58 THE DATA OF BIOLOGY. 



follows from the persistence of force, that each portion of 

 mechanical or other energy which an organism exerts, im 

 plies the transformation of as much organic matter as con 

 tained this energy in a latent state. And on the other hand, 

 it follows from the persistence of force that no such trans 

 formation of organic matter containing this latent energy 

 can take place, without the energy being in one shape or 

 other manifested. 



