Page:A history of the theories of aether and electricity. Whittacker E.T. (1910).pdf/426

 were supposed to be of the same order of magnitude as that on an electrolytic ion, it would be necessary to conclude that the particle whose mass was thus measured is much smaller than the atom, and the conjecture might be entertained that it is the primordial unit or corpuscle of which all atoms are ultimately composed.

The nature of the resinously charged corpuscles which constitute cathode rays being thus far determined, it became of interest to inquire whether corresponding bodies existed carrying charges of vitreous electricity—a question to which at any rate a provisional answer was given by W. Wien of Aachen in the same year. More than a decade previously E, Goldstein had shown that when the cathode of a discharge-tube is perforated, radiation of a certain type passes outward through the perforations into the part of the tube behind the cathode. To this radiation he had given the name canal rays. Wien now showed that the canal rays sure formed of positively charged particles, obtaining a value of immensely larger than Thomson had obtained for the cathode rays, and indeed of the same order of magnitude as the corresponding ratio in electrolysis.

The disparity thus revealed between the corpuscles of cathode rays and the positive ions of Goldstein's rays excited great interest; it seemed to offer a prospect of explaining the curious differences between the relations of vitreous and of resinous electricity to ponderable matter. These phenomena had been studied by many previous investigators; in particular Schuster, in the Bakerian lecture of 1890, had remarked that "if the law of impact is different between the molecules of the gas and the positive and negative ions respectively, it follows that the rate of diffusion of the two sets of ions will in general be different," and had inferred from his theory of the discharge