AROMATICS constitute ii, class of medicines which owe their properties to the essen tial oils, to benzoic and cinnamic acids, to volatile products of distillation, or to odorous glandular secretions. The plants that contribute to this class of medicines are those which yield essences, camphor, or odorous resins, and amongst the families which yield the most important aromatics are the labiatx, umbelliferm, lauracefe, myrtacew, atiran tiacew, conifers?, scitaminete, orchidefe, etc. In some cases, the aromatic matter is diffused throughout all parts of the plant, but it is usually condensed in particular i organs, such as the root, in the case of ginger and galanga; or the bark, in the case of cinnamon, canella, and c,ascarella; or the flowers, as in the case of cloves; or the fruit, as in the case of anise and vanilla; or the wood, as in the case of sandal-wood and aloes wood; or the leaves, as in the case of most of the labiatte, umbelliferte, etc.
A. may be arranged in the following sub-classes: (1) Those in which the active prin ciple is an essential oil, as the oil of thyme, lavender, eajeput, neroli, fennel, etc. (2) Those containing camphor, or an allied body, such as artificial camphor obtained from turpentine. (3) Bitter aromatics, in which there is a mixture of a bitter principle and an essential oil, as chamomile, tansy, wormwood, etc. These are tonics and vermi
fuges. (4) Those of which musk is the type, such as civet and amber; and certain plants with a musk-like odor, such as make moscata, mimulus moschatus, and hibiscus abelmos thus. (5) Those containing a fragrant resin, as benzoin, myrrh, olibanum, storax, and the balsams of Peru and loin, which possess stimulant properties. (6) Lastly, those which are artificially produced by destructive distillation, as tar, creosote, benzol, or the various empyreumatic oils.
As a general rule, these substances act as diffusible stimulants of more or less power, and as antispasmodics, while those in which a bitter principle is present act as verini fuges and tonics. The whole class were formerly regarded as possessing disinfectant and antiseptic properties, and there is no doubt that some, as coal-tar, creosote, etc., strongly possess this property. In this country we usually associate aromatics with other medicines; but in France aromatic infusion, lotions, baths, etc., are much pre scribed. It will suffice to give the composition of aromatic infusion as an illustration. Take equal parts of the leaves of sage, ordinary and lemon thyme, hyssop, origauum, wormwood, and mint. Infuse 50 parts of these leaves in 100 parts of boiling water.