Amygdala communis. Almond Tree.
Nat. Ord. — Drupaceae, (De Candolle) Rosaceae. Suborder, Amygdaleae. Sex. Syst. — Icosandria Monogynia.
Amygdala Amara. Bitter Almonds.
Amygdala Dulcis. Sweet Almonds.
Description. — The Amygdalus Communis or Almond tree is a tree from fifteen to twenty feet high, with a pale-brown rugged bark, and dividing into numerous spreading branches. The leaves are upon short footstalks, are about three inches long, and three quarters of an inch broad, lanceolate, acuminate, thin, veined, minutely serrated, with the lower serratures and petioles glandular, and of a bright light-green color. The flowers are large, pink or white, sessile, in pairs, and appearing before the leaves. Calyx reddish, with blunt segments. Petals variable in size, always much larger than the calyx, ovate, concave, irregularly notched. Stamens spreading, about half the length of the petals. Ovary woolly ; style simple. Fruit a leathery, hoary drupe, with the sarcocarp spontaneously cracking and dropping off the putamen. Stone oblong, or ovate, acute, hard in various degrees, always rugged, and pitted with irregular holes. Seed oblong, compressed, ovate, with a brown testa, at the apex of which there is a broad round brown chalaza. Cotyledons very large, plano-convex. Both the sweet and bitter almonds are taken from this tree, of which there are several varieties, — the sweet almond is obtained from the A. Dulcis, and the bitter almond from the A. Amara.
History. — The Almond tree is a native of most of the warm parts of Asia, and Barbary, and is cultivated in many parts of southern Europe. The best of the sweet kind come from Malaga. The kernel of the sweet almond is inodorous, farinaceous, and of an agreeable taste ; that of the bitter almond is also inodorous when entire ; but when triturated with water, has the odor of prussic acid, and the taste resembles that of the peach kernel. Both varieties of kernel contain oil ; the sweet, a fixed oil ; the bitter a fixed oil, and an essential oil impregnated with hydrocyanic acid. The fixed oil may be obtained by expression; it is colorless or slightly yellowish, sweet and bland to the taste. The essential oil may be obtained from the bitter almonds by distillation with water, after having deprived them of their fixed oil. This oil, called Oil of Bitter Almonds, is of a yellowish color, heavier than water, with an acrid, bitter, burning, taste, and the odor of hydrocyanic acid ; it is soluble in alcohol or ether, slightly soluble in water, and deposits on standing, crystals of benzoic acid. This oil does not pre-exist in the almond, but is formed by the action of water on some of its constituents, termed emulsin, and amygdalin ; the latter is a crystalline substance peculiar only to the bitter almond. Oil of bitter almonds is a most active poison, acting as rapidly as hydrocyanic acid, and giving rise to the same symptoms. It is seldom used as a medicine, but is largely employed by perfumers, confectioners, and cooks, who prepare from it an "essence of almonds," which is a solution of two drachms of the oil in six drachms of alcohol.
A potassa soft soap, made with lard and perfumed with essential oil of almonds is sold as a shaving soap, under the name of Saponaceous Cream of Almonds. It is made by melting fine clarified lard, seven pounds, in a porcelain vessel, by means of a salt-water bath, or a steam heat under fifteen pounds pressure; then run into it, very slowly, potassa ley, containing about twenty-six per cent, of caustic potassa, three pounds and twelve ounces, agitating continually from right to left during the whole time. When about half the ley is run in, the mixture begins to curdle ; it will, however, finally become so firm and compact that it cannot be stirred, if the operation is successful. The soap is now finished, but is not pearly ; it will, however, assume that appearance by long trituration in a mortar, gradually adding rectified spirit two ounces, in which has been dissolved, essential oil of almonds two drachms.
Properties and Uses. — Sweet almonds are demulcent, and are chiefly used in emulsion, and as a vehicle for other medicines. The oil or emulsion has been employed in cough, diseases attended with intestinal irritation, and for mitigating the acrimony of the urine in calculous affections, cystitis, gonorrhea, etc. Externally, the oil is sometimes used in lotions and cosmetics. Dose of the oil, one to two drachms. Bitter almonds are sedative, and in large doses poisonous. The oil of bitter almonds, or bitter almond water, is commonly employed, and may be used as a substitute for hydrocyanic acid. Dose of the oil, one quarter of a drop to one drop, gradually and cautiously increased. Seldom used.
Off. Prep. — Aqua Amygdalae Amara ; Mistura Copaibae Composita ; Oleum Amygdalae.