Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/398

 SAL

SAL

exceeds twice that. Its tail and fins are very red ; its fides and belly reddiib, and its back of a fort of orange colour or reddifh yellow, having fome yellow fpots. Its fcales are moderately large, and do not eafily fall off on rubbing. The fal mar'mus is diftinguifhed by Artedi by the name of the forked tailed falmon, with a yellowifh back, and with yellow fpots. See Salmo.

Sal marinum regeneratum, in chemiftry, the name given to a feajalt, produced by adding an alkali to its acid fpirit of fait drawn by diftillation. The procefs is thus, dilute four ounces of oil of tartar, with three times its weight of fair water ; put this mixture into a tall glafs body, and heat it, and drop into it any of the kinds of fpirit of fea_/o/f, whe- ther Glauber's, or that prepared with bole ; make the vef- fel now and then, and continue to drop in the acid till the alkaline liquor is fated, and there riles no more effervefcence ; filter the liquor, and evaporate to a pellicle, and fet it by to cryftallize, and there will be procured cryftals of perfect fea fait, in all things agreeing with common fait. Boevb. Chem. Part II. p. 253.

Sal mortis-, fait of iron, a chemical preparation, which is made as follows : mix together a quart of water and eight ounces of oil of vitriol ; pour the oil of vitriol in by a little at a time ; and having put this mixture into a glafs veflel, add to it filings of iron, four ounces. When the ebullition is over, evaporate the liquor to a pellicle, and fet it to fhoot ; there will be found a green vitriol or fait in fair cryftals, which dry for ufe.

This fait is one of the moft powerful preparations of iron ; it opens obstructions of all kinds, and ftrengthens the vif- cera; it is an excellent medicine in cachexies, obftructions of the fpleen and liver, and in fuppreffions of the menfes; it is alfo found good againft worms.

The beft manner of giving it is in folution, half an ounce 'in a quart of water, four ounces of which is a dofe ; and if drank in the manner of the natural chalybeate waters, it will be found to exceed moft of them in its good effects.

Sal mtrabik, Glauber's fait s. Though this be a well known preparation, and the refult of a mixture of a vitriolic acid with marine fait, and the world has fuppofed it could be no other way found than by fuch an union made by art ; yet Mr. Heliot has communicated to the academy of fciencesof Paris, an account of its being found in vitriol alone, with' out the addition of any foreign matter. The common green vitriol or copperas is well known to be made in England, by an union of the fulphureous acid of the common pyrites, and iron. Old iron is thrown into large quantities of a folution of the pyrites, that it may be difiblved, and the union produces a concrete in the form of a regular fait. This fait we well know contains a fulphureous matter } whether that be obtained from the py- rites, or from the iron that enters its compofition ; fince, in the diftillation of its oil, there ever efcapes a very ftrong and penetrating, fcent of fulphur through the junctures of the veffels.

There are alfo fome vitriols, particularly the common Swe- dish kind, which may very probably be aluminous ; fince the yellow fhining gold like marcafite from which it is made, yields in its native ftate true fulphur in diftillation, and af- terwards affords vitriol in the lixivium, after the remainder has been long expofed to the air, and finally it yields alfo alum by the addition of urine and pot-afhes, to what they call the mother water of vitriol.

Mr. Lemery has fhewn, that after a moderate diftillation of green vitriol, a fait of the nature of alum may be drawn by a lixivium from the colcothar ; and befide this, Mr. He- liot has found in that colcothar a vitrihable earth, and a genuine Glauber's fait. Thofe who are at all acquainted with chemiftry, know that Glauber's fait is a concrete compofed of the vitriolic acid and fea/fl/r, and it is generally received as a certainty that any other acid joined to {en fait cannot afford this concrete ; therefore if Glauber's fait is to be pro- duced from fea fait alone, and yet is proved to be found in pure vitriol j it muft follow, that pure vitriol does contain fea fait, or at leaft that fubftance which is the bafts of fea fait : and this will prove a lefs fingular obfervation, if it can be evinced, according to Becher, that all the known falts owe their origin to marine fait.

Mr. Lemery, in order to procure his aluminous fait from vitriol, does not pufh his diftillation too far, that the acid may remain engaged and entangled in that earth, by the union with which it is to form this fait, which is afterwards to be feparated by lixiviation ; but Mr. Heliot pufties the diftillation to the utmoft degree with a violent fire of three or four days and nights, fuch as Kunkel prefcribes, for the diverting vitriol of all its acid, that the remainder in the re- tort may contain little or no fait at all. He took eighteen pounds of Englifh vitriol, which he calcined to a rednefs, and by that means reduced it to fix pounds. This quantity, though put in a covered earthen veflel, acquired nine ounces in weight from the humidity of the air in two days ; and in this ftate it was put into a german retort, and urged to that degree by the violence of fire, for fo long a continu- ! ance, that the remaining black mafs, though treated with

all the care imaginable, and wafhed by repeated lixiviation, yielded only two ounces and a half of fait, and that of a very earthy kind. About nine ounces of phlegm had been feparated at the beginning of the diftillation, but when the white vapours began to appear, the veffels were all clofed and fo kept to the end of the operation ; the produce of which was an icy oil cf vitriol, which was found in a black cryftalHne form.

The fuccefs of the operation, as to the procuring this Icy oil of vitriol, depends on the nice luting the junctures of the veflels, fo as to prevent all communication with the external air ; for other wife the vapours attract a moifture from the air, which renders them fluid in the receiver. The receiver muft alfo be placed at a ccnfulerable diftance from the retort, that it may be cool enough to condenfe the vapours, and large enough to prevent their exploding, for want of room ; for though the preceding calcination has carried oft the more volatile parts, yet there remains matter enough for great explofion, and for the formation of a fub- ftancc not lefs inflammable, than crude fulphur, were the acid in a lefs proportion.

The beft method is to fit to the neck of the retort a receiver with two necks ; the one of which receives that of the re- tort, and the other is received into a capacious fingle re- ceiver of the common kind.

The icy oil is not eafily got out of the receiver, for it ex- hales fo ftrong a fulphureous vapour, that if it be placed lower than the operator's head, it would fuffocate him in a moment.

This icy oil is black, becaufe.it carries over with it a quantity of that oily matter, which no vitriol is ever entirely free from, and which is always found in the mother water, as it is called, of vitriol, after the repeated cryftallifations of the fait from It.; and it is well known, that any inflammable fubftance, in ever fo fmall a quantity, will turn the pureft oil of vitriol black ; nor is this all, for the acid fpiiits alfo, when urged by a violent fire, carry over with them iron, or at leaft fuch particles, as are capable of becoming iron. This is eafily demonftrated in either the common or the blackifh cryftals of the icy oil of vitriol j for if thefe be diflblved in a large quantity of pure diftilled water, and allowed to ftand feven or eight days, there always precipitates to the bottom of the veflel a fediment, which, after it has been calcined, has many particles, which readily anfwer to the magnet.

Befides this oily matter, and thefe particles of iron, the oil of vitriol carries with it alfo a white, heavy, and cryftalline fubftance, of the nature of earth, which may be feparated, by means of fpirit of wine, from oil of vitriol, ever fo well rectified. The fame fort of earth is alfo found in the fait, which is extracted from the caput mortitum, left after the di- ftillation of the icy oil. The lixivium made by this au- thor from the remaining mafs, left after the diftillation of the icy oil of vitriol, was expofed to the air, in a glafs cu- curbit, for the fpace of fix months ; and the faline liquor, concentrated by evaporation in a fand-heat, became green, and would by no means cryftallize. The firft faline pellicles had a faline, but earthy tafte : thefe precipitated by degrees of themfelves, and were finally fuccecded by others, which taftcd acid, but not greatly fo. This liquor being evaporated to a drynefs, an ounce of the remainder was put into a re- tort, and four ounces of oil of vitriol was put on it, with one ounce of water, to forward the diflblution ; this was kept in digeftion twenty days, at the end of which time the liquor acquired a green colour, which (hewed. that there were yet in the mafs metallic parts for it to "diflblve : this was finally diftilled with a gentle heat, to feparate the phlegm, and afterwards the fire was encreafed, to drive over the acid; the oil of vitriol came over as ftrong, as it was when put on, but much more fulphureous. The diftilled oil being returned upon the fait, with the frefh addition of a fmall quantity of water, became fo hot, that the veflel could not be held in the hand; which had not been the cafe in the firft mixture, at leaft not in any fenfible degree. Se- veral more cohobations made it yet more and more acid, and at length it became fo cauftic, as to leave an efchar on being juft touched upon the tongue.

The green colour, which the acid firft received, became at length changed into a blue one, which gave fufpicion that there was copper, as well as iron in the vitriol. This might appear ftrange, as it was Englifh vitriol that was ufed ; but Kunkel has proved by experiments, that there is fome cop- per in all vitriol, even in the Englifh ; nay he advances, that in the vitriol of iron, made with oil of vitriol and filings of that metal, there may always be difcovered fome fmall portion of copper; and, in fine, that there is no iron but contains fome portion of copper, and no copper but con- tains fome portion of iron.

After the iixth cohobation of this blue liquor, there re- mained a granulated and filamentous faline fediment, on the furface of which there was a fmall quantity of a yellow fublimation, refembling flower of fulphur ; warm water be- ing poured upon this matter, became of a greenifh colour ; and this being digefted in a fand-heat, became afterward* 3 reddiih,