Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/397

 SAL

SAL

regard, which is, that the mixtures fometimes afford more volatile alkali than the weight of the whole quantity of fal ammoniac from which this volatile alkali is drawn ; befide that, there muft be fuppofed to remain all the acid matter at the bottom of the veffel ; but the whole account of this muft be, that this volatile urinous fait is fo extremely power- ful, that it raifes and carries up with it a part of its other matter.

It remains, however, yet to enquire why lime alone being joined with fal ammoniac in diftillation, yields this volatile al- kali in a liquid form, or in theftateof fpiiitof fal ammoniac. There feldom rifes any thing in a dry form in this procefs ; when there does it is but very little ; and when there arifes no liquid, as is fometimes the cafe, there arifes often no- thing; at all; whereas, with the other alkalies, there arifes, as has been feen, more than the weight of the whole quan- tity of fal ammoniac. We very well know that this liquid fubftance, which we call fpirit, is no other than the fame volatile fait diffolved in water, or in fome other humidity, furnimed by the matter, added to the fait in the diftillation, and that this fait in rifing has brought up its dlffolvent with it. The lime, though deprived in a great degree of its hu- midity, by the operation which made it lime, yet retains enough for the purpofe of melting the fait into what we call this fpirit ; and when the operation with time does not fuccced it \i owing to this, that the calcination of the lime has been fo per- fect, as to deprive it of all its humidity ; and the truth of this is evident, fince the adding a little water will always enfure the rifing of a fufficient quantity of fpirit, and that with lefs fire than it can be obtained with when no water is added. We are yet at a lofs, however, to account for lime's acting differently from all the other additions to this fait, and making nothing arife in a dry form. Mr. du Hamel obferves, that by its formation, lime is di- verted of all acids, and of all humidity ; but that by means of its fatty particles, whether they are from fhells em- bodied in the ftones from which it was made, or from the natural' bitumen of {tones, it is always endeavouring to re- cover what it has been diverted of by fire ; that it abounds with a vaft number of fiery particles ; and that by means of thefe, it is enabled to aft upon the urinous, and therefore fatty matter of the fal ammoniac ; whether it be, that it unites itfclf intimately with it, fo as never to be feparated from it, or whether it decompounds, and as it were burns it. And what confirms this conjecture, is, that Mr. du Hamel having diftilled four drachms of fpirit of fal ammoniac with one drachm of frefh lime, he obtained a fmal! quantity of volatile fait in a dry form ; the lime in fo fmall a propor- tion not being able to prevent the fait from this fpirit from appearing in a dry form. And it is eafy to conclude hence, that a volatile fait might be obtained from fal ammo- mac with lime, in a dry form, provided that the fal ammo- niacbe mixed in an over proportion up to a certain quantity. Mem. Acad. Scien. Par. 1735.

The fpirit and fait of fal ammoniac being the fame matter in a dry and a liquid form ; it is evident, that the liquid muft of the two be moft ftriking to the nofe, becaufe the parti- cles of the fait arc more eaiily difunited from this latter union : and the fait, in a dry form, is fo very volatile, that it entirely evaporates when laid on a hot iron, however fixed the matter may have been, which it originally carried up with it. It appears very plain from this, that the union be- tween this volatile body and the particles of more fixed ones, which it carries up with it in fublimation, and which are proper to give it the form of a dry concrete, is fo intimate, that it will bear very feverc trials and remain unaltered, and indeed, that it is fcarce poflible at all to decompofe it. It is no indifferent matter what the additions are with which fal ammoniac is diftilled ; they muft, by no means, be either iiich as contain a nitrous, or a vitriolic acid ; the former of thefe meeting with the fatty and fulphurous part of the fal ammoniac, may caufe a detonation and burft the veiTels ; and the other,which is yet much more dangerous, might difengage a portion of the fea fait, which would again mix with the vo- latile part with which it has now no bufinefs to be allied, and with the fatty matter it might form a very difagreeably fcented fulphur. Bole contains a vitriolic acid, and is there- fore to be rejected. Gypfum mixed with it gives a fmoak- ing liquor, whofe odour is infupportable, and chalk and common pot-afhes are the beft of all additions. Thefirft ■wiho gave fal ammoniac internally was Platerus; but its ufc in fevers was not then known ; he only ufmg it in afth- mas. Infucceeding times it became known as a febrifuge. It is frequently ufed in this intention, in Germany and Holland, and with great fuccefs. The common dofe to a grown perfon is one drachm. The largeft dofe, in cafes of the moft robuft con- stitutions, is two drachms. A perfon of eleven or twelve years old may take two fcruples, and an infant of a year old may take fourteen grains. Its chief virtue is in intermit- tent fevers, in which it may be thus given. Let the dofe of fal ammoniac, proportioned to the age and ftrength of the pa- tient, be diftblved in an ounce of common water, or of any diftilled water ; and let the patient take it half an hour be- fore the time that the fit is to come on. This is to be re-

peated in the fame manner, before every fit, till the difterr- per is removed.

Though the great ufe of this medicine be in intermitting fe- vers j it is not, however, adapted only to thofe, but may be of ufe in fevers of other kinds. The fame dofe may be taken every five or fix hours, drinking a bafon of fage tea after it. It very frequently fucceeds fo well, that one dofe of it carries off the difeafe, fo that it never returns again ; but if the firft dofe does not fucceed in this manner a few others will. Two, three, or four dofes almoft always prove fuf- ficient. This medicine has no vifible effect upon the body* more than the fudden removal of the ficknefs ; for it neither operates by vomit, nor by ftool, nor 'by fweat : its effect feems to be owing to the correcting and altering of the mat- ter of the difeafe, not the evacuating it out of the body. The bark is fuperior to this fait in the cures of quartan agues, and indeed in other cafes it is more certain in the {topping a fecond fit; but there is another advantage in this, which the bark greatly wants, this is the preventing re- Iapfes. Thefe are very frequent after cures in the common way, but are fcarce ever found to follow in cafes when this fait has been ufed.

Another advantage of this medicine is the fmall quantity of the dole, and the few dofes that are neceffary to be taken for a cure ; whereas every one knows how many laig,e dofes of the bark are neceffary, and that often at fuch fmall dis- tances of time, in cafes, that it is often difficult to perfuade the patient to be cured at the expence of fo naufeous a load of medicines. Act. Erudit. 17 17.

Sal aquarum, in natural hiftory, a name given by many of the antient writers to the nitre of the antients or natrum. They had this fait principally from ./Egypt, and called it in their works the produce of the evaporated waters of the Nile ; for this reafon Hippocrates fometimes calls it fal <£gypu t and fometimes fal inaquis enfeens, & fait growing in the waters.

Sal circulatum, in chemiftry, a term ufed by Paracelfius for a preparation of fea fait, of which he diftinguifhes two kinds, under the name of the circulatum minus and circulatum majfis* Thefe feem to have a great affinity with the famous alkaheft or univerfal folvent, fo much talked of in the works of this author, and his fuccefforVan Helmont.

The circulatum minus was a liquor procured by a tedious procefs from fea fait ; this fait, he fays, is that body in which nature has placed the greateit perfection ; and from this he, by incredible induftry, procured a liquor which he calls a perpetual oil, and to which he alfo gives the name of the ens primum of falts. He calls it the higheft and moft fuccefsful of all falts, and declares that all poifons are fubdued by It ; and that being brought to the utmoft degree of purity and fubtilty, it pervades all bodies, and readily diffolves them, itfelf remaining unaltered in the action. Thefe are all properties exprefsly attributed by Hel- mont to the famous alkaheft. See Alkahest. The circulatum majus, however, we are told, by the fame au- thor, was much more powerful and much more difficult to be obtained than the former. This he calls the matter of mer- curial fait, and the living fire: he acknowledges that the higheft fire and ccleftial "life lie hid in common mercury, and fays the quinteflence of mercury is celeftial fire : by this and a great many other enigmatic expreffions in 1 his writer, there is room to believe, that the alkaheft, delcribed by Helmont, is a preparation of mercury and fcafaits. Boerh. Chem. p. 573.

Sal diitreticus, a form of medicine, of the nature of the terra foliata tartari, introduced into practice by the late college difpenfatory. The method of preparing it is this : take of any alkaline fixed fait a pound, boil it in four or five pints of diftilled vinegar in a gentle heat. When the fermentation is over, pour on more diftilled vinegar ; and when the fer- mentation arifmg from this addition is over, pour on {till more, and proceed thus till the moifture being nearly al! evaporated, frefh vinegar being added will excite no more fermentation : this generally happens when about ten quarts have been ufed ; then evaporate to a drynefs ; the fait will be impure, and muft be melted for a fmall time, with a gentle beat, afterwards diffolved in water, and filtered ; if the melting has been rightly performed, the {trained liquor will be pellucid as water; then evaporate this in a gentle heat to a drynefs, and you will have a very white fait, fo- luble either in water or fpirit of wine. Pembertoris Lond. Difp. p. 187.

Jamblici Sal. See the article Jamblici fal.

Sal lucidum, in natural hiftory, a name given by fome to nitre. Others ufe the phrafe to exprels the nitre of the antients, that is the natrum.

Sal ynarinus, in ichthyography, the name of a truttaceoug iifh of the umbla kind, and very much approaching to that fpecies called the reuiele. See Reutele. And by fome fufpected not to be efTentially different from that fpecies. It is a very fcarce fifn, and is extremely valued for the table, but is never caught in any plenty, never keeping in fhoals as many other fifties, but living fingly. It loves clear ftony

1 rivers of a {harp.. current, and feeds on fmall fifli. Its moft frequent fize is of about a pound weight, and it very rarely

• exceeds