ABSTRACT
When certain elements are bombarded by swift αparticles, protons orcare liberated which are attributed to the disintegration of the nuclei of these elements. It is now generally assumed that in such an artificial disintegration of an atomic nucleus an α particle is captured by the nucleus. It appears from this evidence that the process of disintegration of an aluminium nucleus by and a particle of given energy is not exactly the same for each individual nucleus. We may explain this most simply by assuming that the energy change W is not the same in each disintegration. The discrepancy can be removed if we suppose that the energy change in the disintegration is not constant. The suggestion that all nuclei of the same element do not have identical masses, which we have advanced from considerations of the energy relations in artificial disintegration, is supported by evidence from the natural disintegration of the radioactive elements.
