The charges on ions in gases, and the effect of water vapour on the motion of negative ions

1. In a paper published in the ‘Proceedings of the Royal Society,’ vol. 80, p. 207, January, 1908, a method was given for comparing the charges on ions in liquids and gases. The first set of experiments gave results in accordance with the theory, and it was found that the charge on a positive ion in a gas was double that of a negative ion, the latter being equal to the charge on a monovalent ion in a liquid electrolyte. The ratio of the charges obtained was 2.4 / 1.23. The ions were produced by secondary Röntgen rays emitted by a brass surface, and further experiments have shown that positive ions with double or single atomic charges may be produced, the number of either kind depending on the nature of the secondary rays, which is determined by the state of the metallic surface from which they originate.