His technical interests continue to relate to the safety of nuclear explosions and their effects on man, his structures, his environment. and Eric T. Clarke received his Ph.D. in nuclear physics at MIT in 1944. In 1949 he participated in a program for long-range detection of nuclear explosions that succeeded in identifying the first Russian detonation through fallout analysis. From 1956 to 1967 he was in charge of, or closely associated with, various research studies performed by Technical Operations, Inc. for the predecessors of the Defense Nuclear Agency and the Defense Civil Preparedness Agency to determine the probable deposition and the radiation characteristics of fallout. He helped to organize a weapons effects group for, and in 1966 was the chairman of, the American Nuclear Society's Shielding Division. Frank Cluff joined the Weather Bureau in 1946 as a Weather Observer. He continued in that employment for over 20 years, except for time out to obtain a B.S. degree in 1950 and an M.S. degree in 1956, both in meteorology at the University of Utah. In 1967 he joined the AEC, becoming Deputy Test Manager at the AEC's Nevada Test Site. He is now retired. Robert E. Heft received his Ph.D. in physical chemistry at the University of Chicago in 1953. He has engaged in research concerning the physical and chemical properties of the particle populations generated by nuclear detonations. He was with the Air Force Technical Application Center until 1963 and since that time has been with the bio-environmental group at Lawrence Livermore Laboratory. Carl F. Miller received his M.S. in physical chemistry from the University of California at Berkeley in 1948 and his Ph.D. from Iowa State University at Ames in 1951. He has been concerned with research on the formation, distribution, and deposition of fallout and the hazards due to the radiations therefrom as well as on various civil defense coutermeasures to provide protection against these hazards. He participated in research projects covering several nuclear weapon field-test operations at the Nevada Test Site and at the Pacific Proving Grounds in the period of 1952 to 1962. These activities and research on civil defense subjects were performed while Dr. Miller was employed by the U.S. Naval Radiological Defense Laboratory, the Office of Civil Defense (as an Assistant Research Director), and the Stanford Research Institute; Dr. Miller is presently a staff member of The Dikewood Corporation. ea rq II-2