XXIX 



THE EVOLUTION OF MATTER 



By W. C. D. Whetham, M.A., F.RS. 



Trinity College, Cambridge. 



The idea of evolution in the organic world, made intelligible by 

 the work of Charles Darwin, has little in common with the recent 

 conception of change in certain types of matter. The discovery that 

 a process of disintegration may take place in some at least of the 

 chemical atoms, previously believed to be indestructible and unalter- 

 able, has modified our view of the physical universe, even as Darwin's 

 scheme of the mode of evolution changed the trend of thought con- 

 cerning the organic world. Both conceptions have in common the 

 idea of change throughout extended realms of space and time, and, 

 therefore, it is perhaps not unfitting that some account of the most 

 recent physical discoveries should be included in the present 



volume. 



The earliest conception of the evolution of matter is found in the 

 speculation of the Greeks. Leucippus and Democritus imagined 

 unchanging eternal atoms, Heracleitus held that all things were in a 

 continual state of flux — UdvTa pel. 



But no one in the Ancient World — no one till quite modern times 

 — could appreciate the strength of the position which the theory of 

 the evolution of matter must carry before it wins the day. Vague 

 speculation, even by the acute minds of philosophers, is of little use 

 in physical science before experimental facts are available. The true 

 problems at issue cannot even be formulated, nuich less solved, till 

 the humble task of the observer and experimenter has given us a 

 knowledge of the phenomena to be explained. 



It was only through the atomic theory, at first apparently dia- 

 metrically opposed to it, that the conception of evolution in the physical 

 world was to gain an established place. For a century the atomic 

 theory, when put into a modern form by Dalton, led farther and farther 

 away fiom the idea of change in matter. The chemical elements 



