THE Hurter memorial lecture was delivered recently before the Liverpool Section of the Society of Chemical Industry, by Dr. C. A. Keane, on modern iatro-chemistry (Journal of the Society of Chemical Industry, Liverpool Section, April 15). Dr. Keane traced the development of various synthetic products used in pharmacy, and discussed the relations of physiological properties to structure so far as they may be said to be known. He illustrated his discourse by three typical groups of compounds-the antipyretics derived from-aminophenol, the hypnotics derived from malonyl urea, and the local anaesthetics related to cocaine. Referring to the first group, he showed that the toxic properties of aminophenol may be reduced and its antipyretic action increased by introducing radicals into the hydroxyl and amina groups. He pointed out the importance of a sufficiently stable combination to resist decomposition by the acid of the gastric juice, as otherwise the radical is split off in the stomach with the production of the parent substance. The practical outcome of these investigations has led to the recognition of phenacetin as the most suitable for medicinal use.