This section is from "The American Cyclopaedia", by George Ripley And Charles A. Dana. Also available from Amazon: The New American Cyclopędia. 16 volumes complete..
Datura, a genus of rank, poisonous, narcotic plants, of the order solanacece, having showy flowers, some of which possess fragrance as well as beauty. The word datura is said to be derived from the Arabic tatorah, which indicates the oriental origin of the herb. Two varieties of D. stramonium (known as thorn-apple, and also in some parts of this country as Jamestown weed) grow in the United States, one having a green stem and white flowers, the other a dark red stem and purple flowers. The latter is sometimes considered a distinct species (D. tatula). The leaves and seeds are officinal under the name stramonium. Their activity depends upon a crystallizable alkaloid called daturia, which closely resembles atropia and hyoscyamia chemically and physiologically. Stramonium gives rise to symptoms closely resembling those produced by belladonna and henbane, such as dryness of the throat, active delirium, usually of a whimsical and fantastic character, dilatation of the pupils, and a rapid pulse. Death may occur, with coma and convulsions. Accidental poisoning, especially in children, is not very rare, the plant with its seeds being abundant about dwelling houses and waste places. The leaves and bruised roots, smoked like tobacco, are often efficient in relieving the paroxysms of spasmodic asthma.
This practice was introduced into England from the East Indies, where the D.ferox is used for this purpose. Ten to 30 grains of the leaves are sufficient for once smoking. They should be smoked with caution, and the practice discontinued if it produces vertigo or dryness of the throat. Stramonium is also used for the relief of spasmodic cough, neuralgia, and dysmenorrhoea; and oculists employ it locally to produce dilatation of the pupil. It is given in the form of the powdered leaves of the plant, of extract, and of tincture. The dose of the leaves is from 1 to 3 grs.; of the extract, 1/4 to 1/2 gr.; of the tincture, from 10 to 30 drops. The active principle, daturia, is rarely used in medicine by itself. - D.fastuosa has a polished, purple stalk, large leaves, and beautiful flowers, of a rich purple outside, pure satiny white within, of an agreeable odor, sometimes also having semi-double blossoms. The odor of D. Wrightii is also pleasant; its flowers are large, of a creamy white, delicately tinted with violet as they fade.
D. arborea (now Brugmansia) is one of the greatest ornaments of gardens; its flowers are trumpet-shaped, nearly a foot in length, coming out of the division of the branches, pale yellowish outside and white within, and diffusing a delightful fragrance in the open air. They are all raised from seeds or propagated by cuttings, and even the roots of the herbaceous kinds survive if protected from severe frost.