Philip Abelson discusses his education in chemistry and physics at Washington State University in early 1930s; graduate studies and work on cyclotron under E. O. Lawrence at University of California, Berkeley from 1935-1939; investigations into products of neutron irradiation of uranium; identification of transuranic element 93 with Edwin McMillan; scientific activities at the Department of Terrestrial Magnetism at Carnegie Institution of Washington; work on enrichment of uranium for nuclear submarine project at the Naval Research Laboratory; describes information channels between scientists and government officials during World War II and his perspective on the use of the atomic bomb; continued work at Carnegie by investigating biosynthesis of E. coli using radioactive tracers; as director of Carnegie's Geophysical Laboratory conducted organic geochemical investigations of amino acid decay in Mercenaria mercenaria; co-editor of the JOURNAL OF GEOPHYSICAL RESEARCH; reflections on his editorship of SCIENCE.