Obs. This oil, like that of bitter almonds, does not pre-exist in the seed, but is the result of the action of myronic acid on a peculiar substance, myrosin, in the presence of water. Oil of black mustard has been used as a stimulant or counter-irritant in palsy, &c.; and the distilled water, or a solution of the oil in water, is said to be an excellent and cleanly remedy for the itch.
Oil of Myrrh. Syn. Oleum myrrhæ, O. m. essentiale, L. Colourless; thin; heavier than water; stimulant; smells strongly of the drug.
Oil of Myr′tle (Volatile). Syn. Essence of m.; Oleum myrtæ essentiale, L. From the flowers and leaves of Myrtus communis. 100 lbs. of the fresh leaves yield 21⁄2 to 5 oz.
Oil of Namur Grass. See Oil of Grass (Namur).
Oil of Narcis′sus. Syn. Essence of jonquil; Oleum narcissi, L. As OIL OF JASMINE. Delightfully odorous.
Oil of Nero′li. See Oil of Orange flowers.
Oil of Nut′meg (Volatile). Syn. Oleum myristicæ (B. P., Ph. E.), O. m. moschatæ (Ph. D.), L. From the officinal nutmeg or kernel of the fruit of Myristica moschata. Nearly colourless; odour and flavour that of the fruit, but more powerful. By agitation with water, it is separated into two oils—one lighter, the other heavier, than water; the last is butyraceous. Sp. gr. ·948. Prod. 41⁄2 to 7%. It is reputed to make the hair grow, and to prevent baldness.
Oil of On’ions. From the bulbs of Allium
cepa, or common onion. Contains sulphur, and smells strongly of the herb.
Oil of Or′ange. Syn. Essence of o.; Oleum aurantii, O. aurantiorum, O. a. corticis, L. From the yellow portion of the rind of either the Seville or sweet orange, preferably of the last; as oil of bergamot or lemons. Closely resembles oil of lemons, but is more agreeably fragrant. The expressed oil is very apt to become opaque, and deposit a stearopten, especially in cold weather, unless well kept from the air. Sp. gr. ·875. Prod. 100 fruits yield 4 to 5 oz. (See below.)