INTRODUCTION 3 



if not to the store at least to the advancement of 

 knowledge : and count almost for as little as the 

 one bad experiment whether based upon theory 

 or not. 



Attention is therefore needed in the choice of the 

 path to be pursued as well as in the pursuit itself. 

 Now for our part we do not wish to affirm, nor 

 strictly speaking even to suggest, that the theories 

 herein hazarded and the experiments described to 

 verify them, have been in all cases in the right 

 direction ; what may be affirmed, however, is that 

 some trouble has been taken in deciding on them. No 

 doubt the same end may be reached by divers paths. 



The subject is thus approached, if one may 

 venture to approach it so, from a different stand- 

 point from that which the biologist, trained as he 

 would be in another frame of mind, would naturally 

 have started from. It is attacked from the standpoint 

 of a physicist who endeavours to disclose in many of 

 the phenomena, perhaps more familiar to physicists 

 than to biologists, the striking resemblance between 

 many physical and biological effects. 



The object of this book then is to indicate, and 

 it is hoped also to prove, so far as proof is 

 possible, the continuity of vital processes ; that 

 the links between the organic and the inorganic, 

 between living and dead matter form an unbroken 

 and continuous chain, which connects biology with 

 physics as closely as it unites the two with chemistry. 



The doctrine of spontaneous generation was in the 

 Middle Ages accepted as a fact : and those who may 



B 2 



