Hemp (Cannabis sativa), an annual plant, which, like the nop (q.v.), belongs to the Cannabinaoeae, a sub-order of the Urticaoeae, and has been employed as a fibre, and as a source of a medicinal and intoxicating resin from very ancient times. The hemp plant is probably a native of temperate Asia, near the Caspian. It is dioecious, the female plant being the larger, and reaching to 10, or even 17 feet in height. The leaves consist, of from five to seven lanceolate-acuminate leaflets with serrate margins, arranged palmately. The male flowers are in loose panicles, the female ones in short spikes. Hemp is cultivated in Suffolk and Lincolnshire and in Ireland; but chiefly imported from Russia, Germany, Italy, and the United States, to London, Liverpool, Hull, and Leith. In the official returns various other fibres, such as Manilla hemp (q.v.) from the Philippines, Suna hemp (q.v.) from India, and Pita fibre (q.v.) from Mexico, are included under hemp. Hemp is used for all kinds of cordage, sacking, canvas, and sail-cloth. The preparation of the fibre is similar to that of flax (q.v.).
Hemp-seed, which really consists of small nuts or fruits, is used as a food "for cage-birds, and contains 34 per cent. of a drying oil, inferior to linseed oil. The oil-cake is purgative. As a drug or intoxicant hemp is used in enormous quantities in the East under the three forms: bhang, the dried leaves and twigs, gawja or guaza, the flowering and fruiting clusters, and churrus, the exuded resin itself. Hashish is a preparation of ganja or bhang with butter. The chemical characters of the resin are imperfectly known. It acts on the nervous system, producing exhilaration and appetite in small doses, hallucinations and even catalepsy in larger ones.
It has been employed as an antispasmodic and anodyne in tetanus and hydrophobia.