CHARLES G. DARWIN (1887 - 1962). The Theory of X-ray Reflexion. (Philosophical Magazine 1914, 27, 315-333.)
Darwin made contributions to science in three different, although related, areas of activity: (1) theoretical research in optics (particularly X-ray diffraction), atomic structure, and statistical mechanics; (2) educational and scientific administration; (3) world sociological and technical problems, with special reference to population.
Darwin studied mathematics at Cambridge University, and then became a postgraduate student with Ernest Rutherford (1871 - 1937) at Manchester. He began research on the absorption of alpha rays and for a time showed interest in the dynamics of Rutherford's nuclear atom model. He soon turned to X-ray diffraction as a subject on which he could exercise his mathematical powers and, after some experimental work with H. G. J. Moseley (1887 - 1915), produced a series of papers on this topic, of which The Theory of X-ray Reflexion was the most significant.
After service in World War I, Darwin was appointed fellow and lecturer of Christ's College, Cambridge, a position he held until 1922. The principal fruit of his Cambridge appointment was the collaboration with Ralph Fowler (1889 - 1944) on a new method of developing statistical mechanics, which served as a particularly effective foundation for the later quantum statistics. For this work and his earlier researches, Darwin was elected a fellow of the Royal Society of London in 1922.
From 1924 to 1936 Darwin served as Tait professor of natural philosophy at the University of Edinburgh. Darwin turned his attention to quantum optics and published several papers, particularly in magneto-optics. After a visit to Niels Bohr's (1885 - 1962) institute in 1927, he became interested in the new quantum mechanics and developed a quantum mechanical theory of the electron that proved to be an approximation to P. A. M. Dirac's (1902 - 1984) later relativistic electron theory. This was another high point in Darwin's scientific career.
In 1936 Darwin became master of Christ's College, Cambridge, but in 1939 he succeeded Lawrence Bragg as director of the National Physical Laboratory, a post he held until his retirement in 1949, having been knighted in 1942. The last fifteen years of Darwin's life were devoted largely to the problems of science and society. He paid much attention to the sociological implications of the population explosion.
Complete Dictionary of Scientific Biography. Detroit: Charles Scribner's Sons, 2008, v3, p563-565.