Citrus aurantium. Orange.
Nat. Ord.— Aurantiaceae. Sex. Syst. — Polyadelphia Icosandria.
The Peel or Outer Rind
Description. — Citrus Aurantium is a middle-sized evergreen tree, much branched, and covered with a smooth, shining, greenish-brown bark. Branches generally with axillary spines. Leaves alternate, entire, ovate-oblong, acute, a little serrulated, of a shining-green color, and with footstalks more or less winged. The flowers are large, white, and very fragrant, and arise from the smaller branches on simple and divided peduncles. The calyx is saucer-shaped, and divided into five pointed sepals. The petals are five, oblong, concave, white, and beset with numerous small glands. The stamens are twenty or more, united at their base into three or more sets, and support vertical, yellow anthers. The ovary is superior, roundish, bearing a cylindrical style, terminating with a globose stigma. The fruit is globose, depressed, of a reddish-yellow color externally, and internally divided into several cells, filled with a mucilaginous pulp ; each cell containing from two to four white seeds, with a cartilaginous skin. The rind of the fruit is double, consisting of an external thin and glandular layer, tilled with a fragrant essential oil, and of an internal one, thick, white, spongy, insipid, and inodorous.
History. — The orange is a native of China and India, and is cultivated in the southern parts of Europe and America, and in the West Indies. Its varieties are numerous. The fruit likewise differs in its character, that of the C. Aurantium being sweet, while that of the C. Vulgaris, or C. Bigaradia, the Seville orange, is sour and bitterish. The leaves are studded with vesicles containing an essential oil, and have a bitter aromatic taste, and when rubbed between the fingers are highly fragrant. They yield by distillation an oil termed Essence de Petit Grain.
An infusion of them is sometimes employed as a gently stimulant diaphoretic. The flowers have a delicious fragrance, which is imparted to the surrounding atmosphere, but which is lost by drying ; those of the bitter orange are considered the most delicate. They owe their aroma to an essential oil, which may be obtained by distillation; it is termed Oil of Neroli, and is much used in perfumery. An orange flower water is prepared in Italy and France, which is nearly colorless, has a rich odor of the flowers, and a bitterish, aromatic taste ; it is used exclusively as a perfume, although reputed to possess antispasmodic virtues. The peculiar fragrance of the flowers may be preserved for a long time by beating them into a pulp with one-fourth their weight of common salt. The juice of the orange consists chiefly of sugar, mucilage and citric acid. The outer rind of the mature fruit is the officinal part, the inner being destitute of useful properties, and the two should always be separated from each other when drying the rind for medical purposes, as the spongy, inner rind by its affinity for moisture produces a disposition in the peel to become moldy. Orange peel has a deep orange color, a grateful aroma, and a pleasant bitter taste, that of the Seville orange being much more bitter than that of the other variety. It contains a volatile oil in visible vesicles, and which is lost in drying, a saccharine principle, a bitter principle, and ligneous fiber. The volatile oil may be obtained by expression from the fresh-grated rind, or by distillation with water. Water or alcohol takes up the sensible properties of the rind. The finest Orange oil, which must not be confounded with the Oil of Neroli, is obtained from Portugal, and is prepared from the rind of the sweet orange. It has a pale straw tint, and a rich fragrance of the rind. It is imported in tinned copper cans, and is much used in perfumery and for other purposes. On exposure it spoils rapidly, acquiring a terebinthinate odor. When about the size of a pea or cherry, the fruit is sold under the name of Orangettes or Curacoa Oranges ; and the small ones are sometimes used to maintain the discharge from issues.
Properties and Uses. — Orange peel is a mild bitter tonic, carminative and stomachic. It is seldom used alone, but is employed generally to flavor other medicines, or to correct their nauseating tendency. It thus forms a very useful addition to bitter tinctures, infusions, or decoctions, as of cinchona bark, quassia, columbo, etc. ; though care should be taken not to subject it to long boiling, on account of its oil, which will thus be driven off. As a tonic the rind of the Seville orange is preferred; its dose in substance is from thirty to sixty grains, three times a day. Large quantities of it have caused violent colic, convulsions, and even death. The juice of the orange is not only a light refrigerant article of diet, but has a direct beneficial medicinal influence in several diseases; as in all fevers and exanthematous diseases, where acids are craved, and the patient's tongue is coated brown, black, or any intermediate color; in such cases its free use may be allowed with advantage ; it is also useful as an antiscorbutic in scurvy. In administering the juice, the membranous portion should always be carefully rejected. The distilled water of the flowers are said to have proved beneficial in chorea, hysteria, epilepsy, and many other nervous disorders, in doses of one or two ounces.
Off. Prep. — Aqua Florum Aurantii.