A. J. Clark was born at Glastonbury in Somerset. His father, Francis Joseph Clark, the Quaker head of a manufacturing firm, sent him to Bootham School, York, and King’s College, Cambridge, where he gained a first in natural sciences, taking his B.A. degree in 1907. He qualified from St. Bartholomew’s Hospital two years later and was given house appointments there and at Addenbrooke’s, Cambridge. He next obtained appointments in pharmacology at King’s and University Colleges, London, and Guy’s Hospital, but on the outbreak of war enlisted in the R.A.M.C. After the armistice, Clark, who had been awarded the Military Cross for gallantry in France, became professor of pharmacology at Cape Town University. He returned to London in 1919, however, to accept the same chair at University College. In 1926 he was appointed professor of materia medica at Edinburgh University. He was a member of the Medical Research Council from 1934 to 1938 and from 1939 till his death. His best known works were Applied Pharmacology (1923), Comparative Physiology of the Heart (1927), Mode of Action of Drugs on Cells (1933) and General Pharmacology (1938). In his attempts "to bridge the gap between pharmacology and therapeutics" (to use his words), he revealed a wide knowledge of subjects vital not only to the scientist but also to the practitioner. Clark accumulated, too, a vast lore of medical bizarrerie; the dilution of a certain drug as recommended by Hahnemann, he discovered, "works out at a content of 1 molecule of drug in a sphere with a circumference equal to the orbit of Neptune". He produced a devastating tract on Patent Medicines in the popular " Fact" series. Clark saw action again in the 1939—1945 War, being evacuated from Dunkirk, and was at the height of his powers when he died suddenly in 1941. He was a shy, sometimes almost incoherent, man, yet an admirable professor who preserved his spirit of eager enquiry into middle age, took a broad view of his subject and was unassuming and sympathetic towards his pupils, with whom he could hold his own at fives or squash. He married in 1919 Beatrice Powell, daughter of Dr. Hazell of Cape Town, and had two sons and two daughters. He died in Edinburgh.

G H Brown

[Lancet, 1941; B.M.J., 1941]