DRAGON'S BLOOD, sometimes called gum dragon, an astringent, resinous substance, obtained from several trees of different natural orders, natives of warm countries. The greater part of the D. B. of commerce is probably the produce of pterocarpus draco, a large South American tree of the natural order leguminoste, suborder papilionaceoe, which at some seasons appears as a magnificent mass of yellow blossom. A similar substance is yielded in the East Indies, by the red sandal-wood tree (pterocatpus santalinus); and dalbergia monetaria, a tree of the same order, yields it in Guiana. Mexican D. B., used in Mexico as a vulnerary and astringent, is obtained from croton draco (see CROTON), of the natural order euphorbiacete. The best kind of all is supposed to be produced by cal autos draco, an East Indian palm, and part of it is said to be obtained from the fruit of the palm.—D. B. exudes from the surface of the leaves, and from cracks in the stem of the DRAGON TREE (draccena draco), a tree of the natural order liliacece, remarkable for the sizc.which it sometimes attains, rivaling even the baobab, and of which a celebrated specimen near Orotava, in the island of Teneriffe, was found by Humboldt in 1799 to have a stem about 45 ft. in circumference, and is described as having been of similar
gigantic size in the beginning of the 15th century. The stem of the dragon tree is, how ever, generally short in proportion to its thickness, and its head consists of numerous, short branches, terminating in tufts of sword-shaped leaves. It is not supposed to yield any of the D. B. of commerce.
D. B. is opaque, of a deep reddish-brown color, brittle, smooth, with a shining shell like fracture, and when burned, emits an odor resembling that of benzoin. It is nearly insoluble in water, but is soluble in alcohol, and the solution will permanently stain heated marble, for which it is often used. as well as for staining leather and wood. It is also soluble in oils and turpentines, and enters into the composition of brilliant and much-esteemed varnishes. It was formerly employed in medicine, but is now almost out of use.—An astringent resin obtained from the eucalyptus resinifera of Australia is there called dragon's blood.