304 THE ORIGIN OF LIFE 



ions when produced in a gas by Eontgen or Bec- 

 querel rays, and these are doubtless slow-moving 

 cathode rays. It is a matter of induction that 

 the cathode rays also carry this charge, and there 

 can be little doubt that these also are negative 

 electrons, disembodied atomic charges of electricity 

 of much smaller mass than the atom. 



But of electrons there are two kinds, positive and 

 negative. The word " corpuscle" has been suggested 

 for the smaller or negative electron, as the positive 

 electron is supposed to be made up of the others 

 and to be merely an atom from which a corpuscle 

 has been removed. 



A difficulty, however, remains for which no satis- 

 factory solution has been offered. We are given a 

 number of mutually repelling particles, units of 

 negative electricity — and it is said that they can so 

 form themselves into a community — which as a whole 

 can act as a unit of positive electricity ; and this 

 group of mutually repelling units of negative elec- 

 tricity, it is supposed, will, when acting in concert, 

 attract another similar unit of the same kind, which 

 they all separately and individually repel. 



Still, notwithstanding all this, there are reasons 

 for supposing that the atom is built up of the 

 corpuscles, and that the positive ion is the atom 

 deprived of a corpuscle ; so that the second is 

 merely an aggregate of the first. 



How and in what manner the properties of elec- 

 trons are to be accounted for in this way is a 

 problem which awaits solution. 



