ORANGE, LEMON, LIME—Medical Properties of. These are all species of the genus Citrus. Save the root, wood, and bark, every one of them yields from every part something of use in medicine or per fumery. Citrus aurantium, or sweet orange, is too well known to require description. Its leaves and unripe berries yield by distillation a fragrant oil called essence de petit grain. The small green unripe fruits of this species, and also of the Citrus bigaradia, or bitter orange, have an aromatic odour and bitter taste, and are used to flavour " When smoothed by a lathe, they form the issue peas of the shops." The flowers of the sweet, but still more the bitter, orange are distilled to yield orange-flower water, termed aqua Naphae. This contains free acetic acid ; this acid acts upon the lead in the joining of the stills In which it is prepared, or the leaden vessels in which it is imported ; so that orange-flower water often contains a notable quan tity of acetate or sugar of lead, giving rise to some troublesome decompositions when iodine or several other matters are mixed with it, as first pointed out by Mr. Squire. It is directed to be tested with hydrosulphuric acid, to ascertain its freedom from this contamination. Oil of orange-flowers, called dem Neroli, is obtained by distillation of the flowers of the sweet and still more of the bitter orange. An inferior sort is got by expression of the grated rind.
The Citrus medico, or citron, yields two volatile oils, one termed essence or essential oil of citron, the other essence or essential oil of cedrat. This must not be confounded with cedrat, which is a liqueur or compound of the distilled oil of lemons and simple syrup. Neither must it be confounded with citronelle, or can de Barbades, which is a West Indian distilled spirit of orange, lemon-peel, and aromatics, with proof spirit Creme des Barbades is similar, prepared with rum. Citronella Zeylanica, or oil of lemon-grass, from Ceylon and the Moluccas, is obtained from the A ndropogon citratum, a grass, not of the orange tribe. Citrus bergantia yields from the rind of the fruit, by either expression or distillation, the well-known essence or volatile oil of bergamot. This name is also applied to a volatile oil obtained from a mint, the Mentha eitrata (or M. odorata of Sole, in his work on ' British Mints '), called bergamot mint. The volatile oil of the genuine
bergamot is said by Llebig to differ, by containing oxygen, from the other oils of this genus, which are mere carburets of hydrogen. This similarity of chemical composition renders it difficult to distinguish mint oil from that of bergamot ; but in all probability there is a difference in their.polarising power or tendencies.
As stimulants, carminatives, and antispasmodics, these oils arc occa sionally used pure, on sugar, but mostly as constituents of tinctures and mixtures. Many of them enter into the composition of eau de Cologne, where ammonia seems the chief solvent. The pure oil of the lemon, either spirted or carefully dropped into the eye, has been used with benefit in chronic inflammation of that organ, whether of rheu matic or scrofulous origin, particularly where there is a tendency to the formation of specks of the cornea. It acts like the Finum, opii.
The fresh rind of the sweet orange, rasped, and pounded with three times its weight of loaf sugar till well incorporated, constitutes the confectio aurantii of the Pharmacopoeia. The rind of the sweet, more frequently of the bitter, orange, occasionally of the citron, and even the lemon, is made into a conserve by having the pulp scooped out, then boiled, and boiled sugar poured over the rind.
The rind or peel of the sweet, but more frequently of the bitter, orange, and also the citron, are frequently candied and used at dessert, or the last In rich puddings, buns (Scotch), and short-bread. The rind or peel of the bitter orange, from which the soft, white, downy inside lining has been carefully stripped off, constitutes what is termed Flared° aurantii, a wholesome stomachic. The bitter orange, termed Seville, is made in Scotland into a conserve called marmalade. The whole of the fruit, except the pips and inside lining (termed doff) of the peel, is used for this purpose, being boiled till the fruit is made quite tender ; the skin is then to be cut into fine shreds (the finer the better, or rasped), and the whole boiled till it jellies. The flavour is greatly improved by using a few of the more fragrant-skinned sweet oranges along with the bitter. When properly prepared, this forms one of the most wholesome conserves at breakfast or dessert.