This section is from the book "An Experimental History Of The Materia Medica", by William Lewis.
Caruon Pharm. Lond. Carii Pharm. Edinb. Cuminum pratense carui officinarum C. B. Carum Carvi Linn. Caraway: an umbelliferous plant, with striated branched stalks, two or three feet high; and finely divided leaves set in pairs along a channelled rib; every two of which ribs or pedicles cross one another at their origin on the stalk: the seeds are small, of a brownish or blackish colour, somewhat bent, striated, flat on one side, convex on the other. It is a native of the northern climates: in this kingdom it is rarely found wild, but commonly cultivated in gardens for culinary and confectionary as well as medicinal purposes. It is biennial.
Caraway seeds are an useful stomachic and carminative; of a sufficiently agreeable aromatic smell, and a moderately warm taste: they are given, in substance, from a scruple to a dram. The leaves have the same kind of flavour with the seeds, but are considerably weaker and less grateful. The roots have a sweetish taste, accompanied with a slight warmth, and very little smell.
The seeds give out the whole of their virtue, by moderate digestion, to rectified spirit; for after the action of this menstruum they prove insipid and inodorous: the tincture tastes strongly of the caraways, but their smell is in great mea-sure covered by the menstruum. The spirit, gently distilled off from the filtered liquor, brings over very little of the flavour of the caraways, leaving nearly all their active matter concentrated in the extract, which proves a very warm pungent aromatic. The colour, both of the tincture and extract, is a yellowish verging to green.
Infusions of the seeds in water are stronger in smell than the spirituous tincture, but much weaker in taste: after repeated infusion in fresh portions of water, they still give a considerable taste to spirit. The colour of the watery infusions is a pale reddish brown. In distillation or evaporation, water elevates all the aromatic part of the caraways: the remaining extract is almost insipid, and thus discovers, that in caraways there is less, than in most of the other warm seeds of European growth, of a bitterish or ungrateful matter joined to the aromatic. Along with the aqueous fluid there arises in distillation a very considerable quantity, about one ounce from thirty, of essential oil, of a bright yellow colour, smelling strongly of the caraway, in taste hotter and more pungent than those obtained from most of our other warm seeds*(a): this oil is given from one to five or six drops, as a carminative; and is supposed also to be of peculiar efficacy for promoting urine, to which it communicates some degree of its smell. The leaves of the plant afford likewise an oil, nearly similar, both in colour and quality, to that of the seeds, but in far less quantity: sixteen pounds of the herb in flower, stripped from the stalks, yielded scarcely an ounce. The essential oil of the seeds is directed as an officinal; as also a cordial water, pretty strongly flavoured with them by drawing off a gallon †or nine pints ‡of proof spirit from half a pound of the caraways.