Hemlock (Conium maculatum) is a poisonous biennialherb of the family Umbelliferae supposed to be identical with the plant koneion of the Greeks.. It is a tall, erect, branching biennial, with a smooth, shining, hollow stem usually marked with purple spots. It has elegant, much divided leaves which when bruised emit a nauseous odour. The flowers are white in compound umbels of ten or more rays surrounded by a general involucre of three to seven leaflets.
Hemlock is found in Britain and throughout Europe and temperate Asia in waste places, banks, and under walls. It is said to be fatal to cows when they eat it, but that horses, goats, and sheep may feed upon it without danger. In the human subject it causes paralysis, convulsions, and death. The poison administered to Socrates is supposed to have been a decoction of it, though others are of opinion that the potion was obtained from water-hemlock (Cicuta virosa).
Hemlock is a powerful sedative, and is used medicinally. The extract is considered the best preparation. It was formerly used as a substitute for, or as an accompaniment to opium. It has been found very useful in chronic rheumatism and in hooping-cough, in allaying the pain of irritable sores and cancerous ulcers. The virtues of hemlock reside in an alkaline principle termed coma or coniine. Research Hemlock