A THEORY OF LIFE 167 



water and carbonic acid, which chiefly make up 

 the atmosphere of a new planet, should simul- 

 taneously occur in the three elements otherwise 

 than through the operation of a natural law 

 which somehow connects them together. There 

 is no greater probability that these unique 

 properties should be without due cause uniquely 

 favourable to the organic mechanism " (J. J. 

 Henderson, 1913). 



If neither of the classic points of view is tenable, 

 what then is the explanation, if, indeed, any be 

 possible ? The author casts one brief glance 

 down that blind-alley marked " Element Way." 

 Does some known element or some unknown 

 element, to which the name Bion might be given, 

 exist and form the source of the energy in living 

 things ? Radium has only been known to us for 

 a few years ; can we say that there is no such 

 thing as Bion ? Of course we cannot ; but this 

 we can say, that, if there is such an element and 

 if it is really responsible for all the protean 

 manifestations of life, wonderful as radium and 

 its doings are, they must sink into nothingness 

 beside those of this new and unsuspected entity. 

 The author evidently does not think that this 

 path is a profitable one to pursue, and we agree 

 with him ; so he turns his attention to the 

 question of energy. Energy is the capacity for 

 doing work. It is often, of course, latent, as, for 

 example, in a cordite cartridge, which is a peaceful, 

 harmless thing until the energy stored up in it is 

 realised with the accompanying explosion and 

 work is done. It is the same with a bent spring ; 



