HEMLOCK

A common umbelliferous plant of a peculiar odour, and po e ed of narcotic powers. For medical use the leaves should be collected just before the plant (lowers; if intended for powder, they should be carefuily dried at a temperature not exceeding SIS0; if for extract, lbs juice should be squeezed out by moderate pre ure, and evaporated in a water or steam bath to a proper consistency. The cxtrnet of hrmloek is perhaps the best preparation; but as its activity is liable to van-, it should be given with caution. An average dose is five grains; an over dose produces giddine , wandering of the mind, dilated pupil, convulsive motions of the muscles of the face, and the other symptoms Of this cla of poisons. Hemlock is a powerful sedative, and Often serviceable as a substitute for or an accompaniment to opium. In allaying morbid Irritability of the system attended by any local or general exce of vascular action, as in certain stages of phthysis, in the couehs that are apt to hansr about patients who have suffered from pulmonic in flam at i on,in glandular tumours and unhealthy sores, hemlock Is often preferable to opium. It has also been found very useful in chronic rheumatism, and occasionally in the treatment of whooping cough. A poultice composed of a mixture of finely-powdered fresh hemlock with bread and water, or of the extract of hemlock, is applied to allay the pain of irritable ulcers and cancerous sores: it is sometimes Singularly effectual, at others it seems inert, and sometimes nppears to increase irritation. The virtues of hemlock reside in a peculiar alkaline principle, which has been termed ennin, combined in the herb with a distinct acid, the coneic acid. [s. 567]