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HEMLOCK (in O. Eng. hemlic or hymlice...

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Originally appearing in Volume V13, Page 263 of the 1911 Encyclopedia Britannica.
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HEMLOCK (in O. Eng. hemlic or hymlice; no cognate is found in any other See also:language, and the origin is unknown)  , the Conium maculatum of botanists, a biennial umbelliferous plant, found See also:wild in many parts of See also:Great See also:Britain and See also:Ireland, where it occurs in See also:waste places on hedge-See also:banks, and by the See also:borders of See also:fields, and also widely spread over See also:Europe and temperate See also:Asia, fnd naturalized in the cultivated districts of See also:North and See also:South See also:America . It is an erect branching plant, growing from 3 to 6 ft. high, and emitting a disagreeable See also:smell, like that of mice . The stems are hollow, smooth, somewhat See also:glaucous See also:green, spotted with dull dark See also:purple, as alluded to in the specific name, maculatum . The See also:root-leaves have See also:long furrowed footstalks, sheathing the See also:stem at the See also:base, and are large, triangular in outline, and repeatedly divided or See also:compound, the ultimat.e and very numerous segments being small, ovate, and deeply incised at the edge . These leaves generally perish after the growth of the flowering stem, which takes See also:place in the second See also:year, while the leaves produced on the stem became gradually smaller upwards . The branches are all terminated by compound many-rayed umbels of small See also:white See also:flowers, the See also:general involucres consisting of several, the partial ones of about three See also:short lanceolate bracts, the latter being usually turned towards the outside of the umbel . The flowers are succeeded by broadly ovate fruits, the mericarps (See also:half-fruits) having five ribs which, when mature, are waved or crenated; and when cut across the albumen is seen to be deeply furrowed on the inner See also:face, so as to exhibit in See also:section a reniform outline . The fruits when triturated with a See also:solution of See also:caustic potash evolve a most unpleasant odour . See also:Hemlock is a virulent See also:poison, but it varies much in potency according to the conditions under which it has grown, and the See also:season or See also:stage of growth at which it is gathered . In the first year the leaves have little See also:power, nor in the second are their properties See also:developed until the flowering See also:period, at which See also:time, or later on when the fruits are fully grown, the plant should be gathered . The wild plant growing in exposed situations is to be preferred to See also:garden-grown samples, and is more potent in dry warm summers than in those which are dull and moist . The poisonous See also:property of hemlock resides- chiefly in the See also:alkaloid canine or conid which is found in both the fruits and the leaves, though in exceedingly small proportions in the latter .

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Conine resembles See also:nicotine in its deleterious See also:action, but is much less powerful . No chemical antidote for it is known . The plant also yields a second less poisonous crystallizable base called conhydrine, which may be converted into conine by the See also:abstraction of the elements of See also:water . When collected for medicinal purposes, for which both leaves and fruits are used, the former should be gathered at the time the plant is in full blossom, while the latter are said to possess the greatest degree of See also:energy just before they ripen . The fruits are the See also:chief source whence conine is prepared . The See also:principal forms in which hemlock is employed are the See also:extract and juice of hemlock, hemlock See also:poultice, and the See also:tincture of hemlock fruits . Large doses produce vertigo, See also:nausea and See also:paralysis; but in smaller quantities, administered by skilful hands, it has a sedative action on the nerves . It has also some reputation as an alterative and resolvent, and as an See also:anodyne . The acrid narcotic properties of the plant render it of some importance that one should be able to identify it, the more so as some of the compound-leaved umbellifers, which have a general similarity of See also:appearance to it, See also:form wholesome See also:food for See also:man and animals . Not only is this knowledge desirable to prevent the poisonous plant being detrimentally used in place of the wholesome one; it is equally important in the opposite See also:case, namely, to prevent the. inert being substituted for the remedial See also:agent . The plant with which hemlock is most likely to be confounded is Anthriscus sylvestris, or cow-See also:parsley, the leaves of which are freely eaten by See also:cattle and rabbits; this plant, like the hemlock, has spotted stems but they are hairy, not hairless; it has much-divided leaves of the same general form, but they are downy and aromatic, not smooth and nauseous when bruised; and the See also:fruit of Anthriscus is linear-oblong and not ovate .

End of Article: HEMLOCK (in O. Eng. hemlic or hymlice; no cognate is found in any other language, and the origin is unknown)
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