This section is from the book "A Treatise On Therapeutics, And Pharmacology Or Materia Medica Vol1", by George B. Wood. Also available from Amazon: Part 1 and Part 2.
The fruit of Anethum graveolens, or common dill-plant, though little employed in this country, is still considerably used in Great Britain, and retains a place in the British Pharmacopoeia. The plant is annual and umbelliferous, belonging to the same family a- the fennel and caraway, and producing a similar fruit. It is a native of the south of Europe, and is cultivated almost everywhere in gardens. The fruits, commonly, though erroneously, called seeds, are about a line in diameter, and distinguished from the other officinal fruits of this kind by a yellowish membranous expansion that surrounds them. They have an aromatic odour and taste, but less agreeable than those of anise, caraway, or fennel, and have consequently not been introduced into our Pharmacopoeia. These properties they owe to a volatile oil, which is separated by distillation. Water and alcohol extract their virtues. The Oil (Oleum Anethi, Br.) and a Distilled Water (Aqua Anethi, Br.), prepared from the fruits, are the forms in which dill is most commonly used. It is given for the general purposes of the aromatics; the fruits in the dose of from a scruple to a drachm, and the oil in that of three or four drops. Dill water is used mainly as a vehicle.