182 SIR WILLIAM RAMSAY 



are formed. We may next ask what mechanism can be devised 

 to give us a picture of the union of two atoms ? . . . Various 

 chemists have called the mechanism by which it is conceived 

 that atoms remain associated in a compound 'affinities' or 

 4 bonds,' and ' valency ' is a word used to express the number 

 of such ' bonds ' which an element can exercise in any particular 

 combination. I have to bring before you a suggestion which, 

 although not exactly new, admits of definite statement, and affords 

 a mental picture of what may conceivably take place. It is 

 not a ' theory ' ; I do not hope that it may be true ; it is rather 

 a hypothesis, a supposition that I expect to be useful ; it may be 

 a ' make-believe ' ; I trust that it will not be a ' mistake.' 



The hypothesis admits of short statement. It is : electrons 

 are atoms of the chemical element electricity ; they possess 

 mass ; they form compounds with other elements ; they are 

 known in the free state, that is, as molecules ; they serve as 

 the ' bonds of union ' between atom and atom. The electron 

 may be assigned the symbol E." 



Ramsay then proceeded to quote from the Faraday 

 lecture given before the society by Helmholtz in 1881 

 and a lecture by Nernst twenty years later. Both these 

 authorities supported the idea of the dual nature of 

 electricity. Ramsay, however, proposed to revert to 

 the " one fluid " idea of Benjamin Franklin which has 

 gained probability since the investigations of J. J. 

 Thomson and the discovery of radio-active bodies. 



"It has been shown that electric corpuscles or electrons are 

 capable of detaching themselves from matter and inhabiting 

 space unattached to any object. . . . The electron may be 

 termed an atom of negative electricity. The atom which it 

 has left is generally, and by many supposed to be always, posi- 

 tively electrified. . . . 



