Nuclear Physicist. Lecturer in Physics at Cavendish Laboratory and Fellow of Sidney Sussex College, Cambridge, 1934-1943. At Cavendish worked closely with C. T. R. Wilson, professor of natural philosophy, and under him became responsible for development of the 1 million volt H T set, and the direction of its experimental program. 1939-1945: Superintendent of the Telecommunications Research Establishment at the Ministry of Aircraft Production at Swanage and Malvern, and was responsible for the development of the use of the magnetron for centimetric radar. FRS, 1941; OBE, 1943; CBE, 1946. Appointed Regius Professor of Natural Philosophy at the University of Glasgow, 1943; made Professor Emeritus upon his retirement in 1972. During appointment secured funds to purchase an HT set similar to that at Cambridge, and later for a 300 MeV electron synchrotron, for which he supervised design and construction. Member, Advisory Council of the Department of Scientific and Industrial Research, 1947-1952; awarded Hughes Medal, Royal Society, 1952.