HEROIN. The trade name for a derivative of morphine (diacetylmorphine hydrochloride) which resembles morphine in its action but according to Ott is depressant to the spinal cord and about twice as depressant to the respiratory centre. For these reasons it is inferior to morphine as an analgesic. Its manufacture or importation is forbidden in the United States. Heroin is a white crystalline powder of bitter taste soluble in 3 parts of water and in II parts of 9o% alcohol. Its most important medical use is as a respiratory sedative to allay cough in doses of one-sixteenth to one-sixth of a grain. At first it was used in place of morphine to avoid the danger of addiction characteristic of morphine but later experience showed that it is fully as dangerous in this respect. It makes addicts quickly; its victims are often mere children in years and experience ; through insuffiation, ingestion or subcuta neous injection its effect is practically instantaneous. According to the prison and police statistics "heroin is the drug used by addicts of over 95% of New York's underworld (criminal classes)" (Hubbard, New York State In. Med., 1924, 24, 62).