LVIII. <i>On the masses of the ions in gases at low pressures</i>

Abstract

I N a former paper (Phil.Mag.Oct. 1897) I gave a deter- mination of the value of the ratio of the mass, m, of the ion to its charge, e, in the case of the stream of negative electrification which constitutes the cathode rays.The results of this determination, which are in substantial agreement with those subsequently obtained by Lenard and Kauhnann, show that the value of this ratio is very much less than that of the corresponding ratio in the electrolysis of solutions of acids and salts, and that it is independent of the gas through which the discharge passes and of the nature of the electrodes.In these experiments it was only the value of m/e which was determined, and not the values of m and e separately.It was thus possible that the smallness of the ratio might be due to e bei!lg greater than the wdue of the charge carried t)y th3 ion m electrolysis rather than to the miss m being very much smaller.Though there were reasons for thinking that the charge e was not greatly different from the electrolyric on% and that we had here to deal with masses smaller than the atom~ yet, as these reasons were somewhat indirect, I desired if possible to get a direct measurement of either m or e as well as of role.In the case of cathode rays I did not