of the Observatory. 1887 On May 9th to 11th he made a short visit to Eastbourne and theneighbourhood. --From June 8th to July 13th he was at Playford. --FromAug. 29th to Sept. 5th he was travelling in Dorsetshire and Wiltshire:he went first to Weymouth, a very favourite centre for excursions withhim, and afterwards visited Bridport and Lyme Regis: then byDorchester to Blandford, and visited the Hod Hill, Badbury Rings, &c. :at Wimborne he was much interested in the architecture of the church:lastly he visited Salisbury, Old Sarum, Stonehenge, &c. , and returnedto Greenwich. --From Oct. 11th to Nov. 12th he was at Playford. --Duringthis year he partly occupied himself with arranging his papers anddrawings, and with miscellaneous reading. But he could not withdrawhis thoughts from his Lunar Theory, and he still continued to strugglewith the difficulties of the subject, and was constantly schemingimprovements. His private accounts also now gave him muchtrouble. Throughout his life he had been accustomed to keep hisaccounts by double entry in very perfect order. But he now began tomake mistakes and to grow confused, and this distressed himgreatly. It never seemed to occur to him to abandon his elaboratesystem of accounts, and to content himself with simple entries ofreceipts and expenses. This would have been utterly opposed to hissense of order, which was now more than ever the ruling principle ofhis mind. And so he struggled with his accounts as he did with hisLunar Theory till his powers absolutely failed. In his Journal forthis year there are various entries of mental attacks of shortduration and other ailments ascribable to his advanced age. The last printed "Papers by G. B. Airy" belong to this year. One wasthe Paper before referred to "On the establishment of the Romandominion in England": another was on the solution of a certainEquation: and there were early reminiscences of the Cambridge Tripos, &c. --In February he attended a little to a new edition of his IpswichLectures, but soon handed it over to Mr H. H. Turner of the RoyalObservatory. --On May 23rd he was drawing up suggestions for thearrangement of the Seckford School, &c. , at Woodbridge. --On June 4thhe attended the Visitation of the Royal Observatory, when a resolutionwas passed in favour of complete photography of the star-sky. 1888 From the 14th to 16th of May he made a short expedition toBournemouth, and stopped on the way home to visit WinchesterCathedral. --From June 27th to Aug. 3rd he was at Playford; and againfrom Oct. 13th to Nov. 10th. --During the first half of the year hecontinued his examination of his Lunar Theory, but gradually droppedit. There are several references in his Journal to his feelings ofpain and weakness, both mental and bodily: at the end of March he hadan attack of gout in the fingers of his right hand. During the latterpart of the year he was troubled with his private accounts, asbefore. --He does not appear to have been engaged on any miscellaneousmatters calling for special notice in this year. But he kept up hisastronomical correspondence--with Lockyer on the meteorite system ofplanetary formation; with Pritchard on the work of the OxfordUniversity Observatory; with Adams on his Numerical Lunar Theory, &c. , and with others. --On June 2nd he attended the Visitation of the RoyalObservatory. --He amused himself occasionally with reading hisfavourite subjects of history and antiquities, and with looking oversome of his early investigations of scientific questions. 1889 On June 5th he made a one-day's excursion to Colchester. --From July2nd to 27th he was in the Cumberland Lake District, chiefly atPortinscale near Keswick. While staying at Portinscale he was seizedwith a sudden giddiness and fell upon the floor: he afterwards wrote acurious account of the visions which oppressed his brain immediatelyafter the accident. He returned by Solihull, where his son Osmund wasresiding. --From Oct. 4th to Nov. 8th he was at Playford. While therehe drew up a short statement of his general state of health, advertingparticularly to the loss of strength in his legs and failure of hiswalking powers. --His health seems to have failed a good deal in thisyear: on Feb. 4th he had an accidental fall, and there are severalentries in his Journal of mental attacks, pains in his limbs, affection of his eye-sight, &c. --In the early part of the year he wasmuch engaged on the history of the Airy family, particularly on thatof his father. --In this year the White House was sold by auction byits owners, and Airy purchased it on May 24th. --He was still indifficulties with his private accounts, but was making efforts toabandon his old and elaborate system. --For his amusement he waschiefly engaged on Theological Notes which he was compiling: and alsoon early optical investigations, &c. On June 1st he attended the Visitation of the Royal Observatory, andmoved a resolution that a Committee be appointed to consider whetherany reduction can be effected in the amount of matter printed in theVolume of Observations of the Royal Observatory. During his tenure ofoffice he had on various occasions brought this subject before theBoard of Visitors, and with his usual tenacity of purpose he now asVisitor pressed it upon their notice. --In May he zealously joined withothers in an application to get for Dr Huggins a pension on the CivilList. --In January he prepared a short Paper illustrated with diagramsto exhibit the Interference of Solar Light, as used by him in hisLectures at Cambridge in 1836: but it does not appear to have beenpublished. --In April he received a copy of a Paper by Mr Rundell, referring to the complete adoption of his system of compass correctionin iron ships, not only in the merchant service, but also in theNavy. This was a matter of peculiar gratification to Airy, who hadalways maintained that the method of Tables of Errors, which had beenso persistently adhered to by the Admiralty, was a mistake, and thatsooner or later they would find it necessary to adopt his method ofmechanical correction. The passage referred to is as follows: "Thename of Sir George Airy, the father of the mechanical compensation ofthe compass in iron vessels, having just been mentioned, it may not beinappropriate to remind you that the present year is the fiftiethsince Sir George Airy presented to the Royal Society his celebratedpaper on this subject with the account of his experiments on the'Rainbow' and 'Ironsides. ' Fifty years is a long period in one man'shistory, and Sir George Airy may well be proud in looking back overthis period to see how complete has been the success of his compassinvestigation. His mode of compensation has been adopted by all thecivilized world. Sir William Thomson, one of the latest and perhapsthe most successful of modern compass adjusters, when he exhibited hisapparatus in 1878 before a distinguished meeting in London, remarkedthat within the last ten years the application of Sir George Airy'smethod had become universal, not only in the merchant service, but inthe navies of this and other countries, and added--The compass and thebinnacles before you are designed to thoroughly carry out in practicalnavigation the Astronomer Royal's principles. " 1890 From May 17th to 24th he was on an expedition to North Wales, stoppingat Chester, Conway, Carnarvon, Barmouth, and Shrewsbury. --From June18th to July 24th he was at Playford; and again from Oct. 11th toNov. 15th. --In this year his powers greatly failed, and he complainedfrequently of mental attacks, weakness of limbs, lassitude, andfailure of sleep. He occupied himself as usual with his books, papers, and accounts; and read Travels, Biblical History, &c. , but nothingvery persistently. On June 7th he attended the Visitation of the Royal Observatory. --Froma letter addressed to him by Mr J. Hartnup, of Liverpool Observatory, it appears that there had grown up in the mercantile world animpression that very accurate chronometers were not needed for steamships, because they were rarely running many days out of sight ofland: and Airy's opinion was requested on this matter. He replied asfollows on Mar. 3rd: "The question proposed in your letter is purely apractical one. (1) If a ship is _likely_ ever to be two days out ofsight of land, I think that she ought to be furnished with two _good_chronometers, properly tested. (2) For the proper testing of the ratesof the chronometers, a rating of the chronometers for three or fourdays in a meridional observatory is necessary. A longer testing isdesirable. "--In March he was in correspondence, as one of the Trusteesof the Sheepshanks Fund, with the Master of Trinity relative to grantsfrom the Fund for Cambridge Observatory. 1891 From June 16th to July 15th he was at Playford. And again fromOct. 12th to Dec. 2nd (his last visit). Throughout the year hisweakness, both of brain power and muscular power, had been graduallyincreasing, and during this stay at Playford, on Nov. 11th, he felldown in his bed-room (probably from failure of nerve action) and wasmuch prostrated by the shock. For several days he remained in asemi-unconscious condition, and although he rallied, yet he continuedvery weak, and it was not until Dec. 2nd that he could be removed tothe White House. Up to the time of his fall he had been able to takefrequent drives and even short walks in the neighbourhood that he wasso fond of, but he could take but little exercise afterwards, and onor about Nov. 18th he made the following note: "The saddest expeditionthat I have ever made. We have not left home for several days. " The rapid failure of his powers during this year is well exemplifiedby his handwriting in his Journal entries, which, with occasionalrallies, becomes broken and in places almost illegible. He makesfrequent reference to his decline in strength and brain-power, and tohis failing memory, but he continued his ordinary occupations, madefrequent drives around Blackheath, and amused himself with his familyhistory researches, arrangement of papers, and miscellaneous reading:and he persisted to the last with his private accounts. His interestin matters around him was still keen. On June 13th he was drivingalong the Greenwich Marshes in order to track the course of the greatsewer; and on August 5th he visited the Crossness Sewage Works andtook great interest in the details of the treatment of the sewage. --InMarch he contributed, with great satisfaction, to the Fund for thePortrait of his old friend Sir G. G. Stokes, with whom he had had somuch scientific correspondence. --On July 25th an afternoon party wasarranged to celebrate the 90th anniversary of his birthday (the actualanniversary was on July 27th). None of his early friends were there:he had survived them all. But invitations were sent to all hisscientific and private friends who could be expected to come, and alarge party assembled. The afternoon was very fine, and he sat in thegarden and received his friends (many of whom had come from longdistances) in good strength and spirits. It was a most successfulgathering and was not without its meaning; for it was felt that, underthe circumstances of his failing powers, it was in all probability afinal leave-taking. --On July 27th he went down to the Greenwich ParishChurch at 9 p. M. , to be present at the illumination of the churchclock face for the first time--a matter of local interest which hadnecessitated a good deal of time and money. On this occasion at therequest of the company assembled in and around the Vestry he spoke forabout a quarter of an hour on Time--the value of accurate time, thedissemination of Greenwich time throughout the country by time-signalsfrom the Observatory, and the exhibition of it by time-balls, &c. , &c. , --the subject to which so large a part of his life had beendevoted. It was a pleasant and able speech and gave great satisfactionto the parishioners, amongst whom he had lived for so many years. --Hereceived two illuminated addresses--one from the Astronomer Royal andStaff of the Royal Observatory; the other from the Vorstand of theAstronomische Gesellschaft at Berlin--and various private letters ofcongratulation. The address from the Staff of the Observatory wasworded thus: "We, the present members of the Staff of the RoyalObservatory, Greenwich, beg to offer you our most sincerecongratulations on the occasion of your 90th birthday. We cannot butfeel how closely associated we are with you, in that our wholeenergies are directed to the maintenance and development of thatpractical astronomical work, of which you essentially laid thefoundation. It affords us great pleasure to think that after theconclusion of your life's work, you have been spared to live so longunder the shadow of the noble Observatory with which your name wasidentified for half a century, and with which it must ever remainassociated. " After his return from Playford he seemed to rally a little: but hesoon fell ill and was found to be suffering from hernia. Thisnecessitated a surgical operation, which was successfully performed onDec. 17th. This gave him effectual relief, and after recovering fromthe immediate effects of the operation, he lay for several daysquietly and without active pain reciting the English poetry with whichhis memory was stored. But the shock was too great for his enfeebledcondition, and he died peacefully in the presence of his six survivingchildren on Jan. 2nd, 1892. He was buried in Playford churchyard onJan. 7th. The funeral procession was attended at Greenwich by thewhole staff of the Royal Observatory, and by other friends, and at hisburial there were present two former Fellows of the College to whichhe had been so deeply attached. APPENDIX. LIST OF PRINTED PAPERS BY G. B. AIRY. LIST OF BOOKS WRITTEN BY G. B. AIRY. PRINTED PAPERS BY G. B. AIRY. With the instinct of order which formed one of his chiefcharacteristics Airy carefully preserved a copy of every printed Paperof his own composition. These were regularly bound in large quartovolumes, and they are in themselves a striking proof of his wonderfuldiligence. The bound volumes are 14 in number, and they occupy a spaceof 2 ft. 6 in. On a shelf. They contain 518 Papers, a list of which isappended, and they form such an important part of his life's work, that his biography would be very incomplete without a reference tothem. He was very careful in selecting the channels for the publication ofhis Papers. Most of the early Papers were published in theTransactions of the Cambridge Philosophical Society, but several ofthe most important, such as his Paper "On an inequality of long periodin the motions of the Earth and Venus, " were published in thePhilosophical Transactions of the Royal Society, and others, such asthe articles on "The Figure of the Earth, " "Gravitation, " "Tides andWaves, " &c. , were published in Encyclopaedias. After his removal toGreenwich nearly all his Papers on scientific subjects (exceptastronomy), such as Tides, Magnetism, Correction of the Compass, &c. , &c. , were communicated to the Royal Society, and were published in thePhilosophical Transactions. But everything astronomical was reservedfor the Royal Astronomical Society. His connection with that Societywas very close: he had joined it in its earliest days (the date of hiselection was May 9th, 1828), and regarded it as the proper medium forthe discussion of current astronomical questions, and for recordingastronomical progress. He was unremitting in his attendance at theMonthly Meetings of the Society, and was several times President. Inthe Memoirs of the Society 35 of his Papers are printed, and inaddition 129 Papers in the Monthly Notices. In fact a meeting of theSociety rarely passed without some communication from him, and suchwas his wealth of matter that sometimes he would communicate as manyas 3 Papers on a single evening. For the publication of several shortmathematical Papers, and especially for correspondence on disputedpoints of mathematical investigation, he chose as his vehicle thePhilosophical Magazine, to which he contributed 32 Papers. Investigations of a more popular character he published in theAthenaeum, which he also used as a vehicle for his replies to attackson his work, or on the Establishment which he conducted: in all hemade 55 communications to that Newspaper. To various Societies, suchas the Institution of Civil Engineers, the British Association, theRoyal Institution, &c. , he presented Papers or made communications onsubjects specially suited to each; and in like manner to variousNewspapers: there were 58 Papers in this category. In so long anofficial life there would naturally be a great number of OfficialReports, Parliamentary Returns, &c. , and these, with othermiscellaneous Papers printed for particular objects and for a limitedcirculation, amounted in all to 141. Under this head come his AnnualReports to the Board of Visitors, which in themselves contain anextremely full and accurate history of the Observatory during histenure of office. There are 46 of these Reports, and they would ofthemselves form a large volume of about 740 pages. The following summary of his Printed Papers shews the manner in whichthey were distributed: SUMMARY OF PRINTED PAPERS BY G. B. AIRY. Number of Papers. In the Transactions of the Cambridge Philosophical Society 30 In the Philosophical Transactions of the Royal Society 29 In the Proceedings of the Royal Society 9 In the Memoirs of the Royal Astronomical Society 35 In the Monthly Notices of the Royal Astronomical Society 129 In the Philosophical Magazine and Journal 32 In the Athenaeum 55 In Encyclopedias, and in various Newspapers and Transactions 58 In Official Reports, Addresses, Parliamentary Returns, Evidence before Committees, Lectures, Letters, Sundry Treatises, and Papers 141 --- Total 518 PRINTED PAPERS BY G. B. AIRY. Date when reador published. Title of Paper. Where published. 1822 Nov. 25 On the use of Silvered Glass for the Mirrors Camb. Phil. Soc. Of Reflecting Telescopes. 1824 Mar. 15 On the Figure assumed by a Fluid Homogeneous Camb. Phil. Soc. Mass, whose Particles are acted on by their mutual Attraction, and by small extraneous Forces. 1824 May 17 On the Principles and Construction of the Camb. Phil. Soc. Achromatic Eye-Pieces of Telescopes, and on the Achromatism of Microscopes. 1824 Trigonometry. Encycl. Metrop. 1825 Feb. 21 On a peculiar Defect in the Eye, and a Camb. Phil. Soc. Mode of correcting it. 1825 May 2 On the Forms of the Teeth of Wheels. Camb. Phil. Soc. 1826 May 8 On Laplace's Investigation of the Attraction Camb. Phil. Soc. Of Spheroids differing little from a Sphere. 1826 June 15 On the Figure of the Earth. Phil. Trans. 1826 Nov. 26 On the Disturbances of Pendulums and Camb. Phil. Soc. Balances, and on the Theory of Escapements. 1827 Feb. 15 Remarks on a Correction of the Solar Phil. Trans. Tables, required by Mr South's observations. 1827 May 9 On some Passages in Mr Ivory's Remarks Phil. Mag. On a Memoir by M. Poisson relating to the Attraction of Spheroids. 1827 May 14 On the Spherical Aberration of the Camb. Phil. Soc. May 21 Eyepieces of Telescopes. 1827 Dec. 6 On the corrections in the elements of Phil. Trans. Delambre's Solar Tables required by the observations made at the Royal Observatory, Greenwich. 1828 Feb. 26 Address to the Members of the Senate, on an Improvement in the Position of the Plumian Professor. 1828 Nov. 24 On the Longitude of the Cambridge Observatory. Camb. Phil. Soc. 1829 Nov. 13 On a method of determining the Mass of Astr. Soc. The Moon from Transit Observations of (Memoirs) Venus near her inferior conjunction. 1829 Nov. 16 On a Correction requisite to be applied Camb. Phil. Soc. To the Length of a Pendulum consisting of a Ball suspended by a fine Wire. 1829 Dec. 14 On certain Conditions under which a Camb. Phil. Soc. Perpetual Motion is possible. 1830 Aug. 17 Figure of the Earth. Encycl. Metrop. 1831 Feb. 21 On the Nature of the Light in the Two Camb. Phil. Soc. Rays produced by the Double Refraction of Quartz. 1831 Apr. 18 Addition to the above Paper. Camb. Phil. Soc. 1831 Nov. 14 On a remarkable Modification of Newton's Camb. Phil. Soc. Rings. 1831 Nov. 24 On an inequality of long period in the Phil. Trans. Motions of the Earth and Venus. 1832 Jan. 2 Translation of Encke's Dissertation (on Encke's Comet) contained in Nos. 210 and 211 of the Astronomische Nachrichten. 1833 Mar. 5 On a new Analyzer, and its use in Camb. Phil. Soc. Experiments of Polarization. 1832 Mar. 19 On the Phenomena of Newton's Rings when formed between two transparent Substances of different refractive Powers. 1832 May 2 Report on the Progress of Astronomy Trans Brit. Ass. During the present century. 1832 Oct. Report of the Syndicate of the Cambridge Observatory. 1833 Feb. 2 Remarks on Mr Potter's Experiment on Phil. Mag. Interference. 1833 Apr. 12 On the Mass of Jupiter, as determined R. Astr. Soc. From the Observation of Elongations of (Memoirs) the Fourth Satellite. 1833 Syllabus of a Course of Experimental Lectures. 1833 May 7 On the Calculation of Newton's Camb. Phil. Soc. Experiments on Diffraction. 1833 May 7 Remarks on Sir David Brewster's Paper Phil. Mag. "On the Absorption of Specific Rays" &c. 1833 May 16 Results of the Repetition of Mr Potter's Phil. Mag. Experiment of interposing a Prism in the Path of Interfering Light. 1833 May On a supposed black bar formed by Phil. Mag. Diffraction. 1833 June 20 Report on Mr Barlow's Fluid-Lens R. Soc. (Proc. ) Telescope 1834 Mar. 14 Continuation of Researches into the Value R. Astr. Soc. Of the Mass of Jupiter, by observation of (Memoirs. ) the Elongations of the Fourth Satellite. 1834 Apr. 14 On the Latitude of Cambridge Observatory Camb. Phil. Soc. 1834 June Report of the Syndicate of the Cambridge Observatory. 1834 June 13 On the Position of the Ecliptic, as inferred R. Astr. Soc. Inferred from Transit and Circle (Memoirs. ) Observations made at Cambridge Observatory in the year 1833. 1834 June 13 Observations of the Solar Eclipse of July R. Astr. Soc. 16th, 1833, made at Cambridge Observatory, (Memoirs. ) and Calculations of the Observations. 1834 Nov. 24 On the Diffraction of an Object-Glass Camb. Phil. Soc. With Circular Aperture. 1834 Dec. 3 On the Calculation of the Perturbations Naut. Alm. Of the Small Planets and the Comets of (1837, App. ) short period. 1835 May 8 Continuation of Researches into the Value R. Astr, Soc. Of Jupiter's Mass. (Memoirs. ) 1835 June Report of the Syndicate of the Cambridge Observatory. 1835 June 12 On the Position of the Ecliptic, as R. Astr. Soc. Inferred from Observations with the (Memoirs. ) Cambridge Transit and Mural Circle, made in the year 1834. 1835 June 12 On the Time of Rotation of Jupiter. R. Astr. Soc. (Memoirs. ) 1836 Feb. 12 Speech on delivering the Medal of the R. Astr. Soc. R. Astr. Soc. To Sir John Herschel. (Proc. ) 1836 June 4 Report of the Astronomer Royal to the Board of Visitors. 1836 June 9 Report upon a Letter (on a Systematic R. Soc. Course of Magnetic Observations) addressed (Proc. ) by M. Le Baron de Humboldt to His Royal Highness the President of the Royal Society (by S. Hunter Christie and G. B. Airy). 1837 Jan. 13 Continuation of Researches into the Value R. Astr. Soc. Of Jupiter's Mass. (Memoirs. ) 1837 Feb. 10 Speech on delivering the Medal of the R. Astr. Soc. R. Astr. Soc. To Professor Rosenberger. (Proc) 1837 Mar. 10 Results of the Observations of the Sun, R. Astr. Soc. Moon, and Planets, made at Cambridge (Memoirs) Observatory in the years 1833, 1834, and 1835. 1837 May 12 On the Position of the Ecliptic, as R. Astr. Soc. Inferred from Observations with the (Memoirs) Cambridge Transit and Mural Circle, made in the year 1835. 1837 June 3 Report of the Astronomer Royal to the Board of Visitors. 1837 Sept. 9 Address delivered in the Town Hall of Neath. 1837 Nov. 10 On the Parallax of alpha Lyrae. R. Astr. Soc. (Memoirs. ) 1838 Feb. 10 Address to the Earl of Burlington on Religious Examination in the University of London. 1838 Mar. 26 On the Intensity of Light in the Camb. Phil. Soc. Neighbourhood of a Caustic. 1838 June 2 Report of the Astronomer Royal to the Board of Visitors. 1838 Dec. 14 A Catalogue of 726 Stars, deduced from R. Astr. Soc. The Observations made at the Cambridge (Memoirs. ) Observatory, from 1828 to 1835; reduced to January 1, 1830. 1839 Apr. 25 Account of Experiments on Iron-built Phil. Trans. Ships, instituted for the purpose of discovering a correction for the deviation of the Compass produced by the iron of the Ships. 1839 June 1 Report of the Astronomer Royal to the Board of Visitors. 1839 Nov. 8 On the Determination of the Orbits of R. Astr. Soc. Comets, from Observations. (Memoirs. ) 1839 Article "Gravitation. " Penny Cyclop. 1839 Article "Greenwich Observatory. " Penny Cyclop. 1840 Mar. 2 On a New Construction of the Camb. Phil. Soc. Going-Fusee. 1840 Mar. 13 On the Regulator of the Clock-work for R. Astr. Soc. Effecting uniform Movement of Equatoreals. 1840 May 15 On the Correction of the Compass in Un. Serv. Journ. Iron-built Ships. (Proc. ) 1840 Results of Experiments on the Disturbance J. Weale. Of the Compass in Iron-built Ships. 1840 June 6 Report of the Astronomer Royal to the Board of Visitors. 1840 June 18 On the Theoretical Explanation of an Phil. Trans. Apparent new Polarity in Light. 1840 Nov. 19 Supplement to the above Paper. Phil. Trans. 1840 Dec. 4 On the Diffraction of an Annular Aperture. Phil. Mag. 1840 Dec. 9 Remarks on Professor Challis's Investigation Phil. Mag. Of the Motion of a Small Sphere vibrating in a Resisting Medium. 1841 Jan. 20 Correction to the above Paper "On the Phil. Mag. Diffraction, " &c. 1841 Mar. 22 Remarks on Professor Challis's Reply to Phil. Mag. Mr Airy's Objections to the Investigation of the Resistance of the Atmosphere to an Oscillating Sphere. 1841 June 5 Report of the Astronomer Royal to the Board of Visitors. 1841 July 10 Reply to Professor Challis, on the Phil. Mag. Investigation of the Resistance of the Air to an Oscillating Sphere. 1841 Oct. 26 Extraordinary Disturbance of the Magnets. 1841 Nov. 25 On the Laws of the Rise and Fall of the Phil. Trans. Tide in the River Thames. 1841 Dec. 21 Report of the Commissioners appointed to consider the steps to be taken for Restoration of the Standards of Weight and Measure. 1842 Apr. 16 On the [Greek: Ichtis] of Diodorus Athenaeum. 1842 May 13 Account of the Ordnance Zenith Sector. R. Astr. Soc. (Proc. ) 1842 June 4 Report of the Astronomer Royal to the Board of Visitors. 1842 Nov. 11 Observations of the Total Solar Eclipse of R. Astr. Soc. 1842 July 7. (Memoirs. ) 1842 Dec. 1 Remarks on the Present State of Hatcliff's Private Charity (Greenwich). 1842 Article on Tides and Waves. Encyc. Metrop. 1843 Mar. 2 On the Laws of Individual Tides at Phil. Trans. Southampton and at Ipswich. 1843 Apr. 29 On Monetary and Metrical Systems. Athenaeum. 1843 June 3 Report of the Astronomer Royal to the Board of Visitors. 1843 Sept. 25 Address to the Individual Members of the Board of Visitors of the Royal Observatory (proposing the Altazimuth). 1843 Oct. 6 Account of the Northumberland Equatoreal and Dome, attached to the Cambridge Observatory. 1843 Nov. 10 Address and Explanation of the proposed Altitude and Azimuth Instrument to the Board of Visitors of the Royal Observatory. 1844 June 1 Report of the Astronomer Royal to the Board of Visitors. 1844 Dec. 12 On the Laws of the Tides on the Coasts of Phil. Trans. Ireland, as inferred from an extensive series of observations made in connection with the Ordnance Survey of Ireland. 1845 Jan. 10 On the Flexure of a Uniform Bar R. Astr. Soc. Supported by a number of equal Pressures (Memoirs. ) applied at equidistant points, &c. 1845 Feb. 14 Speech on delivering the Medal of the R. Astr. Soc. R. Astr. Soc. To Capt. Smyth (Proc. ) 1845 May 9 On a New Construction of the Divided R. Astr. Soc. Eye-Glass Double-Image Micrometer. (Memoirs. ) 1845 June 7 Report of the Astronomer Royal to the Board of Visitors. 1845 July 21 On Wexford Harbour. 1846 Report of the Gauge Commissioners. And letter to Sir E. Ryan. 1846 May 7 On the Equations applying to Light under Phil. Mag. The action of Magnetism. 1846 May 12 Remarks on Dr Faraday's Paper on Phil. Mag. Ray-vibrations. 1846 May 25 On a Change in the State of an Eye Camb. Phil. Soc. Affected with a Mal-formation. 1846 June 6 Report of the Astronomer Royal to the Board of Visitors. 1846 June Account of the Measurement of an Arc of R. Astr. Soc. Longitude between the Royal Observatory (Month. Not. ) of Greenwich and the Trigonometrical Station of Feagh Main, in the Island of Valentia. 1846 July 25 Letter to Sir Robert Harry Inglis, Bart. , Athenaeum. M. P. , in answer to Sir James South's attack on the Observations at the Greenwich Observatory. 1846 Nov. On the Bands formed by the partial Phil. Mag. Interception of the Prismatic Spectrum. 1846 Nov. 13 Account of some circumstances historically R. Astr. Soc. Connected with the Discovery of the (Memoirs. ) Planet exterior to Uranus. 1847 Jan. 8 Reduction of the Observations of Halley's R. Astr. Soc. Comet made at the Cambridge Observatory in (Memoirs. ) the years 1835 and 1836. 1847 Jan. 8 On a proposed Alteration of Bessel's Method R. Astr. Soc. For the Computation of the Corrections by (Memoirs. ) which the Apparent Places of Stars are derived from the Mean Places. 1847 Feb. On Sir David Brewster's New Analysis of Phil. Mag. Solar Light. 1847 Feb. 20 On the Name of the New Planet. Athenaeum. 1847 Feb. 27 Mr Adams and the New Planet. Athenaeum. 1847 Plan of the Buildings and Grounds of the Royal Observatory, Greenwich, with Explanation and History. 1847 May 14 Explanation of Hansen's Perturbations of R. Astr. Soc. The Moon by Venus. (Month. Not. ) 1847 June 5 Report of the Astronomer Royal to the Board of Visitors. 1847 Nov. 30 Address to the Individual Members of the Board of Visitors of the Royal Observatory. (Zenith Tube. ) 1847 Dec. 10 Results deduced from the Occultations of R. Astr. Soc. Stars and Planets by the Moon, observed (Memoirs. ) at Cambridge Observatory from 1830 to 1835. 1848 Feb. 11 Abstract of Struve's "Études d'Astronomie R. Astr. Soc. Stellaire. " (Month. Not. ) 1848 Mar. 13 Syllabus of Lectures on Astronomy to be delivered at the Temperance Hall, Ipswich. 1848 Apr. 10 Remarks on Prof. Challis's Theoretical Phil. Mag. Determination of the Velocity of Sound 1848 May 8 Supplement to a Paper on the Intensity of Camb. Phil. Soc. Light in the neighbourhood of a Caustic. 1848 May 12 Address to Individual members of the Board of Visitors. (New Transit Circle, Reflex Zenith Tube, &c. ) 1848 June 3 Report of the Astronomer Royal to the Board of Visitors. 1848 June 9 Corrections of the Elements of the Moon's R. Astr. Soc. Orbit, deduced from the Lunar (Memoirs. ) Observations made at the Royal Observatory, of Greenwich from 1750 to 1830. 1848 Aug. 9 Explanation of a proposed construction of Zenith Sector: addressed to the Board of Visitors of the Royal Observatory, Greenwich. 1848 Oct. 14 On the Construction of Chinese Balls Athenaeum. 1849 Description of the Instruments of Process used in the Photographic self-registration of the Magnetical and Meteorological Instruments at the Royal Observatory, Greenwich. 1849 Description of the Altitude and Azimuth Instrument erected at the Royal Observatory, Greenwich, in the year 1847. 1849 Astronomy. (Tract written for the Scientific Manual. ) 1849 Mar. 9 Substance of the Lecture delivered by the R. Astr. Soc. Astronomer Royal on the large Reflecting (Month. Not. ) Telescopes of the Earl of Rosse and Mr Lassell. 1849 June On a difficulty in the problem of Sound. Phil. Mag. 1849 June 2 Report of the Astronomer Royal to the Board of Visitors. 1849 June 8 On Instruments adapted to the Measure of R. Astr. Soc. Small Meridional Zenith Distances. (Month. Not. ) 1849 Nov. 9 Results of the Observations made by the R. Astr. Soc. Rev. Fearon Fallows at the Royal (Memoirs. ) Observatory, Cape of Good Hope, in the years 1829, 1830, 1831. 1849 Nov. 9 On Bell's Calculating machine, and on R. Astr. Soc. Lord Rosse's Telescope. (Month. Not. ) 1849 Nov. 10 On the Exodus of the Israelites. Athenaeum. 1849 Dec. 14 On the Method of observing and recording R. Astr. Soc. Transits, lately introduced in America, &c. (Month. Not. ) 1850 Jan. 10 On a problem of Geodesy. Phil. Mag. 1850 Feb. 8 Address on presenting the Medal of the R. Astr. Soc. R. Astr. Soc. To M. Otto von Struve. (Month. Not. ) 1850 Mar. 15 On the Present State and Prospects of the R. Inst. Science of Terrestrial Magnetism. 1850 Mar. 16 On the Exodus of the Israelites Athenaeum. 1850 Mar. 30 On the Exodus of the Israelites. Athenaeum. 1850 May 10 Statement concerning Assistance granted R. Astr. Soc. By the Admiralty to Hansen--Also on (Month. Not. ) Henderson's numbers for the teeth of wheels. 1850 May 10 On the Weights to be given to the separate R. Astr. Soc. Results for Terrestrial Longitudes, (Memoirs. ) determined by the observation of Transits of the Moon and Fixed Stars. 1850 June 1 Report of the Astronomer Royal to the Board of Visitors. 1850 June 14 Letter from Hansen on his Lunar Tables. --Valz R. Astr. Soc. On an arrangement of double-image (Month. Not. ) micrometer. --On the Computation of Longitude from Lunar Transits 1850 Dec. 13 On a Method of regulating the Clock-work R. Astr. Soc. For Equatoreals. (Month. Not. ) 1850 Dec. 13 Supplement to a Paper "On the Regulation R. Astr. Soc. Of the Clock-work for effecting Uniform (Memoirs. ) Movement of Equatoreals. " 1850 Dec. 27 On the Relation of the Direction of the Phil. Trans. Wind to the Age of the Moon, as inferred from Observations made at the Royal Observatory, Greenwich, from 1840 Nov. To 1847 Dec. 1851 Jan. 14 Remarks on Mr Wyatt's Paper on the Inst. C. E. Construction of the Building for the (Minutes. ) Exhibition of the Works of Industry of all Nations in 1851. 1851 Feb. 15 Address on presenting the medal of the R. Astr. Soc. R. Astr. Soc. To Dr Annibale de (Month. Not. ) Gasparis. 1851 Mar. 28 Letter to Professor Challis regarding the Adams Prize. 1851 Mar. 29 On Caesar's place of landing in Britain. Athenaeum. 1851 Suggestions to Astronomers for the Brit. Assoc. Observation of the Total Eclipse of the Sun on July 28, 1851. 1851 Apr. 11 On the Determination of the probable R. Astr. Soc. Stability of an Azimuthal Circle by (Month. Not. ) Observations of Star and a permanent Collimator. 1851 May 2 On the Total Solar Eclipse of 1851, July 28. R. Inst. (Lecture. ) 1851 May 9 On the Vibration of a Free Pendulum in an R. Astr. Soc. Oval differing little from a Straight Line (Memoirs) 1851 June 7 Report of the Astronomer Royal to the Board of Visitors. 1851 July 2 The President's Address to the Twenty-first Athenaeum. Meeting of the British Association for the Advancement of Science, Ipswich. 1851 Oct. 17 On Julius Caesar's Expedition against Naut. Mag. England, in relation to his places of departure and landing. 1851 Nov. 14 Account of the Total Eclipse of the Sun on R. Astr. Soc. 1851, July 28, as observed at Göttenburg, (Memoirs. ) at Christiania, and at Christianstadt. 1851 Dec. 13 On the Geography of the Exodus. Athenaeum. 1852 Jan. 9 On the Solar Eclipse of July 28, 1851. R. Astr. Soc. (Month. Not. ) 1852 On the place of Caesar's Departure from Soc. Of Antiq. Gaul for the Invasion of Britain, and (Memoirs. ) the Place of his Landing in Britain, with an Appendix on the Battle of Hastings. 1852 On a New Method of computing the Naut. Alm. 1856, Perturbations of planets, by J. F. App. Encke--translated and illustrated with notes by G. B. Airy. 1852 June 5 Report of the Astronomer Royal to the Board of Visitors. 1853 Feb. 3 On the Eclipses of Agathocles, Thales, Phil. Trans. And Xerxes. 1853 Feb. 4 Lecture on the results of recent R. Inst. Calculations on the Eclipse of Thales and Eclipses connected with it. 1853 May 3 Address to the Individual Members of the Board of Visitors of the Royal Observatory, Greenwich. (Lunar Reductions. ) 1853 May 14 On Decimal Coinage. Athenaeum. 1853 June 4 Report of the Astronomer Royal to the Board of Visitors. 1853 June Lecture on the Determination of the R. Astr. Soc. Longitude of the Observatory of (Month. Not. ) Cambridge by means of Galvanic Signals. 1853 Sept. 10 On Decimal Coinage. Athenaeum. 1853 Dec. 14 Description of the Transit Circle of the Royal Observatory, Greenwich. (App. Gr. Observ. 1852. ) 1853 Dec. 14 Regulations of the Royal Observatory, Greenwich. (App. Gr. Observ. 1852. ) 1854 Jan. 14 On the Telegraphic Longitude of Brussels. Athenaeum. 1854 Feb. 10 Address on presenting the Gold Medal of R. Astr. Soc. The R. Astr. Soc. To Mr Charles Rümker. (Month. Not. ) 1854 Feb. 25 On Reforms in the University of Cambridge. Athenaeum. 1854 Apr. 15 Letters relating to "The Late M. Mauvais. " Liter. Gaz. 1854 June 3 Report of the Astronomer Royal to the Board of Visitors. 1854 Sept. The Deluge. Private. 1854 Oct. 28 On the Correction of the Compass in Iron Athenaeum. Ships. (Scoresby's Experiments. ) 1854 Nov. 10 On the Difference of Longitude between R. Astr. Soc. The Observatories of Brussels and Greenwich, (Memoirs. ) as determined by Galvanic Signals. 1855 Jan. 1 Lecture at S. Shields on the Pendulum Experiments in the Harton Pit, and Letter on the Results. 1855 Feb. 2 Lecture on the Pendulum Experiments R. Inst. Lately made in the Harton Colliery for ascertaining the mean Density of the Earth. 1855 Feb. 3 On the Correction of the Compass in Iron Athenaeum. Ships. (Remarks on Dr Scoresby's Investigations. ) 1855 Address on presenting the Medal of the R. Astr. Soc. R. Astr. Soc. To the Rev. William Rutter (Month. Not. ) Dawes. 1855 Feb. 15 On the Computation of the Effect of the Phil. Trans. Attraction of Mountain Masses, as disturbing the Apparent Astronomical Latitude of Stations in Geodetic Surveys. 1855 June 2 Report of the Astronomer Royal to the Board of Visitors. 1855 Oct. 18 Address to the Individual Members of the Board of Visitors of the Royal Observatory, Greenwich. (Equatoreal. ) 1855 Nov. 21 Remarks upon certain Cases of Personal R. Astr. Soc. Equation which appear to have hitherto (Memoirs. ) escaped notice, accompanied with a Table of Results. 1855 Nov. 22 Discussion of the Observed Deviations of Phil. Trans. The Compass in several Ships, Wood-built and Iron-built: with a General Table for facilitating the examination of Compass-Deviations. 1855 Description of the Reflex Zenith Tube of the Royal Observatory, Greenwich. (App. To the Greenwich Obs. For 1854. ) 1856 Jan. 9 On Professor Peirce's Criterion for Astr. Journ. Discordant observations. (Cambr. ) 1856 Jan. 24 Account of Pendulum Experiments undertaken Phil. Trans. In the Harton Colliery, for the purpose of determining the Mean Density of the Earth. 1856 June 7 Report of the Astronomer Royal to the Board of Visitors. 1856 Aug. 25 On Scheutz's Calculating Machine. Phil. Mag. 1856 Aug. 30 Science and the Government. (Reply to Athenaeum. Statements in the Morning Chronicle about the instrumental equipment of the Royal Observatory. ) 1857 May 8 On the Means which will be available for R. Astr. Soc. Correcting the Measure of the Sun's (Month. Not. ) Distance in the next twenty-five years. 1857 May 12 Knowledge expected in Computers and Assistants in the Royal Observatory. 1857 June 6 Report of the Astronomer Royal to the Board of Visitors. 1857 June 12 On the Eclipse of Agathocles, the Eclipse R. Astr. Soc. At Larissa, and the Eclipse of Thales. (Memoirs. ) With an Appendix on the Eclipse of Stiklastad. 1857 June 18 Account of the Construction of the New Phil. Trans. National Standard of Length, and of its principal copies. 1857 Dec. 5 Letter to the Vice-Chancellor of Cambridge University regarding Smith's Prizes. 1857 Dec. 7 On the Substitution of Methods founded Camb. Phil. Soc. On Ordinary Geometry for Methods based on the General Doctrine of Proportions, in the treatment of some Geometrical Problems 1857 Description of the Galvanic Chronographic Gr. Obs. 1856, Apparatus of the Royal Observatory, App. Greenwich. 1858 Mar. 8 Suggestions for Observation of the Annular Eclipse of the Sun on 1858, March 14-15. 1858 Mar. 12 Note on Oltmann's Calculation of the R. Astr. Soc. Eclipse of Thales. Also On a Method (Month. Not. ) of very approximately representing the Projection of a Great Circle upon Mercator's Chart. 1858 May The Atlantic Cable Problem. Naut. Mag. 1858 May 20 Report of the Ordnance Survey Commission; together with Minutes of Evidence and Appendix. 1858 June 5 Report of the Astronomer Royal to the Board of Visitors. 1858 June 16 On the Mechanical Conditions of the Phil. Mag. Deposit of a Submarine Cable. 1858 July Instructions and Chart for Observations R. Astr. Soc. Of Mars in right ascension at the (Special. ) Opposition of 1860 for obtaining the Measure of the Sun's Distance. 1858 Aug. 20 On the Advantageous Employment of Photog. Notes. Stereoscopic Photographs for the representation of Scenery. 1858 Nov. 6 On the "Draft of Proposed New Statutes Athenaeum. For Trinity College, Cambridge. " 1858 Nov. 20 Letter to the Vice-Chancellor of the University of Cambridge, offering the Sheepshanks Endowment. 1858 Dec. 6 Suggestion of a Proof of the Theorem Camb. Phil. Soc. That Every Algebraic Equation has a Root. 1859 Manual of Astronomy--for the Admiralty. Parly. Paper. 1859 Feb. 1 Letter to Lord Monteagle relating to the Standards of Weights and Measures. 1859 Feb. 4 Remarks on Mr Cayley's Trigonometrical Phil. Mag. Theorem, and on Prof. Challis's Proof that Equations have Roots. 1859 Mar. 11 On the Movement of the Solar System in R. Astr. Soc. Space. (Memoirs. ) 1859 Apr. 8 On the Apparent Projection of Stars upon R. Astr. Soc. The Moon's Disc in Occultations. Also (Month. Not. ) Comparison of the Lunar Tables of Burckhardt and Hansen with Observations of the Moon made at the Royal Observatory, Greenwich. 1859 Apr. 8 On the Apparent Projection of Stars upon R. Astr. Soc. The Moon's Disc in Occultations. (Memoirs. ) 1859 June 4 Report of the Astronomer Royal to the Board of Visitors. 1859 June 10 Abstract of Maxwell's Paper "On the R. Astr. Soc. Stability of the Motion of Saturn's Rings. " (Month. Not. ) 1859 July 8 Corrections of the Elements of the Moon's R. Astr. Soc. Orbit, deduced from the Lunar Observations (Memoirs. ) made at the Royal Observatory of Greenwich from 1750 to 1851. 1859 Sept. 10 On the Invasion of Britain by Julius Caesar. Athenaeum. (Answer to Mr Lewin. ) 1859 Nov. 12 On Iron Ships--The Royal Charter. Athenaeum. (Answer to Archibald Smith's Remarks. ) 1859 Nov. Circular requesting observations of small Planets. 1859 Dec. 9 Notice of the approaching Total Eclipse of R. Astr. Soc. The Sun of July 18, 1860, and suggestions (Month. Not. ) for observation. 1859 Dec. 12 Supplement to A Proof of the Theorem Camb. Phil. Soc. That Every Algebraic Equation has a Root. 1860 Jan. 13 Description of the New Equatoreal at the R. Astr. Soc. Royal Observatory, Greenwich. Also (Month. Not. ) Abstract of an Essay by Gen. T. F. De Schubert on the Figure of the Earth. 1860 Jan. 28 On the Claudian or Plautian Invasion of Athenaeum Britain. 1860 Feb. 2 Examination of Navy 2-foot Telescopes at the Royal Observatory, Greenwich, 1860, Jan. 31 to Feb. 2. 1860 Feb. 11 Report on the Instrumental Equipments Ho. Of Commons. Of the Exchequer Office of Weights and (Parly. Paper. ) Measures, as regards the means for preventing Fraud in the Sale of Gas to the Public; and on the Amendments which may be required to the existing Legislation on that subject. 1860 Mar. 9 Address on the approaching Solar Eclipse R. Astr. Soc. Of July 18, 1860, &c. (Month. Not. ) 1860 May 10 Correspondence between the Lords Ho. Of Commons. Commissioners of Her Majesty's Treasury, (Parly. Paper. ) &c. , and the Astronomer Royal, relating to Gas Measurement, and the Sale of Gas Act. 1860 June 2 Report of the Astronomer Royal to the Board of Visitors. And Address to the Members of the Board in reference to Struve's Geodetic suggestions. 1860 June 7 Correspondence regarding the Grant of _£1000_ to Prof. Hansen for his Lunar Tables. 1860 Sept. 13 Remarks on a Paper entitled "On the Polar Distances of the Greenwich Transit Circle, by A. Marth. " Addressed to the Members of the Board of Visitors. 1860 Sept. 22 On Change of Climate, in answer to Athenaeum. Certain speculations by Sir Henry James. 1860 Oct. 20 Circular relating to the distribution of Greenwich Observations and other publications of the Royal Observatory. 1860 Nov. 9 Account of Observations of the Total R. Astr. Soc. Solar Eclipse of 1860, July 18, made (Month. Not. ) at Hereña, near Miranda de Ebro; &c. &c. 1860 Nov. 17 On Change of Climate: further discussion. Athenaeum. 1860 Letters on Lighthouses, to the Commission on Lighthouses. 1860 Dec. 14 Note on the translation of a passage in a R. Astr. Soc. Letter of Hansen's relating to (Month. Not. ) coefficients. 1861 Feb. 9 On the Temperature-correction of Syphon Athenaeum. Barometers. 1861 March Results of Observations of the Solar R. Astr. Soc. Eclipse of 1860 July 18 made at the Royal (Month. Not. ) Observatory, Greenwich, for determination of the Errors of the Tabular Elements of the Eclipse. Also Suggestion of a new Astronomical Instrument, for which the name "Orbit-Sweeper" is proposed. Also Theory of the Regulation of a Clock by Galvanic Currents acting on the Pendulum. 1861 June 1 Report of the Astronomer Royal to the Board of Visitors. 1861 June 5 On a supposed Failure of the Calculus of Phil. Mag. Variations. 1861 July Report of a Committee of the R. Soc. On R. Soc. (Proc. ) the advisability of re-measuring the Indian Arc of Meridian. 1861 Sept. 21 Lecture at Manchester on the Great Solar Athenaeum. Eclipse of July 18, 1860. 1861 Sept. 21 The same Lecture. London Review. 1861 Oct. Examination Paper for the Sheepshanks Exhibition. 1861 Nov. 1 Translation of Dr Lamont's Paper "On the Phil. Mag. Most Advantageous Form of Magnets. " 1861 Nov. 8 Note on a Letter received from Hansen on R. Astr. Soc. The Lunar Theory. Also Discussion of (Month. Not. ) a Result deduced by Mr D'Abbadie from Observations of the Total Solar Eclipse of 1860, July 18. 1861 Nov. 16 Instructions for observing the Total Eclipse of the Sun on December 31. 1861 Dec. On a Projection by Balance of Errors for Phil. Mag. Maps. 1861 Dec. 28 On the Circularity of the Sun's Disk. R. Astr. Soc. Also Table of Comparative Number of (Month. Not. ) Observations of Small Planets. 1862 Jan. On the Direction of the Joints in the Phil. Mag. Faces of Oblique Arches. 1862 Mar. 15 Review of "An Historical Survey of the Athenaeum. Astronomy of the Ancients" by the Rt Hon. Sir G. Cornewall Lewis. 1862 Apr. 24 Notes for the Committee on Weights and Measures, 1862. 1862 May 15 On the Magnetic Properties of Hot-Rolled Phil. Trans. And Cold-Rolled Malleable Iron. 1862 June 7 Report of the Astronomer Royal to the Board of Visitors. 1862 June 24 Evidence given before the Select Committee on Weights and Measures. 1862 Oct. 4 Biography of G. B. Airy (probably in part London Review. Based upon data supplied by himself). 1862 Oct. 11 Abstract of Paper "On the Strains in the Athenaeum. Interior of Beams and Tubular Bridges. " 1862 Oct. 11 Translation of a Letter from Prof. Lament Phil. Mag. On Dalton's Theory of Vapour, &c. 1862 Nov. 6 On the Strains in the Interior of Beams. Phil. Trans. 1862 Nov. Correspondence with Sabine concerning his attack on the Greenwich Magnetic Observations. (Confidentially communicated to the Board of Visitors. ) 1862 Nov. 21 Evidence given before the Public Schools Commission. 1862 Nov. Abstract of M. Auwers's Paper on the R. Astr. Soc. Proper motion of Procyon, and Note on (Month. Not. ) same. 1862 Dec. Abstract of Mr Safford's Paper on the R. Astr. Soc. Proper Motion of Sirius. Also on the (Month. Not. ) Forms of Lenses proper for the Negative Eye-pieces of Telescopes. Also on the measurements of the Earth, and the dimensions of the Solar System. Also on Fringes of Light in Solar Eclipses. 1863 Jan. Address to the Board of Visitors on a further attack by Sabine on the Greenwich Magnetic Observations (confidential). 1863 Jan. 9 On the Observations of Saturn made at R. Astr. Soc. Pulkowa and Greenwich. (Month. Not. ) 1863 Feb. 24 Report to the Board of Trade on the Proposed Lines of Railway through Greenwich Park. 1863 Mar. 2 Determination of the Longitude of Valencia in Ireland by Galvanic Signals in the summer of 1862 (App. III. To the Gr. Astr. Obsns. 1862). 1863 Mar. 13 On the Movement of the Solar System in R. Astr. Soc. Space, deduced from the Proper Motions (Memoirs. ) of 1167 Stars. By Edwin Dunkin (for G. B. A. ). 1863 Mar. 13 On the Visibility of Stars in the Pleiades R. Astr. Soc. To the unarmed eye. (Month. Not. ) 1863 Mar. 21 On Marriage Odes. Athenaeum. 1863 Apr. 9 Further Report as to the Probable Effects of the London, Chatham and Dover Railway on the Royal Observatory in Greenwich Park. 1863 Apr. 10 Determination of the Sun's Parallax from R. Astr. Soc. Observations of Mars during the (Month. Not. ) Opposition of 1862. By E. J. Stone (for G. B. A. ). Also Remarks on Struve's account of a Local deviation in the direction of Gravity, near Moscow. Also an Account of an apparatus for the observation of the spectra of stars, and results obtained. 1863 Apr. 23 On the Diurnal Inequalities of Phil. Trans. Terrestrial Magnetism, as deduced from observations made at the Royal Observatory, Greenwich, from 1841 to 1857. 1863 May 8 On the Discordance between the Results R. Astr. Soc. For Zenith-Distances obtained by Direct (Memoirs. ) Observation, and those obtained by Observation by Reflection from the Surface of Quicksilver. 1863 June 6 Report of the Astronomer Royal to the Board of Visitors. 1863 July 2 On the Amount of Light given by the R. Astr. Soc. Moon at the greatest stage in the (Month. Not. ) Excentrically-total Eclipse, 1863, June 1. 1863 Aug. Plan of the Buildings and Grounds of the Royal Observatory, Greenwich, with Explanation and History. 1863 Sept. 5 On the origin of the apparent luminous R. Astr. Soc. Band which, in partial eclipses of the (Month. Not. ) Sun, has been seen to surround the visible portion of the Moon's limb. 1863 Sept. 5 On the Invasions of Britain by Julius Athenaeum. 1863 Oct. 3 Caesar. 1863 Oct. 17 The Earthquake as observed from Greenwich. Athenaeum. 1863 Nov. On the Numerical Expression of the Phil. Mag. Destructive Energy in the Explosions of Steam-Boilers, &c. 1863 Nov. 13 Convention arranged between M. Le Verrier R. Astr. Soc. And the Astronomer Royal for meridional (Month. Not. ) observations of the small Planets, &c. 1863 Nov. 13 Translation of Hansen's Paper R. Astr. Soc. "Calculation of the Sun's Parallax (Month. Not. ) from the Lunar Theory, " with Notes by G. B. A. 1863 Dec. 17 First Analysis of 177 Magnetic Storms, Phil. Trans. Registered by the Magnetic Instruments in the Royal Observatory, Greenwich, from 1841 to 1857. 1864 Jan. 8 Pontécoulant's Paper "Sur le Coefficiant R. Astr. Soc. De l'Équation Parallactique déduit de la (Month. Not. ) Théorie, " with Notes by G. B. A. 1864 Jan. 26 Remarks on Redman's Paper on the East Inst. C. E. Coast (Chesil Bank, &c. ). (Minutes. ) 1864 Mar. 10 Note on a Passage in Capt. R. Astr. Soc. Jacob's "Measures of Jupiter, " &c. (Month. Not. ) 1864 Mar. 11 Notes for the Committee on Weights and Ho. Of Comm. Measures, 1862. (Parly. Paper. ) 1864 Mar. 17 On a Method of Slewing a Ship without Inst. Nav. Arch. The aid of the Rudder. 1864 Apr. 5 Comparison of the Chinese Record of Solar R. Astr. Soc. Eclipses in the Chun Tsew with the (Month. Not. ) Computations of Modern Theory. 1864 June 4 Report of the Astronomer Royal to the Board of Visitors. 1864 June 10 On the Transit of Venus, 1882, Dec. 6. R. Astr. Soc. (Month. Not. ) 1864 June 10 On the bright band bordering the Moon's R. Astr. Soc. Limb in Photographs of Eclipses. (Month. Not. ) 1864 Notes on Methods of Reduction applicable to the Indian Survey. 1864 Sept. 3 A Visit to the Corryvreckan. Athenaeum. 1864 Sept. 29 Examination Paper for the Sheepshanks Scholarship. 1865 Jan. 13 Comparison of the Transit-Instrument in R. Astr. Soc. Its ordinary or reversible form with the (Month. Not. ) Transit-Instrument in its non-reversible form, as adopted at Greenwich, the Cape of Good Hope, and other Observatories. 1865 Mar. 9 Syllabus of a course of three Lectures on "Magnetical Errors, &c. , with special reference to Iron Ships and their Compasses, " delivered at the South Kensington Museum. 1865 Apr. 1 Remarks on Mr Ellis's Lecture on the Horolog. Journ. Greenwich System of Time Signals. 1865 Apr. 1 Free Translation of some lines of Virgil, Athenaeum. "Citharâ crinitus Iopas, " &c. 1865 June 3 Report of the Astronomer Royal to the Board of Visitors. 1865 June 17 Note on my Recommendation (in 1839) Athenaeum. Of Government Superintendence of the Compasses of Iron Ships. Also Note on the birthplace of Thomas Clarkson. 1865 July On Hemiopsy. Phil. Mag. 1865 Aug. 22 On the Value of the Moon's Semidiameter R. Astr. Soc. As obtained by the Investigations of (Month. Not. ) Hugh Breen, Esq. , from Occultations observed at Cambridge and Greenwich. 1865 Sept. 16 On "The Land of Goshen"--Reply to "A Athenaeum. Suffolk Incumbent. " 1865 Oct. 21 Address of the Astronomer Royal to the individual members of the Board of Visitors. (On improved Collimators. ) 1865 Oct. 23 Note on an Error of Expression in two R. Astr. Soc. Previous Memoirs. Also Description and (Month. Not. ) History of a Quadrant made by Abraham Sharp. 1865 Nov. 11 On the Possible Derivation of the National Athenaeum. Name "Welsh. " 1865 Essays on the Invasion of Britain by Julius Private. Caesar; The Invasion of Britain by Plautius, and by Claudius Caesar; The Early Military Policy of the Romans in Britain; The Battle of Hastings. (With corr. ) 1866 Mar. 10 On "The Compass in Iron Ships. " Objections Athenaeum. To passages in a Lecture by Archibald Smith. 1866 Apr. 13 On the Supposed Possible Effect of R. Astr. Soc. Friction in the Tides, in influencing the (Month. Not. ) Apparent Acceleration of the Moon's Mean Motion in Longitude. Also on a Method of Computing Interpolations to the Second Order without Changes of Algebraic Sign. 1866 June 2 Report of the Astronomer Royal to the Board of Visitors. 1866 July 17 Papers relating to Time Signals on the Ho. Of Comm. Start Point. (Parly. Paper. ) 1866 Sept. 1 On the Campaign of Aulus Plautius in Athenaeum. Britain. (Reply to Dr Guest. ) 1866 Nov. 19 On the Continued Change in an Eye Camb. Phil. Soc. Affected with a peculiar malformation. 1866 Dec. On the Simultaneous Disappearance of R. Astr. Soc. Jupiter's Satellites in the year 1867. (Month. Not. ) Also Inference from the observed Movement of the Meteors in the appearance of 1866, Nov. 13-14. 1867 Jan. 1 Memorandum for the consideration of the Commission on Standards. (Policy of introducing Metrical Standards. ) 1867 Jan. 12 On Decimal Weights and Measures. Athenaeum. 1867 Feb. 19 On the use of the Suspension Bridge with Inst. C. E. Stiffened Roadway for Railway and other (Minutes. ) Bridges of Great Span. 1867 Mar. 21 Computation of the Lengths of the Waves Phil. Trans. Of Light corresponding to the Lines in the Dispersion Spectrum measured by Kirchhoff. 1867 Mar. Corresponding Numbers of Elevation in R. Obs. (Also English Feet, and of Readings of Aneroid Meteor. Soc. Or Corrected Barometer in English Apr. 17, 1867. ) Inches. 1867 Apr. 16 Remarks on Sir W. Denison's Paper on Inst. C. E. "The Suez Canal. " (Minutes. ) 1867 May 3 Statement of the History and Position of Private. The Blue-coat Girls' School, Greenwich. 1867 June 1 Report of the Astronomer Royal to the Board of Visitors. 1867 June 14 On Certain Appearances of the Telescopic R. Astr. Soc. Images of Stars described by the Rev. (Month. Not. ) W. R. Dawes. 1867 Dec. 13 Note on the Total Solar Eclipse of 1868, R. Astr. Soc. Aug. 17-18. (Month. Not. ) 1868 Biography of G. B. Airy. (Probably corrected by himself. ) 1868 Jan. 4 Biography (with portrait) of G. B. Airy. Ill. Lond. News. (Probably corrected by himself. ) 1868 Feb. 6 Comparison of Magnetic Disturbances Phil. Trans. Recorded by the Self-registering Magnetometers at the Royal Observatory, Greenwich, with Magnetic Disturbances deduced from the corresponding Terrestrial Galvanic Currents recorded by the Self-registering Galvanometers of the Royal Observatory. 1868 Mar. 13 Address of the Astronomer Royal to the Individual Members of the Board of Visitors. (Number of Copies of Observations. ) 1868 June 6 Report of the Astronomer Royal to the Board of Visitors. 1868 July 24 First Report of the Commissioners appointed Parly. Paper. To enquire into The Condition of the Exchequer Standards. 1868 Sept. 19 The Inundation at Visp. Athenaeum. 1868 Nov. 9 On the Factorial Resolution of the Trinomial Camb. Phil. Soc. X^n - 2cos n. A. + 1/x^n. 1868 Dec. 10 On the Diurnal and Annual Inequalities Phil. Trans. Of Terrestrial Magnetism, as deduced from Observations made at the Royal Observatory from 1858 to 1863, &c. 1868 Dec. 11 On the Preparatory Arrangements for the R. Astr. Soc. Observation of The Transits of Venus (Month. Not. ) 1874 and 1882. 1868 Dec. 12 On the Migrations of the Welsh Nations. Athenaeum. 1869 Mar. 8 Memorandum by the Chairman (on the use of the Troy Weight) for the consideration of the Members of the Standards Commission. 1869 Apr. 3 Second Report of the Commissioners appointed Parly. Paper. To enquire into the condition of the Exchequer (now Board of Trade) Standards. --The Metric System. 1869 April Syllabus of Lectures on Magnetism to be delivered in the University of Cambridge. 1869 Apr. 27 Remarks on Shelford's Paper "On the Inst. C. E. Outfall of the River Humber. " (Minutes. ) 1869 June 1 Memorandum for the consideration of the Standards Commission, on the state of the Question now before them regarding the suggested Abolition of Troy Weight. 1869 June 5 Report of the Astronomer Royal to the Board of Visitors. 1869 Supplementary Memorandum by the Astronomer Royal on the proposed Abolition of Troy Weight. 1869 July 6 Correspondence between the Treasury, the Ho. Of Comm. Admiralty, and the Astronomer Royal, (Parly. Paper. ) respecting the arrangements to be made for Observing the Transits of Venus, which will take place in the years 1874 and 1882. 1869 Aug. 7 Note on Atmospheric Chromatic Dispersion R. Astr. Soc. As affecting Telescopic Observation, and (Month. Not. ) on the Mode of Correcting it. 1869 Oct. 19 Description of the Great Equatoreal of the Royal Observatory, Greenwich. Greenwich Observations, 1868. App. 1870 Feb. 3 Note on an Extension of the Comparison Phil. Trans. Of Magnetic Disturbances with Magnetic Effects inferred from observed Terrestrial Galvanic Currents; &c. &c. 1870 Apr. 8 On the question of a Royal Commission Journ. Soc. Arts. For Science. 1870 May 2 Letters to the First Lord of the Admiralty enclosing Application of the Assistants for an increase of Salaries. 1870 May 13 On Decimal and Metrical Systems. Journ. Soc. Arts. 1870 June 4 Report of the Astronomer Royal to the Board of Visitors. 1870 Aug. 27 On the meaning of the word "Whippultree. " Athenaeum. 1870 Oct. 22 On the Locality of "Paradise. " Athenaeum. 1870 Nov. 12 On the Locality of the Roman Gesoriacum. Athenaeum. 1870 Nov. 30 Recommendation of Prof. Miller for a R. Soc. (Proc. ) Royal Medal of the Royal Society. (Quoted by the President. ) 1870 Revised Edition of "Astronomy. " Man. Naut. Sci. 1871 Jan. 21 The Burial of Sir John Moore. Athenaeum. 1871 Mar. 14 Letter to the Hydrographer of the Admiralty on the qualifications and claims of the Assistants of the Royal Observatory. 1871 Apr. 5 Remarks on the Determination of a Ship's R. Soc. (Proc. ) Place at Sea. 1871 May 2 Remarks on Samuelson's Paper "Description Inst. C. E. Of two Blast Furnaces, " &c. (Minutes. ) 1871 May 3 Note on Barometric Compensation of the Phil. Mag. Pendulum. 1871 June 3 Report of the Astronomer Royal to the Board of Visitors. 1871 June 9 Remarks on Mr Abbott's observations on R. Astr. Soc. Eta Argûs. Also on A. S. Herschel's and (Month. Not. ) J. Herschel's Mechanism for measuring Time automatically in taking Transits. 1871 Erratum in Results of Greenwich R. Astr. Soc. Observations of the Solar Eclipse of 1860, (Month. Not. ) July 18. Also Observations of the Solar Eclipse of 1870, Dec. 21-22, made at the Royal Observatory, Greenwich. 1871 Aug. Investigation of the Law of the Progress Phil. Mag. Of Accuracy in the usual process for Forming a Plane Surface. 1871 Nov. 16 Corrections to the Computed Lengths of Phil. Trans. Waves of Light for Kirchhoff's Spectral Lines. 1871 On a supposed alteration in the amount R. Soc. (Proc. ) of Astronomical Aberration of Light, produced by the passage of the Light through a considerable thickness of Refracting Medium. 1871 Nov. 29 Biography of G. B. Airy. (Probably Daily Telegraph. Corrected by himself. ) 1871 Dec. 8 Note on a special point in the R. Astr. Soc. Determination of the Elements of the (Month. Not. ) Moon's Orbit from Meridional Observations of the Moon. 1871 Dec. 26 Proposed devotion of an Observatory to R. Astr. Soc. Observation of the phenomena of Jupiter's (Month. Not. ) Satellites. 1872 Jan. Address to the Council of the Royal Society on the propriety of continuing the Grant to the Kew Observatory for meteorological observations. 1872 Feb. 8 Experiments on the Directive Power of Phil. Trans. Large Steel Magnets, of Bars of magnetized Soft Iron, and of Galvanic Coils, in their Action on external small Magnets--with Appendix by James Stuart. 1872 Feb. 12 Further Observations on the state of an Camb. Phil. Soc. Eye affected with a peculiar malformation. 1872 Mar. 20 Notes on Scientific Education, submitted to the Royal Commission on Scientific Instruction and the Advancement of Science. 1872 May 9 On a Supposed Periodicity in the R. Soc. (Proc. ) Elements of Terrestrial Magnetism, with a period of 26-1/4 days. 1872 Nov. 30 Address (as President) delivered at the Anniversary Meeting of the Royal Society. 1872 Dec. 19 Magnetical Observations in the Phil. Trans. Britannia and Conway Tubular Iron Bridges. 1873 Feb. 25 Remarks on Mr Thornton's Paper on Inst. C. E. "The State Railways of (Minutes. ) India"--chiefly in reference to the proposed break of gauge. 1873 Mar. 12 Note on the want of Observations of R. Astr. Soc. Eclipses of Jupiter's First Satellite (Month. Not. ) from 1868 to 1872. 1873 Mar. 14 Letter to the Secretary of the R. Astr. Soc. Admiralty on certain Articles which (Month. Not. ) had appeared in the Public Newspapers in regard to the approaching Transit of Venus. 1873 Additional Note to the Paper on a R. Soc. (Proc. ) supposed Alteration in the Amount of Astronomical Aberration of Light produced by the passage of the Light through a considerable thickness of Refracting Medium. 1873 Apr. 10 List of Candidates for election into the Royal Society--classified. 1873 On the Topography of the "Lady of Private. The Lake. " 1873 June 7 Report of the Astronomer Royal to the Board of Visitors. 1873 Nov. 14 On the rejection, in the Lunar R. Astr. Soc. Theory, of the term of Longitude (Month. Not. ) depending for argument on eight times the mean longitude of Venus minus thirteen times the mean longitude of the Earth, introduced by Prof. Hansen; &c. 1873 Dec. 1 Address (as President) delivered at the Anniversary Meeting of the Royal Society. 1874 Jan. On a Proposed New Method of treating R. Astr. Soc. The Lunar Theory. (Month. Not. ) 1874 May 4 British Expeditions for the Observation of the Transit of Venus, 1874, December 8. Instructions to Observers. 1874 June 6 Report of the Astronomer Royal to the Board of Visitors. 1874 Aug. 6 Regulations of the Royal Observatory, Greenwich. Appendix to the Greenwich Observations, 1873. 1874 Oct. 3 Science and Art. The Moon as carved Athenaeum. On Lee church. 1874 Nov. 13 Preparations for the Observation of the R. Astr. Soc. Transit of Venus 1874, December 8-9. (Month. Not. ) 1874 Nov. 17 Remarks on the Paper "On the Nagpur Inst. C. E. Waterworks. " (Minutes. ) 1874 Dec. Telegrams relating to the Observations R. Astr. Soc. Of the Transit of Venus 1874, Dec. 9. (Month. Not. ) 1875 Feb. 2 Remarks on Mr Prestwich's Paper on the Inst. C. E. Origin of the Chesil Bank. (Minutes. ) 1875 Feb 25 Letter to the Rev. N. M. Ferrers, on the subject of the Smith's Prizes. 1875 Mar. 12 On the Method to be used in Reducing R. Astr. Soc. The Observations of the Transit of (Month. Not. ) Venus 1874, Dec. 8. 1875 Mar. Report on the Progress made in the R. Astr. Soc. Calculations for a New Method of (Month. Not. ) treating the Lunar Theory. 1875 June 5 Report of the Astronomer Royal to the Board of Visitors. 1875 June 7 Apparatus for Final Adjustment of the Horolog. Journ. Thermal Compensation of Chronometers, by the Astronomer Royal. 1875 Nov. Chart of the Apparent Path of Mars, 1877, R. Astr. Soc. With neighbouring Stars. Also (Month. Not. ) Spectroscopic Observations made at the Royal Observatory, Greenwich. Also Observations of the Solar Eclipse of 1875, September 28-29, made at the Royal Observatory, Greenwich. 1876 Jan. Report by the Astronomer Royal on the R. Astr. Soc. Present state of the Calculations in his (Month. Not. ) New Lunar Theory. 1876 Jan. 27 Note on a point in the life of Sir William Athenaeum. Herschel. 1876 Mar. 15 Evidence given before the Government Committee on the Meteorological Committee. 1876 May 20 On Toasting at Public Dinners. Public Opinion. 1876 June 3 Report of the Astronomer Royal to the Board of Visitors, 1876 Aug. 7 On a Speech attributed to Nelson. Athenaeum. 1876 Dec. Spectroscopic Results for the Rotation of R. Astr. Soc. Jupiter and of the Sun, obtained at the (Month. Not. ) Royal Observatory, Greenwich. 1877 Jan. Stars to be compared in R. A. With Mars, R. Astr. Soc. 1877, for Determination of the Parallax (Month. Not. ) of Mars. 1877 Mar. Note by the Astronomer Royal on the R. Astr. Soc. Numerical Lunar Theory. Also Remarks (Month. Not. ) on Le Verrier's intra-Mercurial Planet. Also on Observations for the Parallax of Mars. 1877 Mar. 27 Remarks on a Paper on "The River Inst. C. E. Thames. " (Minutes. ) 1877 Apr. On observing for Le Verrier's intra-Mercurial R. Astr. Soc. Planet. Also on the Parallax of (Month. Not. ) Mars, and Mr Gill's proposed expedition. 1877 May On the vulgar notion that the Sun or Moon The Observatory is smallest when overhead. (No. 2). 1877 June 2 Report of the Astronomer Royal to the Board of Visitors. 1877 July 16 Report on the Telescopic Observations of Ho. Of Commons the Transit of Venus 1874, made in the Parly. Paper. Expedition of the British Government, and on the Conclusion derived from those Observations. 1877 Sept. 13 On Spurious Discs of Stars produced by The Observatory oval object-glasses. (No. 7). 1877 Sept. 24 Obituary Notice of the work of Le Daily News. Verrier--died Sept. 23, 1877. 1877 Nov. 20 On the Value of the Mean Solar Parallax The Observatory &c. From the British telescopic Observations (No. 8). Of the Transit of Venus 1874. Also Remarks on Prof. Adams's Lunar Theory. 1877 Nov. On the Inferences for the Value of Mean R. Astr. Soc. Solar Parallax &c. From the Telescopic (Month. Not. ) Observations of the Transit of Venus 1874, which were made in the British Expedition for the Observation of that Transit. 1877 Numerical Lunar Theory: Appendix to Greenwich Astronomical Observations 1875. 1877 Dec. 6 On the Tides at Malta. Phil. Trans. 1878 Correspondence with Le Verrier on his The Observatory Planetary Tables in 1876. (No. 10). 1878 On the Proposal of the French Committee The Observatory to erect a Statue to Le Verrier. Also (No. 13). On the Observation of the approaching Transit of Mercury. 1878 Mar. 11 On the Correction of the Compass in Phil. Mag. Iron Ships without use of a Fixed Mark. 1878 Mar. 30 On the Standards of Length in the The Times. Guildhall, London. 1878 Apr. 27 Report of Lecture on "The probable W. Cumberland condition of the Interior of the Times. Earth. " On the probable condition of the Trans. Of the Interior of the Earth--Revised Cumberland Edition of above Lecture. Assoc. , &c. 1878 June 1 Discussion of the Observations of The Observatory the Transit of Mercury on May 6. (No. 14). 1878 Abstract of Lecture delivered at The Observatory Cockermouth on "The Interior of the (No. 14). Earth. " 1978 June 1 Report of the Astronomer Royal to the Board of Visitors. 1878 July 1 Remarks on the measurement of the The Observatory photographs taken in the Transit of (No. 15). Venus Observations. 1878 July 13 On the Variable Star R. Scuti: The Observatory distortion in the Photo-heliograph. (No. 16). 1878 Remarks on Mr Gill's Heliometric The Observatory Observations of Mars. (No. 20). 1878 Dec. Note on a Determination of the Mass R. Astr. Soc. Of Mars, and reference to his own (Month. Not. ) determination in 1828. Also Note on the Conjunction of Mars and Saturn, 1879, June 30. 1879 Jan. 1 On the remarkable conjunction of The Observatory the Planets Mars and Saturn which (No. 21). Will occur on 1879, June 30. 1879 Feb. 15 On the names "Cabul" and "Malek. " Athenaeum 1879 Feb. 25 On Faggot Votes in Cornwall in 1828. Athenaeum 1879 Mar. 13 Letter on the Examination Papers for the Smith's Prizes. 1879 Apr. 7 Drafts of Resolutions proposed concerning Sadler's Notes on the late Admiral Smyth's "Cycle of Celestial Objects. " 1879 June 1 Letter to Le Verrier, dated 1875, The Observatory Feb. 5, in support of the Method (No. 26). Of Least Squares. 1879 June 1 Remarks in debate on Sadler's The Observatory "Notes" above-mentioned. (No. 26). 1879 June 7 Report of the Astronomer Royal to the Board of Visitors. 1879 July 29 Index to the Records of occasional R. Astr. Soc. Observations and Calculations made (Month. Not. At the Royal Observatory, Greenwich, supplementary. ) and to other miscellaneous Papers connected with that Institution. 1879 Biography of G. B. Airy (perhaps corrected by himself) in French, published at Geneva. 1879 Sept. On the Construction and Use of a Phil. Mag. Scale for Gauging Cylindrical Measures of Capacity. 1880 On the Theoretical Value of the The Observatory Acceleration of the Moon's Mean (No. 37). Motion. 1880 On the Secular Acceleration of The Observatory the Moon--additional note. (No. 37). 1880 Apr. 27 Memoranda for the Commission appointed to consider the Tay Bridge casualty. 1880 Apr. On the Theoretical Value of the R. Astr. Soc. Acceleration of the Moon's Mean (Month. Not. ) Motion in Longitude produced by the Change of Eccentricity of the Earth's Orbit. 1880 May On the Preparations to be made for R. Astr. Soc. Observation of the Transit of Venus (Month. Not. ) 1882, Dec. 6. 1880 On the present Proximity of Jupiter The Observatory to the Earth, and on the Intervals of (No. 42). Recurrence of the same Phaenomena. 1880 June 5 Report of the Astronomer Royal to the Board of Visitors. 1880 Sept. 4 On the _e muet_ in French. Athenaeum. 1880 Sept. 4 Excursions in the Keswick Keswick District. Guardian. 1880 Dec. 1 Description of Flamsteed's The Observatory Equatoreal Sextant, and Remarks on (No. 44). Graham. 1880 Addition to a Paper entitled "On R. Astr. Soc. The Theoretical Value of the Moon's (Month. Not. Mean Motion in Longitude, " &c. Supplementary. ) 1881 Mar. Effect on the Moon's Movement in R. Astr. Soc. Latitude, produced by the slow (Month. Not. ) change of Position of the Plane of the Ecliptic. 1881 June 4 Report of the Astronomer Royal to the Board of Visitors. 1881 Logarithms of the Values of all Inst. C. E. Vulgar Fractions with Numerator and (Minutes. ) Denominator not exceeding 100: arranged in order of magnitude. 1881 July 6 A New Method of Clearing the Lunar Distance. --Admiralty. 1881 Aug. 4 On a Systematic Interruption in the order Phil. Mag. Of numerical values of Vulgar Fractions, when arranged in a series of consecutive magnitudes. 1882 Sept. 15 Monthly Means of the Highest and R. Soc. (Proc. ) Lowest Diurnal Temperatures of the Water of the Thames, and Comparison with the corresponding Temperatures of the Air at the Royal Observatory, Greenwich. 1882 Oct. 19 On the Proposed Forth Bridge. Nature. 1882 Dec. 7 On the Proposed Forth Bridge. Nature. 1883 Jan. 21 On the Ossianic Poems. Athenaeum. 1883 Mar. 12 On the proposed Braithwaite and Daily News. Buttermere Railway. Times. Standard. 1883 Apr. 28 Memorandum on the progress of the Numerical Lunar Theory, addressed to the Board of Visitors of the Royal Observatory, Greenwich. 1883 Letter on The Apparent Inequality in the The Observatory Mean Motion of the Moon. (No. 74). 1883 Aug. 18 On a Singular Morning Dream. Nature. 1883 Sept. 10 Power of organization of the common Nature. Mouse. 1883 Nov. 17 On Chepstow Railway Bridge, with general Nature. Remarks suggested by that Structure. 1884 Mar. 8 On the Erroneous Usage of the term Athenaeum. "arterial drainage. " 1884 On the Comparison of Reversible and The Observatory Non-reversible Transit Instruments. (No. 85). 1884 Nov. 10 On an obscure passage in the Koran. Nature. (?) 1885 May 28 An Incident in the History of Trinity Athenaeum. College, Cambridge. 1885 June 8 Incident No. 2 in the History of Trinity Athenaeum. College, Cambridge. 1885 Nov. 26 Results deduced from the Measure of Phil. Trans. Terrestrial Magnetic Force in the Horizontal Plane, at the Royal Observatory, Greenwich, from 1841 to 1876. 1886 Apr. 6 Integer Members of the First Centenary Nature. Satisfying the Equation A² = B² + C². 1887 Feb. 12 On the earlier Tripos of the University of Nature. (?) Cambridge: in MSS. 1887 Apr. 14 On the Establishment of the Roman Dominion Nature. In South-East Britain. 1887 July 23 On a special Algebraic function, and its Camb. Phil. Soc. Application to the solution of (?) some Equations: in MSS. BOOKS WRITTEN BY G. B. AIRY. Mathematical Tracts on Physical Astronomy, the Figure of the Earth, Precession and Nutation, and The Calculus of Variations. This waspublished in 1826. In a 2nd Edition published in 1831 the UndulatoryTheory of Optics was added to the above list. Four Editions of thiswork have been published, the last in 1858. The Undulatory Theory ofOptics was published separately in 1877. Gravitation: an Elementary Explanation of the Principal Perturbationsin the Solar System. Written for the Penny Cyclopaedia, and publishedpreviously as a book in 1834. There was a 2nd Edition in 1884. Trigonometry. This was written for the Encyclopaedia Metropolitanaabout 1825, and was published as a separate book in 1855 under theTitle of "A Treatise on Trigonometry. " Six Lectures on Astronomy delivered at the meetings of the friends ofthe Ipswich Museum at the Temperance Hall, Ipswich, in the month ofMarch 1848. These Lectures under the above Title, and that of "PopularAstronomy, a series of Lectures, " have run through twelve editions. On the Algebraical and Numerical Theory of Errors of Observations andthe Combination of Observations, 1st Edition in 1861, 2nd in 1875, 3rdin 1879. Essays on the Invasion of Britain by Julius Caesar; The Invasion ofBritain by Plautius, and by Claudius Caesar; The Early Military Policyof the Romans in Britain; The Battle of Hastings, with Correspondence. Collected and printed for private distribution in 1865. An Elementary Treatise on Partial Differential Equations. 1866. On Sound and Atmospheric Vibrations, with the Mathematical Elements ofMusic. The 1st Edition in 1868, the 2nd in 1871. A Treatise on Magnetism, published in 1870. Notes on the Earlier Hebrew Scriptures, published in 1876. Numerical Lunar Theory, published in 1886. INDEX. Accidents (see also Illnesses)AccountsActs and OpponenciesAdams, Prof. J. C. Adams, John QuinceyAgrarian firesAikenAiry, William, father of G. B. A. Airy, Ann, mother of G. B. A. Airy, William, brother of G. B. A. , and Basil R. Airy, his sonAiry, Arthur, brother of G. B. A. Airy, Elizabeth, sister of G. B. A. Airy, Richarda, wife of G. B. A. Airy, children of G. B. A. George Richard Elizabeth Arthur Wilfrid Hubert Hilda Christabel Annot OsmundAllsopAlnwickAltazimuth instrumentAlthorp, LordAmerican ObservatoriesAmerican method of recording Observations (see Galvanic Registration)AmpèreAncient eclipsesAnderson, lessee of Harton CollieryAnemometer (see Meteorology)Anniversary partiesAntiquarian researches and notesAragoArchitecture (see Cathedrals, &c. )Astronomical Society (see Royal Astr. Soc. )Astronomische GesellschaftAthenaeum newspaperAthenaeum ClubAtkinson, Senior Wrangler 1821Atlantic cableAtmospheric railway (see Railways)Auckland, LordAurora BorealisAustralian Observatories (see also Observatories)Auwers, DrBabbage, CharlesBaily, FrancisBakhuysen, of LeydenBalance (Public Balance)Baldock, CommanderBaldrey, assistantBanks, opticianBaring, Sir T. Barlow, Prof. Barlow, W. H. Barnard, ProctorBarnes, MissBarnes, GorellBarometersBarry, Sir C. Barton, BernardBaxter, secretary to the AdmiraltyBeacons, floatingBeaufort, CaptainBeaumont's ObservatoryBedingfield, pupilBell Scholarships (see Examinations)Bessell, astronomerBiddell, Arthur, uncle of G. B. A. Biddell, George, uncle of G. B. A. Biddell, William, uncle of G. B. A. Biddell, George Arthur, son of Arthur BiddellBiographical notesBissett, pupilBlackwood, CaptainBlakesley, CanonBlastingBliss's observationsBlomfield, G. B. , pupilBloomfield, LordBoard of LongitudeBoileauBond, G. P. Books, written by G. B. A. , AppendixBook Society, Cambr. BosanquetBouch, T. Civ. Eng. Boundary of Canada (see Canada)Bouvard, E. BowsteadBradley's observationsBrazil, Emperor ofBreakwaters (see Harbours)Breen, assistantBrewster, Sir D. BridgesBrinkley, DrBristow, MissBritannia Bridge (see Bridges)Brooke, CharlesBritish AssociationBrougham, LordBrowne, G. A. Brunel, Civ. Eng. BuckBuckland, DrBuckle, pupilBurgoyne, Sir J. Burlington, LordBurtonBusts (see Portraits)Calculating machinesCalvertCambridge Observatory: Assistants Instruments Printed observations GeneralCambridge UniversityCambridge Observatory, U. S. A. Canada boundaryCankrein, pupilCanning, LordCape of Good Hope, Observatory and SurveyCarpenter, assistantCartmell, DrCaseCatalogues of stars (see Stars)Cathedrals and churchesCattonCavendish experimentCayley, Prof. Challis, Prof. Chalmers, DrCherbourg (see Harbours)Chesil BankChildersChilders, First Lord of AdmiraltyChristchurchChristie, Prof. Christie, Astronomer RoyalChronographic barrel (see Galvanic Registration)ChronometersChurches (see Cathedrals)Church serviceCincinnati ObservatoryClarendon, LordClark, LatimerClarkson, Thomas, and Mrs ClarksonCleasby, pupilCleggClinton, pupilClocksCockburn, Sir G. Coinage (see Decimal Coinage)Colby, Col. ColchesterColenso, BishopCollege HallCollorado, CountColonial Observatories (see Observatories)CometsCommissionsCompass correctionsCookson, DrCooper, pupilCooper's telescope (see Telescopes)Copying pressCorbaux, MissCorryvreckan whirlpoolCourtney, Rev. J. Cowper, First Commissioner of WorksCrawford, pupilCriswick, assistantCropley, Crosse, Rev. E. Cubitt, Sir W. DaguerrotypesDalhousie, LordDavy, Sir HumphreyDavy, DrDaynou, Lieut. Deal time ballDe BergDecimal coinage and decimal subdividingDee navigation (see Rivers)Degrees (see also Orders and Elections to Societies)Deighton, publisherDe La RiveDe La RueDe LaunayDeluge, TheDe Morgan, A. Denison, E. B. Denison, Sir W. Denison, H. Denmark, King ofDent, clockmakerDent-daleDevonshire, Duke ofDobbs, pupilDobree, lecturerDocks (see Harbours)Dolcoath experimentsDollond, instrument makerDrainageDrinkwater, BethuneDouble-image micrometerDouglas, Sir H. Dover (see Harbours)Dublin professorship (see Professorships)Dublin Observatory (see Observatories)Duë, BaronDundas, AdmiralDundonald, LordDunkin, assistantDunlop, astronomerDurham observatoryEarnshawEarth currentsEastons, manufacturersEclipses (see also Ancient Eclipses)Edinburgh ObservatoryEdmonston, DrEducation (see University Education)Egyptian Astronomical TabletsElections to societies, &c. (see also Degrees and Orders)Electricity, atmosphericEllenborough, LordEllis, W. , assistantElphinstoneEncke and Encke's CometEncyclopaedia MetropolitanaEngines (see Steam-engines)Equatoreal, largeEstcourt, Col. Evans, lecturerExaminationsExhibitions and prizesExodus of the IsraelitesEye, defects ofEye, estate atFallows, astronomerFaradayFarishFarrFellowshipFieldFisherFishmongers' CompanyFletcher, Isaac, M. P. Floating Island, DerwentwaterFluid telescope, Barlow'sFoleyForbes, Prof. J. D. Foster, MessrsFox, AlfredFreedom of the City of LondonFreemantle, Sir T. French, DrFriends, Personal friends at CambridgeFries, Prof. GalbraithGalleGalvanic communication, Time-signals, Clocks, and Registration (see also Earth currents)GambardGas ActGaussGautierGeodesyGeologyGeological SocietyGermanyGibson, pupilGilbert, MessrsGilbert, DaviesGill, astronomerGladstone, W. E. Glaisher, assistantGlasgow ObservatoryGordonGossetGoulburn, Chancellor of the ExchequerGould, Dr B. A. GousselGraduation of circlesGrant, of GlenmoristonGreat Circle sailing (see Navigation)Great Eastern (see Ships)Great ExhibitionGreat GableGreen, Commander U. S. N. GreenwichGreenwich Observatory, before his appointment as Astronomer RoyalGreenwich Observatory: Appointment as Astronomer Royal, and subsequently as Visitor Buildings and grounds in, Instruments Assistants Computations Papers and manuscripts (arrangement of) Estimates Printed Observations Visitations and Reports GeneralGresswellGroombridge's Catalogue (see Stars)Guest, Caius CollegeHaarlemHall, Col. Halley and Halley's CometHamiltonHamilton, Sir W. R. Hamilton, AdmiralHansardHansen, Prof. HansteenHarboursHarcourt, Rev. W. VernonHartnup, astronomerHarton Colliery experimentsHaviland, DrHawkes, Trinity CollegeHebrew ScripturesHeliographHenckeHenderson, astronomerHenslow, Prof. Herbert, G. HerefordHerschel, Sir JohnHerschel, Miss CarolineHerschel, Col. J. Hervey, pupilHigman, Tutor, Trinity CollegeHilgard, U. S. A. Himalaya ExpeditionHind, ModeratorHind, Superintendent Nautical AlmanacHopkinsHovenden, pupilHudsonHuggins, DrHumboldt, Baron A. HumphreysHussey, DrHustler, Tutor, Trinity CollegeHyde Parker, AdmiralHygrometersIbbotson, pupilIliffIllnessesInequality, Venus and EarthInglis, Sir R. Institut de FranceInstitution of Civil EngineersInverness, Northern Institution ofIpswich LecturesIreland, notes ofIvoryJacksonJackson, JohnJames, Sir H. Janus (see Steam-engines)Jarrow (see Harbours)JeffriesJerrard, DrJervis, MajorJeune, Dr, V. C. Of OxfordJohnson, Capt. Johnson, astronomerJones, instrument-makersJones, R. Journeys: Scotland and Cumberland; Swansea; Derbyshire, &c. ; Wales; Keswick, &c. ; Cornwall, &c. ; Orléans; Lake District, &c. ; Continent, Observatories, &c. ; Cornwall, &c. ; Derbyshire; Oxford &c. ; Cumberland; Ireland; Scotland; Derbyshire, &c. ; Cumberland, &c. ; Ireland; Kent; S. Wales; Luddington and Yorkshire; Border of Scotland; S. Wales; Cumberland and Yorkshire; South of Ireland; Ireland; France; Cornwall; Germany; Petersburg, &c. ; Ireland; Shetland; Scotland; Sweden; Madeira; Cumberland; Cumberland; Oban, &c. ; Italy and Sicily; West Highlands; Switzerland; Central France; Spain (eclipse); Cumberland; West Highlands; West Highlands; Cumberland; Norway; Cumberland; Switzerland; Cumberland; Cumberland; Cumberland; Scotland; Scotland; N. Of Scotland; Ireland; Scotland, &c. ; Cumberland; Cumberland; Cumberland; Cumberland; S. Wales; Cumberland 358; CumberlandJulius Caesar, landing ofJupiter (see Planets)KeelingKennedyKing, JoshuaKingstownKnight, publisherKnighthood, offers ofLagardeLaingLandman, EngineerLangtonLardner, DrLassell, and Lassell's telescopeLatitude determinationsLax, Prof. Lectures: College Professorial MiscellaneousLefevre, J. G. S. Leitch, DrLe VerrierLewis, H. Lewis, Sir G. C. Lightfoot, Rev. DrLighthousesLightningLillingstoneLindsay, LordListing, Prof. Liverpool ObservatoryLivingstone, DrLloyd, DrLloyd, Prof. LockyerLodgeLondon UniversityLondon, Freedom of the CityLong vacations, with pupilsLongitude determinationsLongitude, Board of (see Board of Longitude)Lowe, Chancellor of the ExchequerLubbock, Sir JohnLucas (computer)Lucasian Professorship (see Professorships)Lunar ReductionsLunar Theory and Tables (see also Numerical Lunar Theory)Lyndhurst, LordLyons, Sir E. Macaulay, T. B. Macdonnell, DrMaclean, of Loch BuyMaclear, AstronomerMadras Observatory 101Magnetic Observatory and Magnetism (see also Meteorology, Compass corrections, and Earth currents)Main, RobertMaine Boundary (see Canada)Maiden, Prof. MalkinMaltaMan-Engines (see Mines)Manuscripts (see Papers)Mars (see Planets)Marshman, pupilMarth, A. Martin, Trin. Coll. Maskelyne, astronomerMasonMathematical Investigations (see also Appendix "Printed Papers")Mathematical TractsMathematical subjects inMaudslays and FieldMay, Ransomes and MayMedalsMelbourne UniversityMelville, LordMercury (see Planets)Merivale, DrMeteorologyMeteorsMiddleton, Sir W. MilaudMilitary researchesMiller, Prof. MinesMinto, LordMitchell, astronomerMitchell MissMolesworth, Sir W. Monteagle, LordMonument in Playford churchMoon: Observations of Theory and Tables of (see Lunar Theory and Tables) Reductions of Observations of (see Lunar Reductions) Mass ofMorpeth, LordMorton, Pierce, pupilMurchison, Sir R. Murray, publisherMusgrave, CharlesMusgrave, T. ArchbishopMyersNasmythNautical AlmanacNavigationNeate, pupilNeptune and UranusNewallNewcombe, Prof. New ForestNorthampton, LordNorthumberland TelescopeNumerical Lunar TheoryObservatories: see American, Australian, Beaumont's, Cambridge, Cambridge U. S. A. , Cape of Good Hope, Cincinnati, Colonial, Dublin, Durham, Edinburgh, Glasgow, Greenwich, Liverpool, Madras, Oxford, Paris, Paramatta, Pulkowa, St Helena, WilliamstownOccultationsO'ConnellOgilby, pupilOppolzer, Prof. Opponencies (see Acts and Opponencies)OpticsOrders (see also Degrees and Elections to Societies)Ouvaroff, CountOxford ObservatoryOxford, MiscellaneousPackington, Sir J. Palmerston, LordPapers (see Appendix "Printed Papers")Papers, Arrangement ofParachute, Fall ofParallax (see Sun)Paramatta ObservatoryParker, CharlesParker, Vice-ChancellorParis, DrParis ObservatoryParis ExhibitionParliamentary ElectionsPasleyPaulPeacock, GeorgePearson, DrPeel, Sir RobertPendulum Investigations and ExperimentsPenny CyclopaediaPensionPentlandPercy, BishopPersonal sketchPhilosophical Society, CambridgePhilpott, DrPhotographyPiers (see Harbours)Pinheiro, Lieut. Pipon, Lieut. Plana, astronomerPlanetary influencesPlanetary ReductionsPlanets (see also Transits of Venus)PlantamourPlayfordPlumian Professorship (see Professorships)Pocket-books for ObservationsPogson, astronomerPond, astronomerPortlock, Capt. Portraits, busts, &c. Post Office, (clocks, &c. )Post Office, stamps and envelopesPouilletPrince AlbertPritchard, Rev. C. Prizes (see Exhibitions)Probable errorsProfessorships: Dublin; Lucasian; PlumianPublic Schools CommissionPulkowa ObservatoryPupils: Bedingfield; Bissett; Blomfield; Buckle; Cankrein; Cleasby; Clinton; Cooper; Crawford; Dobbs; Gibson; Guest; Hervey; Hovenden; Ibbotson; Lewis; Marshman; Morton; Neate; Ogilby; Parker; Rosser; Smith; Tinkler; Tottenham; Turner; Wigram; WilliamsonPym, EngineerQueen, H. M. The Queen, Quéroualle, Mdlle deQueteletRailways, near ObservatoryRailway Gauge CommissionRailways, miscellaneousRain (see Meteorology)RainbowsRansomes, also Ransomes and May 17, ReachReflex zenith tubeReligious tests and viewsRepsoldRhodesRichardson, assistantRigaud, Prof. RiversRobinson, DrRobinson, Capt. Rogers, Rev. Rogers, school assistantRomilly, LordRonaldsRose, Rev. H. J. Rosse, Lord, and Rosse's TelescopeRosser, pupilRotheryRothmanRound Down Cliff, blasting ofRouse, Rev. R. C. M. Routh, Dr E. J. Royal Astronomical Society (see alsoAppendix "Printed Papers")Royal Exchange clockRoyal InstitutionRoyal Society (see also Appendix "Printed Papers")Royal Society of EdinburghRüncker, ParamattaRünckerRundellRusbyRussell, Lord JohnSabine, Col. Sadler, H. Saint Helena ObservatorySamudaSaturn (see Planets)Saunders, G. W. BySaw-mills (see Ship timbers)Schehallien, mountainScholarshipScholefieldSchumacherScientific ManualScoop-wheelsScoresby, DrScriptural Researches (see Hebrew Scriptures)Sedgwick, AdamSelwyn, Prof. Senate House Examination (see also University Education)Sewers CommissionSheepshanks, Rev. Richard, and MissSheepshanksSheepshanks Fund and ScholarshipShepherd, clock-makerShip-timbers, Machinery for sawing, Shirreff, Capt. SimmonsSimms, F. W. Simms (see Troughton and Simms)Skeleton formsSly, draughtsmanSmith, Rev. R. Smith, father-in-law of G. B. A. , and Mrs Smith, Smith, the Misses Smith, sisters of Richarda Airy, Susanna; Elizabeth; Georgiana; Florence; CarolineSmith, ArchibaldSmith, M. , pupilSmith's PrizesSmyth, Capt. W. H. Smyth, PiazziSocieties, &c. , Elections to (see Elections)Solar Eclipses (see Eclipses)Solar Inequality (see Sun)Solar System (see Sun)Solar Tables (see Sun)South, Sir JamesSouth's TelescopeSouth-Eastern RailwaySouthamptonSouthey (Poet)SpectroscopySpottiswoodeSpring-Rice, Lord MonteagleStandards of Length and Weight, andStandards CommissionStarsStart PointSteam-enginesStephenson, GeorgeStephenson, RobertSteventonStewart, Prof. BalfourStjerneld, BaronStokes, Prof. Stone, AstronomerStratford, Lieut. Stroganoff, CountStrutt, Lord BelperStrutt, JedediahStruve, OttoStuart, Prof. J. Sun: Miscellaneous Parallax of (see also Transits of Venus) Eclipses of (see Eclipses) Inequality, Venus and Earth Tables ofSurveys (see Trigonometrical Surveys)Sussex, Duke of, SutcliffeSutcliffe, MissSydney UniversitySylvesterSweden, King ofTateTaylor, architectTaylor, First Assistant to Pond, Taylor, H. Telegraphs (see Galvanic communications)Telescopes (see also Cambridge Observatory Instruments, and Greenwich Observatory Instruments)Teneriffe ExperimentThames, the River, Theology (see also Hebrew Scriptures and Colenso)ThermometersThermo-multiplierThirlwall, BishopThomas, assistantThompson, Master Trin. Coll. Thomson, Sir W. Tidal Harbour CommissionTides, Time-signals and Time (see also Galvanic communication, &c. )Time balls (see Time signals)Tinkler, pupilTottenham, pupilTraill, DrTransit Circle, Transits of VenusTrigonometrical SurveyTrinity College, CambridgeTrinity House Tripos Examination (see Senate-House Examination)Troughton and SimmsTulley, opticianTupman, CaptTurner, pupilTurton, Prof. TutorshipUlrich, J. G. Universities (see Cambridge, Dublin, Edinburgh, London, Melbourne, Oxford, Sydney)University Education (see also Smith's Prizes and Senate-House Examination)University Press, Uranus (see Neptune)Valencia (see also Longitude Determinations)Venus (see Planets, and Transits of Venus)Venus and Earth inequality (see Inequality)Vernon Harcourt (see Harcourt)Vetch, Capt. Vibrations of groundVignoles, C. B. , engineerVulliamy, clockmakerWales, Prince ofWalker, ByattWalker, James, engineerWalker, Sydney, Warburton, H. Washington, Capt. Water telescope (see also Fluid telescope)WatsonWaves (see Tides)Webster, M. P. For AberdeenWesternWestminster clock (see also Clocks)Wexford harbour (see Harbours)WheatstoneWhewell, WilliamWhite House, the, Wigram, pupilWilliams, JohnWilliamson, pupilWilliamstown ObservatoryWilson, Prof. WinchesterWinds (see Meteorology)WinningWood, Sir CharlesWood, DrWoodbridge, SuffolkWoodhouse, Prof. Woolwich Academy (see Examinations)Wordsworth, Dr, Master of Trin. Coll. Wordsworth, poetWrede, BaronWynter, Vice-Chancellor, OxfordYolland, Col. York CathedralYoung, Dr