142 Rutherford: Modern 



This result, as we shall see, is most simply explained 

 by supposing that the charge carried by a hydrogen atom 

 is a natural and indivisible unit of electricity, and that 

 the various ions may carry a charge which is an integral 

 multiple of this unit charge. For example, an atom of 

 oxygen carries a charge of two units, of gold three, and 

 of tin four. 



Quite apart from their practical aspect, the results 

 obtained by Faraday were of the greatest importance in 

 indicating that there was a close relation between elec- 

 tricity and matter, and that electrical manifestations must 

 be ascribed, not to matter in bulk, but to the atoms or 

 molecules composing it. In addition they clearly showed 

 that the currents obtained from the voltaic battery re- 

 sulted from the charges set free by the chemical decom- 

 position of the substances employed. 



The full theoretical significance of Faraday's work 

 was not recognized until nearly half a century later, 

 when Helmholtz and Weber suggested that the results 

 of electrolysis were very simply explained by supposing 

 that electricity was atomic in structure. On this view, 

 electricity, like matter, is not infinitely divisible, but 

 appears in definite small lots, as it were, which cannot 

 be further subdivided. This natural unit of quantity of 

 electricity is the charge carried by the hydrogen atom in 

 the electrolysis of water, and every quantity of electricity 

 must be an integral multiple of this natural unit. It is 



