By the usual test for radioactivity, i.e., the continued ionization of a gas independent of other physical conditions, sodium as an element does not display any activity that is definitely greater than that found in all matter. And the ionizing activity of ordinary matter is so slight that it cannot be stated with definiteness whether or not the matter is of itself radioactive. But radioactivity implies a more fundamental change than that of emitting matter and energy continuously. It implies an atomis disintegration. If α particles are emitted the atoms go by leaps and bounds to new atoms of other properties, while if β and ν radiations are emitted the wearing away of the atoms must be just as certain, though no one has been able to conjecture by what steps the changes may take place.
Proceedings of the Iowa Academy of Science
©1912 Iowa Academy of Science, Inc.
Brown, F. C.
"Evidence Favoring the Radioactive Disintegration of Sodium as an Element,"
Proceedings of the Iowa Academy of Science, 19(1), 175-178.
Available at: https://scholarworks.uni.edu/pias/vol19/iss1/31