Radio-Activity
PREFACE TO THE FIRST EDITION.
In this work, I have endeavoured to give a complete andconnected account, from a physical standpoint, of the propertiespossessed by the naturally radio-active bodies. Although thesubject is comparatively a new one, our knowledge of the propertiesof the radio-active substances has advanced with greatrapidity, and there is now a very large amount of information onthe subject scattered throughout the various scientific journals.
The phenomena exhibited by the radio-active bodies areextremely complicated, and some form of theory is essential inorder to connect in an intelligible manner the mass of experimentalfacts that have now been accumulated. I have found thetheory that the atoms of the radio-active bodies are undergoingspontaneous disintegration extremely serviceable, not only incorrelating the known phenomena, but also in suggesting newlines of research.
The interpretation of the results has, to a large extent, beenbased on the disintegration theory, and the logical deductions tobe drawn from the application of the theory to radio-activephenomena have also been considered.
The rapid advance of our knowledge of radio-activity hasbeen dependent on the information already gained by researchinto the electric properties of gases. The action possessed by theradiations from radio-active bodies of producing charged carriersor ions in the gas, has formed the basis of an accurate quantitative