THE SEARCH FOR PRIMAL MATTER 



to that of uranium, around two hundred times as 

 heavy. 



Yet the atoms of the different elements, varying 

 so widely in their weights, their reactions to light, 

 heat, and so forth, seem curiously alike when it 

 comes to carrying electricity through water. Each 

 one carries the same charge, or just twice or thrice 

 it. It was this fact which proved such a stumbling- 

 block to the acceptance of Professor Thomson's 

 results. 



What the latter found was that the ratio be- 

 tween the amount of electricity carried by an atom 

 in a water solution and the mass of that atom was 

 a thousand times less than the ratio between the 

 mass and charge of the particles of a cathode ray. 

 It might have been inferred from this that the 

 charge carried by a cathode ray was a thousand 

 times that carried ordinarily by an atom, and, 

 therefore, that the atom and the particle of the 

 cathode rays were one and the same. But Pro- 

 fessor Thomson was able to show that the charge 

 of electricity in the two cases was identical. It 

 follows, then, that the cathode -ray particle is a 

 thousand times smaller than the smallest of chemi- 

 cal atoms. 



It was clear, therefore, that these minute bodies 



:ed a name, and, taking a leaf from Newton's 



note-book, Professor Thomson called them cor- 



159 



