WHAT IS PHYSICAL LIFE 



repair and that entirely to regenerate are 

 only different degrees of that inherent liv- 

 ing endowment residing in the first micro- 

 scopic cell. 



When a whale is full grown he has mat- 

 ter in quantity sure enough. Every ac- 

 tion then of his nerves, especially his motor 

 nerves, gives rise to electrical currents; 

 every contraction of his muscles liberates 

 heat, and all his secretory activities are ac- 

 companied with chemical changes. But 

 do any of these elements, or all of them 

 together, constitute his life? Not at all. 

 What life he has comes from the life of his 

 primordial cell, and from nothing else. 



But the mysteries of heredity are not 

 confined to the potentialities of the pri- 

 mordial cell. All cells and tissues in the 

 body are ruled by its sway, and can never 

 depart from it. No body cell in a walrus, 

 from its head to its tail, can take on the 

 pattern of a whale's body cell, because 

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