Dragon's Blood.

Dragon's Blood. Sanguis Draconis. Sang-dragon, Fr. Drachenblut, G. Sangre de drago, Sp.—Dragon's blood, of which there are several commercial varieties, is a resinous exudation obtained from the fruits of a number of palms. East Indian dragon's blood is obtained from a number of species of Daemonorops, a genus which was previously ascribed to Calamus. Malay dragon's blood is obtained from Daemonorops didynophyllos, D. micranthus and D. propinquus; Sumatra dragon's blood from Daemonorops Draco Blume (Calamus Draco Willd.). In Borneo a dragon's blood is obtained from Daemonorops draconcellus and other species of Daemonorops. On the surface of the fruit, when ripe, is an exudation, which is separated by rubbing, or shaking in a bag, or by exposure to the vapor of boiling water, or finally by decoction. The finest resin is procured by the two former methods. It comes in two forms: sometimes in small oval masses [tear dragon's blood) of a size varying from that of a hazelnut to that of a walnut, covered with the leaves of the plant, and connected in a row like beads in a necklace; sometimes in cylindrical sticks, eighteen inches long and from a quarter to half an inch in diameter, thickly covered with palm leaves, and bound round with slender strips of cane. See paper by E. M. Holmes in P. J., 1905, 933.

Dragon's blood is inodorous and tasteless, insoluble in water, but soluble in alcohol, ether, and the volatile and fixed oils, with which it forms red solutions. According to Herberger, it consists of 90.7 parts of a red resin, which he calls draconin, 2.0 of fixed oil, 3.0 of benzoic acid, 1.6 of calcium oxalate, and 3.7 of calcium phosphate. Tschirch (Harze und Harzbehälter, 1900, p. 189) has made an elaborate study of dragon's blood, and finds 2.5 per cent. of draco-alban, C₂₀H₄O₄, a white substance melting with decomposition at about 200° C. (392° F.); 13.58 per cent. of draco resen, a yellow resinous substance of the formula C₂₆H₄O₄, and 56.86 per cent. of draco resin, a resin ester or mixture of esters, benzoic dracoresinotannol ester and benzoylaceticdraco-resinotannol ester, and 18.4 per cent. of insoluble substances. It was formerly employed in medicine as an astringent, but is nearly or quite inert, and is now never given internally. It is sometimes used to impart color to plasters. For further information concerning this drug, see U. S. D., 19th ed., p. 1475.

The Dispensatory of the United States of America, 1918, was edited by Joseph P. Remington, Horatio C. Wood and others.