Products of uranium fission which are chemically antimony, tellurium and iodine have been examined. The following activities have been found: Three activities—the 10-hour tellurium, the 70-minute tellurium, and the 8-day iodine—have been identified with known bodies through comparison of half-lives and beta-ray spectra. Genetical relationships of the activities have been established by a technique of periodic separations and by the observation of growth in activity curves.

• Received 11 May 1939

DOI:https://doi.org/10.1103/PhysRev.56.1