Correspondence

Two subjects have recently been irradiated under controlled conditions with about 0·05 rad of partially moderated 14 MeV neutrons to permit studies of the induced radioactivity (Anderson, Osborn, Tomlinson, Newton, Rundo, Salmon and Smith, 1964). During these four irradiations (anterior and posterior for each subject) X-ray film was placed behind the subject to ascertain whether it showed any response to the small dose of neutrons emerging from the subject, and if so with what result.