406 Conduction in Solutions and Gases, 



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. Wienf 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 per- 

 forations 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 are formed of positively charged 

 particles, obtaining a value of m/e 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 



* The value of m/e for cathode rays was determined also in the same year by 

 W. Kaufmaim, Ann. d. Phys. Ixi, p. 544. 



t Verh;ndl. der physik. Gesells. zu Berlin, xvi (1897), p. 165; Ann. d. Phys. 

 Ixv (1898), {>. 440. 



J Berlin Sitzungsber., 1886, p. 691. Proc. R.S. xlvii (1890), p. 526. 



