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580

General Bifiory o/DRUGGS.

Vol. If.

ftrong Fire; it is aperitive, and very likeSpiritof Sale: It is call'd Cbryfo-colla, Gluten Auri,Capiftrum Ami, and Auri-colla, becaufe theGoldfmiths ufe it to flux Gold withal.

Of RehVd Borace.

As Natural Borace is found of dif-Pomet. ferent Colours, fometimes greenifh,and other While yellowifh, the Ve-netians, who were the firft that brought Bo-race into Vogue, finding it cou'd not be wellmade ufe of with its natural Fatnefs andUn&uofity, confider'd of a Way of purify-ing of it, by diffolving it in Water ; thenfiltrating and cryftallizing it, in order towhich they made ufe of Cotton Matches,upon which the Borace is cryftalliz'd, after thefame Manner as Sugar Candy or Verdigrifedoes on Sticks or Splinters of Wood.

As for others that don't ufe Cotton, theyreduce the Borace into little Stones of theForm and Figure of the Tag of a Lace orPoint; but as this Sort of Borace had agreenifh Caft, the Dutch has taken it to Task,and made it whiter and more vendible, andreduce it into larger Pieces, whicn is whatwe fell at this Day.

Borace, whether it be the Venetian, orthat of Holland, ought to be chofen clear andtransparent, of Tafte almoft infipid, takingCare that it be not mix'd with Englifio Alum,which is difficult enough to difcover , if theAlum has been foak'd in Water, and thenexpos'd a few Days to the Air, to give it thenatural rough Appearance of Borace ; but thisCheat may be eafily found out, if you'll putit to the Teft : For firft it will by no Meansfolder Metals, nor being put upon lightedCharcoal will it fwell and heave like Borace,or is it ever altogether fo white or light.

Refin'd Borace is much in Ufe by a greatmany Sorts of Workmen, and ferves as wellto folder, as to melt and diflblve Merals:Some ufe it alfo in Fucus's; 'tis of fome fmallUfe too in Medicine, fince'tis an Ingredientof the "Ung, Qitrinum, &c.

l6. Of Alum.

Pomet. ALum is a Foflil Salt drawn from

-^ Stones of different Bignefs and

Colour in feveral Parts of Eurofe, efpecially

in Italy, England, and in France. After Alumis taken ouc of its Bed or Quarry, as youtake other Stones, it is burnt in a Kiln madeon purpofe as you do for Lime, or the like ;and wnen it is calcin'd, its Salt which is theAlum is drawn out with Water, proceedingafter the fame Manner as in making Saltpe-tre. A certain Perfon in the World, in thePrefence of a Man of Worth, maintainedthat Urine was made ufe of inftead of Wa-ter in drawing this Salt; but fince his Autho-rity was not fufficient to make him credited ,I chufe rather to reft fatisfied with what Mat-thiolus, upon Diafcorides, has written of it,who having been an Eye Witnefs of the Fact,has given us an ample Defcriprion of it inhis Book, p. 733, to which my Reader mayhave Recourfe.

We commonly fell fix Sorts of Alum, towit, the plumous Alum, or Earth Flax ; theRoman, Englifh, Liege, Burnt Alum, andthe Sugar Alum ; as for the round Liquidand Black Alum I know nothing of it.

Alumen, or Alum, is an acid mi-neral Salt, made from a Kind of Lemery.Stones of different Sizes and Co-lours, which are found in the Quarries ofFrance, Italy and England: They calcinethis Stone, and then make Alum of it bySolutions, Filiations' and Coagulations, asthey make Saltpetre ; there are feveral Sortsof it, as Roman Alum, Roch Alum, and Su-gared Alum.

The Roman Alum, or that of Civita Vec-chia, call'd Alumen Romanum, is a Salt inStones of a moderate Size, that are reddifhwithin, of an acid ftiptick Tafte ; they ufe itoutwardly for flopping of Blood, and in-wardly in Gargarilins for Inflammations ofthe Throat, and to clean the Teeth : Theydry it or calcine it upon the Fire to free itfrom its Flegm, then it is call'd Burnt Alum ;this is an Efcharotick, and ferves to eat a-way proud Flefh, diffolve Excrefcencies,and open Ulcers and Chancres.

Roch Alum, White, or Englifh Alum, call'dAlumen Rupeum, or Rock. Alum, is a Salt inlarge great Lumps, that are clear, white, andtranfparent as Cryftal, which is broughtfrom England, this Alum has the Virtues ofthe former, but is not fo ftrong. The Dyers,&c. ufe it. The Alum, call'd Alumen Suc-carinum, or Sugar Alum, is a Compofition

made

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