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fell from another. During the expe- for our knowledge of many organs riments which this enquiry led him and materials adapted to that purto make upon snails, he discovered pofe, of which we had no concep

a very singular insect which lives tion before. In the course of this : not only upon these animals, but enquiry, M. Reaumur discovered

burrows in their bodies, a situation a fith different from that which which he never leaves unless he is furnished the ancients with their forced out of it by the snail. This Tyrian dye, but which has the

enquiry also gave occasion to M. fame property in a yet greater de: Reaumur to account for the pro- gree; upon the sides of this filh

gresive motion of teftaceous ani. there are small grains, like those mals of different kinds, and to de- of a hard roe, which being broken, scribe and explain an almost endless yield firft a fine full yellow colour, variety of organs which the author that upon being exposed for a few ofnature has adapted to that purpose, minutes to the air becomes a beauti,

He produced also the same year ful purple. the natural history of cob-webs. About the same time M. ReauM. Bon, the first president of the mur made a great variety of expechamber of accounts at Monpellier, riments, to discover whether the had shewn that the webs made by Itrength of a cord was greater or {piders to deposit their eggs in less than the sum of the strength of might be spun into a kind of filk, the threads of which it confifts. applicable to useful purpofes, but it was generally believed that the it was still necessary to deter- ftrength of the cord was greater, mine whether spiders could be bred bnt M. Reaụmur's experiments in fufficient numbers, without an proved it to be less, whence it neexpence too great for the under- cessarily follows, that the lefs a taking to bear, and M. Reaumur cord differs from an assemblage of foon found that M. Bon's discovery parallel threads, i. e. the less it is was a mere matter of curiosity, twisted, the stronger it is *. and that the commercial world It had been long asserted by those could derive no advantage from who lived on the sea coast, or the

banks of great rivers, that when It has been long known, that craw-fish, crabs, and lobsters, many marine animals adhere to fo- happen to lose a claw, nature prolid bodies of various kinds, either duces another in its stead. This, by an attachment which continues however, was disbelieved by ali during their existence, or which but the vulgar, till M. Reaumur they can determine at pleasure; put the matter out of dispute, and but how this attachment was form- traced the re-production through ed, remained a secret, till it was all its circumstances, which are discovered by M. Reaumur, to even more singular than the thing whose enquiries we are indebted itself.

these webs.

That mode of uniting various thưeads into a cord, is undoubtedly the best, which causes the tensions of the threaels to be equal in whatever dire&tion the cord is Strained; and this consideration is fufficient to render the common method of combining threads into cords by twifting; preferable to all others.

M.

of erecting a monument

, but the REne-Anthony Ferchault, lord

with a plain ftone ; cardinal Cyn- ance. His writings make it unthio, whom he made his heir, al- . necessary to mention the natural enways professing an intention of dowments of his mind, but it is erecting a monument to his me faid of him, that there never was mory, but though he survived a scholar more humble, a wit more many years, yet he died without devout, or a man more amiable. putting it into execution. Manso, to whom he left pothing but his picture, when he came, ten years Some account of the life of the celeafter his death, and found not so brated French academift Monfieur much as his name inscribed upon DE REAUMUR. the fone that lay over him, would have taken upon himself the care

he of Reaumur, was born at Rowas not permitted; however, he chelle in the year 1683: he learnprocured the words, Hic jacet Ter- ed grammar at the place of his quatus Tassus to be engraven on the birth, and studied philosophy at ftone that covered his

grave. A the Jesuits college at Poitieres : in ftately monument was at last erect. 1699 he went from thence to Boured to his memory in the church ges, at the invitation of an uncle, where he was buried, by cardinal where he studied the civil law : in Bonifacio Bevilacqua, of an illu- 1703 he went to Paris, and applied Itrious family of Ferrara.

himself wholly to the mathematics He was tall and well shaped, his and natural philofophy; and in 1 708, complexion fair but pale; the hair being then only four-and-twenty of his head was of a chesnut co

years old, he was chosen a member lour, that of his beard fomewhat of the royal academy of sciences lighter, thick, and busy; his of that city, and during that and forehead was square and high, his the following year, he described a head large, and the fore-part of it general method of finding and in the latter part of his life, bald; ascertaining all curves described by his eye-brows were dark, his eyes the extremity of a right line, the full, piercing, and of a clear blue; other end of which is moved round his nose large, his lips thin, his a given curve, and by lines which teeth well set and white, his neck fall upon a given curve under a well proportioned, his breast full, certain angle greater or less than a his shoulders broad, and all his right angle. limbs were more finewy than fleshy. These are the only geometrical His voice was strong, clear, and performances that he produced ; in folemn; he spoke witii deliberation, the year 1710, he read his obserand generally reiterated his lait vations upon the formation of thells, words: he seldom laughed, and in which he proved that they grow never to excess; he was very ex not like the other parts of the anipert in the exercises of the body. mal body by expansion, but by In his oratory he used little action, the external addition of new parts ? and pleased rather by the beauty He also asigned the cause of the va, and force of his language, than riety, in point of colour, figure, and by the graces of gesture and utter- magnitude which diftinguishes one

fhell

hellfrom another. During the expe- for our knowledge of many organs riments which this enquiry led him and materials adapted to that purto make upon snails, he discovered pofe, of which we had no concepa very singular insect which lives tion before. In the course of this pot only upon these animals, but enquiry, M, Reaumur discovered burrows in their bodies, a situation a filh different from that which which he never leaves unless he is furnished the ancients with their forced out of it by the snail. This Tyrian dye, but which has the enquiry also gave occasion to M. fame property in a yet greater deReaumur to account for the pro gree; upon the sides of this filh greffive motion of teftaceous ani. there are small grains, like those mals of different kinds, and to de- of a hard roe, which being broken, fcribe and explain an almost endless yield first a fine full yellow colour, variety of organs which the author that upon being exposed for a few ofnaturehas adapted to that purpose, minutes to the air becomes a beauti,

He produced also the same year ful purple. the natural history of cob-webs. About the same time M. ReauM. Bon, the first president of the mur made a great variety of expechamber of accounts at Monpellier, riments, to discover whether the had shewn that the webs made by itrength of a cord was greater or {piders to deposit their eggs in less than the sum of the strength of might be spun into a kind of filk, the threads of which it confifts. applicable to useful purposes, but It was generally believed that the it was still necessary to deter- ftrength of the cord was greater, mine whether spiders could be bred bnt M. Reaumur's experiments in sufficient numbers, without an proved it to be less, whence it neexpence too great for the under- cessarily follows, that the less a taking to bear, and M. Reaumur cord differs from an assemblage of foon found that M. Bon’s discovery parallel threads, i. e. the less it is was a mere matter of curiofity, twisted, the stronger

it is and that the commercial world It had been long asserted by those could derive no advantage from who lived on the sea coast, or the

banks of great rivers, that when It has been long known, that craw-fish, crabs, and lobsters, many marine animals adhere to fo- happen to lose a claw, nature prolid bodies of various kinds, either duces another in its stead. This,

an attachment which continues however, was disbelieved by all during their existence, or which but the vulgar, till M. Reaumur they can determine at pleasure; put the matter out of dispute, and but how this attachment was form- traced the re-production through ed, remained a secret, till it was all its circumstances, which are discovered by M. Reaumur, to even more fingular than the thing whose enquiries we are indebted itself.

these webs.

by

That mode of uniting various threads into a cord, is undoubtedly the best, which causes the tensions of the threads to be equal in whatever direction the cord is ftrained; and this consideration is fufficient to render the common method of combining threads into cords by twifting; preferable to all others.

M.

M. Reaumur, after many expe- ing the vast bank of foslil shells, riments made with the torpedo, or which, in Touraine, is dug for numb-fish, discovered that its ef- manure, called falun : 2d. Upon fect was not produced by an emif- Aints, proving that they are oniy fion of torporific particles, as more penetrated by a stony juice, fome have fupposed, but by the or, if the expression may be allowgreat quickness of a stroke given ed, more ftonified than other stones, by this fish to the limb that teuches though lefs than rock crystal : 3d, it, by muscles of a most admirable Upon the notoch, a singular plant, structure, which are adapted to that which appears only after hard rains purpofe.

in the fummer, under a gelataneous These discoveries, however, are form, and soon after disappears : chiefly matters of curiosity, those 4th, Upon the light of dails, a which follow are of use.

kind of shell fith, which fhines in It had long been a received opi- the dark, but loses its luftre as it nion, that turquoise ftones were grows ftale : 5th, Upon the facifound only in Perfia; but M. de lity with which iron and steel beReaumur discovered mines of them become magnetic by percussion. in Languedoc; he ascertained the In 1722, he published a work degree of heat necessary to give under the title of The art of conthem their colour, and the proper verting iron into fteel, and of renderform and dimensions of the furnace; ing caft iron ductile. he proved also that the turquoise The use of iron is well known is no more than a fosil bone petri- under the three forms of cast iron fied, coloured by a metallic folu- forged or bar-iron, and steel: iron tion which fire causes to spread; in the first state is susceptible of and that the turquoises of France fufion, but it is brittle and hard, are at leait equal in beauty and and can neither be forged by the {ze to those of the east.

hammer, nor cut by the chiffel: M. de Reaumur also discovered in the second state it is malleable, the secret of making artificial pearls, and may be both filed and cut, but and the substance neceffary to it is no longer fusible without the give them their colour, which is addition of a foreign substance: in Caken from a little fish called able, the third it acquires a very singular or ablette. He drew up, at the property of becoming hard and fame time, a differtation upon the brittle, 'if after it has been made

arl, which he supposed to red hot it is dipped into cold water: be a morbid concretion in the the extreme brittleness of cast iron body of the animal.

makes it un fit for the construction M. de Reaumnur soon after pub- of any thing that is required to be Tished the history of the auriferous supple, and kill more for any thing rivers of France, in which he has upon which it will be necessary to giren a very particular account of employ a tool of any kind after it the manner of separating the grains conies out of the font, for no tool of gold from the fand with which can touch it. On the other hand, it is mixed.

the manner of converting forged Among other memoirs lie drew or bar-iron into steel, was then up the following: ift, Concern- who'ly unknown in France.

But

true

Bat M. Reaumur having, in the He invented the art of making course of other enquiries, found porcelain. A few simple observashat steel differed from iron only tions upon fragments of glass, in having more sulphur and more porcelain, and pottery, convinced falt in its composition, undertook him that china was nothing more to discover the method of giving than a demi-vitrification ; now a to iron what was wanting to make demi-vitrification may be obtained. it steel, and at length perfectly either by exposing a vitrifiable succeeded, so as to make steel of matter to the action of fire, and what quality he pleased.

withdrawing it before it is perfect: The fame experiınents, which fy vitrified, or by making a pate convinced M. de Reaumur that of two substances, one of which fteel differed from iron only in is vitrifiable, and the other not: having more fulphur and salt, con

it
was
therefore

very easy to difvinced him also that cast iron dif- cover by which of these methods fered from forged iron, only by the porcelain of China was made ; having still more fulphur and falt nothing more was necessary than to than steel ; it was steel with an urge it with a strong fire; if it conexcess of its specific difference fifted wholly of a vitrifiable matter from forged iron : he therefore set half vitrified, it would be converthimself about taking away this ex- ed into glass; if of two substances, cess, and he succeeded so well, as to one of which was not vitrifiable, produce a great variety of utensils it would come out of the furnace in cast iron, which were as easily the same as it went in : this expewrought as forged iron, and did riment being made, the China not coft half the money. However, porcelain suffered no alteration, but a manufactory set on foot in France all the European porcelain was for rendering cast iron sufficiently changed into glass. ductile to be forged and wrought, But when the China porcelain was, after some time, disconti was thus discovered to confift of nued, and has never been revived two diftinct substances, it was farfince, though for what reason does ther necessary to discover what they not appear:

were, and whether France proFor discovering the secret of duced them. M. Reaumur acconverting iron into steel, the duke complished these defiderata, and of Orleans being then regent, fct- had the satisfaction to find that the tled a pension upon M. de Reau- materials for making China porcemar of 12,000 livres a year, and, lain were to be had in France in at his request, it was settled upon the fame abundance, and in greater the academy after his death, to be perfection than in India. M.' applied for defraying the expences Reaumur also contrived a new speof future attempts to improve the cies of porcelain, consisting only

of glass, annealed a second time, M. de Reaumur also discovered with certain eafy . precautions, the secret of making tin, as it was which, though less beautiful than practised in Germany; and his other porcelain, is yet a useful dis. countrymen, instructed in that uie- covery, considering the great faciful manufacture, no longer im- lity and cheapness witli which is ported tin from abroad.

is inade.

M.

arts,

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