The leaves, bark of twigs, and kernels of the Amygdalus Persica, Linné. (Persica vulgaris, De Candolle).
COMMON NAME: Peach tree.
Botanical Source.—The common peach tree is a well-known medium-sized tree, with spreading branches and a brown, smooth bark. Its leaves are from 3 to 5 inches long and about one-third as wide, bright-green, smooth, lanceolate, and serrate, with all the serratures acute. They are borne on short petioles with 1 or 2 glands. The flowers are axillary, solitary, subsessile, and of a beautiful rose-color, and have the odor of hydrocyanic acid. The petals are 5 in number, and the stamens 25. The fruit is a sub-globular, fleshy, tomentose, yellowish-drupe, tinged with purple, and contains an ovate, compressed, acute, stony putamen which is rugosely grooved and perforated on the surface. The seed enclosed by the putamen resembles the almond in odor, taste, and appearance (W).
Description.—The leaves are lanceolate, finely serrate, from 3 to 5 inches long, smooth on both sides, short petiolate, and green in color. They have a bitter taste and faint odor of hydrocyanic acid. The seeds, though smaller, resemble almonds, chemically and physically.
History and Chemical Composition.—The peach tree is commonly considered to be a native of Persia. It is cultivated in all parts of the United States, where its fruit reaches a greater degree of completion and excellence than in any other country. Its height is from 8 to 15 feet, its fruit is large, being from 1 to 3 inches in diameter, juicy, containing sugar, malic acid, etc., and of a delicious flavor. There are about 200 varieties of this fruit, of which probably one-third are clingstones, the flesh adhering to the stone, and the remainder freestones, or clearstones, the flesh free or separating from the stone. The kernels somewhat resemble bitter almonds, but are smaller, and, probably, possess similar medicinal virtues. They contain amygdalin. Hydrocyanic acid can be obtained from most all parts of the tree. Gmelin procured by distillation of the leaves a yellow volatile oil which was heavier than water, and contained hydrocyanic acid. The fixed oil of the seeds is used to adulterate oil of almond, which it resembles. It is known as "peach oil." A liquor known as peach brandy is distilled from the fermented fruit.
Action, Medical Uses, and Dosage.—Peach leaves in infusion have been recommended in morbid irritability of the bladder and urethra, pertussis, ischuria, hematuria, and nausea, as well as in all inflammations of the stomach and abdomen. They act as a sedative in doses of a tablespoonful every hour or two, of the cold infusion; in larger doses they slightly act upon the bowels, and are said to have been useful in removing worms. Amygdalus is the remedy for irritation and congestion of the gastric surfaces. It is a very valuable agent in gastritis to control the vomiting and allay the extreme irritability of the stomach. Cough depending upon irritation of the throat and bronchial mucous membranes, is amenable to it. Prof. J. M. Scudder has found the infusion useful in gastro-intestinal irritation, in cholera infantum with nausea or vomiting, in chronic diarrhoea and dysentery, in chronic hepatitis, in chronic bronchitis, and in dyspepsia attended with gastralgia and nausea. The cold infusion may be freely administered. The kernels are similarly employed in the form of tincture, infusion, or syrup; 4 ounces of the kernels in a quart of brandy is asserted to form a powerful tonic in intermittent fever, and to be remarkably efficacious in curing leucorrhoea; dose, a teaspoonful 3 or 4 times a day. Both leaves and kernels give hydrocyanic acid, with emulsin. Poisoning like that from hydrocyanic acid has occurred from the ingestion of peach seed. Infusion (℥ss of bark of twigs and leaves to water Oj), 1 fluid drachm to 1 fluid ounce. Specific amygdalus, 1 to 10 drops.
Specific Indications and Uses.—Gastric and abdominal tenderness, irritation, or congestion, with elongated, pointed tongue with reddened tips and edges, and prominent papillae, nausea and vomiting; intestinal and bronchial irritation, irritative cough; irritative diarrhoea.
Related Species.—Eriobotrya japonica. Loquat. The leaves and seeds of this tree contain emulsin and amygdalin in amounts sufficient to produce toxic quantities of hydrocyanic acid (P. J. Trans., 1885).
Heteromeles arbutifolia. Toyon. California. Contains hydrocyanic, tannic, and gallic acids. (D. D. Lustig, A. J. P., 1882).