TRANSFORMATION AND EQUIVALENCE OF FORCES. 231 



No. They are of value as disclosing the many particular 

 implications which the general truth does not specify. They 

 are of value as teaching us how much of one mode of force 

 is the equivalent of so much of another mode. They are of 

 value as determining under what conditions each metamor- 

 phosis occurs. And they are of value as leading us to inquire 

 in what shape the remnant of force has escaped, when the 

 apparent results are not equivalent to the cause. 



