190 . INORGANIC EVOLUTION. ['CHAP. 



Professor J. J. Thomson is thus led to the following view of the 

 differences of construction of a simple " atom " and a compound 

 " molecule " : 



" In the molecule of HC1, for example, I picture the components of 

 the hydrogen atoms as held together by a great number of tubes of 

 electrostatic force ; the components of the chlorine atom are similarly 

 held together, while only one stray tube binds the hydrogen atom to 

 the chlorine atom." 



Dr. Preston's results on the magnetic perturbation of lines, to 

 which I have already referred, leads him to the same general conclu- 

 sions as those arrived at by Professor J. J. Thomson in favour of the 

 view of dissociation. He says : 



" It may be, indeed, that all ions are fundamentally the same, and 

 that differences in the value of e/m, or in the character of the vibra- 

 tions emitted by them, or in the spectral lines produced by them, may 

 really arise from the manner in which they are associated together in 

 building up the atom." 



The Three JVays of Inorganic Evolution. 



At the present time, then, we have before us three suggested ways 

 of inorganic evolution. 



Taking the chemical view, this may depend on 



(1} Polymerisation, or the combination of similar chemical mole- 

 cules; or 



(2) The combination of dissimilar chemical molecules. 

 In the new physical view all this is changed into 



(3) The gradual building up of physical complexes from similar 

 particles associated with the presence of electricity. 



In this last conception we have the material world, up to the 

 highest complex, built up of the same matter under the same laws ; as 

 in spectrum analysis there is no special abrupt change between the 

 phenomena presented by the simple and compound bodies of the 

 chemist, so also in the new view there is no break in the order of 

 material evolution from end to end. I have already, on p. 167, 

 referred to the opinions expressed by Professor J. J. Thomson and 

 Dr. Preston, as to the manner in which the new work supports my 

 view expressed many years ago. 



Certainly the new view seems competent to throw light on many 

 facts which lacked explanation on the old one, by whatever method of 

 evolution the higher complexes were assumed to be brought about, 

 because on the ionic theory we can imagine several first forms, so 

 that the question of descent comes later" with the introduction of more 



