Encyclopaedia Britannica
Eleventh Edition
1910-11
HEMP (in O. Eng. _henep_, cf. Dutch _hennep_, Ger. _Hanf_,
cognate with Gr. k\'annabis [in Greek letters], Lat. cannabis),
an annual herb (_Cannabis sativa_) having angular rough stems and
alternate deeply lobed leaves. The bast fibres of _Cannabis_ are
the hemp of commerce, but, unfortunately, the products from many
totally different plants are often included under the general
name of hemp. In some cases the fibre is obtained from the stem,
while in others it comes from the leaf. Sunn hemp, Manila hemp,
Sisal hemp, and Phormium (New Zealand flax, which is neither flax
nor hemp) are treated separately. All these, however, are often
classed under the above general name, and so are the
following:---Deccan or Ambari hemp, _Hibiscus cannabinus_, an
Indian and East Indian malvaceous plant, the fibre from which is
often known as brown hemp or Bombay hemp; Pit\'e hemp, which is
obtained from the American aloe, _Agave americana_; and Moorva or
bowstring-hemp, _Sansevieria zeylanica_, which is obtained from
an aloe-like plant, and is a native of India and Ceylon. Then
there are Canada hemp, _Apocynum cannabinum_, Kentucky hemp,
_Urtica cannabina_, and others.
The hemp plant, like the hop, which is of the same natural order,
Cannabinaceae, is dioecious, i.e. the male and female flowers are
borne on separate plants. The female plant grows to a greater
height than the male, and its foliage is darker and more
luxuriant, but the plant takes from five to six weeks longer to
ripen. When the male plants are ripe they are pulled, put up
into bundles, and steeped in a similar manner to flax, but the
female plants are allowed to remain until the seed is perfectly
ripe. They are then pulled, and after the seed has been removed
are retted in the ordinary way. The seed is also a value
product; the finest is kept for sowing, a large quantity is sold
for the food of cage birds, while the remainder is sent to the
oil mills to be crushed. The extracted oil is used in the
manufacture of soap, while the solid remains, known as oil-cake,
are valuable as a food for cattle. The leaves of hemp have five
to seven leaflets, the form of which is lanceolate-acuminate,
with a serrate margin. The loose panicles of male flowers, and
the short spikes of female flowers, arise from the axils of the
upper leaves. The height of the plant varies greatly with
season, soil and manuring; in some districts it varies from 3 to
8 ft., but in the Piedmont province it is not unusual to see them
from 8 to 16 ft. in height, whilst a variety (_Cannabis setiva_,
variety _gigantea_) has produced specimens over 17 ft. in height.
All cultivated hemp belongs to the same species, _Cannabis
sativa_; the special varieties such as _Cannabis indica_,
_Cannabis chinensis_, &c., owe their differences to climate and
soil, and they lose many of their peculiarities when cultivated
in temperate regions. Rumphius (in the 17th century) had noticed
these differences between Indian and European hemp.
Wild hemp still grows on the banks of the lower Ural, and the
Volga, near the Caspian Sea. It extends to Persia, the Altai
range and northern and western China. The authors of the
_Pharmacographia_ say:---"It is found in Kashmir and in the
Him\'alaya, growing 10 to 12 ft. high, and thriving vigorously at
an elevation of 6000 to 10,000 ft.'' Wild hemp is, however, of
very little use as a fibre producer, although a drug is obtained
from it.
It would appear that the native country of the hemp plant is in
some part of temperate Asia, probably near the Caspian Sea. It
spread westward throughout Europe, and southward through the
Indian peninsula.
The names given to the plant and to its products in different
countries are of interest in connexion with the utilization of
the fibre and resin. In Sans. it is called _goni_, _sana_,
_shanapu_, _banga_ and _ganjika_; in Bengali, _ganga_; Pers.
_bang_ and _canna_; Arab. _kinnub_ or _cannub_; Gr. _kannabis_;
Lat. _cannabis_; Ital. _canappa_; Fr. _chanvre_; Span.
_c\'a\~namo_; Portuguese, _c\'anamo_; Russ. _kon\'opel_; Lettish
and Lithuanian, _kannapes_; Slav. _konopi_; Erse, _canaib_ and
_canab_, A. Sax. _hoenep_; Dutch, _hennep_; Ger. _Hanf_; Eng.
_hemp_; Danish and Norwegian, _hamp_; Icelandic, _hampr_; and in
Swed. _hampa_. The English word _canvas_ sufficiently reveals
its derivation from _cannabis_.
Very little hemp is now grown in the British Isles, although this
variety was considered to be of very good quality, and to possess
great strength. The chief continental hemp-producing countries
are Italy, Russia and France; it is also grown in several parts
of Canada and the United States and India. The Central
Provinces, Bengal and Bombay are the chief centres of hemp
cultivation in India, where the plant is of most use for
narcotics. The satisfactory growth of hemp demands a light rich
and fertile soil, but, unlike most substances, it may be reared
for a few years in succession. The time of sowing, the quantity
of seed per acre (about three bushels) and the method of
gathering and retting are very similar to those of flax; but, as
a 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 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 industry, and it was at one
time very extensively used in the production of yarns for the
manufacture of sail cloth, sheeting, covers, bagging, sacking,
&c. Much of the finer quality is still made into cloth, but
almost all the coarser quality finds its way into ropes and
similar material.
A large quantity of hemp cloth is still made for the British
navy. The cloth, when finished, is cut up into lengths, made
into bags and tarred. They are then used as 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 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 developed in hot countries upon
its leaves and flowering heads; (3) its oily seeds.
Hemp has been employed for its fibre from ancient times.
Herodotus (iv. 74) mentions the wild and cultivated hemp of
Scythia, and describes the hempen garments made by the Thracians
as equal to linen in fineness. Hesychius says the Thracian women
made sheets of hemp. Moschion (about 200 B.C.) records the use
of hempen ropes for rigging the ship "Syracusia'' built for
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-Saxons were well acquainted with the mode of
preparing hemp. Hempen cloth became common in central and
southern Europe in the 13th century.
_Hemp-resin._---Hemp as a drug or intoxicant [sic---the word
"intoxicant" implies "something which poisons", while it is well
known that hemp is not poisonous in any way] for smoking and
chewing occurs in the three forms of 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-green colour, and has a faint
peculiar odour and but a slight taste. It is smoked with or
without tobacco; or it is made into a sweetmeat with honey, sugar
and aromatic spices; or it is powdered and infused in cold water,
yielding a turbid drink, _subdschi_. _Hashish_ is one of the
Arabic names given to the Syrian and Turkish preparations of the
resinous hemp leaves. One of the commonest of these preparations
is made by heating the bhang with water and butter, the butter
becoming thus charged with the resinous and active substances of
the plant.
2. _Ganja_, the guaza [???] of the 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 10 to 15 in. 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 hand like opium; sometimes the resinous
exudation of the plant is made to stick first of all to cloths,
or to the leather garments of men, or even to their skin, and is
then removed by scraping, and afterwards consolidated by
kneading, pressing and rolling. It contains about one-third or
one-fourth its weight of the resin. But the churrus prepared by
different methods and in different countries differs greatly in
appearance and purity. Sometimes it takes the form of 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 linseed oil-cake.
The medicinal and intoxicating [sic] properties of hemp have
probably been known in Oriental countries from a very early
period. An ancient Chinese herbal, part of which was written
about the 5th century B.C., while the remainder is of still
earlier date, notices the seed and 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 Arabia in
the early middle ages. The use of hemp (bhang) in India was
noticed by Garcia d'Orat in 1563. Berlu in his _Treasury of
Drugs_ (1690) describes it as of "an infatuating quality and
pernicious use.'' Attention was recalled to this drug, in
consequence of Napoleon's Egyptian expedition, by de Sacy (1809)
and Rouger (1810). Its modern medicinal use is chiefly due to
trials by Dr O'Shaughnessy in Calcutta (1838--1842). The plant
is grown partly and often mainly for the sake of its resin in
Persia, northern India and Arabia, in many parts of Africa and in
Brazil.
_Pharmacology and Therapeutics._---The 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 [since then the
active substance has been discovered to be delta-9
tetrahydrocannabinol, although marijuana's effects may be further
helped by these other substances]. 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 extract (dose 1/4--1 gr.) or tincture (dose 5--15
minims).
The drug has no external action. The effects of its absorption,
whether it be swallowed or smoked, vary within wide limits in
different individuals and races [sic---in hindsight, the latter
seems Eurocentric and surely false]. 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 is an intoxicant [sic],
resembling alcohol in many features of its action, but differing
in others [how it resembles alcohol in "many features" I have yet
to discover :-)]. The early symptoms are highly pleasurable, and
it is for these, as in the case of other stimulants, that the
drug is so largely consumed in the East. There is a subjective
sensation of mental brilliance, but, as in other cases, this is
not borne out by the objective results. It has been suggested
that the incoordination of nervous action under the influence of
Indian hemp may be due to independent and non-concerted action of
the part of the two halves of the cerebrum. Following on a
decided lowering of the pain and touch senses, there comes a
sleep which is often accompanied by pleasant dreams. There
appears to be no evidence in the case of either the lower animals
or the human subject that the drug is an aphrodisiac. Excessive
indulgence in cannabis indica is very rare, but may lead to
general ill-health and occasionally to insanity [any recorded
cases of this actually happening?]. The apparent impossibility
of obtaining pure and trustworthy samples of the drug has led to
its entire abandonment in therapeutics. When a good sample is
obtained it is a safe and efficient hypnotic, at any rate in the
case of a European [sic---again, this is highly conjectural and
surely false]. The tincture should not be prescribed unless
precautions are taken to avoid the precipitation of the resin
which follows its dilution with water.
See Watt, _Dictionary of the Economic Products of India_.
