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17.2.11
A Dictionary of Arts: Balsams.
A Dictionary of Arts, Manufactures, and Mines; containing A Clear Exposition of Their Principles and Practice
by Andrew Ure, M. D.;
F. R. S. M. G. S. Lond.: M. Acad. M. S. Philad.; S. PH. DOC. N. GERM. Ranow.; Mulh. Etc. Etc.
Illustrated with nearly fifteen hundred engravings on wood
Eleventh American, From The Last London Edition.
To which is appended, a Supplement of Recent Improvements to The Present Time.
New York: D Appleton & company, 200 Broadway. Philadelphia: George S. Appleton, 148 Chestnut St.
MDCCCXLVII
1847
BALSAMS (Baumes, Fr. Balsame, Germ.) are native compounds of ethereal of essential oils, with resin, and frequently benzoic acid. Most of them have the consistence of honey; but a few are solid, or become so by keeping. They flow either spontaneously, or y incisions made from trees and shrubs in tropical climates. They possess peculiar powerful smells, aromatic hot tastes, but lose their odoriferous properties by long exposure to the air. They are insoluble in water; soluble, to considerable degree, in ether; and completely in alcohol. When distilled with water, ethereal oil comes over, and resin remains in the retort.
1. BALSAMS WITH BENZOIC ACID:-
Balsam of Peru is extracted from the myroxylon peruiferum, a tree which grows in Peru, Mexico, &c.; sometimes by incision, and sometimes by evaporating the decoction of the bark and branches of the tree. The former kind is very rare, and is imported in the husk of the cocoa-nut, whence it is called balsam en coque. It is brown, transparent only in thin layers, of the consistence of thick turpentine; an agreeable smell, an acrid and bitter taste; formed of two matters, the one liquid, the other granular, and somewhat crystalline. In 100 parts, it contains 12 of benzoic acid, 88 of resin, with traces of a volatile oil.
The second sort, the black balsam of Peru, is much more common than the preceding, translucent, of the consistence of well-boiled sirup, very deep red-brown color, an almost intolerably acrid and bitter taste, and a stronger smell than the other balsam. Stoltze regards it as formed of 69 parts of a peculiar oil, 20-7 of a resin, little soluble in alcohol, of 6-4 of benzoic acid, of 0-6 of extractive matter, and 0-9 of water.
From its high price, balsam of Peru is often adulterated with copaiba, oil of turpentine and olive oil. One thousad parts of good balsam should, by its benzole acid, saturate 75 parts of crystallized carbonate of soda. It is employed as a perfume for pomatums, tinctures, lozenges, sealing-wax, and for chocolate and liqueours, instead of vanilla, when this happens to be very dear.
Liquid amber, Storax or Styrax, flows from the leaves and trunk of the liquid amber styraciflua, a tree which grows in Virginia, Louisiana, and Mexico. It is brownish ash-gray, of the consistence of turpentine, is brownish-red, dries into a yellowish or reddish brittle resinous mass, of a smell like benzoin; is soluble in alcohol and ether; affords, with water, benzoic acid.
Balsam of Tolu flows from the trunk of the xnyrozylon toluiferum, a tree which grows in South America; it is, when fresh, of the consistence of turpentine, is brownish.red, dries into a yellowish or reddish brittle resinous mass, of a smell like benzoin; is soluble in alcohol and ether; affords, with water, benzoic acid.
Chinese varnish flows from the bark of the Augia sinensis; it is a greenish yellow turpentine-like substance, smells aromatic, tastes strong and rather astringent, in thin layers dries soon into a smooth shining lac, and consists of resin, etherous oil, and benzoic acid. It is soluble in alcohol and ether; and has been employed, immemorially, in China, for lackering and varnishing surfaces, either alone or colored.
BALSAMS WITHTOU BENZOIC ACID:-
Copaiva balsam, balsam of copachu or capivi, is obtained from incisions made inthe trunk of the Copaifera officinalis, a tree which grows in Brazil and Cayenne. It is pale yellow, middling liquid, clear transparent, has a bitter, sharp, hot taste; a penetrating disagreeable smell; a specific grafity of from 0.950 to 0.996. It dissolves in absolute alcohol, partially in spirit of wine, forms with alkalis, crystalline compounds. Its consists of 45.59 ethereous oil, 52.75 of a yellow brittle resin, and 1.66 of a brown viscid resin. The oil contains no oxygen, has a composition like oil of turpentine, dissolves caoutchoue /according to Durand), but becomes oxydized in the air, into a peculiar species of ressin. this balsam is used for making paper transparent, for certain lackers, and in medicine.
Mecca balsam, or opobalsam, is obtained both by incisions of, and by boiling, the branches and leaves of the Balsamodendron Gileadense, a shrub which grows in Arabia Felix, Lesser Asia, and egypt. When fresh it is turbid, whitish, becomes, by degrees, transparent; yellow, thickish, and eventually solid. It smells peculiar, but agreeable; tastes bitter and spicy; does not dissolve completely in hot spirit of wine, and contains 10 per cent. of ethereous oil, of the specific gravity 0.876.
Japan lac varnish flows from incisions in the trunk of the Rhus Vernix (Melanorrhau usitata) which iscultivated in Japan, and grows wild in North America. The juice becomes black in the air; when purified, dissolves in very little oil; and mixed with coloring matter, it constitutes the celebrated varnish of the Japanese.
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