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Book III.

Grains to halfVehicle.

a Dram in

Of Nitre Vitriolated.

Vitriolated Nitre is made of Salt of Nitrediffolv'd in Spirit of Vitriol, and thenprepat'd; and to which is attributed the fameQualities as to the vitriolared Tartar. Note,It ought to be white, light, and in fmallStriae or Needles, like Sal Saturni.

There is alfo a Sort of Butter prepar'd ofNitre, by the Means of Tartar ; the Pro-cefs whereof may be feen in Monfieur Cho-rus's Chymiftry, p. 853.

x$. Of Natural Borace.

TTHE Natural Borace, to which the An-•*• cients have given the Name of Cbryfocolla, or lineal, is a Mineral Salt of theFigure of the common Sal Gem, found inthe Bowels of the Earth in many Places ofPerfia; and at the Bottom of a Torrent, a-mong the Mounrains of Purbeth, in theCountry of Rad^ioribron, that reaches to theConfines of the white Tartary. When thisMineral is taken out of the Earth it is ex-pos'd to the Air, that it may contract a Sortof fat reddifh Ruft, which nourishes and pre-ferves it from being calcin'd, as it were bythe Influence of the Weather; and when itis as it ought to be, the Perfians carry it forthe moft Part to a Place cali'd Amadabat, fromwhence the Englifb, Dutch, and We have it;and this is what we call Natural Borace, ortheunpoliih'd, rough, fat Borace, which fomeWorkmen imploy for the fame Ufes as theydo the refin'd.

We have another Sort of Natural Boracebrought us, which differs only from the For-mer in that it is a little dryer, and of

Of MINERALS. ffj

any agreeable Dutch make that which they fend as underthe Appellation of refin'd Borace.

The Ancients were not out when they faidthere was a greenifli Natural Borace, of theColour of a Leek, no more than Agricola,who rightly enough obferves, that he hadfeen a Foflil Nitre, folid and hard, like aStone, of which the Venetian Borace is made :But the fame Author is very much miftaken,when he fays, that then no Borace was in ufebut the Factitious or Artificial, made of theUrine of Boys that drank Wine, Brafs Ruft,and fometitnes Nitre beaten together in aBell-metal Mortar to the Confluence of anOyntment ; which is far from Truth, iincethe Borace he means is only the fat Borace re-fin'd and (hot into Cryftals.

Borax, -Chry'focolla; Capifirum Auri,Auricolla, or Gold Flux Powder, is Lemery,a Mineral Salt that has the Colourand Tranfparency of Sal Gem, but a great dealmore Pungency ; it is found in certain Minesof Perfia, and feveral other Places: Whenthey take it from the Earth they expofe it tothe Air, where it becomes grealy and reddifhon its Superficies ; this is that which is cali'dFat Borace. This fat hinders the Salts thatthey cannot be penetrated and diffolv'd, ormelted by the Air; there is likewife found *grey or greenifh Borace, which Colours pro-ceed from the various Impreflions, that theAir being hotter or colder, makes upon theSalt, by opening it more or lefs.

The Venetians and Dutch purifie or refinetheir Borace as they do other Salts, by dif-folving in Water, filtrating the Diflblution,leaving it afterwards to evaporate, and fet-tling it to cryftallize. They bring us this Boraceunder the Name of Borace refin'd. Cbufeyour Borace in fine whire Pieces, neat, cry-ftalliz'd and tranfparent. One may, by Re-fining, feparate from Borace a virriolick Mat-ter, which gives it a great deal of Sharpnefs j

""■• "* iu<»v 11 is a. iivnv uiji.1, aim t>i a. ici, wuii.li j;ivc» n a great ueai ot jnarpnels ■

grey Colour, which proceeds only from its for which Reafon the Refin'd Borace is much

having been longer expos'd to the Air, fofter than the Natural, and ought to be

whereby the reddifh fat Subftance, —'---- — r ~' J -'- »*- J! --•■•■-

.__ j ....___....._. ________, where

with 'tis covered becomes dry, and like to theEnglifh Copperas that has lain a great Whileabove Ground. Thofe that have Occafionof one Sort or 'tother mult take Care that it benot mix'd with itones, or other fuch Refufe,as it frequently happens to be. 'Tis of eitherof thefe Sorts of Borace the Venetians and

prefer'd in Medicine ; it is incifive" and pe-netrating, proper to open the OMru&ions ofthe Glands of the Mefentery, and diflblvethe Schirrus of the Liver and'Spleen. TheDofe is from four Grains to twenty. Theyalio ufe it externally to confume the Excre-fcencies of Flelh. They may draw a Spiritfrom Borace like that of Alum, by a veryX z ftrong