WHAT IS PHYSICAL LIFE 



accretion, but never by the working of 

 complex, internal organization. No thing 

 on earth can grow unless it be living. So 

 no force or forces can shape any form of 

 matter so that it will reproduce itself. 

 Force and matter can make an icicle, but 

 the icicle remains as lifeless as both the 

 force and the matter which produced it. 



But a new and portentous factor in the 

 problem now challenges our consideration, 

 namely, that of Heredity. Again, as al- 

 ready mentioned, in the wonderful or- 

 ganization of this minute particle of whale 

 matter we find that in a minuter portion 

 of it, namely its nucleus, there is a minuter 

 portion of this in turn, which goes by the 

 name of the chromatin substance, and that 

 this latter substance chiefly bears the in- 

 delible impress of all the whale's ancestry 

 back to the first whale. On that account 

 this whale, as he grows, will demonstrate 

 that whales used to walk, for in his adult 



