Transcription: I made in 1919 some experiments to test whether any evidence of transformation could be obtained when alpha particles were used to bombard matter. When alpha particles were used to bombard gas oxygen, no new effect was observed. Whenever nitrogen gas was substituted, a number of scintillations were observed far beyond the distance of travel of the alpha particles. Special experiments showed that these scintillations were produced by charged hydrogen atoms, which we now call protons. The appearance of fast protons in these experiments could only be explained by supposing that they arose from th ...
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