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See also:HEMP (in O. Eng. henep, cf. Dutch hennep, Ger. Hanf , cognate with Gr. Kavval3er, See also:Lat. cannabis)
, an See also:annual See also:herb (Cannabis saliva) having angular rough stems and alternate deeply lobed leaves
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The bast See also:fibres of Cannabis are the See also:hemp of See also:commerce, but, unfortunately, the products from many totally different See also:plants are often included under the See also:general name of hemp
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In some cases the fibre is obtained from the See also:stem, while in others it comes from the See also:leaf
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See also:Sunn hemp, See also:Manila hemp, Sisal hemp, and See also:Phormium (New See also:Zealand See also:flax, which is neither flax nor hemp) are treated separately
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All these, however, are often classed under the above general name, and so are the following:—See also:Deccan or Ambari hemp, Hibiscus cannabinus, an See also:Indian and See also:East Indian malvaceous plant, the fibre from which is often known as See also: The leaves of hemp have five to seven leaflets, the See also:form of which is lanceolate-See also:acuminate, with a serrate margin . The loose panicles of male flowers, and the See also:short spikes of female flowers, arise from the axils of theupper leaves . The height of the plant varies greatly with See also:season, See also:soil and manuring; in some districts it varies from 3 to 8 ft., but in the See also:Piedmont See also:province it is not unusual to see them from 8 to 16 ft. in height, whilst a variety (Cannabis sctiva, variety gigantea) has produced specimens over 17 ft. in height . All cultivated hemp belongs to the same See also:species, Cannabis saliva; the See also:special varieties such as Cannabis indica, Cannabis chinensis, &c., owe their See also:differences to See also:climate and soil, and they lose many of their peculiarities when cultivated in temperate regions . Rumphius (in the 17th See also:century) had noticed these differences between Indian and See also:European hemp . See also:Wild hemp still grows on the See also:banks of the See also:lower Ural, and the See also:Volga, near the See also:Caspian See also:Sea . It extends to See also:Persia, the See also:Altai range and See also:northern and western See also:China . The authors of the Pharmacographia say:—" It is found in See also:Kashmir and in the See also:Himalaya, growing 10 to 12 ft. high, and thriving vigorously at an See also:elevation of 6000 to 1o,000 ft." Wild hemp is, however; of very little use as a fibre producer, although a See also:drug is obtained from it . It would appear that the native See also:country of the hemp plant is in some See also:part of temperate See also:Asia, probably near the Caspian-Sea . It spread westward throughout See also:Europe, and southward through the Indian See also:peninsula . The names given to the plant and to its products in different countries are of See also:interest in connexion with the utilization of the fibre and See also:resin . In Sans. it is called goni, sang, shanapu, banga and ganjika; in See also:Bengali, ganga; Pers. See also:bang and canna; Arab. kinnub or cannub; Gr. kannabis; See also:Lat. cannabis; Ital. canappa; Fr. chanvre; Span. cdnamo; Portuguese, cdnamo; Russ. kon6pet; Lettish and Lithuanian, kannapes; Slay. konopi; Erse, canaib and canab; A . See also:Sax. hoenep; Dutch, hennep; Ger . Hanf; Eng. hemp; Danish and See also:Norwegian, hamp; Icelandic, hampr; and in Swed. hantpa . The See also:English word See also:canvas sufficiently reveals its derivation from cannabis . Very little hemp is now grown in the See also:British Isles, although this variety was considered to be of very See also:good quality, and to possess See also:great strength . The See also:chief See also:continental hemp-producing countries are See also:Italy, See also:Russia and See also:France; it is also grown in several parts of Canada and the See also:United States and India . The Central Provinces, See also:Bengal and Bombay are the chief centres of hemp cultivation in India, where the plant is of most use for See also:narcotics .. The satisfactory growth of hemp demands a See also:light, See also:rich and fertile soil, but, unlike most substances, it may be reared for a few years in See also:succession . The See also:time of sowing, the quantity of seed per See also:acre (about three bushels) and the method of gathering and retting are very similar to those of flax; but, as a See also:rule, it is a hardier plant than flax, does not possess the same pliability, is much coarser and more brittle, and does not require the same amount of See also:attention during the first few weeks of its - growth . The very finest hemp, that grown in the province of Piedmont, Italy, is, however, very similar to flax, and in many cases the two fibres are mixed in the same material . The hemp fibre has always been valuable for the rope See also:industry, and it was at one time very extensively used in the See also:production of yarns for the manufacture of See also:sail See also:cloth, sheeting, covers, See also:bagging, sacking, &c . Much of the finer quality is still made into cloth, but almost all the coarser quality finds its way into See also:ropes and similar material . A large quantity of hemp cloth is still made for the British See also:navy . The cloth, when finished, is cut up into lengths, made into bags and tarred . They are then used as See also:coal sacks . There is also a quantity made into sacks which are intended to hold very heavy material . Hemp yarns are also used in certain classes of carpets, for special bags for use in cop See also:dyeing and for similar special purposes, but for the ordinary bagging and sacking the employment of hemp yarns has been almost entirely supplanted by yarns made from the jute fibre . Hemp is grown for three products—(1) the fibre of its stem; (2) the resinous secretion which is See also:developed in hot countries upon its leaves and flowering heads; (3) its oily seeds . Hemp has been employed for its fibre from See also:ancient times . See also:Herodotus (iv . 74) mentions the wild and cultivated hemp of See also:Scythia, and describes the hempen garments made by the Thracians as equal to See also:linen in fineness . See also:Hesychius says the Thracian See also:women made sheets of hemp . Moschion (about 200 B.C.) records the use of hempen ropes for See also:rigging the See also:ship Syracusia " built for See also:Hiero II . The hemp plant has been cultivated in northern India from a considerable antiquity, not only as a drug but for its fibre . The Anglo-See also:Saxons were well acquainted with the mode of preparing hemp . Hempen cloth became See also:common in central and See also:southern Europe in the 13th century . Hemp-resin.—Hemp as a drug or intoxicant for smoking and chewing occurs in the three forms of See also:bhang, ganja and charas . 1 . Bhang, the Hindustani siddhi or sabzi, consists of the dried leaves and small stalks of the hemp; a few fruits occur in it . It is of a dark brownish-See also:green See also:colour, and has a faint See also:peculiar odour and but a slight See also:taste . It is smoked with or without See also:tobacco; or it is made into a sweetmeat with See also:honey, See also:sugar and aromatic spices; or it is powdered and infused in See also:cold See also:water, yielding a turbid drink, subdschi . See also:Hashish is one of the Arabic names given to the Syrian and See also:Turkish preparations of the resinous hemp leaves . One of the commonest of these preparations is made by See also:heating the bhang with water and See also:butter, the butter becoming thus charged with the resinous and active substances of the plant . 2 . Ganja, the guaza of the See also:London brokers, consists of the flowering and fruiting heads of the female plant . It is brownish-green, and otherwise resembles bhang, as in odour and taste . Some of the more esteemed kinds of hashish are prepared from this ganja . Ganja is met with in the Indian bazaars in dense bundles of 24 plants or heads apiece . The hashish in such extensive use in Central Asia is often seen in the bazaars of large cities in the form of cakes, 1 to 3 in. thick, 5 to 10 in. broad and so to 15 in. See also:long . 3 . Charas, or churrus, is the resin itself collected, as it exudes naturally from the plant, in different ways . The best sort is gathered by the See also:hand like See also:opium; sometimes the resinous exudation of the plant is made to stick first of all to cloths, or to the See also:leather garments of men, or even to their skin, and is then removed by scraping, and afterwards consolidated by kneading, pressing and See also:rolling . It contains about one-third or one-See also:fourth its See also:weight of the resin . But the churrus prepared by different methods and in different countries differs greatly in See also:appearance and purity . Sometimes it takes the form of See also:egg-like masses of greyish-brown colour, having when of high quality a shining resinous fracture . Often it occurs in the form of irregular friable lumps, like pieces of impure See also:linseed oil-cake . The medicinal and intoxicating properties of hemp have probably been known in See also:Oriental countries from a very See also:early See also:period . An ancient See also:Chinese herbal, part of which was written about the 5th century B.e., while the remainder is of still earlierdate, notices the seed and See also:flower-bearing kinds of hemp . Other early writers refer to hemp as a remedy . The medicinal and dietetic use of hemp spread through India, Persia and See also:Arabia in the early See also:middle ages . The use of hemp (bhang) in India was noticed by See also:Garcia d'See also:Orta in 1563 . Berlu in his See also:Treasury of Drugs (169o) describes it as of " an infatuating quality and pernicious use." Attention was recalled to this drug, in consequence of See also:Napoleon's See also:Egyptian expedition, by de Sacy (1809) and Rouger (r81o) . Its See also:modern medicinal use is chiefly due to trials by Dr O'Shaughnessy in See also:Calcutta (1838-1842) . The plant is grown partly and often mainly for the See also:sake of its resin in Persia, northern India and Arabia, in many parts of See also:Africa and in See also:Brazil . See also:Pharmacology and See also:Therapeutics.—The See also:composition of this drug is still extremely obscure; partly, perhaps, because it varies so much in individual specimens . It appears to contain at least two alkaloids—cannabinine and tetano-cannabine—of which the former is volatile . The chief active principle may possibly be neither of these, but the substance cannabinon . There are also resins, a volatile oil and several other constituents . Cannabis indica—as the drug is termed in the pharmacopoeias—may be given as an See also:extract (dose 4-1 gr.) or See also:tincture (dose 5-15 minims) . The drug has no See also:external See also:action . The effects of its absorption, whether it be swallowed or smoked, vary within wide limits in different individuals and races . So great is this variation as to be inexplicable except on the view that the nature and proportions of the active principles vary greatly in different specimens . But typically the. drug in an intoxicant, resembling See also:alcohol in many features of its action, but differing in others . The early symptoms are highly pleasurable, and it is for these, as in the See also:case of other stimulants, that the drug is so largely consumed in the East . There is a subjective sensation of See also:mental brilliance, but, as in other cases, this is not borne out by the See also:objective results . It has been suggested that the incoordination of See also:nervous action under the See also:influence of Indian hemp may be due to See also:independent. and non-concerted action on the part of the two halves of the cerebrum . Following on a decided lowering of the See also:pain and See also:touch senses, which may even See also:lead to See also:complete loss of cutaneous sensation, there comes a See also:sleep which is often accompanied by pleasant dreams . There appears to be no See also:evidence in the case of either the lower animals or the human subject that the drug is an aphrodisiac . Excessive See also:indulgence in cannabis indica is very rare, but may lead to general See also:ill-See also:health and occasionally to See also:insanity . The apparent impossibility of obtaining pure and trustworthy samples of the drug has led to its entire See also:abandonment in therapeutics . When a good See also:sample is obtained it is a safe and efficient hypnotic, at any See also:rate in the case of a European . The tincture should not be prescribed unless precautions are taken to avoid the precipitation of the resin which follows its dilution with water . See See also:Watt, See also:Dictionary of the Economic Products of India .
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