CHAPTER III 



ENERGY IN ANIMALS 



Secondary Sexual Characters— Period of Gestation— Cer- 

 tain Characters at Certain Ages— Transformed 

 Energy — Delay in Concentration — Concentration 

 Proportional to Expenditure — Dissipation of Animal 

 Energy— Testing Pedigrees for Concentration of 

 Energy — Lines of Limitation. 



SO far, the general principles of Physics 

 (known as the science of energy) are the 

 same in biology as they are in mechanics. 

 The difference between biology and me- 

 chanics lies in the difference in the manner of 

 applying these principles and not in the 

 principles themselves, or in the manner of 

 measuring the energy involved in the princi- 

 ples. Before we turn to the facts of record 

 for the purpose of determining the accuracy 

 of the reasoning and conclusions previously 

 set forth, it is necessary for us to consider a 

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