December 7, 1910-April 4, 1980

BY ROY J. BRITTEN

Dr. Richard Brooke Roberts spent most of his career in the biophysics group at the Department of Terrestrial Magnetism of the Carnegie Institution of Washington. Dick contributed importantly to many scientific advances in this period in microbiology, the beginnings of molecular biology, and study of the brain. One high point was the proof (with Kenneth McQuillen and me) that in Escherichia coli, protein synthesis occurred on ribosomes. Dick also named the ribosome. Dick started out as a nuclear physicist and among several discoveries showed that delayed neutrons were emitted in uranium fission (1939,5). This discovery was of great practical consequence because delayed neutrons slow the responses in a pile enough to permit control by mechanical movement of cadmium rods. This made fission piles practical for all of their uses in weapons making as well as power. As a result, Dick was involved in early planning of what became the Manhattan Project, although he decided that it was too long range a project for the emergency. He chose to work on more practical weapons and showed that vacuum tubes would survive being fired from a gun; he also developed a radio-controlled proximity fuze which made antiaircraft guns very effective (the first ''smart" missile), forever changing