Origin. - A volatile oil distilled from the fresh leaves and twigs of Melaleuca leucadendron L., a tree with crooked stem and scattered branches, resembling the weeping willow, indigenous in the East Indies. It should yield not less than 55 per cent. by volume of cineol.

Description and Properties. - A light, thin, bluish-green, or, after rectification, colorless liquid, having a peculiar, agreeable and distinctly camphoraceous odor, and an aromatic, bitterish taste. Specific gravity, 0.925 at 25 C. With an equal volume of alcohol it affords a clear solution, which either has a slightly acid reaction or, in the case of the rectified oil, is neutral to litmus-paper.

Constituents. - The chief constituent is cineol.

Dose. - 1-5 minims (0.06-0.3 Cc.) [8 minims (0.5 Cc), U. S. P.].

Physiological Action and Therapeutics are identical with those of the oil of cloves.