CHAPTER X 



THE LAW OF THE CONSERVATION OF ENERGY " LAWS " 

 OF NATURE ENERGIES OF LIFE MATTER AND 

 FORM 



IN this chapter it will be necessary briefly to touch 

 upon a difficulty in connection with the vitalistic 

 view of living nature which has often been raised 

 and forms the subject of quite a considerable 

 literature. 



This is the difficulty presented or supposed to Law of 

 be presented by the Law of the Conservation of 

 Energy. 



Physical energy, that is to say the capacity for 

 doing work, may be of two kinds. It may be kinetic 

 or in actual evidence as it is in a flying bullet or a 

 moving railway-train, or it may be potential or not 

 evident to the careless eye as it is in a suspended 

 weight. Now many experiments have been made 

 respecting these different kinds of energy and 

 respecting the different varieties of energy of which 

 we shall have to speak shortly, and as a result of 

 these experiments the following facts emerge or 

 appear to emerge. 



First of all it seems perfectly clear that when 



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