Section III., 1914. [9] Trans. R.S.C. 



Modern Views on the Constitution of the Atom. 



By Dr. A. S. Eve, F.R.S.C. 

 (Read May 26, 1914). 



At a meeting of the Royal Society of Canada held at Montreal, 

 May, 1914, the writer gave by request a summary of recent work 

 and ideas on the nature of the atom. The object was to concentrate, 

 as clearly as possible, but not exhaustively, the results and opinions 

 scattered through many different publications. Few men have time 

 or opportunity to collect and analyze for themselves the large out- 

 put bearing on this fascinating subject. 



(1). It may be well to call attention to the general bearing of 

 the situation. Biologists are divided into three camps — vitalists, 

 mechanists, and those who sit on the boundary fence. The mechanists 

 believe that all phenomena relating to life are attributed to the action 

 of physical and chemical processes only. The vitalists believe that 

 life involves something beyond and behind these. Now those who 

 investigate natural philosophy, or physics, are endeavouring with 

 some fair initial success, to explain all physical and chemical pro- 

 cesses in terms of positive electrons, negative electrons, and of the 

 effects produced by these in the ether, or space devoid of matter. 



If both the mechanists are right, and also the physicists, then 

 such phenomena as heredity and memory and intelligence, and our 

 ideas of morality and religion are explainable in terms of positive and 

 negative electrons and ether. All of these speculations are really 

 outside the domain of Science, at least at present. 



(2). It has been remarked by Poincaré that each fresh discovery 

 in Physics adds a new load on the atom. The conditions which the 

 atoms have to explain may indeed be written down, but to do so is 

 merely to make a complete index for all books on Physics and Chemis- 

 try in the widest sense. 



(3). In the early days of the Kinetic Theory of Gases, now well 

 established in its broad outlines, it was sufficient to regard the atom 

 as a perfectly elastic sphere, and it is not a generation ago that lead- 

 ing savants were triumphantly determining the effective radius as 

 about 10~ 8 cm. (a convenient shorthand for the hundred millionth of a 

 centimetre). 



The discovery of electrons, as the cathode rays of an electric 

 discharge in an exhausted tube, and as the beta rays of radium, 



