Oil of Myrcia.

Botanical name: 

Oil of Myrcia. N. F. IV. Oleum Myrciae. Oil of Myrcia. Oil of Bay.—"A volatile oil distilled from the leaves of Pimenta acris Wight (not Myrcia acris DC.) (Fam. Myrtaceae)." This oil, formerly official in U. S., 1890, is now official in the National Formulary IV.

"A volatile oil distilled from the leaves of Pimenta acris (Swartz) Wight (Fam. Myrtaceae). Preserve it in small, well-stoppered, amber-colored bottles, in a cool place, protected from light." N. F.

The commercial oil of bay is a mixture of both heavy and light oils, as G. M. Beringer found the specific gravity of two samples of undoubted purity to be 0.975 and 0.994. (A. J. P., 1887, 286.) Mittmann (A. Pharm., 1889, 529) reported the following constituents: 1, pinene; 2, possibly dipentene; 3, a polyterpene, probably diterpene (insoluble in alcohol); these three in small quantity only; 4, eugenol, the chief constituent; and, 5, methyl-eugenol, in smaller quantity. It has since been examined (March, 1895) by Power and Kleber, who state that it contains from 60 to 65 per cent. of phenols, of which two were identified: eugenol, C10H12O2, and chavicol, C9H10O; two phenol esters, methyl-eugenol, C11H14O2, and methyl-chavicol, C10H12O; phellandrene and a newly discovered terpene which they named myrcene, C10H16, and citral, C10H16O. (Ph. Rund., 1895, 60.) The oil is officially described as "a yellow or brownish-yellow liquid having a pleasant, aromatic odor and a pungent, spicy taste.

"With an equal volume of alcohol, glacial acetic acid, or carbon disulphide, it yields slightly turbid solutions. An alcoholic solution is slightly acid to litmus paper.

"Specific gravity: 0.962 to 0.990 at 25° C. (77° F.).

"It is laevorotatory, the angle of rotation not exceeding -3°, in a 100 mm. tube, at 25° C. (77° F.).

Oil of bay is not used internally, but solely for making bay rum. (See Spiritus Myrciae Compositus, Part III.) For a paper describing the manufacture of bay rum and oil of bay, see W. O. Fishlock, C. D., 1912, 714.

For an English formula for bay rum, see P. J., 1896, 468.

The oil of bay is an active antiseptic, 1 part in 1000, according to Peck (J. A. M. A. 1899, xxxii, p. 6) being sufficient to prevent the growth of bacteria.

Bay rum is used chiefly as a refreshing perfume in cases of nervous headache, faintness and other nervous disorders, either held to the nostrils, or applied on soft linen to the head and forehead. According to Berger (Th. M., 1907, xxi, p. 221) it is a valuable local application in various diseased conditions of the skin, especially in seborrhea of the acalp. It is also grateful to the feeble and convalescent patient, by being sprinkled on the bed covering or otherwise made to impregnate the air of the chamber. The oil of bay is often adulterated, and is frequently sold by smugglers.

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