4 FORMATION OF THE EARTH 



Lord Rayleigh believed that in the series of elements drawn up 

 by Mendeleef those having the greatest atomic weight are 

 broken up in this way and that the atoms of the lighter metals 

 are their residues. Silver, in this way, can be transformed into 

 lead, lead into carbon, thorium into bismuth, and gold, 

 perhaps, into copper. Thus atoms can be transformed and 

 broken up and made to disappear. 



Since matter can be transformed, and even be made to dis- 

 appear, we have the right to ask how it was able to appear. 

 The phenomena produced in a Crookes' tube, through the 

 walls of which X-rays are able to escape, had practically 

 demonstrated that atoms of matter were far from being 

 simple entities. Among the various hypotheses as to their 

 constitution we may at least accept this — that they are formed 

 of infinitely small masses of matter charged with positive 

 electricity, 1 around which, like satellites round a planet, 

 revolve a very large number of corpuscles, infinitely more 

 minute, whose mass is 1,000 to 2,000 times less than that of an 

 atom of ttydrogen, the smallest known quantity of matter. 2 

 These corpuscles, called electrons, are charged with negative 

 electricity. What, however, do we mean when we say that a 

 thing is charged with such and such a kind of electricity ? 

 Simply that these electrified bodies are centres of attraction 

 or repulsion for other bodies ; that is to say, that they are 

 capable of determining movement ; which they could not 

 do if they were not themselves the theatre of movement. To 

 pass from this to the admission that the electrons and the 

 positive corpuscles are nothing but limited areas of ether and 

 the centre of an active eddying movement, and that 

 electricity is nothing but a manifestation of this vortical 

 motion, is but a step. The nature of electricity then depends 

 simply upon the direction of this movement. Molecular 

 attraction, gravity, attraction of any kind, in brief, are also 

 the consequences of this same movement. 



If the stars are subject to this attraction, it is because its 

 action, like light, is propagated through the medium of the 

 ether, a medium which also transmits the Roentgen rays, the 

 invisible rays of the infra-red and ultra-violet regions of the 



1 II, 218. [In these notes the black Ivoman numerals refer to the 

 Bibliography ; the Arabic numerals to the pages of the works quoted.] 



2 I, 15. 



