Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/238

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all her pores and abforbent veflcls with a gr^at quantity of cam* phor. The woman at Ipfwich had drank plenty of gin ; which circumftances muft greatly promote the kindling the pbofpbo- real fire in them: and as this pabulum was conveyed into the rrioft minute capillary veflels, it might produce an almoft in- stantaneous deflagration and diffolution of all the folid con- taining parts. Phil. Tranf N°. 476, p. 447. feq. Ammoniacal Phosphorus, inchemiftry, the name of a pbefpbo- rus, compofed of fal ammoniac and lime, which Mr. Hom- berg firft difcovered.

The method of preparing it is this : take one part of fal am- moniac in powder, and two parts of lime extingmfhed by ly- ing in the air : mix them exactly together, and fill a crucible with the mixture; fet it in a fmall melting heat. As foon as the crucible grows red hot, the matter in it will melt, and it muft be ftirred with an iron rod, left it fwell o^'er the edges of the crucible: as foon as the whole is melted, pour it into a copper bafon ; it will appear of a greyifh colour and vitrified, and if it be ftruck upon with any hard body, there will be feen a fire all over the place where the blow was given, As this matter is brittle, however, and the fame mafs will not ferve often for the experiment, the beft method is to dip iron rods in it ■while melting, and thefe will be covere I with the matter, and will anfwer the purpofe cafdy and often. Mem. Acad. Par- 1693. jf?iti?/w?iiat Phosphorus-, in chemiftry, the name of a fubftance having the qualities of the pbofpbirus difcovered by Mr. Geoffroy in his experiments on antimony. This gentleman had pre- pared a foap from pot-afhes, quick-lime, and oil, with which he made feveral experiments on antimony; among others he was defirous, by means of this, to reduce fome diaphoretic antimony, which he had before made from two parts of the regulus of antimony, and three parts of nitre; but inftead of the reduction which he was labouring after, bis operation af- forded him a much more lingular phenomenon : the refult of them being a phofphorui, which he had never thought of; a matter, which after having remained perfectly quiet while clofe flopped down, took fire as foon as ever it was expofed to the air j and that with a violent detonation, and darting every way a fhower of fire.

It is ealy to fee, that there are in the preparation all the re- quifites for fuch an effect; nitre, charcoal furnifhed by the burnt foap, and fulphur both from the foap and from the regu- lus of antimony ; and to all thefe, a fort of calx, either from the foap, or from fome earthy parts of the antimony. It is eafy to conceive, that all thefe fubftances coming to a mix- ture together, fhould be ready to catch fire and blaze upon a proper application ; but it is not lefs difficult to account for this effect's being produced merely by the air, after the whole had been for a long time in a ftate of reft. The method of preparing this new fpecies of pbofpborus is this : Mr. Geoffroy mixed two ounces of his foap with one ounce of this diaphoretic antimony ; this mixture being put by little and little into a red hot crucible, took fire, and fwelled very much. After it had done flaming, the mafs fubfided, and became a red or fire-coloured fubftance, of an even fur- face, but ftill throwing up a vaft quantity of bluifh-green lu- minous vapours : and all this regularly happened on every frefh throwing in of the matter, without the leaft variety. When the whole quantity was thrown in, and had ceafed to give any flame or luminous vapour, it remained in the cru- cible in the form of an inverted mufhroom, being hollow, very porous, and of a black colour. When the crucible was taken out of the fire, the edges of this fubftance were beaten down into the middle, and the whole covered with an ounce of frefh foap. When this laft foap was burnt, and a fmall blue- ifh flame appeared upon the furface of the mafs, the crucible was covered with a lid, and a large quantity of charcoal laid upon it, and the fire blowed up very brifkly, by an hundred blafts of the bellows, or thereabouts ; but notwithftandig the fiercenefs of the fire, there was no fluid fcorise formed, but the whole mafs remained fpungy and porous. The fire was then fuffered to go out, and the crucible placed in a corner of the elaboratory at reft for five hours. In the evening, when the crucible was perfectly cold, Mr. Geoffroy went to exa- mine the matter, and a fervant went to uncover the mafs, by removing its furface with an iron inftrument ; but the mo- ment the air was admitted, the whole mafs took fire, burning with a very confiderable noife, and darting its flames every way to a great diftance.

Mr. Geoffroy repeated the procefs feveral times, and always with the fame fuccefs, whether he ufed his own diaphoretic antimony, or that made in the common manner. The great caution to infure the fuccefs, feems to be the taking care of not carrying the fire too far before the addition of the laft quantity of foap. Mem. Acad. Scien. Par. 1736. Jquntic Phosphorus, a name given by Dr Leigh, in his hifto- ry of Lancashire, to a water found near Wigan in that county, which takes fire on holding a lighted candle to it. It is not properly the water, however, that takes fire in this cafe, but a fteam which burfts out of the ground with it. The author alfo calls it a fulpburatcd water ; but that very improperly, for it contains no fulphur, but only iffues out in company with this bituminous vapour. Ph&SPHORV'S of the bearnc-Jio'.ic, in natural hiftory, is a name gi-

PHO

Ven to a ftone, (which, when heated, becomes a fort of pirfpborus) from the place where it is found ; as the famous one of Bologna is called alfo from its native region. The beame-Jione is of a moderate hardnefs, confiderably pel- lucid, and ufuaily colourlefs, or whitifh, tho' fometimes widi a tinge of green, yellow, or fome other colours : it is com- pofed of numbers of plates, or flakes, laid one over another) in the manner of the ifiand cryftal ; and therefore, like that body, is plainly a fpar. It breaks into feveral faces, and has different angles ; but of a fomewhat determinate meafure, the acute ones being of fixty degrees, and the obtufe ones of 120. Mem. Acad. Par. 1724.

This ftone, when heated at one of its angles with the flame of a lamp or candle, fphts by means of the flame's infinuating itfelf into the interftices of the plates that are lefs firmly united ; and thefe feparate, and fome fragments ufuaily fly off with confiderable violence. One of thefe pieces carried into an ob- fcure place, appears furrounded with a blue flame, which lafts about a minute. And it is to be obferved, that thefe pieces which fly off, have all the fliape of an irregular pyramid, wiih an uneven bafe. If this ftone be put into a crucible, and fur- rounded with coals, it becomes a very beautiful jhofpborm. The whole bottom of the crucible is feen, even tho' it be in broad day light, mining with a bright and beautiful blueifh white ; and if it be carried into a dark place, the light is feen much more beautifully. If, after it is cold, it be a«;ain heat- ed in a crucible, in the fame manner it fhews the lame bright appearance. After this, if it be tried a third time, h does not ihine at all. According to all thefe phenomena, the effects of fire upon this ftone feem to depend on a fulphur contained in it, probably of the fame nature with that which enters the compofition of the metals. This may, by means of a heat, fuch as that given by the candle or in the crucible, difengage itfelf fo far from the body of the ftone as to take fire ; and when it has burnt fo long as to confume itfelf, the luminous property of the ftone feems to ceafe.

The coloured gems are cryftals of a peculiar kind, tinged with the fulphurs of metals: this fulphur gives them their colour, and confequently it ought to give them the properties of the bearne -Jlone, if it were not too fixed to be diffipated in the fame eafy manner, and to take fire in the diflipation. And it appears on trial, that the baftard emeralds of Auvergne and other places, the matrix of the amethyft, the fragments of fome of the accidental jafpers, thejacynths, and fome fort of rubies, are all phofpborufes of the nature of the beanie- ft 'one, but with different degrees of brightnefs. The mother of the emerald, the yellow jafper, the water fapphire, the malachite, the opal, and the garnet, have none of them any of this property. Mem. Acad. Par. 1724.

Since the fame fulphurs which take fire in the beame-Jione^ are what give colour to thefe other ftones, it ftiould feem, that thofe which are not of this phofphorui kind, nor give alight after being heated, fhould not lofe their colours in the fire ; and this is found to be true in the garnet, which does not lofe any part of its colour, nor is it at all luminous ; whereas the hyacinth, and fome of the jafpers and other ftones, which lofe a part of the colour, not the whole, in the fire, become alfo in part luminous, or more fo, in degree, according to the quantity of colour which tbey lofe. This, however, is no cer- tain rule, fince the mother of the emerald, the topaz, and fome other ftones, lofe all their colour, and yet are not at all luminous. The reafon of this feems to be, that the fulphurs are driven out of thefe ftones fo flowly, and in fuch minute quantities, that they are not at any time collected into body enough to be capable of flame. 'I here is nothing to be ob- jected as to the beame-Jicnesfhimng ; tho' they are ufuaily white, they may poffefs no fmaller portion of fulphurs than the coloured ftones ; only in thofe the fulphurs may be colourlefs, or white in themfelves.

It may be poffible alfo, that the fulphurs, in a ftone of this kind, may be difperfed in fuch fmall molecules, as not to form a body fufficient to give any colour ; but when collected, in order to be driven off in the fire, they may then be fufficient in quantity to give a blue tinge to the flame. The ifiand cryftal, which is alfo a fpecies of fpar, and which greatly refembles this bearne-Jlone in many particulars, flies to pieces alfo in the fame manner, on being heated ; and when carried into the dark, this alfo gives fome fparks of light, but they are few in number, and loufely fcattered over the furface : when this ftone is burnt a little in a crucible, there is fome fmall appearance of flame, with a fmell of fulphur, and the matter in the bottom of the crucible is found {battered to pieces ; but all the pieces are regular parallelopipcds, as was the original mafs. Mem. Acad. Par. 1724. It is to be obferved, that thebearne < jhne, and others of tl.e fame kind, which only fhine in the dark, and that only for a few minutes, when firfc taken out of the fire, are, properly fpeak- ing, endued with no other luminous quality, than that of a burning coal ; but their light having been generally unobferved, and requiring darknefs to fhew it, has obtained them the ipe- cious title of pbofbcrl. Phosphorus fetalis, a very fine kind of phofphorui r, exhibiting many wonderful phenomena, and prepared from human dung mixed with alum.

Mr.