[Illustration]

SCIENTIFIC AMERICAN SUPPLEMENT NO. 488

NEW YORK, MAY 9, 1885

Scientific American Supplement. Vol. XIX, No. 488. 

Scientific American established 1845

Scientific American Supplement, $5 a year. 

Scientific American and Supplement, $7 a year. 

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TABLE OF CONTENTS. 

 PAGEI. CHEMISTRY. --Notes on Three New Chinese Fixed Oils. --Tea oil. --Cabbage oil. --Wood oil. --Paper read by R. H. DAVIES before the Pharmaceutical Society of Great Britain. 7798

II. ENGINEERING AND MECHANICS. --A Visit to the Creusot Works. --Giving a description of the works and the projects undertaken by the proprietors. --With full page of engravings illustrating the Hall of Forges and the 100 ton steam hammer. 7784

 Le Creusot. --Extract of the report of the visit of the American Gun Foundry Board to these works. 7784

 Plan for the Elevated Railway at Paris. --4 figures. 7785

 Engineering Inventions since 1862. --By Sir F. J. BRAMWELL. --Bridge construction. --Pneumatic Foundations. --Construction of tunnels. --Canals and river improvements. --Military engineering appliances. --Uses of cement. --Preservation of wood. 7787

III. PHYSICS, ELECTRICITY, ETC. --Electric Light Apparatus for Military Purposes. --With engraving. 7790

 Electricity and Magnetism. --By Prof. F. E. NIPHER. 7790

 The Hydrodynamic Researches of Prof. Bjerknes. --By C. W. COOKE. --5 figures. 7791

 Electrotyping. --With a full description of the process. 7793

 A New Seismograph. --With engraving. 7793

IV. ART AND ARCHITECTURE. --The Cathedral of the Incarnation at Garden City. 7787

 Movable Market Buildings. --7 figures and engraving of movable flower market at Paris. 7788

 Dinocrates' Project. --With three engravings of landscapes showing human profiles. 7789

 The Babylonian Palace. 7798

V. HORTICULTURE. --The Stone Pine (Pinus Pinea). --With engraving. 7797

VI. HYGIENE, ETC. --The Otoscope. --With engraving. 7794

 State Provision for the Insane. --By C. M. HUGHES, M. D. 7794

VII. MISCELLANEOUS. --The Xylophone. --2 engravings. 7793

 The Courage of Originality. 7795

 A Circular Bowling Alley. --With engraving. 7795

 Patent Office Examination of Inventions. 7795

 The Universal Exposition at Antwerp, Belgium. --With full page engraving. 7797

 The Art of Breeding. 7798

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ACKNOWLEDGMENTS. 

We give in this number of our SUPPLEMENT several articles withillustrations, for which we are indebted to _La Nature_. They areentitled Electric Light Apparatus for Military Purposes, The Otoscope, A New Seismograph, Dinocrates' Project, The Xylophone, Plan of anElevated Railway for Paris. 

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A VISIT TO THE CREUSOT WORKS. 

Here we are at the great forge (Fig. 1), that wonderful creation whichhas not its like in France, that gigantic construction which iron haswholly paid for, and which covers a space of twenty-four acres. Wefirst remark two puddling halls, each of which contains 50 furnacesand 9 steam hammers. It is in these furnaces that the iron is puddled. The ball or bloom thus obtained is afterward taken to the hammer, which crushes it and expels the scoriæ. 

[Illustration: FIG. 1. --THE GREAT HALL OF FORGES AT THE CREUSOT WORKS. ]

The puddler's trade, which is without doubt the most laborious one inmetallurgy, will surely soon be lightened through the use of steam. Two rotary furnaces actuated by this agent have been in operation fora few years at Creusot, and each is yielding 20 tons of iron per day. 

We have but a court of 130 feet in width to cross in order to reachthe rolling mill. At the entrance to this we enjoy one of the mostbeautiful sights that the immense works can offer. For a length of1, 240 feet we perceive on one side a series of rolling machines, andon the other a row of reverberatory furnaces that occasionally giveout a dazzling light. In the intervals are fiery blocks that are beingtaken to the rolling machines, in order to be given the most diverseforms, according to the requirements of commerce. 

The iron obtained by puddling is not as yet in its definite state, butthe rolling mill completes what the puddling hall does in the rough. Five hundred and fifty thousand tons of iron, all shaped, are takenfrom the forge every day. To reach such a result it requires no lessthan 3, 000 workmen and a motive power of 7, 000 horses. 

But do not be appalled at the cost of the coal, for, thanks toingenious processes, the heat lost from the furnaces nearly sufficesto run the boilers. If we remark that a power of one horse does in onehour the equivalent of a man's labor per day, we conclude that thesemachines (which run night and day) represent an army of 160, 000 menthat lends its gratuitous aid to the workmen of the forge. This iswhat is called progress in industry. 

We have just seen that iron is obtained in small masses. These can bewelded upon heating them to 1, 500 or 2, 000 degrees. It is impossibleto manufacture a large piece exempt from danger from the weldings. Cast iron always has defects that are inherent to its nature, andthese are all the more dangerous in that they are hidden. Steel isexempt from these defects, and, moreover, whatever be the size of theingot, its homogeneousness is perfect. This is what has given the ideaof manufacturing from it enormous marine engines and those giganticguns that the genius of destruction has long coveted. 

Ah, if the good sense of men does not suffice to put a limit to theirincreasing progress, bridges, viaducts, and tunnels will take it uponthemselves, if need be, to bar their passage. But, in order to forgelarge ingots, it became necessary before all to increase the power ofthe steam hammer. The Creusot establishment, which endowed metallurgywith this valuable machine, had allowed itself to be eclipsed, not bythe number (for it had 57), but by the dimensions of the largest one. In 1875, the Krupp works constructed one of 50 tons, and their examplewas followed at Perm, St. Petersburg, and Woolwich. It was thenthat Mr. Henry Schneider put in execution a bold project that he hadstudied with his father, that of constructing a 100 ton steam hammer, along with the gigantic accessories necessary (Fig. 2). It becamenecessary to erect a building apart for its reception. This structurecovers a surface of one and three-quarter roods, and reaches a heightof 98 feet in the center. As for the hammer, imagine uprights 25feet in height, having the shape of the letter A, surmounted with acylinder 19½ feet in length and of a section of 3½ square yards. 

[Illustration: FIG. 2. --THE CREUSOT ONE HUNDRED TON STEAM HAMMER. ]

The piston which moves in this cylinder, under a pressure of 5atmospheres, is capable of lifting a weight of 100 tons. The hammer, which is fixed to this piston by a rod, has therefore an ascensionalforce of 88, 000 pounds. It can be raised 16 feet above the anvil, andthis gives it a power three and a third times greater than that of thePrussian hammer. Large guns can therefore be made in France just aswell as in Germany. 

This enormous mass is balanced in space at the will of one man, who, by means of a lever, opens and closes two valves without the leasteffort. This colossal hammer required an anvil worthy of it. Thisweighs 720 tons, and rests upon granite in the center of 196 feet ofmasonry. 

The hammer is surrounded with four furnaces heated by gas, and dutyis done for each of these by steam cranes capable of lifting 350, 000pounds. These cranes take the glowing block from the furnace, placeit upon the anvil, and turn it over on every side at the will of theforeman. Under this hammer a cannon is forged as if it were a merebolt. The piece is merely rough-shaped upon the anvil, and a metalliccar running upon a 36 foot track carries it to the adjusting shop. There the cannon is turned, bored, and rifled, and nothing remains butto temper it, that is to say, to plunge it into a bath after it hasbeen heated white hot. For this purpose an enormous ditch has been dugin which there is a cylindrical furnace, and alongside of it there isa well of oil. The car brings the cannon to the edge of the ditch, anda steam crane performs the operation of tempering with as much ease aswe would temper a knife blade. 

In the presence of such engines of attack it was necessary to thinkof defense. The hammer that forges the cannon also gives us the armorplate to brave it. This time the ingot is flattened under the blows ofthe hammer, and even takes the rounded form of the stern, if it be sodesired. Thus is obtained the wall of steel that we wish. 

Will it be possible to keep up the fight long? In order that one mayget some idea of this for himself, let us rapidly describe an entirelypeaceful contest that took place recently upon the coast of Italy. Tworival plates, one of them English and the other French, were placedin the presence of the Spezia gun, which weighs 100 tons. These plateswere strongly braced with planks and old armor plate. Three shots wereto be fired at each of the plates. 

In the first shot the ball was of hardened cast iron, and weighed1, 990 pounds. The English plate was filled with fissures, while theCreusot did not show a single one. The ball penetrated it about seveninches, and was broken into small pieces. 

In the second shot the projectile was the same, but the charge wasgreater. The shot may be calculated from the velocity, which was 1, 530feet. It was equal to what the great hammer would give were it to fallfrom a height of a hundred yards. The English plate was completelyshivered, while the French exhibited but six very fine fissuresradiating from the point struck. The ball entered 8 inches, and wasbroken as in the first experiment. 

The third shot fired was with a steel ball, against the French plate, the English being _hors de combat_. The penetration was the same; theball was not broken, but was flattened at the point like the head of abolt. 

We should like to speak of those magnificent workshops in which theimmense naval pieces are adjusted, where the shafts of helixes 60feet in length are turned, and of the boiler works, where one may seegenerators that have a heating surface exceeding 2, 000 square feet, for it requires no less than that to supply 8, 000 H. P. , and thustriumph over the force of inertia and those colossal iron-clads. Buthow describe in a magazine article what the eye cannot take in in aday?

Despite all our regrets, we have to pass over some things, but ourduty will not have been performed if we omit the history of the works. 

Creusot, which to-day is a regularly-built city with a population of28, 000 souls, was in 1782 but a poor hamlet called Charbonniere. Theexistence there of a coal bed had long been known, and iron ore hadbeen found not far off. But how establish works in a locality deprivedof a water course, and distant from the large ways of communication?

In 1782 the steam engine, which Watt had just finally improved, removed the first difficulty, and the second was soon to disappear, thanks to a projected canal. An iron foundry was then establishedthere under the patronage of Louis XIV. , while the Queen hadglassworks erected. 

As long as the war lasted the foundry supported itself through castingcannons and balls, but after the year 1815 it became necessary eitherto transform the works or sell them. It was decided to do the latter. The Messrs. Chagot, who became purchasers in the sum of $180, 000, werein turn obliged to sell out in 1826. Creusot was then ceded to Messrs. Manby & Wilson, who already had works at Charenton. At the end ofseven years of efforts this firm made a failure, and, finally, in1836, after six million dollars had been swallowed up, Creusot wasbought for $536, 000, by Messrs. Adolphe & Eugene Schneider & Co. Theperiod of reverses was at an end, and one of continued success wasbegun. 

The new managers had seen that carriage by steam was soon to follow, and open up to metallurgy an entirely new horizon. The works werequickly transformed and enlarged, and in 1838, the first Frenchlocomotive was turned out of them. After locomotives came steamboats. It was then that the necessity of forging large pieces gave the ideaof a steam hammer. 

By a coincidence that can only be explained by the needs of the epoch, the English came upon the same discovery almost at the same time, andthe Creusot patent antedated the English one by only two months. 

Two years afterward, frigates such as the Labrador, Orenoque, Albatros, etc. , of 450 H. P. , were rivaling English vessels on theocean. 

After the death of Mr. Adolphe Schneider, on the 3d of August, 1845, his brother Eugene, left sole manager, displayed an activity thatit would be difficult to exceed. He made himself familiar with theresources and productions of foreign countries and of France, and thenmade up his mind what to do. He desired to make his works the finestin the world, and it has been seen from what precedes that, aftertwenty years of effort, his aim has been attained. What a rapidprogress for so short a time! In 1838, the first locomotive that wasnot of English origin appeared to us like a true phenomenon; a fewyears afterward the Creusot locomotives were crossing the Channel inorder to roll proudly over the railways of a rival nation. 

A general, no matter how skillful, could not conquer with anundisciplined army, so the education of the workmen's children was oneof the things that the founder of this great industrial center hadconstantly in mind. Mr. H. Schneider has continued the work of hisfather, and has considerably extended it, at Creusot as well as in theannexed establishments. The number of pupils who frequent the schoolsexceeded 6, 000 in 1878. 

The work is not confined to educating the children, but a retreat isafforded the parents, without putting them under any restraint. 

After twenty-five years' service a workman receives an income of $100if he is a bachelor, and $150 if married, but upon one condition, however, and that is that he is a Frenchman. For $1. 20 a month he islodged in a pretty little house surrounded with a garden, and, if heis sick, he is attended gratuitously. 

These benefits are not addressed to ingrates, as was proved by theprofound sorrow that reigned in the little city when the death of thebenefactor of Creusot was learned. --_Science et Nature. _

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LE CREUSOT. 

The members of the American Gun Foundry Board visited these works in1883, and give the following in their report: The most important steelworks in France are situated at Le Creusot, and bear the name of thelocation in which they are situated. These works have advanced year byyear in importance and in magnitude since their purchase by Mr. EugeneSchneider. 

This gentleman's death, in 1875, was a source of mourning to thewhole town, the inhabitants of which looked up to him as a father. Thegrateful people have erected to his memory a monument in the marketsquare. 

Under the administration of his son, Mr. Henry Schneider, the fame ofthe products of the works has been enhanced, and the proportionsof the establishment have been much increased. The whole number ofworkmen now employed here and at other points amounts to 15, 000; andit is the great center of industry of the adjoining region. At noother place in the world is steel handled in such masses. 

It would be foreign to the purpose of this report to dwell on the manyobjects of commerce which are supplied from these works, but it issafe to say that no proposed work can be of such magnitude as toexceed the resources of the establishment. 

For the preparation of metal for cannon and armor-plates Le Creusotis thoroughly equipped. The iron is produced on the premises from thepurest imported ores, and the manufacture of the steel is carried onby the most approved application of the open-hearth system with theSiemens furnace; the chemical and mechanical tests are such as tosatisfy the most exacting demands of careful government officials; andthe executive ability apparent in all the departments and the evidentcondition of discipline that pervades the whole establishment inspireconfidence in the productions of the labor. 

The capacity for casting steel is represented by seven open-hearthfurnaces of 18 tons each, equal to 126 tons; and the process ofcasting large ingots is a model of order and security. Ladles capableof holding the contents of one furnace, mounted upon platform cars, are successively filled at a previously determined interval of timeand run on railways to a convenient position over the mould; beforethe first ladle is exhausted the supply from the succeeding one hascommenced to run, and so on to the completion of the casting, thesupply to the mould being uninterrupted during the entire process. Theprecision with which the several ladles are brought into position insuccession makes it entirely unnecessary to provide a common reservoirinto which all the furnaces may discharge. By this process the castingof a 45 ton ingot, which was witnessed by the Board, was effected in23 minutes. 

The process of tempering the gun-tubes was also witnessed by theBoard. The excavation of the pit is, as at St. Chamond, 15 metersdeep, with the furnace at one end and the oil tank (100 tons) at theother. One side of the upright furnace is constructed in the form of adoor, which, by a convenient arrangement for swinging, is made to turnon its hinges. Thus, when the tube is raised to the right temperature, it is seized by the traveling crane, the door of the furnace swungopen, and the tube at once advanced to the tank in which it isimmersed. 

All tubes are immersed in oil the second time, but at a temperaturemuch below that to which they are raised at the first immersion. Thisprocess constitutes the annealing after tempering. 

The manufacture of steel-armor plates is a specialty of Le Creusot, which is engaged in an active competition with the manufacturers ofcompound armor. Plates up to 60 centimeters in thickness and 3 meterswide are forged here; they are tempered after forging, but whatsubsequent treatment they receive was not explained. 

The tempering pit for the plates consists of an excavation ofconvenient size, in the center of which is placed a tank containing180 tons of oil. At the four corners of the pit are furnaces in whichthe plates are raised to a proper temperature. When sufficientlyheated, a plate is seized by a walking crane and immersed in the oil. 

Hoops for cannon are manufactured here in large quantities. They arecut from solid ingots, and those for guns up to 24 centimeters arerolled like railway tires; those for larger calibers are forged on amandrel. Jackets of large size are also manufactured; these are madefrom solid ingots, which, after being forged, are bored out. 

At Le Creusot a remarkable test of hoops was witnessed, whichexemplifies not only the excellence of the manufacture of the steelbut also the exacting character of the French requirements. The hoopsfor naval guns are made with the interior surface slightly conical. When forged, turned, and brought under a hammer, a standard mandrel ofsteel, conically shaped to suit the form of the cone in the hoop, butof a slightly increased diameter, is introduced, the smaller endof the mandrel being able to enter the larger end of the hoop. Themandrel is then forced in by the hammer until its lower edge haspassed through the hoop. The blows are then made to operate on theupper edge, detaching it from the mandrel. Careful measurements aretaken of the diameter of the hoop before and after this test, and itis required that the measurement subsequent to the operation shallshow that the hoop has partially, but not entirely, returned to thediameter that it had before the entrance of the mandrel. This wouldshow that there is left to the metal a small margin within its elasticlimit. A system of manufacture which can comply with such a refinementof exactitude must be very precise. 

Perhaps the most striking feature at Le Creusot is the forge, where isassembled an array of steam hammers not equaled in the world, viz. :

 One 100 ton hammer with a fall of 5 meters. One 40 ton hammer with a fall of 3 meters. One 15 ton hammer with a fall of 3 meters. Two 10 ton hammers with a fall of 2½ meters. One 8 ton hammer with a fall of 2½ meters. 

As the 100 ton hammer at these works is the largest in the world, someparticulars concerning it will be appropriate. 

The foundations are composed of a mass of masonry laid in cementresting on bed rock, which occurs at a depth of 11 meters, an anvilblock of cast iron, and a filling-in of oak timber designed todiminish by its elasticity the vibrations resulting from the blows ofthe hammer. The masonry foundation presents a cube of 600 meters. Its upper surface is covered with a layer of oak about one meter inthickness, placed horizontally, on which rests the anvil block. 

At the Perm foundry in Russia the anvil block for the 50 ton hammeris made in one piece, moulded and cast on the spot it was intended tooccupy. Its weight is 622 tons. At Le Creusot, however, this ideawas not approved, and it was determined to construct the block in sixhorizontal courses, each bedded upon plane surfaces. Each course isformed of two castings, except the upper one, a single block, whichweighs 120 tons and supports the anvil. Thus formed in 11 pieces, itis 5. 6 meters high, 33 square meters at the base, and 7 square metersat the top. Its entire weight is 720 tons. 

The space between the block and the sides of the masonry in which itrests is filled in solidly with oak. The block is thus independent ofthe frame of the superstructure. 

The legs of the frame, inclining toward each other in the form of anA, are secured at their bases to a foundation plate embedded in themasonry. They are hollow, of cast iron, and of rectangular crosssection, each leg in two pieces joined midway of their length byflanges and bolts. The legs are also bound together by four plates ofwrought iron, which, at the same time, holds the guides. The height ofthe legs is 10. 25 meters, and their weight, with the guides, 250 tons. The binding plates weigh together about 25 tons, and the foundationplates 90 tons. 

The entablature of the frame work weighs 30 tons; on it is placed thesteam cylinder, single acting, made in two pieces, each 3 meterslong united by flanges and bolts. The diameter of the cylinder is 1. 9meters, giving a surface of 27, 345 square centimeters (deducting thesection of the rod, which is 36 centimeters in diameter); which, for5 atmospheres, gives a pressure under the piston of about 140 tons. As the weight of the hammer is 100 tons, it is evident that it can beraised with great velocity. 

The stroke of the piston in the cylinder is 5 meters. This heightof fall, multiplied by the 100, 000 kilogrammes of the mass, gives aworking force of 500, 000 kilogrammeters, or about 1, 640 foot tons. Thewidth between the legs is 7. 5 meters, and the free height under thecross ties 3 meters, thus providing ample space for maneuvering largemasses of metal. 

The entire height of this colossal structure from the base of themasonry foundation to the upper part of the steam cylinder is 31meters (102 feet), but notwithstanding this unfavorable condition forstability and the enormous effect resulting from a shock of 500, 000kilogrammeters, everything is so well proportioned that there is butslight vibration. 

The workman who maneuvers the hammer is placed on a platform on oneof the legs, about 3 meters above the floor. He is here protectedfrom the heat reflected from the mass of metal during the operation offorging. 

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PLAN FOR AN ELEVATED RAILWAY AT PARIS. 

Elevated railways have been in operation for a long time in New York, Berlin, and Vienna, and the city of Paris has decided to have recourseto this mode of carriage, so indispensable to large cities. Thequestion of establishing a line of railways in our capital has beenopen, as well known, since 1871. During this period of nearly fourteenyears this grave subject has at various times given rise to seriousdiscussions, in which the most competent engineers have taken part, and numerous projects relating to the solution that it calls for havebeen put forth. 

The problem to be solved is of the most complex nature, and theengineers who have studied it have not been able to come to anagreement except as regards a small number of points. It may even besaid that unanimity exists upon but a single point, and that is thatthe means of locomotion in Paris do not answer the requirements ofthe public, and that there is an urgent necessity for new ones. Thecapital question, that of knowing whether the railway to be builtshall be beneath or above ground, is not yet settled; for, up to thepresent, no project has been prescribed in one direction or the other. 

While some extol the underground solution as being the only onethat, without interfering with circulation in the streets, permitsof establishing a double-track railway capable of giving passageto ordinary rolling stock and of connecting directly with the largelines, others, objecting that such a road could not give satisfactionto the taste of Parisians, and that it would necessitate work out ofproportion to the advantages gained, conclude upon the adoption of anopen air railway. 

Preferences generally are evidently for this latter solution. 

We have received from a learned engineer, Mr. Jules Garnier, aproject for an elevated railway, which appears to us to be very ablyconceived, very well studied out, and which we hasten to make known. 

(1. ) The system is characterized by the following fundamental points:The up and down tracks, instead of being laid alongside of each other, as in an ordinary railway, are superposed upon two distinct platformsforming a viaduct, which is consequently so arranged as to permit ofthe laying of one of the tracks at its lower part and of the other atits upper. 

(2. ) The system of constructing the viaduct is so combined as to becapable of giving passage upon the road to the rolling stock of thelarge lines during the stoppage of the daily passenger trains. 

(3. ) The tracks are connected at the extremities by a curve that hasthe proper incline to compensate for the difference in level betweenthe two, and which has a sufficiently large radius to allow the slopeof the track to be kept within the limits admitted. The running of thetrains is thus uninterrupted. 

(4. ) When two lines of different directions bisect one another, aspecial arrangement permits the passengers from one line to pass tothe other by means of what is called a "tangent" station, withoutthe trains of one line crossing the tracks of another, the purpose ofwhich arrangement is to avoid those accidents that would inevitablyoccur through the crossing of a track by the trains of a transverseline. 

(5. ) The rolling stock is arranged in a manner that allows theentrance and exit of the passengers to be effected with greatpromptness. 

In ordinary avenues, comprising a roadway and two sidewalks, theelevated railway is placed in the axis of the roadway at a sufficientheight to prevent it interfering with the passage of carriages, say14¾ feet above the surface, while in boulevards or avenues of greatwidth, having _contre-allees_[1] bordered by a double row of trees, itis installed in one of the _contre-allees_. 

 [Footnote 1: Paths parallel with the public walks. ]

In the first case (Fig. 1), the viaduct is wholly metallic, whilein the second it comprises masonry arches surmounted by a metallicsuperstructure. The viaduct is formed of independent spans supportedby metallic piers that rest upon masonry foundations (Fig. 2). 

[Illustration: FIG. 1. --PROJECT FOR A PARISIAN ELEVATED RAILWAY. ]

[Illustration: FIG. 2. --LONGITUDINAL ELEVATION. ]

The line will have three kinds of stations, intermediate, "tangent, "and terminal ones. It is at the latter that the two superposed linesare connected by the circular inclined plane. 

The waiting platforms of the intermediate stations will be formedsimply by the widening of the span corresponding to the station. Access to these platforms will be had by stairs running up from theedge of the sidewalk. The passengers will make their exit by means ofcorresponding stairs on the opposite side. (Figs 3 and 4. )

[Illustration: FIG. 3. --A STATION. ]

[Illustration: FIG. 4. --TRANSVERSE SECTION OF STATION. ]

The tangent stations are placed at the meeting point of two lines, which, instead of crossing each other, are bent inward like an X, thetwo parts of which will be tangent to the central point. Throughsuch arrangements the running of the trains will be continuous, anda traveler reaching one of these stations will be able, upon changingtrain, to take at his option any one of the three other directions. 

As may be seen, Mr. Garnier's project presents conditions whichare very favorable to the establishment of an elevated road in theinterior of Paris. Far from injuring the aspect of the great arteriesof our metropolis, the viaduct, as it has been conceived, willcontribute toward giving them a still more imposing look. If thebeautiful is, as has been said, the expression of the useful, anelevated railway, well conceived, may be beautiful. The project ofa subterranean railway is attended with great drawbacks, not onlyas regards the great expense that it would necessitate, but also thedifficulties of constructing it. And there is a still graver objectionto it, and that is that it would oblige travelers to move like molesin dark, cold, and moist tunnels. At Paris, where we are accustomedto a pleasant climate and clear atmosphere, we like plenty of air andbroad daylight. --_La Nature. _

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ENGINEERING INVENTIONS SINCE 1862. [1]

 [Footnote 1: Address of Sir Frederick Joseph Bramwell, F. R. S. , on his election as president of the Institution of Civil Engineers. January 13, 1885. ]

By Sir F. J. BRAMWELL. 

I propose to devote the very limited time at my disposal to theconsideration of some of the most important of those improvementswhich are obviously and immediately connected with civil engineering. I am aware of the danger there is of making a serious mistake, whenone excludes any matter which at the moment appears to be of but atrivial character. For who knows how speedily some development mayshow that the judgment which had guided the selection was entirelyerroneous, and that that which had been passed over was in truth thegerm of a great improvement? Nevertheless, in the interests of timesome risk must be run, and a selection must be made; I propose, therefore, to ask your attention while I consider certain of(following the full title of Division I. ) "The apparatus, appliances, processes, and products invented or brought into use since 1862. "In those matters which may be said to involve the principles ofengineering construction, there must of necessity be but littleprogress to note. 

Principles are generally very soon determined, and progress ensues, not by additions to the principles, but by improvement in the methodsof giving to those principles a practical shape, or by combining inone structure principles of construction which had been hithertoused apart. Therefore, to avoid the necessity of having a pause, inreferring to a work, by finding that one is overstepping the boundaryof principle, and trenching within the domain of construction, I thinkit will be well to treat these two heads together. 

If my record had gone back to just before 1851 (the date of the greatexhibition), I might have described much progress in the principlesof girder construction; for shortly prior to that date, the plaincast-iron beam, with the greater part of the metal in the web, andwith but little in the top and bottom flange, was in common use; andeven in the preparation of the building for that exhibition, it isrecorded that one of the engineers connected therewith had greatdifficulty in understanding how it was that the form of open workgirder, with double diagonals introduced therein (a form which was foryears afterward known as the exhibition girder), was any strongerthan a girder with open panels separated by uprights, and without anydiagonals. But, long before 1862, the Warren and other truss-girdershad come into use, and I am inclined to say that, so far as noveltyin the principle of girder-construction is concerned, I must confinemyself to that combination of principles which is represented by thesuspended cantilever, of which the Forth Bridge, only now in courseof construction, affords the most notable instance. It is difficult tosee how a rigid bridge, with 1, 700 foot spans, and with the necessityfor so much clear headway below, could have been constructed withoutthe application of this principle. 

BRIDGE CONSTRUCTION. 

Pursuing this subject of bridge work, the St. Louis Bridge of Mr. Eadsmay, I think, be fairly said to embody a principle of constructionnovel since 1862, that of employing for the arch-ribs tubes composedof steel staves hooped together. Further, in suspension bridges therehas been introduced that which I think is fairly entitled to rankamong principles of construction, the light upper chain, fromwhich are suspended the linked truss-rods, doing the actual work ofsupporting the load, the rods being maintained in straight lines, andwithout the flexure at the joints due to their weight. In the EastRiver Bridge, New York, there was also introduced that which I believewas a novelty in the mode of applying the wire cables. These were notmade as untwisted cables and then hoisted into place, thereby imposingsevere strains upon many of the wires composing the cable throughtheir flexure over the saddles and elsewhere, but the individualwires were led over from side to side, each one having the lengthappropriate to its position, and all, therefore, when the bridge waserected, having the same initial strain and the same fair play. Withinthe period we are considering, the employment of testing-machines hascome into the daily practice of the engineer; by the use of these heis made experimentally acquainted with the various physical propertiesof the materials he employs, and is also enabled in the largest ofthese machines to test the strength and usefulness of these materials, when assembled into forms, to resist strains, as columns oras girders. I of course do not for one moment mean to say thatexperimental machines were unknown or unused prior to 1862--chaincable testing-machines are of old date, and were employed by our pastPresident, Mr. Barlow, and by others, in their early experiments uponsteel; but I speak of it as a matter of congratulation that, in lieuof such machines being used by the few, and at rare intervals uponsmall specimens, for experimental purposes, they are now employed indaily practice and on a large scale. 

In harbor work we have had the principle of construction employed byMr. Stoney at Dublin, where cement masonry is moulded into the formof the wall for its whole height and thickness, and for such a lengthforward as can be admitted, having regard to the practical limit ofthe weight of the block, and then, the block being carried to itsplace, is lowered on to the bottom, which has been prepared to receiveit, and is secured to the work already executed by groove and tongue. 

It would not be right, even in this brief notice of such a modeof construction, to omit mention of the very carefully thought outapparatus by which the blocks are raised off the seats whereon theyhave been made, and are transported to their destination. It is nosimple undertaking (even in these days) to raise (otherwise thanhydraulically) a weight of 350 tons, which is the weight of theblocks with which Mr. Stoney deals. But he does this by means ofpulley-blocks attached to shears built on the vessel which is totransport the block, and he contrives to lift the weight withoutputting upon his chains the extra strain due to the friction of thenumerous pulleys over which they pass. The height of the lift is onlythe few inches needed to raise the block clear of the quay on which ithas been formed, and this is obtained by winding up the chain by steamgear quite taut, so as to take a considerable strain, but not thatequal to the weight of the block, and then water is pumped into theopposite end of the vessel to that upon which the shears are carried, this latter end rises, and the block is raised off the seat on whichit was formed, without the chains being put to work to do the actuallifting at all. The vessel, with the block suspended to the shear legsand over the bows, is then ready to be removed to the place wherethe block has to be laid. A word must here be said about an extremelyingenious mode of dealing with the slack chain, to prevent itsbecoming fouled, and not paying out properly, when the block is beinglowered. This is accomplished by reeving the slack of each chain overtwo fixed sets of multiple sheaves. 

A donkey-engine works a little crab having a large drum, the chainfrom which is connected with the main chain, and draws it round themultiple sheaves so as to take up the slack as fast as the main crabgives it out. The steam is always on the donkey, which is of suchlimited dimensions that it can do no injury to the chain even when itsfull power is in vain endeavoring to draw it any further; directly, however, the main crab gives more slack, and the chain between it andthe two sets of sheaves falls into a deeper catenary, and one whichtherefore puts less opposition to the motion of the donkey-engine, that engine goes to work and makes a further haul upon the slack, andin this way, and automatically, the slack is kept clear. 

PNEUMATIC FOUNDATIONS. 

A noteworthy instance of the use of pneumatic appliances in cylindersinking for foundations is that in progress at the Forth Bridge. Thewrought-iron cylinders are 70 feet in diameter at the cutting-edge, and have a taper of about 1 in 46. They are, however, at a height of 1foot above low water (that is, at the commencement of the masonry workof the pier) reduced to 60 feet in diameter; at their bottoms there isa roofed chamber, into which the air is pumped, and in which the menwork when excavating, this roof being supported by ample main andcross lattice girders. Shafts with air-locks and pipes for admittingwater and ejecting silt are provided. The air-locks are fitted withsliding doors, worked by hydraulic rams, or by hand, the doors beinginterlocked in a manner similar to that in which railway points andsignals are interlocked, so that one door cannot be opened until theother is closed. The hoisting of the excavated material is done by asteam engine fixed outside the lock, this engine working a shaft onwhich there is a drum inside the lock, the shaft passing air-tightthrough a stuffing box. A separate air-lock, with doors, ladder, etc. , complete, is provided to give ingress and egress for the workmen. I have already adverted to one Scotch bridge; I now have to mentionanother, viz. , the Tay Bridge, also now in course of construction. Here the cylinders are sunk, while being guided, through wrought-ironpontoons, which are floated to their berths, and are then secured atthe desired spot by the protrusion, hydraulically, of four legs, whichbear upon the bottom, and thus, until they are withdrawn, convert thepontoon from a floating into a fixed structure. 

SUBAQUEOUS ENGINEERING. 

I regret that time will not admit of my giving any description of themodes of "cut and cover" which have been proposed for the performanceof subaqueous works; sometimes the proposition has been to do thisby means of coffer-dams, and with the work therefore open to theday-light during execution, and sometimes by movable pneumaticappliances. Consideration of subaqueous works necessarily leads themind to appliances for diving, and although its date is considerablyanterior to 1862, I feel tempted, as I believe the construction isknown to very few of our members, to say a few words about the divingapparatus known as the "Bateau-plongeur, " and used at the "barrage"on the Nile. This consists of a barge fitted with an air-tight cabinprovided with an air-lock, and having in the center of its floora large oval opening, surrounded by a casing standing up above thewater-line. In this casing, another casing slides telescopically, theupper part of which is connected to the top of the fixed casing bya leather "sleeve. " When it is desired to examine the bottom of theriver, the telescopic tube is lowered till it touches the bottom, andthen air is pumped into the cabin until the pressure is sufficient todrive out the water, and thus to expose the bottom. This appears to bea very convenient arrangement for shallow draughts of water. 

Reverting for a moment to Mr. Stoney's work, I may mention that heuses for the greatest depths he has to deal with, when preparing thebed to receive his blocks, a diving apparatus which (while easilyaccessible at all times) dispenses with the necessity of raising andlowering, needed in an ordinary diving-bell to allow of the entranceand exit of the workmen. Mr. Stoney employs a bell of adequate size, from the summit of which rises a hollow cylinder, furnished at thetop with an air-lock, by which access can be obtained to the submergedbell. Beyond the general improvement in detail and in the modeof manufacture, and with the exception of the application of thetelephone, there is probably not much to be said in the way ofinvention or progress in connection with the ordinary dress of thediver. 

THE FLEUSS DIVING APPARATUS. 

But one great step has been made in the diver's art by theintroduction of the chemical system of respiration, the inventionof Mr. Fleuss. He has succeeded in devising a perfectly portableapparatus, containing a chemical filter, by means of which the exhaledbreath of the diver is deprived of its carbonic acid; the diveralso carries a supply of compressed oxygen from which to add to theremaining nitrogen oxygen, in substitution for that which has beenburnt up in the process of respiration. Armed with this apparatus, a diver is enabled to follow his vocation without any air-tubeconnecting with the surface, indeed without any connections whatever. A notable instance of a most courageous use of this apparatus wasafforded by a diver named Lambert, who, during one of the inundationswhich occurred in the construction of the Severn tunnel, descendedinto the heading, and proceeding along it for some 330 yards (with thewater standing some 35 feet above him), closed a sluice door, throughwhich the water was entering the excavations, and thus enabled thepumps to unwater the tunnel. Altogether, on this occasion, this manwas under the water, and without any communication with those above, for one hour and twenty-five minutes. The apparatus has also proved tobe of great utility in cases of explosion in collieries, enablingthe wearer to safely penetrate the workings, even when they have beenfilled with the fatal choke-damp, to rescue the injured or to removethe dead. 

CONSTRUCTION OF TUNNELS. 

With respect to the subject of tunneling thus incidentally introduced, in subaqueous work of this kind, I have already alluded to that whichis done by "cut and cover, " but where the influx of water is a sourceof great difficulty, as it was in the old Thames tunnel (though inthis case for water one should read silt or mud), I do not know thatanything has been devised so ingenious as the Thames tunnel shield;improvement has, however, been made by the application of compressedair. 

In the instance of the Hudson River tunnel, the work was done in themanner proposed so long ago as the year 1830 by Lord Cochrane (EarlDundonald) in that specification of his, No. 6, 018, wherein hediscloses, not merely the crude idea, but the very details needed forcompressed air cylinder-sinking and tunneling, included air-locksand hydraulically-sealed modes for the introduction and extraction ofmaterials. I may, perhaps, be permitted to mention that some few yearsago I devised for a tunnel through the water-bearing chalk a mode ofexcavation by the use of compressed air to hold back the water, andcombined with the employment of a tunneling machine. This work, Iregret to say, was not carried out. But there are, happily, cases ofsubaqueous tunneling where the water can be dealt with by ordinarypumping power, more or less extensive, and where the material iscapable of being cut by a tunneling machine. This was so in the Merseytunnel, and would be in the Channel tunnel. In the Mersey tunnel, andin the experimental work of the Channel tunnel, Colonel Beaumont andMajor English's tunneling machine has done most admirable work. In the7 foot 4 inch diameter heading, in the new red sandstone of the Merseytunnel, a speed of as much as 10 yards forward in twenty-four hourshas been averaged, while a maximum of 11-2/3 yards has been attained;while in the 7 foot heading for the Channel tunnel, in the gray chalk, a maximum speed of as much as 24 yards forward in the twenty-fourhours has been attained on the English side; and with the latermachine put to work at the French end, a maximum speed of as much as27-1/3 yards forward in the twenty-four hours has been effected. Inordinary land tunneling since 1862 there has been great progress, bythe substitution of dynamite and preparations of a similar naturefor gunpowder, and by the improvements in the rock-drills worked bycompressed air, which are used in making the holes into which theexplosive is charged. For boring for water, and for many otherpurposes, the diamond drill has proved of great service, and mostcertainly its advent should be welcomed by the geologist, as it hasenabled specimens of the stratum passed through to be taken in thenatural, unbroken condition, exhibiting not only the material and thevery structure of the rock, but the direction and the angle of the dipof the beds. 

Closely connected with tunneling machines are the machines for"getting" coal. This "getting, " when practiced by manual labor, involves, as we know, the conversion into fragments and dust of a veryconsiderable portion of the underside of the seam of coal, the workmanlaboring in a confined position, and in peril of the block of coalbreaking away and crushing him beneath it. Coal-getting machines, suchas those of the late Mr. Firth, worked by compressed air, reduce toa minimum the waste of coal, relieve the workman of a most fatiguinglabor in a constrained position, and save him from the danger to whichhe is exposed in the hand operation. It is a matter of deep regret onmany grounds, but especially as showing how little the true principlesof political economy are realized by working men, who are usually wellinformed on many other points, that the commercial failure of thesemachines is due to their opposition. In connection with collierywork, and indeed in connection with explosives, in the sense of asubstitution for them of sources of expansion acting more slowly, mention should be made of the hydraulic wedges. The employment ofthese in lieu of gunpowder, to force down the block of coal that hadbeen undercut, is one of the means to be looked to for diminishing theexplosions in collieries. Another substitute for gunpowder is found inthe utilization of the expansion of lime when wetted. This has givenbirth to the lime cartridge, the merits of which are now universallyrecognized, but it is feared that trade prejudices may also preventits introduction. While on this subject of "accidents in mines, " itwill be well to call attention to the investigations that have beenmade into the causes of these disasters, and into the probable partplayed by the minute dust which prevails to so great an extent in drycollieries. 

The experiments of our honorary member, Sir Frederick Abel, on thispoint have been of the most striking and conclusive character, andcorroborate investigations of the late Macquorn Rankine into theorigin of explosions in flour mills and rice mills, which hadpreviously been so obscure. The name of Mr. Galloway should also bementioned as one of the earliest workers in this direction. Atfirst sight, pile driving appears to have but little connection withexplosives, but it will be well to notice an invention which has beenbrought into practical use, although not largely (in this country atall events), for driving piles, by allowing the monkey to fall ona cartridge placed in the cavity in the cap on top of the pile; thecartridge is exploded by the fall, and in the act of explosion drivesdown the pile and raises the monkey; during its ascent, and before thecompletion of its descent, time is found for the removal of the emptycartridge and the insertion of a new one. 

CANALS AND RIVER IMPROVEMENTS. 

In the days of Brindley and of Smeaton, and of the other fathersof our profession, whose portraits are on these walls, canals andcanalized rivers formed the only mode of internal transit which wasless costly than horse traction, and, thanks to their labors, thecountry has been very well provided with canals; but the introductionof railways proved, in the first instance, a practical bar to theextension of the canal system, and, eventually, a too successfulcompetitor with the canals already made. Frequently the route that hadbeen selected by the canal engineer was found (as was to be expected)a favorable one for the competing railway, and the result was, thetowns that had been served by the canal were served by the railway, which was thus in a position to take away even the local traffic ofthe canal. For some time it looked as though canal and canalized rivernavigations must come to an end; for although heavy goods could becarried very cheaply on canals, and with respect to the many works andfactories erected on the canal banks, or on bases connected therewith, there was with canal navigation no item of expense corresponding tothe cost of cartage to the railway stations, yet the smallness of therailway rates for heavy goods, and the greater speed of transit, werefound to be more than countervailing advantages. But when privateindividuals have embarked their capital in an undertaking, they do notcalmly see that capital made unproductive, nor do they refrain fromefforts to preserve their dividends, and thus canal companies setthemselves to work to add to their position of mere owners of waterhighways, entitled to take toll for the use of those highways, thefunction of common carriers, thus putting themselves on a par with therailway companies, who, as no doubt is within the recollection of ourolder members, were in the outset legalized only as mere owners ofiron highways, and as the receivers of toll from any persons who mightchoose to run engines and trains thereon, a condition of thingswhich was altered as soon as it was pointed out that it was utterlyincompatible either with punctuality or with safe working. Thisaddition to the legal powers of the canal companies, made by the actsof 1845 and 1847, has had a very beneficial effect upon the valueof their property, and has assisted to preserve a mode of transportcompeting with that afforded by the railways. Further, the canalproprietors have from time to time endeavored to improve the rate oftransport, and with this object have introduced steam in lieu of horsehaulage, and by structural improvements have diminished the number oflockages. Many years before the period we are considering, there wasemployed, to save time in the lockages and to economize water, thesystem of inclined planes, where, either water-borne in a travelingcaisson, as on the Monklands incline, or supported on a cradle, asin the incline at Newark, in the State of New Jersey, the barges weretransferred from one level to another; but an important improvement oneither of these modes of overcoming a great difference of level is theapplication of direct vertically lifting hydraulic power. A notableinstance of this system was brought before the Institution in a paperread on the "Hydraulic Canal Lift at Anderton, on the River Weaver, "by S. Duer, [2] and another instance exists on the Canal de New Fosse, at Fontinettes, in France, the engineers being Messrs. Clark andStandfield, who have other lifts in progress. This system reduces theconsumption of water and the expenditure of time to a minimum. 

 [Footnote 2: Minutes of Proceedings Inst. C. E. , vol. Xlv. , p. 107. ]

With respect to canalized rivers, the difficulty that must always haveexisted when these rivers (as was mostly the case) were provided withweirs to dam up the water for giving power to mills has been augmentedof late years by the change in the character of floods. It hasfrequently been suggested that in these days of steam motors in lieuof water power, and of railways in lieu of water carriage, the injurydone by obstructing the delivery of floods is by no means compensatedby the otherwise all but costless power obtained, or by thepreservation of a mode of transport competing with railways. It hasthereupon been suggested that it would be in the interests of thecommunity to purchase and extinguish both the manufacturing and thenavigating rights, so as to enable the weirs to be removed, and freecourse to be provided for floods. It need hardly be said, however, that if means could be devised for giving full effect to the riverchannels for flood purposes, while maintaining them for the provisionof motive power and of navigation, it is desirable that this should bedone. The great step in this direction appears to be the employmentof readily or, it may be, of automatically movable weirs. Two veryinteresting papers on this subject by Messrs. Vernon-Harcourt and E. B. Buckley were read and discussed in the session 1879-1880. Thesedealt, I fear exclusively, with foreign, notably with French andIndian, examples. I say I fear, not in the way of imputing blame tothe authors for not having noticed English weirs, but because theabsence of such notice amounts to a confession of backwardness in theadoption of remedial measures on English rivers. An instance, however, of improvement since then has been the construction by Mr. Wiswall, the engineer to the Bridgewater Navigation Company (on the Mersey andIrwell section of that navigation), of the movable Throstle Nest weirat Manchester. It does seem to me that by the adoption of movableweirs, rivers in ordinary times may be dammed up to retain sufficientwater to admit of a paying navigation and water for the mills on theirbanks; while in time of flood they shall allow channels as efficientfor relief as if every weir had been swept away. 

But the great feature of late years in canal engineering is not thepreservation or improvement of the ordinary internal canal, but theprovision of canals, such as the completed Suez canal, the Panamacanal in course of construction, the contemplated Isthmus of Corinthcanal--all for saving circuitous journeys in passing from one sea toanother; or in the case nearer home of the Manchester ship canal, fortaking ocean steamers many miles inland. 

But the old fight between the canal engineer and the railway engineer, or, more properly speaking, between the engineer when he had his canal"stop" on and the same individual when he has his railway "stop"--youwill see that I am borrowing a figure, either from Dombey & Son, whereMr. Feeder, B. A. , is shown to us with his Herodotus "stop" on, or, as is more likely, I am thinking of the organs to be exhibited in theSecond division, "Music, " of that exhibition of which I have the honorto be chairman--I am afraid this is a long parenthesis breakingthe continuity of my observations, which related to the old rivalrybetween canal and railway engineering. I was about to say that thisrivalry was revived, even in the case of the transporting of oceanvessels from sea to sea, for we know that our distinguished member, Mr. Eads, is proposing to connect the Atlantic and Pacific oceans bymeans of a ship railway across the Isthmus of Panama. He suggests thatthe largest vessels should be raised out of the water, in the mannercommonly employed in floating docks, and should then be transferredto a truck-like cradle on wheels, fitted with hydraulic bearing blocks(this being, however, not a new proposition as applied to gravingdocks), so as to obtain practical equality of support for the ship, notwithstanding slight irregularities in the roadway, while heproposes to deal with the question of changes of direction by theavoidance of curves and by the substitution of angles, having at thepoint of junction of the two sides turntables on which the cradleand ship will be drawn; these can be moved with perfect ease, notwithstanding the heavy load, because the turntable will be floatingin water carried in circular tanks. 

The question of preserving the level of the turntable, whetherunloaded, partially loaded, or loaded, is happily met by anarrangement of water ballast and pumping. I cannot pass away from themention of Mr. Eads' work without just reminding you of the successfulmanner in which he has dealt with the mouth of the Mississippi, bywhich he has caused that river to scour and maintain a channel 30 feetdeep at low water, instead of that 8 feet deep which prevailed therebefore his skillful treatment. Neither can I refrain from mentioningthe successful labors of our friend Sir Charles Hartley, in improvingthe navigation of that great European river, the Danube. I am sure weare all rejoiced to see that one of the lectures of the forthcomingseries, that on "Inland Navigation, " is to be delivered by him, and Ido earnestly trust he will remember it is his duty to the Institutionnot to leave important and successful works unreferred to becausethose works happen to be his own. 

I regret that time does not admit of my noticing the many improvedmachines for excavating, to be used either below water or on dry land. I also regret, for similar reasons, I must omit all mention of shipconstruction, whether for the purpose of commerce or of war, a subjectthat would naturally follow that of rivers and of ship railways andcanals, and would have enabled me to speak of the great debt thisbranch of civil engineering owes to the labors of our late member, William Froude, and would have enabled me also to deal with thequestion of material for ships, and with the question of armorplating, in which, and in the construction of ordnance, our pastpresident, Mr. Barlow, and myself, as the two lay members of theOrdnance Committee, are so specially interested. 

MILITARY ENGINEERING APPLIANCES. 

The mention of armor plates inevitably brings to our minds theconsideration of ordnance, but I do not intend to say even a few wordson this head of invention and improvement--a topic to which a wholeevening might well be devoted--because only three years ago mytalented predecessor in this chair, Sir William Armstrong, made it thesubject of his inaugural address, and dealt with it in so masterlyand exhaustive a style as to render it absolutely impossible for meto usefully add anything to his remarks. I cannot, however, leave thisbranch of the subject without mentioning, not a piece of ordnance, buta small arm, invented since the date of Sir William's address. I meanthe Maxim machine gun. This is not only one of the latest, but iscertainly one of the most ingenious pieces of mechanism that has beendevised. The single barrel fires the Martini-Henry ammunition; thecartridges are placed in loops upon a belt, and when this belt isintroduced to the gun, and some five or six cartridges have been drawnin by as many reciprocations of a handle, the gun is ready to commencefiring. After the first shot, which must be fired by the pulling ofa trigger in the ordinary way, the gun will automatically continueto send out shot after shot, until the whole of the cartridges on thebelt are exhausted; and if care is taken before this happens to linkon to the tail of the first belt the head of a second one, and anotherbelt to this, and so on, the firing will be automatically continuous, and at a rate anywhere between one shot per minute and six hundredshots per minute, dependent on the will of the person in charge of thegun, the whole of the operations of loading, firing, and ejecting thecartridge being performed by the energy of the recoil. This perfectlyautomatic action enables the man who works the gun to devote his wholeattention to directing it, and as it is carried on a pivot and canbe elevated and depressed, he can, while the gun is firing, aim thebullets to any point he may choose. 

Since 1862 the power of defending seaports has been added to by theapplication of submarine mines, arranged to be fired by impact alone, or to be fired on impact when (under electrical control) the firingarrangement is set for the purpose, or to be fired electrically fromthe shore by two persons stationed on cross-bearings, both of whommust concur in the act of explosion. These mines are charged withgun-cotton, the development of which owes so much to Sir FrederickAbel, while for purposes of attack the same material, not yet inpractical use for shells, is taken as the charge for torpedoes, whichare either affixed to a spar or are carried in the head of a submergedcigar-shaped body. By a compressed air or by a direct steam impulsearrangement these weapons are started on their course and aredirected, and then the running is taken up by their own enginesoperating on screw propellers, driven by a magazine of compressedair contained in the body of the torpedo. Means are also provided tomaintain the designed level below the water surface. The torpedo mayeither be projected from the war ship itself or from one of thoselaunches which owe their origin to our member, Mr. John IsaacThornycroft, who first demonstrated the feasibility of that which waspreviously considered to be impossible, viz. , the obtaining a speedof twenty miles and over from a vessel not more than 80 feet long. Experiments have been carried on in the United States by CaptainEricsson to dispense with the internal machinery of the torpedo, andto rely for its traverse through the water upon the original impulsegiven to it by a breech-loading gun, carried at the requisite depthbelow the water level in a torpedo boat. This gun, having a feeblecharge of powder at a low gravimetric density, fires the torpedo, and, it is said, succeeds in sending it many yards, and with a sufficientterminal velocity to explode the charge by impact. Also, in the UnitedStates, experiments have been made with a compressed air gun of40 feet in length and 4 inches in diameter (probably by this timereplaced by a gun of 8 inches in diameter), to propel a dart throughthe air, in the front of which dart there is a metallic chambercontaining dynamite. Although no doubt the best engineer is the manwho does good work with bad materials, yet I presume we should notrecommend any member of our profession to select unsuitable materialswith the object of showing how skillfully he can employ them. Onthe contrary, an engineer shows his ability by the choice of thosematerials which are the very best for his purpose, having regard, however, to the relative facilities of carriage, to the power ofsupply in sufficiently large quantities, to the ease with which theycan be worked up or built in, and to the cost. 

USES OF CEMENT. 

Probably few materials have been found more generally useful tothe civil engineer, in works which are not of metal, than has beenPortland cement. It should be noticed that during the last twenty-twoyears great improvements have been made in the grinding and in thequality of the cement. These have been largely due to the laborsin England of our member, Mr. John Grant, to the labors of foreignengineers following in his footsteps, and to the zeal and intelligencewith which the manufacturers have followed up the question, from ascientific as well as from a practical point of view, not restinguntil they were able with certainty to produce a cement such as theengineer needed. I do not know that there is very much to be said inthe way of progress (so far as the finished results are concerned) inthe materials which Portland cement and other mortars are intended tounite. Clean gravel and ballast and clean sand are, I presume, verymuch the same in the year 1884 as they were not only in the year 1862, but as they were in the year 1. The same remark applies to stoneand to all other natural building materials; and, indeed, even theartificial material brick cannot in these days be said to surpass inquality the bricks used by the Romans in this island nineteen hundredyears ago, but as regards the mode of manufacture and the materialsemployed there is progress to be noted. The brick-making machine andthe Hoffmann kiln have economized labor and fuel, while attempts havebeen made, which I trust may prove successful, for utilizing the claywhich is to be found in the form of slate in those enormous moundsof waste which disfigure the landscape in the neighborhood of slatequarries. Certain artificial stones, moreover, appear at last to bemade with a uniformity and a power of endurance, and in respect ofthese qualities compare favorably with the best natural stone, andstill more favorably having regard to the fact that they can be madeof the desired dimensions and shape, thus being ready for use withoutlabor of preparation. 

PRESERVATION OF WOOD. 

Reverting to natural materials, there remains to be mentioned thatgreat class, timber. In new countries the engineer is commonly glad toavail himself of this material to an extent which among us is unknown. For here, day by day, owing to the ready adaptability of metals tothe uses of the engineer, the employment of wood is decreasing. Far, indeed, are we from the practice of not more than a hundred years ago, when it was not thought improper to make the shell of a steam engineboiler of wooden staves. The engineer of to-day, in a country likeEngland, refrains from using wood. He cannot cast it into form, hecannot weld it. Glue (even if marine) would hardly be looked upon asan efficient substitute for a sound weld; and the fact is, that it ispractically impossible to lay hold of timber when employed for tensilepurposes so as to obtain anything approaching to the full tensilestrength. If it be desired to utilize metals for such a purpose, they can be swollen out into appropriate "eyes" to receive the neededconnection; but this cannot be done with wood, for the only way ofmaking an enlarged eye in wood is by taking a piece that is big enoughto form the eye, and then cutting away the superfluous portion of thebody. Moreover, when too much exposed to the weather, and when toomuch covered up, wood has an evil habit of rotting, compared withthe rapidity of which mode of decay the oxidizing of metals isunimportant. Further, one's daily experience of the way in whicha housemaid prepares a fire for lighting is suggestive of theundesirability of the introduction of resinous sticks of timber, evenalthough they may be large sticks, into our buildings. Many attempts, as we know, have been made to render timber proof against these twogreat defects of rapid decay and of ready combustibility, and, asit appears to me, it is in these directions alone one can look forprogress in connection with timber. With respect to the first, it wasonly at the last meeting of the Institution we presented a Telfordmedal and a Telford premium to Mr. S. B. Boulton for his paper "On theAntiseptic Treatment of Timber, " to which I desire to refer all thosewho seek information on this point. With respect to the preservationfrom fire of inflammable building materials, the processes, more orless successful, that have been tried are so numerous that I cannoteven pretend to enumerate them. I will, however, just mention one, theasbestos paint, because it is used to coat the wooden structures ofthe Inventions Exhibition. To the employment of this, I think, it isnot too much to say those buildings owed their escape, in last year'svery dry summer, from being consumed by a fire that broke out in anexhibitor's stand, destroying every object on that stand, but happilynot setting the painted woodwork on fire, although it was charredbelow the surface. I do not pretend to say that a surface applicationcan enable wood to resist the effects of a continued exposure to fire, but it does appear that it can prevent its ready ignition. 

(_To be continued. _)

 * * * * *

THE CATHEDRAL OF THE INCARNATION. 

The Cathedral of the Incarnation, at Garden City, N. Y. , the memorialof Mrs. Cornelia M. Stewart to her husband, Alexander T. Stewart, wasopened April 9, 1885, by impressive religious ceremonies. At precisely11 o'clock the chimes in the cathedral tower rang out a clear andresonant peal, and the people thronged into the building through itstower and transept entrances. 

The effort has been made to reproduce in the cathedral a pure type ofthe Gothic architecture of the thirteenth century, without its ruderand less refined characteristics. The strained and coarse imagesdesigned to illustrate "the world, the flesh, and the devil, "which seem so strange and unapt to American visitors to thegreat Continental cathedrals, are almost entirely omitted in thisreproduction. The carving, too, in deference to the more sensitivetastes and better skill of this age, is far more artistic and naturalthan in the old originals. Flowers in stone are made to resembleflowers, and heads are fashioned after a human pattern, and clustersof figures are modeled in a congruous and modern manner. But asidefrom changes of this kind, the new and magnificent edifice uponHempstead Plains is a perfect example of the elaborate and picturesqueGothic structures of mediæval days. 

It is built of brown sandstone raised in colossal blocks. The spire, floriated richly and graduated with a precise symmetry, rises to anextreme altitude of 220 feet 6 inches. The extreme length is about 170ft. The massive oaken front doors are carved handsomely, and containthe arms of the Stewart family, the Clinch family (Mrs. Stewart'smaiden name), the Hilton family, and those of Bishop Littlejohn, the Episcopal head of the Long Island Diocese. The porch or towerentrance, which is the main entrance to the building, is paved withwhite marble. In the center of the floor the Stewart arms are enameledin brass, showing a shield with a white and blue check, supportedby the figures of a wild Briton and a lion. The crest is a pelicanfeeding its young, and the motto is "_Prudentia et Constantia_. "These heraldic figures are made a special feature of the main aisle. Directly in the center of the auditorium floor the Stewart and Clincharms are impaled, enameled in brass. On the floor in the choir theHilton arms are placed. They bear the patriotic motto "_Ubi libertasibi patria_, " with a deer for a crest. The floor of the ante-chancelpresents the arms of the diocese. Its insular character is especiallyprominent. The shield of barry wavy contains three crosslets, thepeculiar sign of the cathedral. It is supported by dolphins. The crestis a ship, and under all is the sacred motto, "I will set his dominionin the sea. " The workmanship of all these arms is superb. 

By far the most wonderful works of art in the edifice are the windowsof stained glass and the musical facilities. Every window presents atheme suggestive of the Incarnation. The windows of the porch presentseveral of the Old Testament characters and events which prefiguredthe birth of Christ, and over the door leading to the nave are figuresof Adam and Eve and of Abraham and Sarah. The four windows on thesouth side of the nave show the Annunciation, the dream of Joseph, thesalutation of Elizabeth, and the refusal of the stable to the parentsof the infant Redeemer. In the first window of the transept ispresented the inn-keeper's refusal of refuge to Joseph and Mary. Thegreat window of the south transept, in all about thirty feet high, oneof the largest windows in the world, shows the family of Jesse, theancestor of Jesus. Jesse is resting at full length; above him is KingDavid, and all around are figures of his descendants leading up to theVirgin Mary with the Holy Child in her arms. Above all, in the apexof the windows, are the emblems used in prophecies of Christ's coming. The third window of the south transept shows the Nativity, with theBabe in the manger. Two windows in the choir are chosen with specialreference to the regular service of the church. The first representsthe appearance of the star in the east to the shepherds of Bethlehem, introducing the "Gloria in Excelsis, " and the second shows thepresentation of Christ in the temple, suggesting the "Nunc Dimittis, "the "Magnificat, " and the "Benedictus. " Then beautiful representationsare given in the north transept windows of the Magi bringing gifts tothe infant Saviour, and the wise men before King Herod. The windowsof the nave show the flight into Egypt, the massacre of the innocents, and the return to Nazareth. 

The north window of the transept is the most magnificent of all. Itpresents Christ in glory, thus suggesting the "Te Deum. " Jesus sitsenthroned with the angels and archangels, prophets, apostles andmartyrs of the church in all ages bending in adoration before Him, while the heavenly choir are waving palms and chanting music inhonor of Heaven's King. The smaller windows under the roof show thehierarchy of heaven indicating by music and dances the joy of thecelestial world at the scenes of the Incarnation depicted below. Upona bright, sunny day the cathedral is made exquisitely beautiful bythe mellowed radiance of these windows. They were designed andmanufactured by Clayton & Bell, of London, and are esteemed to presentthe perfection of their work. Their colors, rich and varied, blend inperfect harmony, and the intricacy of the groupings makes each one asinteresting as an oil painting. 

Six different organs have been built in different parts of thebuilding. The most important of these is the great organ in thenorth apse. It is furnished with four keyboards and 124 stops, withtwenty-four combination stops that admit of more than a millioncombinations of sound. On either side of the choir is another organ, with a fourth of great power in the crypt, a fifth in the tower, andan echo organ built under the vaulting of the roof. This produces asoft and weird music. All the organs are operated from the keyboard ofthe great apse organ, which also plays the chimes of thirteen bellsin the tower. The choir instruments are made to correspond by meansof iron tubes filled with wind by a bellows engine in the crypt of theapse. A second engine in the crypt of the tower operates the bellowsthat inflate the instruments in the crypt, the tower, and thevaulting. All the organs and the chimes are connected by electricwires, about twenty-six miles of which are employed, supplied withelectricity by a motor in the tower engine room. Sublime and grand arethe only terms which can suggest the effect of the volume of harmonyproduced by these instruments in united action. They were made byHilborne L. Roosevelt, of this city. 

The ante-chancel contains the bishop's throne, the dean's seat, andthe stalls of the clergy and canons, all of carved mahogany. A superbwork of art is the altar, in the chancel, which is separated fromthe ante-chancel by a heavy bronze railing. The altar is of statuarymarble manufactured by Cox & Sons, of London. Its corner columns areof black marble, supported by others of flecked marble, with panelsof Sienna and Griote. Between the panels are rich carvings, donein Antwerp, representing the temptation and fall in Eden; Abraham'soffering of his son Isaac; Moses raising the brazen serpent in thewilderness; the annunciation to the Virgin; the birth scene in thestable; the Crucifixion and the Resurrection. The slab of the altaris inlaid with five crosslets, representing the five wounds, and thesymbol "I. H. S. "

None of the cathedral windows are richer than those which circle thechancel. They present Christ as the Good Shepherd and the apostoliccollege. An excellent piece of chiseling is done by Sibbel, thesculptor of this city, in the panels over the credence. They arefigures of the high priest with a slain lamb, the type of the bloodysacrifice, and Christ with sheaves of wheat and clusters of grapes, the unbloody sacrifice. Beneath them is the text, "Thou art a prophetforever after the order of Melchisedec. " The chancel is paved with redand yellow Sienna marble as center pieces, flanked with squares ofred Griote and white marble, the whole bordered with strips of red andblack marble. The ante-chancel is paved with blocks of red Griote andverd antique. Two magnificent pieces of statuary stand on either sideof the transept. The first represents Religion holding a little modelof the cathedral. The other is an image of Hope. They were done byPark, the Florentine sculptor. 

In the south apse is the baptistery, built with a tower furnished withchimes. Its supporting columns are of Languedoc marble clustered withsmaller ones of Sienna and verd antique. Six columns support the dome. Each is of a different marble, crowned with sculptured capitals inhigh relief. The windows are appropriate in theme. They represent Noahwith the ark; the building of the ark; Moses holding the tables of thelaw; the passage of the Red Sea; John the Baptist; the Baptism ofthe eunuch; St. Philip, the deacon; and the Baptism of Christ. Inthe center of the room stands the font upon an octagonal base of twosteps. Its pedestal and bowl are traced with symbolic carvings. Overit is a canopy of elaborately carved mahogany drawn into a spirebearing a gold crown, studded with rubies and amethysts. 

At the foot of the chancel is the pulpit, of bronze, designed bySibbel. Its base is surrounded by figures representing hearers ofthe Word. Mr. Sibbel has incorporated an anachronism in one of thesefigures that will be exceedingly interesting in coming years. It showsthe features of Henry G. Harrison, of this city, the architect of thecathedral. The lectern stands on the other side of the ante-chancel, representing Christ blessing little children. Superb bronze columnswith brass coronas of natural flowers support the roof of thebuilding. The triforium is carved in the richest style with passionflowers, fuchsias, roses, and lilies. 

In the crypt below are the robing rooms of the clergy and the choirand the Sunday-school room. Its windows show the arms of everyAmerican diocese. Beneath the choir is the chantry, furnished incarved oak. Adjoining this room is the famous mausoleum erected to thememory of Alexander T. Stewart. It is constructed of statuary marble, and consists of fourteen bays, at the angles of which are triplecolumns of the most richly colored imported marbles arched abovethe elegantly carved capitals, with open tracery, through which theheadlights of the colored glass are seen. The subjects of the thirteenwindows relate to the passion, death, resurrection, and subsequentappearances of Christ, and are executed in admirable design and color. They were made by Heaton, Butler & Bayne, of London. Above the windowopenings rises a dome-shaped ceiling, in carved marble, with a pendentcanopy in the center. The pavement, of black and white marbles, radiates from the center of the sides of this polygonal structure, anda large white urn, delicately draped after Sibbel's designs, standsunder the pendent canopy. It bears Mr. Stewart's name. The twoentrances to the mausoleum are guarded by open-work bronze gates ofelegant design and workmanship. --_N. Y. Tribune. _

 * * * * *

MOVABLE MARKET BUILDINGS. 

The furnishing of food supplies has always been a question of greatimportance to cities, and there are few of the latter, great or small, where the establishment of markets is not the order of the day. 

At Paris especially, by reason of the massing of the population, whichis annually increasing, the multiplicity of the wants to be satisfiedrenders the solution of this question more and more difficult. The oldmarkets, some of the types of which still exist in various parts ofParis, were built of masonry and wood. They were massive structuresinto which the air and light penetrated with difficulty, and whichconsequently formed a dangerous focus of infection for those whooccupied them, and for the inhabitants of the neighboring houses. Sothe introduction of iron into the construction of markets will bringabout a genuine revolution whose influence will soon make itself feltin all branches of the builder's art. 

The Central Markets were to have been built of masonry, and the workhad even been begun, when, under the pressure of public opinion, thearchitect, Mr. Baltard, was led to use iron. Evidently, the metal thatpermits of covering vast spaces with the use of distant bearing pointsthat present a small surface in plan, and leaves between them wideopenings that the sun and air can enter in quantity, was the onlything that was capable of giving the solution sought. So it hasbeen said, and rightly, that the Central Markets are, as regards thedistribution and rational use of materials, the most beautiful of thestructures of modern Paris. This system of construction at once metwith great success, and the old markets are everywhere graduallydisappearing, in order to give place to the new style of buildings. 

Notwithstanding their number, the Parisian markets long ago becameinsufficient, and wants increased with such rapidity that it becameimpossible to supply them. The municipal administration was thereforeobliged, especially in populous quarters, to tolerate perambulatingpeddlers, who carried their wares in hand carts. This system has thedrawback that it interferes considerably with travel, and especiallyin streets where the latter is most active. Moreover, the merchantsand their goods are exposed to the inclemency of the weather. Inother places, where large spaces were utilizable, such as squares andavenues, very light structures, that could be easily put together andtaken apart, were erected, and markets were opened in these once ortwice a week. This method presents serious advantages. Iron markets, in fact, despite the immense progress that they mark, presentdisadvantages that are inherent to all stationary structures. Itis necessary to erect them in populous centers, where land isconsequently of great value; and the structure itself is costly. 

The result is that the prime cost is very great, and this forces thecity to charge the merchants high rents, and the consumer has to payfor it. With movable markets, on the contrary, the city can utilizelarge areas of unproductive ground, and find new resources, althoughrenting the stalls at a minimum price. The expense connected with thestructure itself is very small. In fact, the distinguishing characterof such structures is their portability--so that the same shed can beused in any number of different places. 

The principal expense, then, will be for carriage; but it is easy tosee that there will always be an economy in their use. This is a fact, moreover, that practice has verified, for it is well known that Parisdoes not get her expenses back from her stationary markets, while themovable ones yield a revenue. 

On another hand, as stationary markets are costly, it results thatthey cannot be multiplied as much as necessary, and so a portion ofthe inhabitants are daily submitted to a loss of time in reaching theone nearest them. 

Finally, from a hygienic standpoint, movable markets present avery great advantage over stationary ones. The latter, in fact, notwithstanding their large open spaces, never get rid of the vitiatedair that they contain, and the bad odors that emanate from them arealso a source of annoyance and danger to the neighborhood. In movableones, on the contrary, when the structure is taken apart, the air, sun, and rain disperse all bad odors, and the place is renderedwholesome in an instant. 

We have now demonstrated what great advantages the city of Paris andher population might derive from the establishing of movable markets. 

It is easy to see that well established structures of this kind wouldrender great services in small towns also. They might entirelyreplace stationary iron markets, the high cost of which often causesmunicipalities to preserve their old, inconvenient, and unhealthystructures. As a general thing, market is held but once or twice aweek in small towns. In the interior the structure could be takenapart, and the place rendered free. 

The question, then, is to have a system of construction that shallsatisfy the different parts of the programme that we have just laidout, that is to say, strength, lightness, rapidity of erection, and ease of carriage. The shelters that are at present employedfor movable markets at Paris are very primitive, and are wanting insolidity and convenience. They consist simply of wooden uprights towhich are affixed cross-pieces that support an impermeable canvas. 

In order to render it possible to extend the system of movablemarkets, it became necessary to first find and study the propermaterial. 

During the year 1883 the city of Paris resolved to make someexperiments, and the Direction of Municipal Affairs commissioned Mr. Andre, director of the Neuilly works, to submit to him a plan for astructure that could be easily taken apart. The plan finally proposedseemed to meet all the requirements of the case, and a group often structures was erected. The trial that was made of these provedentirely satisfactory. The city then made concession to the Neuillycompany, for six years, of the market in Boulevard Richard-Lenoir, of those of La Reine Park, and of the Madeleine flower markets. A sixmonths' trial has shown the great resistance of the materials that weare about to describe in detail. 

The structure is supported by cylindrical hollow iron uprights thatare firmly connected with the ground as follows: At the places wherethey are to be fixed, small catches are inserted in the ground so thattheir upper surface comes flush therewith. These catches consist oftwo cast iron sides bolted together, and of a bottom and ends formedof flat iron--the end pieces being bent so as to form cramp irons. Each of the sides is provided internally with a projecting piece, andan inclined plane as a wedge. In case the catch becomes filled withdirt, it can be easily cleaned out with a scraper. The iron uprightterminates in a malleable cast iron shoe, which is screwed on toit, and which is provided beneath with a projection in the form ofa reversed T, the upper part of the horizontal branches of which isbeveled off in a direction opposite that of the inclined planes of thecatch. This projection enters through the slit and fits into the twowedges, and a simple blow of a hammer suffices to make the adherenceperfect. 

The front and hind uprights differ only in length, and the rooftimbers are joined at their upper extremities. The figures so wellshow how the parts are fitted together as to render an explanationunnecessary. 

The dimensions of these structures vary from 6. 5 to 5. 75 feet inlength by 6. 5 in width and 6 in height. The rafters are prolonged soas to project 4. 25 feet in front, in order to form a protection forthe purchaser. This part of the rafters, as well as the longitudinals, is supported by three curved iron braces, which are put in place asfollows: The timbers are provided with a ring fixed by a screw, andone extremity of the brace is inserted into this, while the other isheld against the upright by a sliding iron socket. The longitudinaltimbers are supported between each two uprights by an iron rod thatrests upon a block of stone fixed in the ground. 

The front ends of the rafters are connected by a longitudinal, 18 feetin length. 

The structure is covered with waterproof canvas held in place bywooden rods, to which it is attached. 

The wood employed is pitch pine. 

An entire market of 300 stalls can be put up in three hours by oneworkman and four assistants. --_Le Genie Civil. _

[Illustration: THE MOVABLE MADELEINE FLOWER MARKET AT PARIS. ] FIG. 1. --GENERAL VIEW OF A MOVABLE MARKET. FIG. 2. --SHOES. FIG. 3. --MODE OF JOINING THE ROOF TIMBERS. FIG. 4. --IRON SUPPORT. FIG. 5. --SECTION OF A SHOE INSERTED IN THE CATCH. FIG. 6. --CATCHES. FIG. 7. --WATERPROOF CANVAS. ]

 * * * * *

DINOCRATES' PROJECT. 

Vitruvius relates that the architect Dinocrates proposed toAlexander the Great to carve Mount Athos in such a way as to give itthe shape of a man, whose one hand should support an entire city, andwhose other should carry a cup which received all the waters from themountain, and from which they overflowed into the sea. 

Alexander, charmed with the idea, asked him if this city was to besurrounded by land capable of supplying it with the grain necessaryfor its subsistence. Having ascertained that the provisioning couldonly be done by sea, Alexander said: "Dinocrates, I grant the beautyof your project; it pleases me, but I think that any one who shouldtake it into his head to establish a colony in the place you proposewould run the risk of being taxed with want of foresight; for, just asa child can neither feed nor develop without the milk of a nurse, soa city cannot increase without fertile fields, have a large populationwithout plenty of food, and allow its inhabitants to subsist withoutrich harvests; so, while giving the originality of your plan myapproval, I have to say to you that I disapprove of the place that youhave selected for putting it into execution. But I want you to staynear me, because I shall have need of your services. "

This gigantic project had doubtless been suggested to the Macedonianarchitect by the singular forms that certain mountains affect. It isnot rare, in fact, to see human profiles delineated upon the sky, and this phenomenon especially happens in countries where the foldedlimestone strata have been broken up in such a way as to give rise todeep valleys perpendicular to the direction of the chain. If we lookat these folds from below in an oblique direction, we shall see themsuperposed upon one another in such a way as to represent figures thatrecall a human profile. 

[Illustration: FIG. 1. LANDSCAPE BY FATHER KIRCHER. ]

In the seventeenth century, Father Kircher conceived the idea oftaking up Dinocrates' plan upon a small scale, and composed thelandscape shown in Fig. 1. The drawing remained engraved for a longtime upon a marble tablet set into the wall of Cardinal Montalte'sgarden at Rome. Later on, artists improved and varied this project, asshown in Figs. 2 and 3. By looking at these cuts from the sides of thepage, it will be seen that they form human profiles. Fig. 2 representsan old woman, and Fig. 3 a man whose beard and hair are formed byshrubbery. 

[Illustration: FIGS. 2 AND 3. --LANDSCAPES SHOWING PROFILES OFHUMAN FACE. ]

We do not think that these conceptions have ever been realized, although Heron in his treatise on Dioptra, and Father Scott in hisParastatic Magic, have described instruments that permit of making thenecessary outlines to cause grounds to present a given aspect froma given point. These instruments consist essentially of a verticaltransparent frame upon which is drawn a vertical projection of thelandscape that it is desired to obtain. 

 * * * * *

In the island of Goa, near Bombay, there is a singular vegetablecalled "the sorrowful tree, " because it only flourishes in the night. At sunset no flowers are to be seen, and yet after half an hour it isfull of them. They yield a sweet smell, but the sun no sooner beginsto shine upon them than some of them fall off, and others close up;and thus it continues flowering in the night during the whole year. 

 * * * * *

THE CRUTO INCANDESCENT LAMP. 

An electrical exhibition on a comparatively small scale was opened inParis, March 22, 1885, with considerable eclat, the President ofthe Republic being present. Engines to the extent of 200 H. P. Areemployed to work the lights. Among the exhibits is the Crutolight. _Engineering_ says: At the first glance it presents the sameappearance as an Edison lamp, having the same form of globe, andapparently a similar luminous filament. But this latter is made inan entirely different manner. A platinum wire is employed, 1/100 ofa millimeter in diameter. This is obtained by the Wollaston process, that is to say, a piece of coarse platinum wire is covered with astout coating of silver, and drawn down till the outside diameteris 1/10 millimeter. The silver coating is then dissolved in a bath ofnitric acid, and the platinum wire is left behind. This wire is thencut into lengths, bent into a U form, and placed in a glass globe, inwhich circulates a current of bicarbonated hydrogen obtained by theaction of sulphuric acid on alcohol. This gas, previously purified, circulates around the platinum filament, through which an electriccurrent is passed sufficient to bring it to a red heat. Thisdecomposes the gas, and a thin coating of absolutely pure carbon isdeposited on the wire. The operation is continued until a sufficientthickness of carbon has been deposited for each type of lamp, and themethod of regulating the amount of deposit is effected verysimply, and, in fact, almost automatically. Indeed, one of the mostinteresting features of the process is its great simplicity, althoughit is somewhat more costly than the ordinary methods of producingincandescence lamps. After having been subjected to the action ofthe gas for two or three hours, the filament is taken from the glassglobe, its diameter is carefully measured, the length is calibrated, and it is set on a platinum support, to which it is soldered by a veryingenious process. The filament is then introduced into a secondglass globe charged with bicarbonate of hydrogen; it is placed betweenpincers that hold the carbon near its union with the platinum, and theplatinum some millimeters below. These pincers are then thrown intocircuit, and a powerful current is passed through the part which isto be soldered. The platinum and carbon become incandescent, thebicarbonate is decomposed, and a fresh deposit of carbon solders thefilament to its support. The system thus mounted is placed within thepermanent globe, and a vacuum is obtained in the ordinary way, whilethe testing and finishing details present nothing of special interest. The finished lamp is then photometrically tested, and placed on asupport something like the Edison mounting. Upon it are engravedthe working constants. As an ordinary practical result, these lamps, working with 50 volts and 1. 15 amperes, give a luminous intensity of20 candles, or the equivalent in luminous spherical intensity of 1. 1Edison A lamps. This result is interesting, especially as the lifeof the lamp ranges from 900 to 1, 100 hours, as was demonstrated byvarious careful tests made with some 250 lamps; the most valuabletrials having taken place at the Turin Exhibition. After prolongeduse, a diminution in the fall of potential is produced, to a moremarked degree than in the Edison lamp, and the light can be maintainedconstant by increasing the strength of the current in a proportionthat can be determined by means of resistances. The Cruto filamentexamined under the microscope appears to be uniformly magnetic, andis very regular, except at the curved parts where the diameter isslightly diminished, and it is here that rupture generally takesplace. The great structural regularity of the filament probablyaccounts for its high durability, and from the fact that it maybe worked with a higher current than probably any other form ofincandescence lamp. M. Desroziers in a series of experiments obtainedas much as 250 carcel spherical luminous value per horse-power; thischaracteristic is one likely to be of great value in electric lightingby incandescence of high intensity. At present only 20-candle lampsare made on the Cruto system. The carbon filament, when properlyprepared, is gray in hue and of metallic appearance; it is built upin very fine laminæ indicating the mode of manufacture. The resultsobtained with these lamps vary as much as 25 per cent. , according tothe care bestowed in producing the filament. If traces of air exist inthe globe, they very quickly manifest themselves by the surface ofthe glass becoming blackened, while an increased energy is required tomaintain the brightness of the light. 

In the early days of this lamp it was thought necessary to removethe delicate platinum wire which forms the core of the filament, byraising the strength of the current sufficiently to destroy it in thecourse of manufacture. This, however, was given up, and the platinumnow remains either as a continuous wire or as a series of smallseparated granules. 

 * * * * *

ELECTRIC LIGHT APPARATUS FOR MILITARY PURPOSES. 

In the first period of the siege of a stronghold it is of very greatimportance for the besieged to embarrass the first progress of theattack, in order to complete their own armament, and to performcertain operations which are of absolute necessity for the safety ofthe place, but which are only then possible. In order to retard thecompletion of the first parallel, and the opening of the fire, it isnecessary to try to discover the location of such parallel, as well asthat of the artillery, and to ply them with projectiles. But, on theirside, the besiegers will do all in their power to hide their works, and those that they are unable to begin behind natural coverts theywill execute at night. It will be seen from this how important it isfor the besieged to possess at this stage of events an effective meansof lighting up the external country. Later on, such means will be ofutility to them in the night-firing of long-range rifled guns, as wellas for preventing surprises, and also for illuminating the breach andthe ditches at the time of an assault, and the entire field of battleat the time of a sortie. 

[Illustration: ELECTRIC LIGHT APPARATUS FOR ARMY USE. ]

On a campaign it will prove none the less useful to be provided withmovable apparatus that follow the army. A few years ago. Lieut. A. Cuvelier, in a very remarkable article in the _Revue Militaire Belge_, pointed out the large number of night operations of the war of 1877, and predicted the frequent use of such apparatus in future wars. 

The accompanying engraving represents a very fine electric lightapparatus, especially designed for military use in mountainouscountries. It consists of a two-wheeled carriage, drawn by one horseand carrying all the apparatus necessary for illuminating the worksof the enemy. The machine consists of the following parts: (1) A fieldboiler. (2) A Gramme electric machine, type M, actuated directly bya Brotherhood 3-cylinder motor. (3) A Mangin projector, 12 inches indiameter, suspended for carriage from a movable support. This latter, when the place is reached where the apparatus is to operate, may beremoved from the carriage and placed on the ground at a distance ofabout a hundred yards from the machine, and be connected therewith bya conductor. Col. Mangin's projector consists of a glass mirror withdouble curvature, silvered upon its convex face. It possesses soremarkable optical properties that it has been adopted by nearlyall powers. The fascicle of light that it emits has a perfectconcentration. In front of the projector there are two doors. Thefirst of these, which is plane and simple, is used when it is desiredto give the fascicle all the concentration possible; the other, whichconsists of cylindrical lenses, spreads the fascicle horizontally, soas to make it cover a wider space. 

The range of the concentrated fascicle is about 86, 000 feet. Theprojector may be pointed in all directions, so as to bring it to bearin succession upon all the points that it is desired to illuminate. The 12-inch projector is the smallest size made for this purpose. The constructors, Messrs. Sautter, Lemonnier & Co. , are making morepowerful ones, up to 36 inches in diameter, with a correspondingincrease in the size of the electric machines, motors, and boilers. 

The various powers make use of these apparatus for the defense offortresses and coasts, for campaign service, etc. 

The various parts of the apparatus can be easily taken apart andloaded upon the backs of mules. The only really heavy piece is theboiler, which weighs about 990 pounds. 

 * * * * *

ELECTRICITY AND MAGNETISM. [1]

 [Footnote 1: Introductory to the course of Lectures on Physics at Washington University, St. Louis, Missouri--_Kansas City Review. _]

Prof. FRANCIS E. NIPHER. 

It was known six hundred years before Christ that when amber is rubbedit acquires the power of attracting light bodies. The Greek name foramber, _elektron_, was afterward applied to the phenomenon. It wasalso known to the ancients that a certain kind of iron ore, firstfound at Magnesia, in Asia Minor, had the property of attractingiron. This phenomenon was called magnetism. This is the history ofelectricity and magnetism for two thousand years, during which thesefacts stood alone, like isolated mountain peaks, with summits touchedand made visible by the morning sun, while the region surrounding andconnecting them lay hidden and unexplored. 

In fact, it is only in more recent times that men could be foundpossessing the necessary mental qualities to insure success inphysical investigation. Some of the ancients were acute observers, andmade valuable observations in descriptive natural history. They alsoobserved and described phenomena which they saw around them, althoughoften in vague and mystical terms. 

They, however, were greatly lacking in power to discriminatebetween the possible and the absurd, and so old wives' tales, acute speculations, and truthful observations are strangely jumbledtogether. With rare exceptions they did not contrive new conditions tobring about phenomena which Nature did not spontaneously exhibit--theydid not experiment. They attempted to solve the universe in theirheads, and made little progress. 

In mediæval times intellectual men were busy in trying to set eachother right, and in disputing and arguing with those who believedthemselves to be right. It was an era of intellectual pugilism, and nothing was done in physics. In fact, this frame of mind isincompatible with any marked success in scientific work. 

The physical investigator cannot take up his work in the spirit ofcontroversy; for the phenomena and laws of Nature will not argue withhim. He must come as a learner, and the true man of science is contentto learn, is content to lay his results before his fellows, and iswilling to profit by their criticisms. In so far as he permits himselfto assume the mental attitude of one who defends a position, in so fardoes he reveal a grave disqualification for the most useful scientificwork. Scientific truth needs no man's defense, but our individualstatements of what we believe to be truth frequently need criticism. It is hardly necessary to remark, also, that critics are of variousdegrees of excellence, and it seems that those in whom the habit ofcriticism has become chronic are of comparatively little service tothe world. 

The great harbinger of the new era was Galileo. There had beenprophets before him, and after him came a greater one--Newton. Theydid nothing of note in electricity and magnetism, but they were filledwith the true spirit of science, they introduced proper and reasonablemethods of investigation, and by their great ability and distinguishedsuccess they have produced a revolution in the intellectual world. Other great men had also appeared, such as Leibnitz and Huyghens; andit became very clear that the methods of investigation which had bornesuch fruit in the days of Galileo were not disposed of completelyby his unwilling recantation; it became very clear that the newcivilization which was dawning upon Europe was not destined to therude fate which had overwhelmed the brilliant scientific achievementsof the Spanish Moors of a half century before. 

Already in 1580, about the time when Galileo entered Pisa as astudent, Borroughs had determined the variation of the magnetic needleat London, and we have upon the screen a view of his instrument, whichseems rude enough, in comparison with the elaborate apparatus of ourtimes. The first great work on electricity and magnetism was the "DeMagnete" of Gilbert, physician of Queen Elizabeth, published in1600. Galileo, already famous in Europe, recognized in the methods ofinvestigation used by Gilbert the ones which he had found so fruitful, and wrote of him, "I extremely praise, admire, and envy this author. "

Gilbert made many interesting contributions to magnetism, which weshall notice in another lecture, and he also found that sulphur, glass, wax, and other bodies share with amber the property of beingelectrified by friction. He concluded that many bodies could not bethus electrified. Gray, however, found in 1729 that these bodies wereconductors of electricity, and his discoveries and experiments wereexplained and described to the president of the Royal Society while onhis death bed, and only a few hours before his death. If precautionsare taken to properly insulate conductors, all bodies which differin any way, either in structure, in smoothness of surface, or even intemperature, are apparently electrified by friction. In all casesthe friction also produces heat, and if the bodies rubbed are exactlyalike, heat only is produced. 

An electrified body will attract all light bodies. This gutta perchawhen rubbed with a cat's skin attracts these bits of paper, and thispith ball, and this copper ball; it moves this long lath balanced onits center, and deflects this vertical jet of water into a beautifulcurve. 

If a conductor is to be electrified, it must be supported by badconductors. This brass cylinder standing on a glass column has becomeelectrified by friction with cat's-skin. My assistant will stand uponthis insulating stool, and by stroking his hand you will observe thatwith his other hand he can attract this suspended rod of wood, and youwill hear a feeble spark when I apply my knuckle to his. 

Du Fay, of Paris, discovered what he called two kinds of electricity. He found that a glass rod rubbed with silk will repel another glassrod similarly rubbed, but that the silk would attract a rubbedglass rod. We express the facts in the well-known law that likeelectricities repel each other, and unlike attract. For a long timethe nature of the distinctions between the two electricities was notunderstood. It was found later that when the two bodies are rubbedtogether they become oppositely electrified, and that the twoelectricities are always generated in equal quantity; so that if thetwo bodies are held in contact after the rubbing has ceased thetwo electricities come together again and the electrical phenomenadisappear. They have been added together, and the result is zero. Franklin proposed to call these electricities positive and negative. These names are well chosen, but we do not know any reason why oneshould be called positive rather than the other. The electricitygenerated on glass when rubbed with silk is called positive. 

Let us now examine the distinction between positive and negativeelectricities somewhat more closely, aiding ourselves by two caseswhich are somewhat analogous. 

Two air-tight cylinders, A and B, contain air at ordinary pressure. The cylinders are connected by a tube containing an air-pump in such away that, when the pump is worked, air is taken from A and forced intoB. To use the language of the electricians, we at once generate twokinds of pressure. The vessels have acquired new properties. If weopen a cock in the side of either vessel, we hear a hissing sound, ifa light body is placed before the opening in A it would be attracted, and before the opening in B it would be repelled. Now this is onlyroughly analogous to the case of the electrified bodies, but theanalogy will nevertheless aid us in our study. If the two vessels arefirst connected with the air, and then closed up and the pump is setto work, we increase the pressure in B and diminish the pressure inA. To do this requires the expenditure of a quantity of work. If thecylinders are connected by an open tube--a conductor--the differencein pressure disappears by reason of a flow of gas from one vessel tothe other. 

If we had a pump by means of which we could pump heat from one bodyinto another, starting with two bodies at the same temperature, thetemperature of one body would increase and that of the other woulddiminish. If we knew less than we do of heat, we might well discusswhether the plus sign should be applied to the heat or to the cold, because these names were coined by people who knew very little aboutthe subject except that these bodies produce different sensations whenthey come in contact with the human body. 

Furthermore, we find that whether the hand is applied to a very hotbody or to a very cold body, the physiological effect is the same. Ineach case the tissue is destroyed and a burn is produced. Shall we nowsay that this burn is produced by an unusual flow of heat from the hotbody to the hand, or from the hand to the cold body, or shall we saythat it is due to an unusual flow of cold from the cold body to thehand, or from the hand to the hot body?

Logically these expressions are identical; still we have come toprefer one of them. It is because we have learned that in those bodieswhich our fathers called hot, the particles are vibrating with greaterenergy than in cold bodies, that we prefer to say that heat is addedand not cold subtracted, when a cold body becomes less cold. 

Now to come back to our electrified bodies. Let us suppose that thisgutta percha, and this cat's-skin are not electrified. That means thattheir electrical condition is the same as that of surrounding bodies. Let us also suppose that their thermal condition is the same assurrounding bodies, ourselves included--that is, they are neither hotnor cold. We express these conditions in other words by sayingthat the bodies have the same electrical _potential_ and the sametemperature. 

Temperature in heat is analogous to potential in electricity. Assoon as adjacent bodies are at different temperatures, we havethe phenomena which reveal to us the existence of heat. As soon asadjacent bodies have different electrical potentials, we have thephenomena which reveal the existence of electricity. As soon asadjacent regions in the air are at different pressures, we havephenomena which reveal the existence of air. 

Bodies all tend to preserve the same temperature and also the sameelectrical potential. Any disturbances in electrical equilibrium aremuch more quickly obliterated than in case of thermal equilibrium, and we therefore see less of electrical phenomena than of thermal. Inthunder storms we see such disturbances, and with delicate instrumentswe find them going on continuously. Changes in temperature occurringon a large scale in our atmosphere, occurring in these gas jets, in our fires, in the axles of machinery, and in thousands of otherplaces, are so familiar that we have ceased to wonder at them. 

If we rub these two bodies together, the potential of the two is nolonger the same. We do not know which one has become greater, and inthis respect our knowledge of electricity is less complete than ofheat. We assume that the gutta percha has become negative. If we nowleave these bodies in contact, the potential of the cat's skin willdiminish and that of the gutta percha will increase until they haveagain reached a common potential--that of the earth. As in the case ofheat and cold, we may say either that this has come about by a flow ofpositive electricity from the cat's skin to the gutta percha, or bya flow of negative electricity in the opposite direction, for thesestatements are identical. 

In case of our gas cylinders, the gas tends to leak out of the vesselwhere the pressure is great into the vessel where it is small. Theheat tends to leak out of a body of high temperature into the colderone, or the cold tends to go in the opposite direction. Similarly, theplus electricity tends to flow from the body having a high potential, to the body having a low potential, or the minus electricity tends togo in the opposite direction. 

 * * * * *

[ENGINEERING. ]

THE HYDRODYNAMIC RESEARCHES OF PROFESSOR BJERKNES. 

BY CONRAD W. COOKE. 

[Illustration: FIG. 1. ]

We have in former articles described the highly interesting seriesof experimental researches of Dr. C. A. Bjerknes, Professor ofMathematics in the University of Christiania, which formed soattractive a feature in the Electrical Exhibition of Paris in 1881, and which constituted the practical development of a theoreticalresearch which had extended over a previous period of more than twentyyears. The experiments which we described in those articles were, as our readers will remember, upon the influence of pulsating andrectilinear vibrating bodies upon one another and upon bodies in theirneighborhood, as well as upon the medium in which they areimmersed. This medium, in the majority of Professor Bjerknes earlierexperiments, was water, although he demonstrated mathematically, andto a small extent experimentally, that the phenomena, which bear sostriking an analogy to those of magnetism, may be produced in air. 

Our readers will recollect that in the spring of 1882 Mr. Stroh, bymeans of some very delicate and beautifully designed apparatus, was able to demonstrate a large number of the same phenomena inatmospheric air of the ordinary density; and about the same timeProfessor Bjerknes, in Christiania, was extending his researches tophenomena produced by a different class of vibrations, namely, thoseof bodies moving in oscillations of a circular character, such, forexample, as a cylinder vibrating about its own axis or a spherearound one of its diameters; some of these experiments were broughtby Professor Bjerknes before the Physical Society of London in thefollowing June. Since that time, however, Professor Bjerknes, with thevery important assistance of his son, Mr. Vilhelm Bjerknes, has beenextending these experimental researches in the same direction, andwith the results which it is the object of the present series ofarticles to describe. 

[Illustration: FIG. 2. ]

The especial feature of interest in all Professor Bjerknes experimentshas been the remarkably close analogy which exists between thephenomena exhibited in his mechanical experiments in water and othermedia and those of magnetism and of electricity, and it may be of someinterest if we here recapitulate some of the more striking of theseanalogies. 

(1. ) In the first place, the vibrating or pulsating bodies, by settingthe water or other medium in which they are immersed into vibration, set up in their immediate neighborhood a field of mechanical forcevery closely analogous to the field of magnetic force with whichmagnetized bodies are surrounded. The lines of vibration haveprecisely the same directions and form the same figures, while at thesame time the decrease of the intensity of vibration by an increase ofdistance obeys precisely the same law as does that of magneticintensity at increasing distances from a magnetic body. 

(2. ) When two or more vibrating bodies are immersed in a fluid, theyset up around them fields of vibration, and act and react upon oneanother in a manner closely analogous to the action and reaction ofmagnets upon one another, producing the phenomena of attractionand repulsion. In this respect, however, the analogy appears to beinverse, repulsion being produced where, from the magnetic analogy, one would expect to find attraction, and _vice versa_. 

(3. ) If a neutral body, that is to say a body having no vibration ofits own, be immersed in the fluid and within the field of vibration, phenomena are produced exactly analogous to the magnetic anddiamagnetic phenomena produced by the action of a magnet upon softiron or bismuth, its apparently magnetic or diamagnetic propertiesbeing determined by the specific gravity of the neutral body ascompared to that of the medium in which it is immersed. If the neutralbody be lighter than the medium, it exhibits the magnetic induction ofiron with respect to polarity, but is nevertheless repelled; whileif it be heavier than the medium, its direction is similar to that ofdiamagnetic bodies such as bismuth, but on the other hand exhibits thephenomena of attraction. 

In this way Professor Bjerknes has been able to reproduce analogues ofall the phenomena of magnetism and diamagnetism, those phenomena whichmay be classed as effects of induction being directly reproduced, while those which may be classed as effects of mechanical action, andresulting in change of place, are analogous inversely. This fact hasbeen so much misunderstood both in this country and on the Continentthat it will be well, before describing the experiments, to enter morefully into an explanation of these most interesting and instructivephenomena. 

For the sake of clearness we will speak of magnetic induction as thatproperty of a magnet by which it is surrounded by a field of force, and by which pieces of iron, within that field, are converted intomagnets, and pieces of bismuth into diamagnets, and we will speak ofmagnetic action as the property of a magnet by which it attracts orrepels another magnet, or by which it attacks or repels a piece ofiron or bismuth magnetized by magnetic induction. 

[Illustration: FIG. 3. ]

The corresponding hydrodynamic phenomena may be regarded in a similarmanner; thus, when a vibrating or pulsating body immersed in aliquid surrounds itself with a field of vibrations, or communicatesvibrations to other immersed bodies within that vibratory field, thephenomena so produced may be looked upon as phenomena of hydrodynamicinduction, while on the other hand, when a vibrating or pulsating bodyattracts or repels another pulsating or vibratory body (whethersuch vibrations be produced by outside mechanical agency or byhydrodynamical induction), then the phenomena so produced are those ofhydrodynamical action, and it is in this way that we shall treat thephenomena throughout this article, using the words _induction_ and_direct action_ in these somewhat restricted meanings. 

[Illustration: FIG. 4. ]

[Illustration: FIG. 5. ]

In the hydrodynamical experiments of Professor Bjerknes all thephenomena of magnetic induction can be reproduced directly andperfectly, but the phenomena of magnetic action are not so exactlyreproduced, that is to say, they are subject to a sort of inversion. Thus when two bodies are pulsating together and in the same phase(i. E. , both expanding and both contracting at the same time), theymutually attract each other: but if they are pulsating in oppositephases, repulsion is the result. From this one experiment taken byitself we might be led to infer that bodies pulsating in similarphases are the hydrodynamic analogues of magnets having their oppositepoles presented to one another, and that bodies pulsating in oppositephases are analogous to a presentation of similar magnetic poles; butit will be seen at once that this cannot be the case if three magneticpoles or three pulsating bodies be considered instead of only two. Itis clear, on the one hand, that three similar magnet poles will allrepel one another, while, on the other, of three pulsating bodies, two of them must always attract one another, while a third would berepelled; and, moreover, two similarly pulsating bodies set up aroundthem the same lines of force as two similar magnetic poles, and twooppositely pulsating bodies produce lines of force identically thesame as those set up by two magnets of opposite polarity. Thus itwill be seen that there is a break in the analogy between thehydrodynamical and the magnetic phenomena (if a uniform inversionof the effects can be called a break, for it is, as far as ProfessorBjerknes' experiments go, without an exception); and if by any meansthis inversion could be reinverted, all the phenomena of magnetism anddiamagnetism could be exactly reproduced by hydrodynamical analogues;there would thus be grounds for forming a theory of magnetism on thebasis of mechanical phenomena, and a very important link in the chainof the correlation of the physical forces would be supplied. 

While the experiments of Professor Bjerknes upon pulsating andrectilinearly vibrating bodies and their influence upon one anotherillustrate by very close analogies the phenomena of magnetism, thoseupon circularly vibrating bodies and their mutual influences bear aremarkable analogy to electrical phenomena; and it is a significantfact that exactly as in the case of magnetic illustration, theanalogies are direct as regards the phenomena of induction, andinverse in their illustration of direct electrical action. 

If we examine the figure produced by the field of force surrounding aconductor through which a current of electricity is being transmitted(see Fig. 1), we see that iron filings within that field arrangethemselves in more or less concentric circles around the conductorconveying the current. From this fact Professor Bjerknes and hisson, reasoning that, to produce a similar field of energy around avibrating body, the vibrations of that body must partake of acircular or rotary character, constructed apparatus for producingthe hydrodynamic analogue of electric currents, in which a conductortransmitting a current of electricity is represented by a cylinder towhich oscillations in circles around its axis are given by suitablemechanical means, so as to cause the enveloping medium to follow itsmotion and make similar rotative vibrations. In some of the earlierexperiments in this direction, cylinders carrying radial veins (A, Fig. 2) or fluted longitudinally around their surfaces (B, Fig. 2)were employed with the object of giving the vibrating cylinder agreater hold of the liquid in which they were immersed; but it wasfound that these vanes or flutings had but little or no effect uponwater or liquids of similar viscosity, and Professor Bjerkes was ledto adopt highly viscous fluids, such as Glycerin or maize sirup, bothof which substances are well adapted for the experiments, being at thesame time both highly viscous and perfectly transparent and colorless. In seeking, for the purpose of this research, a fluid medium whichshall possess analogous properties to the luminiferous ether, orwhatever may be the medium whose vibrations render manifest certainphysical phenomena, it might be considered at first sight thatsubstances so dense as glycerin and sirup could have but little incommon with the ether, and that an analogy between experiments madewithin it and phenomena associated with ethereal vibrations would beof a very feeble description: but Professor Bjerknes has shown thatthe chief requisite in such a medium is that its viscosity should begreat, not absolutely, but large only in proportion to its density, and if the density be small, the necessary viscosity may be smallalso. Neither is it necessary for the fluid medium to possess greatinternal friction, but what is necessary to the experiments is thatthe medium shall be one which is readily set into vibration by theaction of the circularly vibrating cylinder; this property appears tobe possessed exclusively by the more viscous fluids, and is, moreover, in complete accord with what is known of the luminiferous etheraccording to the theory of light. 

The property is rather a kind of elasticity, which ordinary fluidsdo not possess, but which facilitates the propagation of transversevibrations. 

One form of apparatus for the propagation of rotative oscillations isshown to the left of Fig. 3, and consists of a cylinder, A, mounted ona tubular spindle, and which is set into circular oscillations aroundits axis by the little vibrating membrane, C, which is attached tothe axis of the cylinder by a little crank and connecting rod shownin detail in Fig. 4. This membrane is set into vibration by a rapidlypulsating column of air contained in a flexible tube M, by whichapparatus is connected to the pulsation pump which was employed byProfessor Bjerknes in his earlier experiments. In Fig. 5, a somewhatsimilar apparatus for producing horizontal vibrations is shown, andmarked N H C, the only difference between them being one of mechanicaldetail necessitated by the change in the position of axis of vibrationfrom the vertical to the horizontal. 

If circularly vibrating cylinders, such as we have described, beimmersed in a viscous fluid and set into action, the followingphenomena may be observed: 1. The effect upon the fluid itself, setting up therein a field of vibration, and corresponding by analogywith the production of a field of force around a wire conveying anelectric current. 2. The effect upon other circularly vibrating bodieswithin that field of force corresponding to the action and reactionof electric currents upon one another. 3. The effect on pulsating andoscillating bodies similarly immersed, illustrating the mutual effectsupon one another of magnets and electric currents. The first of theseeffects is one of induction, and, from what has been said from anearlier part of this article, it will be understood that the analogybetween the hydrodynamic and the electric phenomena is direct andcomplete. The effects classified under the second and third heads, being phenomena of direct action (in the restricted use of the word), are uniformly analogous to the magnetic and electric phenomena whichthey illustrate. 

(_To be continued. _)

 * * * * *

THE XYLOPHONE. 

Like most musical instruments, the xylophone, had its origin in veryremote times. The Hebrews and Greeks had instruments from which theone of to-day was derived, although the latter has naturally undergonemany transformations. Along about 1742 we find it widely in use inSicily under the name of _Xylonganum_. The Russians, Cossacks, andTartars, and especially the mountain population of the Carpathiansand Ural, played much upon an instrument of the same nature that theycalled _Diereva_ and _Saloma_. 

It appears that the xylophone was played in Germany as early as thebeginning of the 16th century. After this epoch it was in use forquite a long period, but gradually fell into oblivion until thebeginning of the present century. It was toward 1830 that thecelebrated Russian Gussikow undertook a grand artistic voyage throughEurope, and gained a certain renown and received many honors dueto his truly original productions. Gussikow possessed a remarkable_technique_ that permitted the musical instrument which he broughtinto fashion to be appreciated for all its worth. 

[Illustration: FIG. 1. --METHOD OF PLAYING UPON THE XYLOPHONE. ]

As the name, "instrument of wood and straw, " indicates, the xylophone(which Fig. 1 shows the mode of using) consists of small pieces ofwood of varying length, and narrow or wide according to the tone thatit is desired to get from them. These pieces of wood are connectedwith each other by cords so as to form a triangular figure (Fig. 2)that may be managed without fear of displacing the parts. The whole islaid upon bands of straw designed to bring out the sounds and renderthem stronger and purer. The sounds are produced by striking thepieces of wood with a couple of small hammers. They are short andjerky, and, as they cannot be prolonged, nothing but pieces possessinga quick rhythm can be executed upon the instrument. Dances, marches, variations, etc. , are played upon it by preference, and with the besteffect. 

[Illustration: FIG. 2. --PLAN VIEW OF THE XYLOPHONE. ]

The popularity of this instrument is making rapid progress, and itis beginning to be played in orchestras in France [as it has been inAmerica for many years]. A method of using it has just been published, as well as pieces of music adapted to it, with piano, violin, orchestra, etc. , accompaniment. 

 * * * * *

ELECTROTYPING. 

This eminently useful application of the art of electrotypingoriginated with Volta, Cruickshank, and Wollaston about 1800 or 1801. In 1838, Spencer, of London, made casts of coins, and cast in intagliofrom the matrices thus formed; in the same year Jacobi, of Dorpat, inRussia, made casts by electro deposit, which caused him to be put incharge of the work of gilding the dome of St. Isaac at St. Petersburg. 

Electrotyping for the purposes of printing originated with Mr. JosephA. Adams, a wood-engraver of New York, who made casts (1839-41) fromwood-cuts, some engravings being printed from electrotype plates inthe latter year. Many improvements in detail have been added since, in the processes as well as the appliances. Robert Murray introducedgraphite as a coating for the form moulds. He first communicated hisdiscovery to the Royal Institution of London, and afterward received asilver medal from the Society of Arts. 

BLACKLEADING THE FORM. 

The process of electrotyping is as follows: The form is locked up verytightly, and is then coated with a surface of graphite, commonly knownas blacklead, but it is a misnomer. This is put on with a brush, andmay be done very evenly and speedily by a machine in which the brushis reciprocated over the type by hand-wheel, crank, and pitman. Asoft brush and very finely powdered graphite are used; the superfluouspowder being removed, and the face of the type cleaned by the palm ofthe hand. 

TAKING THE MOULD. 

A shallow pan, known as a moulding pan, is then filled with meltedyellow wax, making a smooth, even surface, which is blackleaded. Thepan is then secured to the head of the press, and the form placed onthe bed, which is then raised, delivering an impression of the typeupon the wax. 

The pan is removed from the head of the press, placed on a table, andthen built up, as it is termed. This consists in running wax uponthe portions where large spaces occur between type, in order thatcorresponding portions in the electrotype may not be touched bythe inking roller, or touched by the sagging down of the paper inprinting. 

MAKING THE DEPOSIT. 

The wax mould being built, is ready for blackleading, to give it aconducting surface upon which the metal may be deposited in the bath, superfluous blacklead being removed with a bellows. Blacklead, beingnearly pure carbon, is a poor conductor, and a part of the metal ofthe pan is scraped clean, to form a place for the commencement ofthe deposit. The back of the moulding is waxed, to prevent deposit ofcopper thereon, and the face of the matrix is wetted to drive awayall films or bubbles of air which may otherwise be attached to theblackleaded surface of the type. 

The mould is then placed in the bath, containing a solution ofsulphate of copper, and is made a part of an electric circuit, inwhich is also included the zinc element in the sulphuric-acid solutionin the other bath. A film of copper is deposited on the blackleadsurface of the mould; and when this shell is sufficiently thick, itis taken from the bath, the wax removed, the shell trimmed, the backtinned, straightened, backed with an alloy of type-metal, then shavedto a thickness, and mounted on a block to make it type-high. 

A RECENT IMPROVEMENT. 

has been introduced in which there is added finely pulverized tin tothe graphite for facing the wax mould; the effect in the sulphate ofcopper bath is to cause a rapid deposition of copper by thesubstitution of copper for the tin, the latter being seized by theoxygen, while the copper is deposited upon the graphite. The film isafter increased by the usual means. Knight's expeditious processconsists in dusting fine iron filings on the wet graphite surface ofthe wax mould, and then pouring upon it a solution of sulphate ofcopper. Stirring with a brush expedites the contact, and adecomposition takes place; the acid leaves the copper and forms withthe iron sulphate a solution which floats off, while the copper isfreed and deposited in a pure metallic form upon the graphite. Theblack surface takes on a muddy tinge with marvelous rapidity. Theelectric-connection gripper is designed to hold and sustain themoulding pan and make an electric connection with the preparedconducting pan of the mould only, while the metallic pan itself is outof the current of electricity, and receives no deposit. 

BACKING-UP. 

The thin copper-plate, when removed from the wax mould, is just asminutely correct in the lines and points as was the wax mould, and theoriginal page of type. But it is obvious that the copper sheet is nouse to get a print from. You must have something as solid as the typeitself before it can be reproduced on paper. So a basis of metal isaffixed to the copper film, and this again is backed up with woodthick enough to make the whole type-high. To get this, a man meltssome tinfoil in a shallow iron tray, which he places on the surfaceof molten lead, kept to that heat in square tanks over ordinary fires. The tinfoil sticks to the back of the copper, and on the back of thisis poured melted type-metal, until a solid plate has been formed, thesurface of which is the copper facsimile and the body white metal. Theelectro metal plate, copper colored and bright on its surface, has nowto go to the

FINISHING ROOM. 

Here are two departments. In one the plates are shaved and trimmeddown to fit the wood blocks, which are made in the other department. Some of these operations are done by hand, but it is very interestingto see self-working machines planing the sheets of metal to preciselythe required thinness with mathematical exactness. A pointed tool isset to a certain pitch, and the plate of metal is made to revolvein such a way that one continuous curl shaving falls until the wholesurface (back) has been planed perfectly true. The wood blocks aretreated in the same way, after being sawn into the required sizes by anumber of circular saws. Another set of workmen fit and join the metalto the wood, trim the edges, and turn the blocks out type-high andready for working on the printing press. 

A WET BLACKLEADING PROCESS. 

In Messrs. Harper's establishment in New York, an improved wet processof blackleading is adopted. The wax mould is laid face upward on thefloor of an inclosed box, and a torrent of finely pulverized graphitesuspended in water is poured upon it by means of a rotary pump, ahose, and a distributing nozzle which dashes the liquid equally overthe whole surface of the mould. Superfluous graphite is then removedby copious washing, an extremely fine film of graphite adhering to thewax. This answers a triple purpose; it coats the mould with graphite, wets it ready for the bath, and expels air bubbles from the letters. This process prevents entirely the circulation of blacklead in theair, which has heretofore been so objectionable in the process ofelectrotyping. 

A NEW FOREIGN PROCESS. 

The galvanoplastic process of M. Coblence for obtaining electrotypesof wood-engravings is as follows: A frame is laid upon a marble block, and then covered with a solution of wax, colophane, and turpentine. This mixture on the frame, after cooling, becomes hard, and presents asmooth, even surface. An engraved wooden block is then placed upon thesurface of the frame, and subjected to a strong pressure. The imprinton matrix in cameo, having been coated with graphite, is then placedvertically in a galvanoplastic bath, and a cast, an exact reproductionof the wood-engraving, is obtained. The shell is then backed with typemetal and finished in the usual way. --_Printer and Stationer. _

 * * * * *

A NEW SEISMOGRAPH. 

All the seismographs that have hitherto been employed have two gravedisadvantages: they are either too simple, so that their indicationsare valueless, or too complicated, so that their high cost anddelicacy, and the difficulty of mounting them and keeping them inorder, tend to prevent them from being generally used. 

Seismology will not be able to make any serious progress until it hasat its disposal very certain and very numerous data as to telluricmovements registered at a large number of points at once by accurateinstruments. I have endeavored to construct a simple apparatus capableof automatically registering such facts as it is most necessary toknow in scientific researches on the movements of the earth. Afternumerous experiments I believe that I have succeeded in solving thisdelicate problem, since my apparatus, put to the test of experience, has given me satisfactory results. I have consequently decided tosubmit it to the approval of men of science. 

My seismograph is capable of registering (1) vertical shocks, (2)horizontal ones, (3) the order in which all the shocks manifestthemselves, (4) their direction, and (5) the hour of the firstmovement. 

[Illustration: CORDENONS' SEISMOGRAPH. ]

The apparatus is represented in the accompanying cut. The horizontalshocks are indicated by the front portion of the system, and thevertical ones by the back portion. The hour of the first shock isindicated as follows: The elastic strip of steel, C, is fixed byone of its extremities to a stationary support, d. When, as aconsequence of a vertical motion, the free extremity of this striposcillates, the leaden ball, x, drops into the tube, c, and, onreaching the bottom of this, acts by its shock upon a cord, i, whichactuates the pendulum of a clock that has previously been stopped at12. The other strip, B, is very similar to the one just described, but, instead of carrying a ball, it holds a small metallic cylinder, u, so balanced that a vertical shock in an upward direction causesit to drop forward into the anterior half of the tube to the left. Asecond vertical shock in a downward direction causes it to drop intothe other half. The cylinder, u, and the ball, x, are regulated intheir positions by means of screws affixed to a stationary support. 

The portion of the apparatus designed to register horizontal(undulatory) motions consists of four vertical pendulums, z z z z, each of which is capable of moving in but one direction, since, in theother, it rests against a fixed column. 

Telluric waves, according to modern observations, almost invariablyin every region follow two directions that cross each other at rightangles. When the seismograph has been arranged according to suchdirections, no matter from what part the first horizontal shock comes, one of the four pendulums will be set in motion. If, after the firstundulation in one direction, another occurs in the opposite, thependulum facing the first will in its turn begin to move; and if otherundulations make themselves felt in diametrically opposite directions, the other pendulums will begin to act. These pendulums, in theirmotion, carry along the appendages, e e e e, which are so arrangedas to fall in the center of the marble or iron table, one uponanother, and thus show the order according to which the telluric wavesmanifested themselves. The part of the apparatus that records verticalshocks has a winch, r, which falls at the same place when the leadball drops. 

The apparatus as a whole may be inclosed in a case. When it is desiredto employ it, it should be mounted in a cellar, while the clock thatis connected with it can be located in one of the upper stories of thehouse. --_F. Cordenons, in La Nature_. 

 * * * * *

NOTES ON THREE NEW CHINESE FIXED OILS. [1]

 [Footnote 1: Read at an evening meeting of the Pharmaceutical Society of Great Britain, Feb, 4, 1885. ]

By ROBERT H. DAVIES, F. I. C. , F. C. S. , General Superintendentof Apothecaries' Hall. 

The three oils that form the subject of the examination detailed inthis paper were consigned to a London broker, with a view to theirbeing regularly exported from China if a market could be found forthem here: it was, therefore, necessary to ascertain what commercialoils they resembled in character, so as to estimate to what uses theymight be applied. 

TEA OIL (_Camellia oleifera_). 

In color, transparency, and mobility, this oil considerably resemblesolive oil. The odor and taste, though characteristic, are not easy todescribe. 

(1. ) _Specific Gravity. _--The specific gravity at 60° F. Is 917. 5), water at 60° F. Being taken as 1, 000. 

(2. ) _Action of Cold. _--On subjecting to the cold produced by amixture of pounded ice and salt, some solid fatty matter, probablystearine, separates, adhering to the side of the tube. It takes alonger exposure and a lower temperature than is necessary with oliveoil. I did not succeed in solidifying it, but only in causing somedeposit. Olive oil became solid, while almond and castor oil on theother hand did not deposit at all under similar circumstances. Thelowest temperature observed was -13. 3° C. (8° F. ), the thermometerbulb being immersed in the oil. 

A few qualitative tests, viz. , the action of sulphuric acid, nitricacid (sp. Gr. 1. 42), and digestion, with more dilute nitric acid (1. 2sp. Gr. ) and a globule of mercury, were first tried. 

When one drop of sulphuric acid is added to eight or ten drops of teaoil on a white plate, the change of color observed is more like thatwhen almond oil is similarly treated than with any other oil, oliveoil coming next in order of similarity. 

When a few drops of tea oil are boiled with thirty drops or so ofnitric acid in a small tube, the layer of oily matter, when the briskaction has moderated, is of a light yellow color, similar in tint tothat produced from almond and olive oil under similar circumstances. When the oil is digested with an equal volume of nitric acid (1. 2 sp. Gr. ), and a globule of mercury added, the whole becomes convertedinto a mass of elaidin in about two hours, of the same tint as thatproduced from almond oil when similarly treated. 

These tests point to the fact that the oil may be considered asresembling almond or olive oil in composition, a conclusion which isborne out by the subsequent experiments. 

(3. ) _Free Acidity of Oil. _--The oil was found to contain free acidin small quantity, which was estimated by agitating a weighed quantitywith alcohol, in which the free acid dissolves while the neutral fatdoes not, and titrating the alcoholic liquid with decinormal alkali, using solution of phenol-phthalein as an indicator. 

It was thus found that 100 grammes of the oil require 0. 34 gramme ofcaustic potash to neutralize the free acid. Mr. W. H. Deering (_Journ. Soc. Of Chem. Industry_, Nov. , 1884) states that in seven samples ofolive oil examined by him, the minimum number for acidity was 0. 86 percent. , and the maximum 1. 64 per cent. , the mean being 1. 28 per cent. Tea oil compares favorably with olive oil, therefore, in respect ofacidity, a quality of which note has to be taken when considering theemployment of oil as a lubricating agent. 

(4. ) _Saponification of the Oil. _--Considerable light is thrown on thecomposition of a fixed oil by ascertaining how much alkali is requiredto saponify it. In order to estimate this, a known excess of alcoholicsolution of potash is added to a weighed quantity of the oil, contained in a stout, well-closed bottle (an India-rubber stopper isthe most convenient), which is then heated in a water oven untilthe liquid is clear, no oil bubbles being visible. Phenol-phthaleinsolution being added, the excess of potash is estimated by carefullytitrating with standard hydrochloric acid solution. 

It was thus found that 1, 000 grammes of oil would require 195. 5grammes of caustic potash to convert it entirely into potash soap. 

Koettstorfer, to whom this method of analysis is due, gives 191. 8, andMessrs. F. W. And A. F. Stoddart the numbers 191 to 196, as the amountsof caustic potash required by 1, 000 parts of olive oil. The numbersgiven by niger seed, cotton seed, and linseed oils are very similar tothese. These oils differ from olive and tea oil, however, in having ahigher specific gravity, and in the property they possess of drying toa greater or less extent on exposure to air. 

(5. ) _The Fatty Acids Produced. _--A solution of the potash soap wastreated with excess of hydrochloric acid, and after being well washedwith hot water, the cake of fatty acids was dried thoroughly andweighed. These, insoluble in water, amounted to 93. 94 per cent, of thefat taken. The proportion dissolved in the water used for washing wasestimated by titration with alkali; the quantity of KOH required wasinsignificant, equaling 0. 71 per cent, of the fat originally used. This portion was not further examined. 

The insoluble fatty acids amounted, as last stated, to 93. 94 per cent. Pure olein, supposing none of the liberated acid to be dissolved inwater, would yield 95. 7 per cent. Of fatty acid. 

The acid was evidently a mixture, and had no definite melting point. It was solid at 9° C. , and sufficiently soft to flow at 12° C. , butdid not entirely liquefy under 22° C. To test its neutralizing power, 0. 9575 gramme dissolved in alcohol was titrated with decinormalalkali; it required 34. 05 c. C. This amount of pure oleic acid wouldrequire 33. 95 c. C. ; of pure stearic acid, which has almost the samemolecular weight as oleic acid, 33. 71 c. C. ; or of pure palmitic acid, 37. 4 c. C. This, taken in conjunction with the way in which the acidmelted, makes it extremely probable that it is a mixture of oleic andstearic acids. 

Additional evidence of the large proportion of oleic acid wasfurnished by forming the lead salt, and treating with ether, in whichlead oleate is soluble, the stearate and palmitate being insoluble. Inthis way it was found that the oleic acid obtained from the etherealsolution of the lead salt amounted to 83. 15 per cent. Of the oil. 

This acid was proved to be oleic, by its saturating power and itsmelting point, which were fairly concordant with those of the pureacid. 

CABBAGE OIL (_Brassica, sp. _). 

_Appearance, etc. _--The sample was of a deep brown color, of afluidity intermediate between olive and castor oil, and possessed astrong, rather disagreeable odor. 

_The Specific Gravity at 60° Fahr. _, 914. 0. --The specific gravity ofrape oil and colza oil, both of which are obtained from species of thegenius _Brassica_, varies from 913. 6 to 916. 

_Exposure to Cold. _--This oil by exposure to a temperature of -12°C. (10° F. ) becomes solidified in course of an hour, a brightorange-yellow mass resulting. 

_Qualitative Examination. _--The three reagents before indicated wereapplied to this oil. 

_(a. ) Sulphuric Acid. _--The color produced was very marked andcharacteristic; it differed considerably from any of the otherssimultaneously tested, the nearest to it being olive end rape oil. 

_(b. ) Strong Nitric Acid. _--The reaction was more violent than before, the stratum of oil after cooling being darker in color than in thethree cases before mentioned. The reaction with rape oil was similarin all respects. 

_(c. ) Elaidin Test. _--The solid mass of elaidin formed was of a darkercolor than that from olive, almond, and tea oil, but closely resembledthat from rape oil. 

_Free Acidity. _--This was estimated as above described. 100 grammes ofoil would require 0. 125 gramme caustic potash. The samples of rape oilexamined by Deering (loc. Cit. ) were found to require from 0. 21 to0. 78 KOH per 100 grammes oil. 

_Saponification of the Oil. _--Upon saponifying with alcoholic potash, it was found that 1, 000 grammes of oil required 175. 2 grammes ofpotash for complete saponification. 

The number obtained by Koettstorfer for colza was 178. 7, by Messrs. Stoddart for rape oil, 175-179, and by Deering for rape oil, 170. 8-175. 5. The only other oil of which I can find figures resemblingthese is castor oil, which requires 176-178 grammes per kilo (Messrs. Stoddart). The difference in specific gravity between this (cabbage)oil and castor oil and the solubility of the latter in alcohol pointto a wide distinction between them. Hence I think the numbers abovegiven conclusively demonstrate the resemblance between this oil andrape oil in composition. 

_The Fatty Acids. _--The acids produced by adding HCl to the potashsoap were almost entirely insoluble in water. The actual amount ofpotash required to neutralize the acid in the wash water equaled 0. 20per cent. Of the oil originally taken. 

The insoluble fatty acid amounted to 95. 315 per cent. Of the oiltaken. It was evidently a mixture of two or more fatty acids. Ontrying to take its melting point, I found that it commenced to softenat 17° C. , was distinctly liquid at 19°, but not completely melteduntil 22° C. 

According to O. Bach (Year Book Pharm. , 1884, p. 250), the fatty acidsfrom rape seed oil melt at 20. 7° C. , which is fairly concordant withthe result obtained for cabbage oil acids. 

The neutralizing power of these acids was then tested. 0. 698 grammedissolved in alcohol required 20. 52 c. C. Decinormal alkali. It is asingular coincidence that brassic acid (C_{22}H_{42}O_{2}), which is acharacteristic acid of colza and rape oils, would have required almostexactly this quantity of alkali for neutralization, 0. 698 brassicacid theoretically saturating 20. 69 c. C. Of decinormal alkali. Iam disposed to regard this as a coincidence, since a subsequentexperiment showed that the lead salts formed were partially soluble inether, whereas the lead salt of brassic acid is said to be insolublein this liquid. 

WOOD OIL (_Elæococcus cordata_). 

_Appearance, etc. _--This oil has a decided brown color and apersistent and disagreeable odor. It is rather more fluid than castoroil. Glass vessels containing it soon show a film of apparentlyresinous material, which forms whenever a portion of the oil flowsfrom the lip or edge down the outside of the vessel, and is thusexposed to the air in a thin stream. This drying power is one of itsmost prominent characters. If a few drops be exposed in a flat dish, in the water oven, the oil dries rapidly, so that in two hours thegain in weight will be appreciable, and in four hours the whole willhave become solid. 

_The Specific Gravity at 60° Fahr. _, 940. 15. --This is an unusuallyhigh gravity for a fixed oil. The only two which exceed it are castoroil, which is 960, about, and croton oil, which is very similar tothis, 942 to 943 (A. H. Allen). It is interesting to note that boththese oils are yielded by plants of the natural order _Euphorbiaceæ_, to which the plant yielding so-called wood oil belongs. 

_Exposure to Cold. _--This oil is apparently unaffected by exposure toa temperature of -13. 3° C. (8° F). 

_Qualitative Examination. _--The action of sulphuric acid isremarkable. When a drop comes in contact with the oil, the latterapparently solidifies round the drop of acid, forming a black envelopewhich grows in size and gradually absorbs and acts upon so much of thesurrounding oil as to assume the appearance of a large dried currantof somewhat irregular shape. 

When a drop of the oil is added to nitric acid, it solidifies, andon heating very readily changes into an orange yellow solid, whichappears to soften, though not to liquefy, at the temperature ofboiling water. This substance is readily soluble in hot solution ofpotash or soda, producing a deep brown liquid, from which it is againdeposited in flocks on acidifying. I have not yet found any solventfor it. The action of nitric acid with linseed oil is more similar tothis than that with any other oil I have tried, but the nitro productsof the two, if I may so call them, are quite different from oneanother. That from linseed oil produced as indicated remains liquid atordinary temperatures, as does the oil upon its addition to the acid. 

_Elaidin Test. _--By the action of nitric acid in presence of mercury, a semi-solid mass is produced of a much deeper color than in thepreceding cases. A portion of the oil remains in the liquid state, asis usually the case with drying oils. 

_Free Acidity. _--By the method indicated, it was found that 100grammes of oil required 0. 39 grammes caustic potash to neutralize theacid occurring in a free state. 

_Saponification of the Oil. _--The oil saponifies readily on beingheated with potash in presence of alcohol, and the amount required toconvert it entirely into potash soap was 211 grammes of caustic potashper thousand grammes of oil. There are no saponification numbers foroils that can be considered close to this. I can find no record ofany having been obtained between 197 and 221, so that the furtherexamination on which I am now engaged may show this unusual number tobe due to this oil containing some new fatty acid in combination. 

_The Fatty Acid. _--The acids produced by adding acid to the potashsoap formed in this case a cake on cooling, of a much deeper colorthan I have before obtained. After washing well they amounted to 94. 10per cent. Of the oil. The amount dissolved by the water in washingwas in this case also very small, the potash required for neutralizingequaling 1. 02 per cent. Of the weight of oil. 

I found that the cakes of acids were solid at 36° C. , and werecompletely melted at 39°. 

On solution in alcohol, and digestion for two days with animalcharcoal, the color was much diminished, and on the liquid beingfiltered and cooled to 0° C. , an abundance of small white crystallineplates separated out, which, when dried, melted at 67° C. 

The crude fatty acids turn black with sulphuric acid, as the oildoes, and yield a similar substance with nitric acid. It is similarin appearance, but differs in that it melts at about 50° C. , andis soluble in glacial acetic acid, which is not the case with thesubstance from the oil. 

These fatty acids crystallize on cooling, in a most characteristic andbeautiful way, forming wavy circular plates totally unlike any that Ihave seen before. 

The above experiments may, I think, be taken as conclusive as tothe nature of tea oil and cabbage oil. The former may certainlybe considered a useful lubricating agent for the finer kinds ofmachinery. The work upon wood oil is not yet sufficiently complete toshow us the nature of its proximate constituents. I am continuing theexamination of this oil. Perhaps I need scarcely add that there is noconnection between this "wood oil" and the Gurgun balsam, the productof _Dipterocarpus turbinatus_, which is also known as "wood oil. "

 * * * * *

THE OTOSCOPE. 

Prof. Leon Le Fort has recently presented to the Academy of Medicine, in the name of Dr. Rattel, a new otoscope, which we illustrateherewith. 

The first person to whom the idea occurred to illuminate the ear wasFabricius d'Acquapendentus (1600). To do this he placed the patient infront of a window in such a way as to cause the luminous rays to enterthe external auditory canal. It was he likewise who conceived theidea of placing a light behind a bottle filled with water, and ofprojecting its concentrated rays into the ear. 

In 1585 Fabricius de Hilden invented the speculum auris. Thisinstrument was employed by him for the first time under the followingcircumstances: A girl ten years of age had in playing introduceda small glass ball into her left ear, and four surgeons, called insuccessively and at different times, had been unable to extractit. Meanwhile the little patient was suffering from an earache thatextended over almost the entire head, and that increased at nightand especially in cold and damp weather. To these symptoms wereadded strokes of epilepsy and an atrophy of the left arm. Finally, inNovember, 1595, De Hilden, being called in, acquainted himself withthe cause of the trouble, and decided to remove the foreign body. Todo this, he selected, as he tells us, "a well lighted place, causedthe solar light to enter the ailing ear, lubricated the sides of theauditory canal with oil of almonds, and introduced his apparatus. "Then, passing a scoop with some violence between the side of theauditory canal and the glass ball, he succeeded in extracting thelatter. 

At the beginning of the 17th century, then, physicians had at theirdisposal all that was necessary for making an examination of the ear, viz. : (1) a luminous source; (2) a means of concentrating the light;and (3) an instrument which, entering the auditory canal, held itssides apart. 

The improvements which succeeded were connected with each of thesethree points. To solar light, an artificial one has been preferred. D'Acquapendentus' bottle has given way to the convex lens, and toconcave, spherical, and parabolic mirrors, etc. De Hilden's speculumhas been replaced by cylindrical, conical, bivalve, and other forms ofthe instrument. 

The apparatus that we illustrate herewith offers some arrangementsthat are all its own as regards the process of concentrating thelight. It is lighted, in fact, by a small incandescent lamp of2 candle-power, placed within the apparatus and supplied by anaccumulator. The reflector is represented by a portion of an ellipseso calculated that one of the foci corresponds to the lamp and theother to the extremity of the instrument. A commutator, B, permits ofestablishing or interrupting the current at will. A rheostat addedto the accumulator makes it possible to graduate the light at one'sleisure and cause it to pass through all the shades comprised betweencherry-red and incandescence. Finally, the orifice through which theobserver looks is of such dimensions that it gives passage to allthe instruments necessary for treating complaints of the middle andinternal ear. 

[Illustration: RATTEL'S OTOSCOPE. ]

This mode of lighting and reflection may be adapted to a Bruntonotoscope, utilized for examining other natural cavities, such as thenose, pharynx, etc. Elliptical reflectors do not appear to have beenemployed up to the present. 

 * * * * *

STATE PROVISION FOR THE INSANE. [1]

 [Footnote 1: Remarks following "Definition of Insanity, " published in the October number of _The Alienist and Neurologist_, and read before the Association of Charities and Corrections at St. Louis, Oct. 15, 1884. ]

By C. H. HUGHES, M. D. 

We live in an age when every uttered sentiment of charity toward theinsane is applauded to its remotest echo; an age in which the chainsand locks and bars and dismal dungeon cells and flagellations andmanifold tortures of the less humane and less enlightened past arejustly abhorrent; an age which measures its magnificent philanthropyby munificent millions, bestowed without stint upon monumentalmansions for the indwelling of the most pitiable and afflicted of thechildren of men, safe from the pitiless storms of adverse environmentwithout which are so harshly violent to the morbidly sensitive andunstable insane mind; an age in which he who strikes a needlessshackle from human form or heart, or removes a cause of human torture, psychical or physical, is regarded as a greater moral hero than hewho, by storm or strategy of war taketh a resisting fortress; an agewhen the Chiarugis and Pinels, the Yorks and Tukes, of not remotelypast history, and the Florence Nightingales and Dorothea Dixes of ourown time, are enshrined in the hearts of a philanthropic world withgreater than monumental memory. 

Noble, Christlike sentiment of human charity! Let it be cherished andfostered still, toward the least of the children of affliction andmisfortune, as man in his immortal aspirations moves nearer andnearer to the loving, charitable heart of God, imaging in his work theexample of the divinely incarnate Master!

But let us always couple this exalted sentimentality with the sternlogic of fact, and never misdirect or misapply it in any of ourcharitable work. Imperfect knowledge perverts the noblest sentiments;widened and perfected knowledge strengthens their power. A trulyphilanthropic sentiment is most potent for good in the powerof knowledge, and may be made most powerful for evil throughmisconception of or inadequate comprehension of facts. As we grow inaspirations after the highest welfare of the insane, let us _widen ourknowledge of the real nature of insanity and the necessities for itsamelioration, prevention, and cure_. 

It is a long time since Grotius wrote, "The study of the human mind isthe noblest branch of medicine;" and we realize to-day that it isthe noblest study of man, regardless of vocation. Aye! it is theimperative study of our generation and of those who are to follow us, if we would continue, as we wish to be, the conservators of the goodand great, and promoters of advancing capability for great and gooddeeds in our humanity. 

One known and acknowledged insane person to every five hundred sanepersons, and among those are unreckoned numbers of unstably endowedand too mildly mannered lunatics to require public restraint, but nonethe less dangerous to the perpetuation of the mental stability of therace, is an appalling picture of fact for philanthropic conservatorsof the race to contemplate. 

The insane temperament and its pathological twin brother, theneuropathic diathesis, roams at large unrestrained from without orthat self-restraint which, bred of adequate self-knowledge, might comefrom within, and contaminates with neurotic and mental instability theinnocent unborn, furnishing histogenic factors which the future willformulate in minds dethroned to become helpless wards of the state orfamily. 

The insane temperament is more enduringly fatal to the welfare ofhumanity than the deadly _comma bacillus_ which is supposed to conveythe scourge of Asia to our shores. The latter comes at stated periods, and disappears after a season or two of devastation, in which theleast fit to survive of our population, by reason of feeble organicresisting power, are destroyed; while resisting tolerance isestablished in the remainder. But _this_ scourge is with us always, transmitting weakness unto coming generations. 

It is the insanity in chronic form which escapes asylum care andcustody except in its exacerbations; it is the insanity of organismwhich gives so much of the erratic and unstable to society, in itsmanifestations of mind and morals; it is the form of unstable mentalorganism which, like an unstrung instrument jangling out of tune andharsh, when touched in a manner to elicit in men of stable organismsonly concord of sweet, harmonious sounds; it is the form of mentalorganism out of which, by slight exciting causes largely imaginary, the Guiteaus and Joan d'Arcs of history are made, the Hawisons andPassanantis and Freemans, and names innumerable, whose deeds ofblood have stained the pages of history, and whose doings in our daycontribute so largely to the awful calendar of crime which blackensand spreads with gore the pages of our public press. 

We may cherish the sentiment that it were base cowardice to lay handupon the lunatic save in kindness; and yet restrain him from himselfand the community from him. We may couple his restraints with thelargest liberty compatible with his welfare and ours; we may notalways abolish the bolts and bars, indeed we cannot, either to hisabsolute personal liberty in asylums or to his entire moral freedomwithout their walls, yet we may keep them largely out of sight. Lethim be _manacled when he must and only when he must_, and then onlywith silken cords bound by affectionate hands, and not by chains. We may not open all the doors, indeed we cannot, but we can and do, thanks to the humanitarian spirit of the age in which we live, openmany of them and so shut them, when it must need be done, that theyclose for _his_ welfare and ours only; that he may not feel that hopeis gone or humanity barred out with the shutting of the door thatseparates him from the world. 

We may not always swing the door of the lunatic as facilely outward asinward--the nature of his malady will not always admit of this--but weshould do it whenever we can, and never, when we must, should weclose it harshly. And while we must needs narrow his liberty amongourselves, we should enlarge it in the community to which hisaffliction assigns him, to the fullest extent permissible by thenature of his malady. 

Liberty need not necessarily be denied him; and to the glory of ourage it is not in the majority of American asylums for the insane, because the conditions under which he may safely enjoy liberty, tohis own and the community's welfare, are changed by disease. The freesunlight and the fresh air belong as much to him in his changed mentalestate as to you or me, and more, because his affliction needs theirinvigorating power, and the man who would chain, in this enlightenedage, an insane man in a dungeon, because he is diseased andtroublesome or dangerous, would be unworthy the name of human. Effective restraint may be employed without the use of either ironmanacles or dismal light and air excluding dungeons. 

The insane man is one of our comrades who has fallen mentally maimedin the battle of life. It may be our turn next to follow him to therear; but because we must carry him from the battlefield, where he mayhave fought even more valiantly than ourselves, we need not forget orneglect him. The duty is all the more imperative that we care for him, and in such a manner that he may, if possible, be restored. Simplesequestration of the insane man is an outrage upon him and upon ourhumanity. "Whatsoever ye would that men should do unto you, do yeeven so to them, " is the divine precept, which, if we follow it aswe ought, will lead us to search for our fallen comrades in thealms-houses and penal institutions and reformatories, and sometimes inthe outhouses or cellars of private homes, to our shame, where errorsof judgment or cruelty have placed them, and to transfer them toplaces of larger liberty and hopes of happiness and recovery. Thechronic insane are entitled to our care, not to our neglect, and toall the comforts they earned while battling with us, when in theirbest mental estate, for their common welfare and ours. 

Almshouses and neglected outhouses are not proper places for them. They are entitled to our protection and to be so cared for, if wecannot cure them, as that they may not do those things, to their ownharm or the harm of the race, which they would not do if they weresound in mind. Society must be protected against the spread ofhereditary insanity, hence such kindly surveillance, coupled with thelargest possible liberty, should be exercised over them as will saveposterity, so far as practicable, from the entailment of a heritagemore fatal than cancer or consumption. 

The insane man is a changed man, and his life is more or lessdelusional. In view of this fact, we should endeavor always to sosurround him that his environments may not augment the morbid changein him and intensify his perverted, delusioned character. 

Realizing the fact that mind in insanity is rather perverted thanlost, we should so deport ourselves toward the victims of this diseaseas in no wise to intensify or augment the malady, but always, ifpossible, so as to ameliorate or remove it. 

Realizing that the insane man in his best estate may have walked theearth a king, and in this free country of ours have been an honoredsovereign weighted with the welfare of his people, and contributing ofhis substance toward our charities, we should, with unstinting hand, cater to his comfort when this affliction comes upon him. 

We should give him a home worthy of our own sovereign selves, and suchas would suit us were we providing for ourselves, with the knowledgewe have of the needs of this affliction, pending its approach to us. 

That his home should be as unirritating and restful to him as possibleit should be unprison-like always, and only be an imprisonment whenthe violent phases of his malady imperatively demand restraint. An hour of maniacal excitement does not justify a month of chains. Mechanical restraint is a remedy of easy resort, but the fetteredman frets away strength essential to his recovery. Outside of asylumsdirect restraint is often a stern necessity. It is sometimes so inthem, but in many of them and outside of all of them it may be greatlydiminished, and asylums may be so constructed as to make the reductionof direct restraint practicable to the smallest minimum. Directmechanical restraint for the insane, save to avert an act of violencenot otherwise preventable, is never justifiable. The hand should neverbe manacled if the head can be so influenced as to stay it, and weshould try to stay the hand through steadying the head. 

Every place for these unfortunates should provide for them ample roomand congenial employment, whether profitable to the State or not, andthe labor should be induced, not enforced, and always timed and suitedto their malady. A variety of interesting occupations tends to divertfrom delusional introspection. 

Most institutions attempt to give their patients some occupation, butState policy should be liberal in this direction. 

Deductions are obvious: Every insane community of mixed recent andlong standing cases, or of chronic cases exclusively, should be ahome, and not a mere place of detention. It should be as unprison-likeand attractive as any residence for the non-criminal. It should havefor any considerable number of insane persons at least a section(640 acres) of ground. It should be in the country, of course, butaccessible to the supplies of a large city. It should have a centralmain building, as architecturally beautiful and substantial as theState may choose to make it, provided with places of security for suchas require them in times of excitement, with a chapel, amusement hall, and hospital in easy covered reach of the feeble and decrepit, andaccessible, without risk to health, in bad weather. 

Outhouses should be built with rooms attached, and set apart from theresidence of trustworthy patients, for farmer, gardener, dairyman, herdsman, shepherd, and engineer, that those who desired to beemployed with them, and might safely be intrusted, and were physicallyable, could have opportunity of work. 

Cottages should be scattered about the ground for the use and benefitof such as might enjoy a segregate life, which could be used forisolation in case of epidemic visitation. Recreation, games, drives, and walks should be liberally provided. 

A perfect, but not direct and offensive, surveillance should beexercised over all the patients, with a view to securing them thelargest possible liberty compatible with the singular nature of theirmalady. 

In short, the hospital home for the chronic insane, or when acute andchronic insane are domiciled together, should be a colonial home, withthe living arrangements as nearly those which would be most congenialto a large body of sane people as the condition of the insane, changedby disease, will allow. 

It is as obvious as that experience demonstrates it, that the reigninghead or heads of such a community should be medical, and notthat medical mediocrity either which covets and accepts politicalpreferment without medical qualifications. 

The largest personal liberty to the chronic insane may be best securedto them by provision for the sexes in widely separated establishments. 

It is plain that the whole duty of man is not discharged toward hisfallen insane brother when he has accomplished his sequestration fromsociety at large, or fed and housed him well. The study of the needsof the insane and of the duty of the State in regard to them is asimportant and imperative a study as any subject of political economy. 

 * * * * *

THE COURAGE OF ORIGINALITY. 

Most of us are at times conscious of hearing from the lips ofanother, or reading from the printed page, thoughts that have existedpreviously in our own minds. They may have been vague and unarranged, but still they were our own, and we recognize them as old friends, though dressed in a more fitting and expressive costume than we evergave them. Sometimes an invention or a discovery dawns upon the worldto bless and improve it, and while all are engaged in extolling itsome persons feel that they have had its germs floating in theirminds, though from the lack of favorable conditions, or some othercause, they never took root or became vital. An act of heroism isperformed, and a bystander is conscious that he has that within him bywhich he could have taken the same step, although he did not. Some onesteps forward and practically opposes a social custom that is admittedto be evil, yet maintained, and by his influence lays the ax toits root and commences its destruction; while many, commending hiscourage, wonder why they had not taken the same course long ago. In numberless instances we are conscious of having had the sameperceptions, the same ideas, the same powers, and the same desiresto put them into practice that are shown by the one who has sosuccessfully expressed them; yet they have, for some reason, laindormant and inoperative within us. 

When we consider the waste of human power that this involves, we maywell search for its cause. Doubtless it sometimes results from theabsorption (more or less needful) of each one is his individualpursuit. No one can give voice to all he thinks, or accomplish allthat he sees to be desirable, while striving, as he should, to gainexcellence in his own chosen work. Conscious of his own limitations, he will rejoice to see many of his vague ideas, hopes, and aspirationsreached and carried out by others. But the same consciousness thatreconciles him to this also reveals much that he _might_ have said ordone without violating any other obligation, but which he has allowedto slip from his hands to those of another, perhaps through lack ofenergy, or indolence, or procrastination. The cause, however, mostoperative in this direction is a strange disloyalty to our ownconvictions. We look to others, especially to what we call great men, for thoughts, suggestions, and opinions, and gladly adopt themon their authority. But our own thoughts we ignore or treat withindifference. We admire and honor originality in others, but we valueit not in ourselves. On the contrary, we are satisfied to make poorimitations of those we revere, missing the only resemblance that isworth anything, that of a simple and sincere independent life. 

We would not undervalue modesty or recommend self-sufficiency. Weshould always be learners, gladly welcoming every help, and respectingevery personality. But we should also respect our own, and bear inmind, that "though the wide universe is full of good, no kernel ofnourishing corn can come to us but through our toil bestowed on thatplot of ground which is given to us to till. " To undervalue our ownthought because it is ours, to depreciate our own powers or facultiesbecause some one else's are more vigorous, to shrink from doing whatwe can because we think we can do so little, is to hinder our owndevelopment and the progress of the world. For it is only by exercisethat any faculty is strengthened, and only by each one putting hisshoulder to the wheel that the world moves and humanity advances. 

There is nothing more insidious than the spirit of conformity, andnothing more quickly paralyzes the best parts of a man. A gleam oftruth illuminates his mind, and forthwith he proceeds to compare itwith the prevailing tone of his community or his set. If it agree notwith that, he distrusts and perhaps disowns it; it is left to perish, and he to that extent perishes with it. By and by, when some one moreindependent, more truth-loving, more courageous than himself arisesto proclaim and urge the same thing that he was half ashamed toacknowledge, he will regret his inglorious fear of being in theminority. We are accustomed to think that greatness always denotesexceptional powers, yet most of the world's great men have rather beendistinguished by an invincible determination to work out the bestthat was within them. They have acted, spoken, or thought according totheir own natures and judgment, without any wavering hesitation as tothe probable verdict of the world. They were loyal to the truth thatwas in them, and had faith in its ultimate triumph; they had a missionto fulfill, and it did not occur to them to pause or to falter. Howmany more great men should we have were this spirit universal, and howmuch greater would each one of us be if, in a simple straightforwardmanner, we frankly said and did the best that we knew, without fear orfavor? Soon would be found gifts that none had dreamed of, powers thatnone had imagined, and heroism that was thought impossible. As Emersonwell says, "He who knows that power is inborn, that he is weak becausehe has looked for good out of him and elsewhere, and so perceivingthrows himself unhesitatingly on his thought, instantly rightshimself, stands in the erect position, commands his limbs, worksmiracles, just as a man who stands on his feet is stronger than a manwho stands on his head. "--_Phil. Ledger. _

 * * * * *

A CIRCULAR BOWLING ALLEY. 

The arcades under the elevated railroad which runs transverselythrough Berlin are used as storehouses, stores, saloons, restaurants, etc. , and are a source of considerable income to the railway company. The owner of one of the restaurants in the arcades decided to providehis place with a bowling alley, but found that he could not commandthe requisite length, 75 ft. , and so he had to arrange it in someother way. A civil engineer named Kiebitz constructed a circularbowling alley for him, which is shown in the annexed cut taken fromthe _Illustrirte Zeitung_. The alley is built in the shape of ahorse-shoe, and the bottom or bed on which the balls roll is hollowedout on a curved line, the outer edge of the bed being raised toprevent the balls from being thrown off the alley by centrifugalforce. 

[Illustration: A CIRCULAR BOWLING ALLEY. ]

The balls are rolled from one end of the alley, describe a curvedline, and then strike the pins placed at the opposite end of thealley. No return track for the balls is required, and all that isnecessary is to roll the balls from one end of the alley to the other. A recording slate, the tables for the guests, etc. , are arrangedbetween the two shanks or legs of the alley. 

It is evident that a person cannot play as accurately on an alley ofthis kind as on a straight alley; but if a ball is thrown with moreor less force, it will roll along the inner or outer edge of thealley and strike the group of pins a greater or less distance from themiddle. A room 36 ft. In length is of sufficient size for one of thesealleys. 

 * * * * *

PATENT OFFICE EXAMINATION OF INVENTIONS. 

_To the Editor of the Scientific American:_

It is with considerable surprise that the writer has just perusedthe editorial article in your issue of March the 28th--"Patent OfficeExaminations of Novelty of Inventions" It seems to me that theground taken therein is diametrically opposed to the views heretoforepromulgated in your journal on this subject, and no less so tothe interests of American inventors; and it appears difficult tounderstand why the abolition of examinations for novelty by the PatentOffice should be recommended in face of the fact that the acknowledgedsmall fees now exacted from inventors are sufficient to provide amuch greater force of examiners than are now employed on that work. If inventors were asking the government to appropriate money for thispurpose, the case would be quite different; although it may be shown, I think, that Congress would be fully justified in disposing of noinconsiderable portion of the public money in this way, should it everbecome necessary. 

Recognizing the fact that the patent records of all countries, as wellas cognate publications, are rapidly on the increase--and particularlyin this country--making an examination for novelty a continuouslyincreasing task, and that the time must come when such an examinationcannot be made at all conclusively without a vastly increased amountof labor, from the very magnitude of the operation, it is neverthelesstrue that this difficulty menaces the inventor to a much greaterextent, if imposed upon him to make, than it can ever possibly do aninstitution like the Patent Office. 

Dividing and subdividing patent subjects into classes and sub-classes, and systematizing examinations to the extent it may be made to reachin the Patent Office, may, for a very long time to come, place thismatter within the possibility of a reasonably good and conclusivesearch being made without additional cost to the inventor, providedwhat he now pays is all devoted to the furtherance of the PatentOffice business. If, however, we hereafter make no examinations fornovelty, an inventor is obliged to either make such a search forhimself--with all the disadvantages of unfamiliarity with the bestmethods, inaccessibility to records, and incurring immensely more workthan is required of the Patent Office examiner, who has everythingpertaining thereto at his fingers' ends--or blindly pay his fees andtake his patent under the impression that he is the first inventor, and run every risk of being beaten in the courts should any oneessay to contest his claims; the probabilities of his being so beatenincreasing in proportion as the number of inventions increase. 

The inventor pays to have this work done for him at the Patent Officein the only feasible way it can be thoroughly done; and the averageinventor would, or should, be willing to have the present fees verylargely increased, if necessary, rather than have the examinationsfor novelty abolished at the Patent Office; for, in the event of theirabolition, it would cost him immensely more money to secure himself, as before the courts, by his own unaided and best attainable methods. 

The inventor now, however, pays to the Patent Office, as you wellknow, a good deal more money every year than the present cost ofexaminations, including of course all other Patent Office business;seeing a part of what he pays yearly covered into the Treasury assurplus, while his application is unreasonably delayed for the lack ofexaminer force in the Patent Office. 

Let the government first apply all the moneys received at the PatentOffice to its legitimate purpose, including the making of theseexaminations, and, when this proves insufficient, you may dependthat every inventor will cheerfully consent to the increase of fees, sufficient to insure the continuance of thorough examinations fornovelty, rather than attempt to do this work himself or take thechances of his having reinvented some old device (which it is verywell known occurs over and over again every day), and being beatenupon the very first contest in the courts, after, perhaps, investinglarge amounts of money, time, and anxiety over something which he thusdiscovers was invented, perhaps, before he was born. 

For an inventor to obtain a patent worth having, and one that isnot more likely to be a source of expenditure than income to him, ifcontested, it goes without saying that examination for novelty mustbe made either by himself or some competent person or persons for him;and it is strictly proper and just that the inventor should pay forit; and it is too self-evident a proposition to admit of argument thatthe organized and systematized methods of the Patent Office can do itat a tithe of the expense which would be incurred in doing it in anyother way; in point of fact, it would be impossible to do it by anyother means so effectually or so well within any reasonable amount ofcost. 

Your summing up of the case should, instead of the way you put it, read: The Commissioner of Patents attempts to perform for two-thirdsthe sum paid as fees by inventors what he is paid three-thirds toaccomplish, so that one-third of it may go to swell the surplus ofthe United States Treasury, and finds it an impracticable task toascertain the novelty of an invention in a reasonable time for such asum. To perform it, however imperfectly, he feels authorized to delaythe granting; of patents, sometimes for several months, simply becauseCongress will not allow him to apply the moneys paid by inventors totheir legitimate purpose. 

I have had, for several years, always more or less applications onfile at the Patent Office for inventions in my particular line, andnow have several pending; and probably there are few, if any, whohave suffered more from the great delays lately obtaining at thatinstitution than myself, particularly in connection with taking outforeign patents for the same inventions, and so timing the issue ofthem here and abroad as not to prejudice either one. But great as theannoyance and cost have been in consequence of these delays, I wouldinfinitely prefer that it were ten times as great, rather than see theexaminations for novelty abolished by the United States PatentOffice; and, so far as I know and believe, in this preference I mostcompletely voice that of inventors in general. 

 JOHN T. HAWKINS. Taunton, Mass. , March 28th, 1885. 

The writer of the above communication gives a very clear statement ofour original premises. He sees as we do the difficulty, every yearon the increase, of making satisfactory searches in the matter ofnovelty. But his deductions vary from ours. To us it appears on itsface an impossibility for satisfactory searches to be made in the caseof every individual patent by the Patent Office. The examinationshave repeatedly been proved valueless. We know by our own andothers' experience that the searches as at present conducted are ofcomparatively little accuracy. Patents are declared to be anticipatedcontinually by our courts. The awarding of a patent in fact weighs fornothing in a judge's mind as proving its originality. The Commissionerof Patents is really exhausting the energies of the Office employeesover a multitude of searches that have no standing whatever incourt, and that no lawyer would accept as any guarantee of noveltyof invention. If every inventor would search the records for his ownbenefit, we should then have twenty thousand examiners instead of thepresent small number. This would be something. But if it be advancedthat the inventor is not a competent searcher, then he can engage anexpert to do it for him. Every day, searches of equal value to thePatent Office ones are executed for but a fraction of the governmentfees on granting a patent. 

Our correspondent speaks of an evil that he thinks would be incidentalto the system we proposed in our article criticised by him, namely, that were the Patent Office to make no search an inventor would "runevery risk of being beaten in the courts should any one essayto contest his claims. " The fact is that in spite of the Officeexamination for novelty this risk always has to be encountered, and forms a criterion by which to judge of the exact value of thatexamination. Furthermore, we take decided issue with our correspondentwhen he says that the present is the only feasible way of executingthese searches thoroughly. They are not so executed as a matter offact, and could be done better and cheaper by private individuals, experts, or lawyers, engaged for the purpose by inventors. 

We agree that all money received by the Patent Office should beapplied to its legitimate end. It seems to us a great injustice tomake one generation of patentees accumulate money in the Treasury forthe benefit of some coming generation. Application of the whole ofeach year's fees to the expediting of that year's business would besimple justice. But we do not lose sight of our main point, that werethe inventor unable to make a satisfactory search, it could be donefor him by private parties better and cheaper than it is now done inthe Office. 

We are very glad to have the question so intelligently discussed asby our correspondent, and we feel that it is one well worthy ofconsideration. The future will, we are sure, bring about some change, by which inventors will be induced to bestow more personal care ontheir patents, at least to the extent of securing searches for noveltyto be made by their own attorneys, and even at a little additionalexpense to abandon any blind dependence on the Patent Office as aprover of novelty. --Ed. Sc. Am. 

 * * * * *

THE UNIVERSAL EXPOSITION AT ANTWERP (ANVERS), BELGIUM. 

Never before was there so striking and remarkable an example of whatcan be accomplished by private enterprise when applied to a great anduseful object. Last year some prominent citizens of Antwerp--justlyproud of the rapid and marvelous progress made by theircity--conceived the idea of inviting the civilized world to come andadmire the transformation which, in half a century, had converted thecommercial metropolis of Belgium into the first port of the Europeancontinent. This audacious project has been carried into execution, and the buildings of the Universal Exposition, including the Hall ofIndustry, the Gallery of Machinery, and the innumerable annexes, cover2, 368, 055 sq. Ft. Of ground. Even this large space has proved toolimited. These buildings are shown in the accompanying cut. 

All nations have responded to the call of the citizens of Antwerp, who are supported by the patronage of a sovereign devoted to progress, Leopold II. , King of the Belgians. Among the countries representedin the exposition, France takes the first rank. She is representedby over 2, 000 exhibits, and her products occupy one-fifth part of theHall of Industry and the Gallery of Machinery. The pavilion of theFrench Colonies is an exact representation of a palace of CochinChina. 

Belgium is represented by 2, 400 exhibits. The French and Belgiancompartments together occupy one-half of the Hall of Industry andthe Gallery of Machinery. This latter building represents agrand spectacle, especially in the evening, when it is lighted byelectricity. In excavating under this gallery, ruins were brought tolight which proved to be the foundations of the citadel of the Duked'Albe, the terrible lieutenant of Philip II. Of Spain. Thus, on thesame site where once stood this monument of oppression and torture, electricity, that bright star of modern times, will illuminate themost wonderful inventions of human progress. --_L'Illustration. _

[Illustration: BIRD'S-EYE VIEW OF THE UNIVERSAL EXPOSITION ATD'ANVERS, BELGIUM. ]

 * * * * *

THE STONE PINE. 

(PINUS PINEA. )

Although not such an important tree in this country as many otherconifers, the Stone pine possesses a peculiar interest beyond that ofany other European conifer. From the earliest periods it has been thetheme of classical writers. Ovid and Pliny describe it; Virgilalludes to it as a most beautiful ornament; and Horace mentions apine agreeing in character with the Stone pine; while in Pompeiiand Herculaneum we find figures of pine cones in drawings and on thearabesques; and even kernels of charred pines have been discovered. The Pinaster of the ancients does not appear to be the same as that ofthe moderns; the former was said to be of extraordinary height, whilethe latter is almost as low as the Stone pine. No forest is fraughtwith more poetical and classical interest than the pine wood ofRavenna, the glories of which have been especially sung by Dante, Boccacio, Dryden and Byron, and it is still known as the "Vicolo de'Poeti. "

The Stone pine is found in a wild state on the sandy coasts and hillsof Tuscany, to the west of the Apennines, and on the hills of Genoa, usually accompanied by, and frequently forming forests with, the Pinuspinaster. It is generally cultivated throughout the whole of Italy, from the foot of the Alps to Sicily. It is not commonly found higherthan from 1, 000 feet to 1, 500 feet, but it occurs in the south ofItaly as high as 2, 000 feet. It is found, according to Sibthorp, onthe sandy coasts of the Western Peloponnesus, in the same conditions, probably, as in the middle of Italy; it is also met with in theisland of Melida. Cultivated, it is found on all the shores of theMediterranean. In northern Europe, and especially in England, itsgeneral appearance is certainly that of a low-growing tree, itsdensely clothed branches forming almost a spherical mass; but in thesunny south it attains a height of 75 feet to 100 feet, losing, as itascends, all its branches, except those toward the summit, which, inmaturity, assume a mushroom form. 

Seen in the soft clime of Italy in all its native vigor, the Stonepine is always majestic and strangely impressive to a northern eye, whether in dense forests, as near Florence, in more open masses, as atRavenna, in picturesque groups, as about Rome, or in occasional singletrees, such as may be seen throughout the country, but rather morefrequently toward the coast. In these isolated trees their imposingcharacter can be best appreciated, the great trunk carrying themassive head perfectly poised, an interesting example of ponderousweight gracefully balanced. The solid, weighty appearance of thehead of the tree is increased by its even and generally symmetricaloutline, this especially in the examples near the coast, the mass offoliage being so close and dense that it looks like velvet, and incolor a warm rich olive green, strangely different from the bluegreens and black greens of our northern pines. The lofty or normaltype with the umbrella-formed top is almost peculiar to Central andSouthern Italy. In other parts of the south of Europe, though oftenattaining large dimensions, it remains more dwarf and rotund in shape. 

[Illustration: THE STONE PINE (PINUS PINEA) AT CASTEL GANDOLFO, INITALY. ]

This pine has not been much planted in this country, owing, nodoubt, to its slow growth and want of hardiness in a young state. Consequently there are not many large specimens, and certainly none tocompare with those of Italy for size or picturesque beauty. Mr. A. D. Webster, the forester at Penrhyn Castle, North Wales, who has kindlysent us a fine cone of this pine, writes thus respecting it: "Afair-sized specimen of this pine stands on the sloping ground to thesouthwest of Penrhyn Castle. It shows off to advantage the peculiaroutline of this pine, which is so marked a characteristic of thosegrown in the Mediterranean region. The trunk, which is about 4½ feetin girth at a yard up, rises for three-fourths its height withoutbranches, after which it divides into a number of limbs, theextremities of which are well covered with foliage, thus giving tothe tree a bushy, well-formed, and, I might almost add, roundedappearance. At a casual glance the whole tree might readily bemistaken for the pinaster, but the leaves are shorter, less tufted, and always more erect. The bark of the Stone pine is somewhat roughand uneven, of a dull gray color, unless between the furrows, which isof a bright brown. That on the branches is more smooth and of alight reddish brown color. When closely examined, there is somethingremarkably pleasing and distinct from the generality of pines in theappearance of this tree, the leaves, which are of a deep olive-green, being, from their regularity and usual closeness, when seen in goodlight, like the finest network. "

There is a moderately large specimen in the arboretum at Kew, and ifthis is the tree which Loudon in his "Arboretum" alluded to as a "merebush, " it has made good growth during the past thirty years. Accordingto Veitch's "Manual of Coniferæ, " a fine specimen, one of the largestin the country, is at Glenthorn, in North Devon. It is 33 feet high, and has a spread of branches some 22 feet, while the trunk is clearof branches for 15 feet. Loudon enumerates several fine trees in theseislands at that date (1854), only one of which was 45 feet high. Thisone was at Ballyleady, in County Down, and had been planted about 60years. Even where planted in the most favored localities, we can neverexpect the Stone pine to assume its true character, and that is thereason why so few plant it. 

As a timber tree it is of not much value. Mr. Webster says, "The woodis worthless except for very ordinary purposes. The timber grownhere (Penrhyn) is, from the few specimens I have had the chance ofexamining, very clean, light, from the small quantity of resin itcontains, and in color very nearly approaches the yellow pineof commerce. It cuts clean and works well under the tools ofthe carpenter. In its native country the wood has been used forboat-building, but is now, I believe, almost entirely discarded. " Thispine thrives best on a soil that is deep, sandy, and dry. It should bewell sheltered and nursed, as it is rather tender while in its youngstate. It is best to keep the seedlings under glass, though they maybe planted out in the open air after their fourth or fifth year. 

The cones of this pine supply the "pignoli" of commerce. The Italiancooks use these seeds in their soups and ragouts, and in the Maritozzibuns of Rome. Sometimes the Italians roast the barely ripe cone, dashing it on the ground to break it open, but the ripe seeds of theolder cone when it naturally opens are better worth eating. They aresoft and rich, and have a slightly resinous flavor. The empty conesare used by the Italians for fire lighting, and being full of resinousmatter they burn rapidly and emit a delightful fragrance. 

_Description. _--Pinus pinea belongs to the Pinaster section of thegenus. In the south of Europe it is a lofty tree, with a spreadinghead forming a kind of parasol, and a trunk 50 feet or 60 feet high, clear of branches. The bark of the trunk is reddish and sometimescracked, but the general surface of the bark is smooth except onthe smaller branches, where it long retains the marks of the fallenleaves, in the shape of bristly scales. The leaves are of a dullgreen, but not quite so dark as those of the Pinaster; they aresemi-cylindrical, 6 inches or 7 inches long and one-twelfth of an inchbroad, two in a sheath, and disposed in such a manner as to form atriple spiral round the branches. 

The catkins of the male flowers are yellowish; and being placed onslender shoots of the current year, near the extremity, twenty orthirty together, they form bundles, surmounted by some scarcelydeveloped leaves. Each catkin is not more than half an inch long, on avery short peduncle, and with a rounded denticulated crest. The femalecatkins are whitish, and are situated two or three together, at theextremity of the strongest and most vigorous shoots. Each femalecatkin has a separate peduncle, charged with reddish, scarious, lanceolate scales, and is surrounded at its base with a double row ofthe same scales, which served to envelop it before it expanded; itsform is perfectly oval, and its total length about half an inch. The scales which form the female catkin are of a whitish green; thebractea on the back is slightly reddish on its upper side; and thestigma, which has two points, is of a bright red. After fertilization, the scales augment in thickness; and, becoming firmly pressed againsteach other, they form by their aggregation a fruit, which is threeyears before it ripens. During the first year it is scarcely largerthan the female catkin; and during the second year it becomesglobular, and about the size of a walnut. The third year the conesincrease rapidly in size; the scales lose their reddish tinge, andbecome of a beautiful green, the point alone remaining red; and atlast, about the end of the third year, they attain maturity. Atthis period the cones are about four inches long and three inches indiameter, and they have assumed a general reddish hue. The convexpart of the scales forms a depressed pyramid, with rounded angles, thesummit of which is umbilical. Each scale is hollow at its base; and inits interior are two cavities, each containing a seed much larger thanthat of any other kind of European pine, but the wing of which is, onthe contrary, much shorter. The woody shell which envelops the kernelis hard and difficult to break in the common kind, but in the varietyfragilis it is tender, and easily broken by the fingers. In both thekernel is white, sweet, and agreeable to the taste. The taproot of thestone pine is nearly as strong as that of P. Pinaster; and, like thatspecies, the trees, when transplanted, generally lean to one side, from the head not being correctly balanced. Hence, in full-grown treesof the Stone pine there is often a similar curvature at the base ofthe trunk to that of the pinaster. The palmate form of the cotyledonsof the genus Pinus is particularly conspicuous in those of P. Pinea. When one of the ripe kernels is split in two, the cotyledons separate, so as to represent roughly the form of a hand; and this, in some partsof France, the country people call _la main de Dieu_, and believedto be a remedy in cases of intermittent fever if swallowed in unevennumbers, such as 3, 5, or 7. The duration of the tree is much greaterthan that of the pinaster, and the timber is whiter and somewhat moredurable. In the climate of London trees of from fifteen to twentyyears' growth produce cones. 

There are no well-marked varieties of the Stone pine, though in itsnative districts geographical forms may occur. For instance, Loudondescribes a variety cretica, which is said to have larger cones andmore slender leaves. Duhamel also describes a variety fragilis, havingthinner shells to the seeds or kernels. Neither of these varieties isin this country, so far as we are aware. There are various synonymsfor P. Pinea, the chief being P. Sativa of Bauhin, P. Aracanensisof Knight, P. Domestica, P. Chinensis of Knight, and P. Tarentina ofManetti. --_The Garden. _

 * * * * *

THE ART OF BREEDING. 

From a paper read by C. M. Winslow, Brandon, Vt. , before the AyrshireBreeders, at their annual meeting, in Boston, Feb. 4, 1885:

Sometimes we meet with breeders whose only aim in their stock seem tobe to produce animals that shall be entitled to registry. To such Ihave little to say, as their work is comparatively easy, and has butfew hindrances to success; but to those breeders who are possessed ofan ideal type of perfection, which they are striving to impress upontheir stock, I have a few words to say upon the hindrances they mayfind in the way of satisfactory results. It is a law of nature thatthe offspring resembles some one or more of its ancestors, not only inthe outward appearance, but in the construction of the vital organismand mental peculiarities, and is simply a reproduction, with theaccidental or intentional additions that from time to time areaccumulating as the stock passes through the hands of more or lessskillful breeders. 

The aim of the breeder is to not only produce an animal which shallin its own person possess the highest type of excellence sought, butshall have the power to transmit to its offspring those qualitiesof value possessed by himself. A breeder may, by chance, produce asuperior animal, or it may be the result of carefully laid plans andartfully controlling the forces of nature and subjecting them to hiswill. 

It is comparatively easy to accidentally produce an animal of value, but to steadily breed to one type is the test of the skill of thebreeder and the value of his stock. However well he may lay his plans, or however desirable his stock may appear, his ability to perpetuatetheir desirable qualities will depend upon the prepotence of theanimals, and this prepotence depends, to a great extent, upon thelength of the line in which the stock has been bred with one definiteend in view. A man may, in his efforts to breed stock excelling in acertain line, produce stock that shows excellence in other qualities, but this will not compensate for a deficiency in the qualification heis attempting to impress, nor is it safe to breed from any animal thatdoes not show, in a marked degree, those desired qualities. 

There is one qualification without which there can be no success, and that is a sound, healthy constitution, with good vital organs andvigorous digestion; and any amount of success in other directions willnot compensate for lack of constitution, and disappointment is alwayssure to attend the breeder who does not guard this, the foundation ofall success.... 

The very finest type of breeding and surest plans of success may beentirely defeated by improper feed and care. A valuable herd may beentirely ruined by a change of food and care; for those conditionswhich have conspired to produce a certain type must be continued, orthe type changes, it may be for the better or it may be for the worse, since stock very readily adapt themselves to their surroundings; andit is just here that so many are disappointed in buying blood stockfrom a successful breeder; for a successful breeder is necessarily agood feeder and a kind handler, and stock may give good results inhis hands, and, if removed to starvation and harshness, quicklydegenerate. So, too, stock that has been bred on poor pasturage willreadily improve if transplanted to richer pastures and milder climate. 

Therefore he who would prove himself an artist in moulding his herd atwill, must not only bring together into his herd many choice linesof goodness, but must ever seek, by kind treatment and good care, to change their qualities for the better, and by right selection andcareful breeding so impress these changes for the better as to makethem hereditary. If this course is persistently adhered to, the stockwill gradually improve, retaining the good qualities of the ancestry, and developing new ones, generation by generation, under the hand ofthe artist breeder. 

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THE BABYLONIAN PALACE. 

In a recent lecture on "Babylonian and Assyrian Antiquities, " atthe British Museum by Mr. W. St. Chad Boscawen, the architecture andornaments of a typical palace were described. The palace, next to thelocal temple, was, the lecturer said, the most important edifice inthe ancient city, and the explorations conducted by Sir Henry Layard, Mr. Rassam, M. Botta, and others, had resulted in the discovery of theruins of many of the most famous of royal residences in Nineveh andBabylon. The palace was called in the inscriptions the "great house, "as the temple was "God's house, " though in later times it was alsonamed "the abode of royalty, " "the dwelling-place of kings, " whilethe great palace of Nebuchadnezzar at Babylon, the ruins of which aremarked by the Kasr mound, was called "the wonder of the earth. " Thearrangement of the palace was one which varied but little in ancientand modern times, the same grouping of quadrangles, with intermuralgardens, being alike common to the Assyrian palace and the Turkishserai. 

The earliest of the Assyrian palaces were those built in Assur, whichdated probably from the nineteenth century before the Christian era;but the seat of royalty was at an early period transferred from Assurto Calah, the site of which is marked by the great mounds of Nimroudat the junction of the greater Lab and the Tigris. Here large palaceswere erected by the kings of the Middle Assyrian Empire, the mostlavish of royal builders being Assur-nazir-pal and Shalmanisar; whilea third palace was built by Tiglath Pileser II. (B. C. 742). Mr. Boscawen described the explorations carried out by Sir Henry Layard onthis site. 

The most important chamber in the building was the long gallery orsaloon, which had been called the "Hall of Assembly. " The variousparts of this palace included the royal apartments, the harem, andthe temple, with its great seven-stage tower or observatory. Thevery extensive and systematic explorations carried out by theFrench explorer M. Botta had restored the remains of one of the mostbeautiful of the Assyrian palaces. The usurpation of the Assyrianthrone by Sargon the Tartar in B. C. 721 placed in power a newdynasty, who were lavish patrons of the arts and who made Nineveh acity of palaces. Probably on account of his violent seizure of thethrone, Sargon was afraid to reside in any of the existing places atNineveh--though he appears for a short time to have occupied theold palace; he built for himself Calah, at a short distance to thenortheast of Nineveh, the palace town of Dun Sargina, "the fort ofSargon, " one of the most luxurious palaces--the Versailles of Nineveh. The ruins of this palace were buried beneath the mound of Korsabad, and were explored by M. Botta on behalf of the French Government, and the sculptures and inscriptions are now deposited in the Louvre. Compared with all the Assyrian palaces, later or earlier, this royalabode of Sargon stands alone. The sculptures were more magnificent, while warmth and color were obtained by the extensive use of coloredbricks. Some of the cornices and friezes of painted bricks, of whichMr. Boscawen exhibited drawings, were most rich in ornament. The chiefcolors employed were blue and yellow, and sometimes red and green. Having described the general construction of this remarkable building, Mr. Boscawen proceeded to speak of the character of Assyrian artduring the golden age (B. C. 721-625), and he illustrated his remarksby the exhibition of several large drawings. One of the most elaborateof these was the embroidery on the royal robe. The pectoral wascovered with scenes taken from Babylonian myths. On the upper partwas Isdubar or Nimrod struggling with the lion; below this a splendidrepresentation of Merodach, as the warrior of the gods armed forcombat against the demon of evil, while the lower part was coveredwith representations of the worship of the sacred tree. The generalcharacter of Assyrian art, its attention to detail, and the wonderfulskill in representing animal life, as exhibited in the hunting scenes, was next spoken of, and Mr. Boscawen concluded by a brief descriptionof the royal library, a most important part of the great palace atNineveh. 

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