Allen D. Allen’s letter about Leo Szilard’s radiation treatment (February 2001, page 82) prompts me to offer some more information on the story Allen had heard.

It was not Jonas Salk but Maurice Goldhaber, then director of Brookhaven National Laboratory, who provided Szilard with isotopes for irradiation of his bladder cancer in 1960 (see page 25 in this issue for more on Goldhaber). Salk and Szilard were conspiring at the time, but not about medical isotopes; their collaboration led to the founding, two years later, of the Salk Institute for Biological Studies, where Szilard was one of the first fellows.

I discovered this while researching Genius in the Shadows: A Biography of Leo Szilard, The Man Behind the Bomb (U. of Chicago Press, 1994), which I wrote with help from Szilard’s brother, Bela Silard. For details about the treatment, see especially chapter 26.