Page:The American Cyclopædia (1879) Volume VIII.djvu/645

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HEMLOCK SPRUCE with very short petioles, spread horizontally in two directions, and appear as if in two rows. They are flat, dark green above, and glaucous beneath. The cones are about three fourths of an inch long, of a few scales, green- ish when young, but turning brown with age, and placed at the ends of the pendent branches of the preceding year. The wood of the tree is coarse, splits irregularly, and when exposed to the weather decays rapidly; yet with all these disadvantages it affords a large share of the lumber of commerce, and as the white pine disappears hemlock lumber comes more and more into use. It is stronger than white pine, and gives a better hold to nails, and for all work not exposed it is preferred to pine ; for beams, rafters, roof sheathing, and all parts of a house to be covered over, hemlock lumber is largely consumed, as it is for a great deal of other rough work. The great economical value of the hemlock is in its bark, which is largely used for tanning leather, either alone or in con- junction with oak bark; large forests have been destroyed by stripping the bark from the trunks, which were left to decay. As an or- namental tree the hemlock is not excelled in beauty by any native or exotic conifer. As single specimens, in a screen, or in a hedge, it is unequalled. For an ornamental hedge it has the advantage over deciduous plants, as it retains its beauty at all seasons ; and the man- ner in which it bears cutting is a sufficient refutation of the common but erroneous belief that plants which naturally grow to large trees are unfit for hedges. The hemlock may be raised from seeds, but nurserymen get their supplies from the forest; young seedlings a foot high are taken up and planted closely to- gether under a temporary screen of brush to shade them; those which survive the first summer are then planted in nursery rows, and afterward may be removed with safety. Hem- lock gum, incorrectly so called, is a resinous exudation of the hemlock spruce. The tree while growing contains but little resinous juice ; but when it begins to decay, resinous exudations in the form of nodules, from the size of a walnut to nearly that of a hen's egg, are found upon the surface. The bark and chips to which these nodules adhere are boiled in water and the melted resin dipped off. It has a limited use in the preparation of stimulating plasters. In some localities this resin is largely used by the young for chewing, and was former- ly sold for this purpose ; but at present the most approved "chewing gum" is made from pa- raffin e. The young shoots and leaves afford a volatile oil by distillation, which has a local reputation as a rubefacient. It has been used to produce abortion, with fatal results to the mother. The Indian hemlock spruce (A. Bru- noniana), from Xepaul, A. tsuga, from Japan, J A. Ifertentiana, A. Hoolceriana, and A. ATJber- tiana, from the X. W. coast, are species of hemlock spruce to be found in collections of rare evergreens. HEMP C31 HEJIP, the common name of the plant eanna- bis satita, of the order canndbinece, which is by some botanists included in the nettle family (urtwaceae) as a suborder. The same name is applied to the fibre of the inner bark, which is largely used in the manufacture of cordage. It is also used for the fibres of plants of widely different genera ; for the most important of these, see MAXILA, JUTE, and RAMIE. The true hemp is an annual plant, probably a native of India, which has been in cultivation from very early tunes ; it grows from 4 to 12 ft. high, with a branching, angular, rough stem ; the lower leaves are opposite, the upper alternate, and all digitately divided, with five or more coarse- ly toothed leaflets ; the flowers are dioecious, and without petals; the staminate flowers in drooping panicles, each with five sepals and stamens, the pistillate clustered in erect spikes, each consisting of an ovary with two styles em- braced by a calyx of one sepal. Hemp is a plant influenced in a remarkable degree by Stamina** and Ptstflbte Flowers of Hemp. climate, soil, and other conditions; in India it produces a resinous exudation of a marked character (to be presently mentioned), which is entirely wanting in the plant grown in north- ern climates, and there is a great difference in the hemp produced upon the plains and the mountainous regions in the same latitude; when the plant is so grown that seeds may be developed, the fibre is nearly worthless. In many countries hemp is an important agricul- tural product. The principal hemp-producing countries are Russia, Italy, Holland, Turkey, Great Britain, the East Indies, and the United States. St. Petersburg exports this product largely, receiving it from various parts of Rus- sia. Special attention is given to its storage and shipment, and great care is taken to pre- vent the bundles from becoming damp, in which ' condition the hemp would be liable to ferment as in the rotting process. The best Russian hemp is said to be that of Riga, which is brought