RES

RES

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colour, very fragrant, and of a (lightly bitterand acrid tafte. Its chemical properties clofelyrefemble thofe of the lad mentioned fpecies,and it is only mentioned in this place on ac-count of the extravagant value which theTurks fet upon it, which is far beyond that ofall the other aromatics.

4. Balfam of Peru . This is a dark brownbalfam of the confidence of thin honey ob-tained from the Myroxylon Peruferum (as it isfaid) by boiling the twigs and bark in water,and when cold, the balfam fwims at the top ofthe liquor and is (kimmed off. There appearsto be two fpecies of this balfam, the white andthe brown , but the latter is the only one com-monly known.

This juice has a very fragrant fmell andpungent tade. It is entirely immifcible withwater and with the fixed oils, but diffolves inthe eflential oils and in alcohol. When thisbalfam has long remained at red in any veffel,it depofits crydals, from which the benzoicacid may be obtained by fublimation.

By didillation with water this balfam yieldsTe * ts weight of an eflential oil, of a reddifhcolour, and a pungent tade. This oil probablyalfo contains benzoic acid. When compleatlycharred by fulphuric acid, Mr. Hatchett found100 grs. to yield 64 grs. of mere charcoal. Acompound tincture of this balfam forms thecommon Friar’s Balfam, ufed as an applicationin cuts and flight wounds.

5. Balfam of Tolu. This juice flows fromincifions made in the trunk of the ToluiferaBalfamum, a large tree refembling the pine,which abounds in the province of Tolu, inSouth America . It is of a yellowifh browncolour, and, when frefh, of a thick tenaciousconfidence, but by age it hardens fo as to bemoderately brittle in cold weather.

This balfam has a mod fragrant fmell, morefo than mod of the refins, fomewhat refem-bling lemons. When chewed it clings to theteeth, and at fird gives very little tade, but aftera time it leaves an agreeable pungency in themouth. When kindled it burns with a copiousflame and fmoke (like all the other refins) butthis is accompanied with a very pungent fra-grant vapour which excites coughing, and isowing to the volatilization of the benzoic acidthat this balfam contains in feme abundance,t rough in ^ much lefs proportion than thegum benzoin. When this balfam is boiledwith water it melts, and fettles at the bottom ofthe veiiel, and appears to remain there unal-tered, but the water without loling its tranf-

parency becomes highly fragrant and pungent,and contains a notable quantity of benzoicacid. This acid may alfo be procured from itby the fame methods by which it is extractedfrom the gum Benzoin, as deferibed under thatarticle.

Balfam of Tolu is totally foluble in alcohol,and it is entirely feparated from this men-ftruum (the benzoic acid excepted) by water.If the folution is not too concentrated this pre-cipitated balfam remains for a time fufpendedin the liquor and gives it a milky appearance.By diftillation this balfam yields an eflential oiland benzoic acid. A hundred grains of thebalfam charred by fulphuric acid, gave fifty-fourgrains of charcoal.

6. Liquidambar, or Liquid Storax. This is arefinous juice, which flows from the trunk ofthe Liquidambar Styracifua, a tree refemblingthe maple, found in Virginia and Mexico . Thisbalfam is of the confidence of. honey, reddifhbrown, nearly tranfparent, of an acrid un£lu-ous tafte and a fragrant fmell. It is feldomfeen, and has not been much examined.

Solid Resins.

7. Gum Anime. This refill, which is veryrarely met with, exfudes from the trunk of theHymenaa Courbaril , a large tree growing inBrazil and New Spain. It is brought overeither in fmall roundifh tears, or in largermaffes, with the furfaces covered with a whitepowder. The colour is yellowifh white andpellucid, it is very brittle, and gives a fhiningfra£Iure. It refembles copal in appearance, butis readily diftinguiihable from it (among otherthings) by being eafily and totally foluble inalcohol, which copal is not, without much dif-ficulty and particular management. This refinhas very little tafte. It is infoluble in water,but forms a grateful yellow tinfture with alco-hol, which has a bitterifh pungent tafte. Dif-tilled with water it gives a very fmall quantityof eflential oil. The natives of the countrieswhence it is procured chew it, but it is neverufed in Europe .

8. Benzoin. This refin, which contains moreof the benzoic acid than any other fubftance,has already been deferibed under this article.

9. Dragon’s Blood. The origin of this va-luable refin is not precifely known, but itappears to be obtained from feveral large treesgrowing in many parts of the Eaft Indies andthe Indian Archipelago, of which the moftknown are the Calamus Rotang, and PterocarpusDraco. This refin is very largely mixed andadulterated fo that the famples to be found in

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