LATEK YEAKS 183 



Now I would argue that in the light of modern knowledge we 

 must suppose that the terms ' positive ' and ' negative ' mean 

 merely ' minus electrons ' and ' plus electrons ' ; that the sodium 

 ion or ' sodion ' is an element, that the metal sodium is a com- 

 pound of the element ' sodion ' with an electron ; that the chlorine 

 ion is a compound of an electron (actually of more than one 

 electron) with an atom of chlorine." 



With the use of the symbol E he then proceeded to 

 explain the constitution of common salt, which would 

 be written NaECl, and that of other compounds, and to 

 show in detail how chemical changes must be thought 

 of and how they may be represented. 



The second address to the Chemical Society in 1909 

 treats of the problems connected with the possibility of 

 transmutation of elements into one another. The 

 various arguments are stated in the following words : 



" 1. The subtraction from or addition to an atom of an element 

 of one or more electrons by virtue of which it is converted into 

 an ion completely changes the properties of that element. 



2. The fact is incontestably proved that certain elements 

 termed radio-active are losing electrons, and are thereby being 

 converted into other forms of matter which in our present nomen- 

 clature have equal claim to be considered elementary. 



3. The influence of ultraviolet light on many if not all elements 

 is manifested in causing them to emit electrons ; it is not, how- 

 ever, thereby proved that they yield other elementary forms of 

 matter. 



4. The effect of chemical change is usually manifested in a 

 gain or loss of energy. There is reason to believe that change 

 from one elemental form of matter into another would be accom- 

 panied by an unusually large gain or loss of energy, for it is 

 known that the ' degradation ' of radium is coincident with the 



