The Natural and Artificial Disintegration of the Elements

The Natural and Artificial Disintegration of the Elements is an address by Professor Sir Ernest Rutherford, given on the occasion of the centenary celebration of the founding of the Franklin Institute, September 17, 18, 19, 1924. The address says it is not the speaker's intention in this paper to give a detailed account of the natural disintegration of the radio elements or of the methods employed to effect the artificial disintegration of certain light elements.

The address calls the minute but massive nucleus, in a sense, a world of its own which is little, if at all, influenced by the ordinary physical and chemical forces at our command. The address also says that the movements of the outer electrons are responsible for the X-ray and optical spectra of the elements, and that from a study of the radioactive transformations the nucleus of a heavy atom not only contains positively charged bodies but also negative electrons. The address discusses the energy of the shortest wave measured in this way by Ellis, which corresponds to more than two million volts.