ENERGY IN GENERAL. " 85 



morphoses being governed by two laws equally 

 inevitable, the conservation of matter and the con- 

 servation of energy. The first of these laws expresses 

 the fact that matter is indestructible, and passes 

 from one phenomenal determination to another at 

 a rate of equivalence measured by weight; the 

 second, that energy is indestructible, and that it 

 passes from one phenomenal determination to another 

 at a rate of equivalence fixed for each category by 

 the discoveries of the physicists. 



§ 6. Transformations of Energy. 



The idea of energy has become the point of departure 

 of a science, Energetics, to the establishment of which 

 a large number of contemporary physicists, among 

 whom are Ostwald, Le Chatelier, etc., have devoted 

 their efforts. It is the study of phenomena, regarded 

 from the point of view of energy. I have said that it 

 claims to co-ordinate and to embrace all other sciences. 



The first object of energetics should be the con- 

 sideration of the different forms of energy at present 

 known, their definition and their measurement. This 

 is what we have just done in broad outline. 



In the second place, each form of energy must be 

 regarded with reference to the rest, so as to determine 

 if the transformation of this into that is directly 

 realizable, and by what means, and, finally, according 

 to what rate of equivalence. This new chapter is a 

 laborious task which would compel us to traverse the 

 whole field of physics. 



Of this long examination we need only concern 

 ourselves here with three or four results which will be 



