Winner of the 1935 Nobel Prize in Physics; discovered the neutron for the atomic bomb. ALS signed “J. Chadwick,” one page both sides, 8 x 10, personal letterhead, July 28, 1971. Letter to a Mr. Solomon. In part, “I gave a general account of the discovery and the steps leading to it for an International Congress of the History of Science held at Cornell in 1962…I was convinced that the neutron must exist in the atomic nucleus in order to explain the structure of the atomic nuclei, convinced by many discussions with the late Lord Rutherford. For about 9 years, I tried at intervals, and by different means, to obtain evidence of its existence. On some occasions I looked in the right place but my equipment was not good enough. Then later I was given some old radon tubes…From these I obtained polonium for use as a source of particles. With such a source of H. C. Webster, a research student, made a very interesting study of the radiation excited in beryllium by the bombardment of particles. This convinced me that the radiation consisted if neutral particles…Then M. and Mme Curie-Joliet made an even more striking observation that this radiation from Be would project protons from matter containing hydrogen…I just got this news as I was beginning to repeat Webster’s observation in a different way. Almost within hours I was able to convince myself that the radiation consisted of neutrons as I had expected.” Accompanied by the original mailing envelope. In fine condition, with two horizontal mailing folds. COA John Reznikoff/PSA/DNA and R&R COA.
