Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/559

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prsecordia, or between the duplicatures of the mediaftinum, with many bad fymptoms of the like nature. The fignS of a fra£turcd fternum will therefore be very evident by thefe, and by its being moveable to the touch, especially when one part of it grates againft another, and when there is a cavity and inequality very remarkably viable there. In order to reduce a fracture of this bone, the patient mufl be laid on his back on a bed, or hard even place, as a table, putting a hard pillow, a large parcel of cloth rolled up, or fome other fuch body, under his back, and prefling down his fhoulders, by which means the fractured fternum will he elevated and extended ; and to facilitate the reduction, the furgeon mufl: prefs the bones of the fternum together, and ihakethem very ftrongly. But when this method is imprac- ticable, or not proper, the flcin mufl: be divided, and the deprefled part of the fternum lifted up into its place, by means of an elevator, or elfe of a fcrew gently wormed into the part, and afterwards pulled upwards ; and when it has re- gained its natural fituation, it mufl: be kept in it by the pro- per bandages. If after the reduction violent pains continue under the fternum, and if blood mould gather, and fuppu- rate internally, between the duplicature of the mediaftinum, the' lower- part of the fternum ought to be trepanned, as the cranium on the like occafions ; and when the putrid -matter is difcharged, and the wound cieanfed, it mufl: be healed with vulnerary balfams; and if any blood fhould be found dif- charged into the cavity of the thorax, the cure mufl: entirely depend on the evacuating that by the paracentefis, in the manner of wounds of the thorax. Heifer, p, 122.

STHENIA, E0m«, in antiquity, a feftival of Argos, fuppofed to be kept in honour of Minerva, furnamed X&tvtxf from dW, ftrength. Potter, Archseol. Grsec. Tom. I. p. 430.

STIiE, a word ufed by fome of the old authors for pebbles found on the fea-fhore.

STIBIALIA, a term ufed by fome to exprefs the antimonial medicines.

STIBADIUM, among the Romans, a low kind of table- couch, or bed of a circular form, which fucceeded to the triclinia, and was of different fizes, according to the num- ber of guefts they were defigned for. They were called hexadina, oSladina, or enneaclina, according as they held fix, eight, or nine guefts, and fo of any other number.

STIBINUS color, a term ufed by St. Jerom, and others, to exprefs the falfe black colour which the antient Jews, and other Eaftcrn people, gave to their eye-brows with ftibium, or antimony.

STIBIUM, antimonium, antimony. See Antimony, Cycl This is a mineral never found native in its perfect ftate, but always intimately mixed with, and penetrated by ful- phur, and other extraneous matter, and by it reduced to the ftate of an ore. In this condition it is ever found in the earth, and according to the different proportions of ful- phur, or other matter, it contains, it affumes very different appearances.

It is moft commonly found in form of a very hard and heavy lead-coloured fubftance, compofed of a number of extremely fmall granules, all very bright and fparkling, and giving it the appearance of a lump of the pureft fteel when frefh broken. This is what is commonly underftood by the name antimony ore, and is what is fold under that title in the Ger- man fhops.

Not unfrequently, however, it appears of a fomewhat more lax texture, lefs heavy, but much more bright, and com- pofed of fmall, but vifibly broad and flat particles, of a very pale whitifh lead colour, and glittering appearance, like that of many of the lead ores. This is called broad-grained an- timony ore.

Sometimes alfo, but lefs frequently, antimony appears in form of bright manes, made up of multitudes of parallel flender filaments, of a bright fteel colour, and more glittering hue than in either of the former Hates : thefe filaments are of different breadths and thicknefl.es in the feveral manes. Thefe are generally known by the name of ftriated, or plumofe antimony ore.

Thefe are the moft natural and fimple appearances of this foflil, but befide thefe it is liable to a multitude of other very different ones, as it fometimes contains iron mixed among its own matter, and very frequently filver ; thefe may natu^ rally be fuppofed to give it fome differences in its appear- ance : but befide thefe it is fubject to much greater, from its admixtures with the common marcafites and pyrits ; thefe often tinge the whole body of the ore to a filvery white, or to a golden yellow.

Antimony ores are found in fiflures and veins at different depths, and often very near the furfacc, and is varioufly ac- companied with fpars, cryftals, fulphurs^ and other fub- ftances. Sometimes the veins of it are every way furrounded by a tolerably pure yellow native fulphur j fometimes with a more debafed matter, made of a mixture of fulphurs, earth and fpar, differing according to the different difpofition and admixture of thefe bodies.

Antimony is found in great abundance in England and Ger- many ; we have feveral mines of it in Cornwall ; and Ger- Suppl. Vol. II,

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many, Hungary, and many other parts of the world, afford it in very great abundance.

To reduce it to a ftate fit for ufe, it is to be feparated from its ore by the force of fire, and by the afliftance of fuch ingre- dients as break the mutual connection between the fulphure- ous and the reguline part, which mutually diflblving each other, keep the concrete in the ftate of ore. The addition of iron is able to do this ; and that of filver, copper, and other metals, has alfo the fame effect.

There have not been wanting perfons, who have pretended to extract a mere running mercury from antimony, and Mr. Boyle believed it might be done : but this is one of the many great things pretended to by chemiftry, of which we have yet no fufficient proof.

Antimony, when feparated from its ore, is very eafily fufi- ble, and runs the thinneft of all the bodies of this kind. It greatly promotes the fufion of other feffils, but it makes every thing brittle that it is mixed with. It is of great ufe in medicine, chemiftry, and mechanics, and in its feveral preparations is diaphoretic, cathartic, and emetic. The cne- mifts ufe it greatly in their operations on other metals, and it is an ingredient in pewter, bell-metal, and the mixt me- tal, of which types are made for printing. HUH Hift. of Foil. p. 623.

Mr. Geoflroy has been the inventor of a new method of treating this mineral, by which it yields much more regulu3 than according to thofe prefcribed by Kunkel and Stahl, and is purified without the addition of falts, and with very little lofs.

It is generally fuppofed, that the vapours of antimony are poifonous when raifed by fire, but it appears otherwife from the operations this gentleman made on it ; the fame opera- tor having once gone through fixty calcinations of twelve ounces of antimoyiy, without receiving any harm from it J whence it is very evident, that the common opinion of the fumes of antimony containing an arfenical fulphur is an er- roneous one ; and it may be added, that one great mark of antimony's being good, is, that it lofes a great deal of its weight in calcination. It has more fulphur in this cafe, which the fire raifes in a vapour, and lefs of the terreftrial matter or fpar, which are ufually very abundant in it. It has been proved by experiment, that the fulphur of antimony is a neceflary and eflential part of its conftruction, fince without this it is no longer emetic; but this fulphur is only neceflary in a certain proportion ; for it is found, that when it is more abundant in the antimony, the whole lofes in pro- portion of its emetic quality ; and Mr. Geoffroy has found by repeated experiment, that to give this virtue in its greateft: degree, the antimony is firft to be divefted of its native ful- phur, much of which is of no ufe as to this intention, and is then to be melted with a gentle fire in a crucible with a quantity of foap, made from a ftrong lixivium of pot-afhes, quick-lime, and oil, united by boiling into a folid mafs. The antimony melted with this, after a fufficient previous cal- cination, affords a fort of glaffy cruft: of fcoria?, which covers a quantity of compact regulus lying at the bottom of the crucible. Thefe fcorias are a fort of blackifh glafs, which melts in the flame of a candle, but does not run on being expofed to the air. This is plainly compofed of the burnt oil of the foap, united with the acid of fulphur of antimony, and a vitrification made with fome earthy particles, and the falts of the foap ; this vitrification is what preferves the fatty matter from being liquified by the air. When thefe fcorias are feparated from the reguline matter, if that be again melted, with an addition of an alkali fait and of the powder of white cryfta! glafs, there is produced a purer regulus than can be obtained by any other known method, and in a larger quantity, by two ounces from the pound, than ever Stahl, or Kunkel, were able to procure. Mr. Geoffroy, by thefe nice obfervations and experiments, difcovered that an- timony contained much lefs common fulphur than had been generally fuppofed, fince it can be made to lofd, at the ut- moft, only three ounces and five drachms in the pound in calcination. The emetic quality of the regulus proves, however, that it yet contains a very large fhare of fulphur, though of another kind : this Mr. Geoffroy diitinguimes from the common fulphur, by the name of the metallic ful- phur. Mem. Acad. Scienc. Par. 1736. Acid of Antimony. Mr. Charras was the firft author who gave the world a fuccinct method of drawing an acid liquor from antimony. He did it thus : he mixed crude antimony ore in powder with three times its weight of {and, this he diftilled in a large retort into a capacious receiver, filled half full of river water, and on rectifying this, the acid liquor was to be produced. Himfelf acknowledges, however, that this, though a fuccinct, is not always a certain method, for that fometimes the acid liquor was produced, and fometimes not: this, however, he attributes wholly to the manage- ment of the fire, which he fays will always afford the acid, if conducted regularly through its feveral degrees. But Mr. Homberg trying tins experiment feveral times, and finding it fometimes fucceed, and at other times not, though the fame cautions were ufed, difcovered at length that this va- 3 I i i riation 3