This section is from the book "Materia Medica And Therapeutics: An Introduction to the National Treatment of Disease", by John Mitchell Bruce. Also available from Amazon: The pharmacology and therapeutics of the materia medica.
The seed of the sweet almond tree, Amygdalus communis, var. dulcis. Cultivated about Malaga.
Characters. - Above an inch in length, Lanceolate, acute, with a clear cinnamon-brown seed-coat, and a bland sweetish nutty-flavoured kernel. Does not evolve the odour of bitter almonds when bruised with water.
Impurity. - The bitter almond, which yields an odour of hydrocyanic acid when bruised with water.
Amygdala Amara - Bitter Almond. - The seed of the bitter almond tree, Amygdalus communis, var. amara. Brought chiefly from Mogadore.
Characters. - Resembles the sweet almond in appearance, but is rather broader and shorter; has a bitter taste, and when rubbed with a little water emits a characteristic odour.
Composition. - Both varieties of almond yield by expression about 50 per cent. of fixed oil, Oleum Amygdalae, and albuminous substances, including emulsin. The bitter variety also yields, by distillation with water, a volatile oil, Oleum Amygdalae Amara, Essential Oil of Almonds, not officinal.
This Essential Oil of Bitter Almonds, or "Oil of Bitter Almonds," although not officinal, must be carefully distinguished from the officinal fixed oil, Oleum Amygdalae, inasmuch as in the crude form generally sold it is highly poisonous, from admixture with 4 to 8 per cent. of hydrocyanic acid. Bitter almonds contain neither the volatile oil nor hydrocyanic acid until moistened, but 2 to 3 per cent. of a body called amygdalin, C20H17NO11, a crystalline glucoside, which, in the presence of water, and under the fermentive influence of the emulsin, breaks up into the volatile oil, hydrocyanic acid, and glucose: C20H17NO11 + 2H1O = C7H6O + HCN + 2C6H12O6. When purified by separation of the hydrocyanic acid, volatile oil of bitter almonds is not poisonous, consisting, as it does, of hydride of benzol (C7H5OH), with benzoic acid (C7H6O2) as a product of oxydation by exposure, and other allied substances, and is used for flavouring sweets. Nitro-benzine, however, which is sometimes substituted for it, having a very similar flavour, is decidedly poisonous.
Preparations of the Sweet Almond.
Oleum Amygdalae. Almond Oil. The oil expressed from bitter and sweet almonds. Pale yellow, nearly inodorous or with a nutty odour, and a bland oleaginous taste. Dose, 2 to 4 fl.dr.
Almond Oil is contained in Unguentum Cetacei, Unguentum Simplex (and its preparations), Unguentum Hydrar-gyri Oxidi Rubri, Unguentum Plumbi Subacetatia Compositum. It is used in preference to olive oil, as it makes a whiter ointment.
Pulvis Amygdalae Compositus. 8 to 4 of Sugar, and 1 of Gum Acacia. Dose, 60 to 120 gr.
Pulvis Amygdala is used in preparing: a. Mistura Amygdalae. - 1, with water, 8. Dose, 1 to 2 fl.oz.
The Sweet Almond is demulcent and nutritive, and has been ground into a flour for making cakes to be eaten by diabetic patients, instead of starchy food. The Compound Powder and Mixture are used only as vehicles for insoluble powders and demulcent cough medicines.
Almond oil has the same action, and is used for the same purposes, as olive oil, which, though less agreeable, is more generally employed as being cheaper. See Oleum Olivae, p. 284.