1936

Ernest Lawrence and colleagues complete work on “cyclotron,” which facilitated production of radioactive isotopes, enable isotopic techniques to test function of thyroid gland, pumping activity of heart, etc. (Reiser, 219). First investigations with radioactive iodine, I128, at MGH thyroid clinic; First therapeutic use of artificially produced radioisotopes on Christmas eve; (Lenoir & Hays, 31).