202 The Feeding of Animals 



by a known volume of water and is thus determined. 

 This is a great advance towards certainty, because 

 direct measurements of the energy of a ration in use 

 are thus made possible and the necessity for theoreti- 

 cal assumptions is largely removed. 



It is already made clear to the reader, doubtless, 

 that the demonstration of facts and principles in the 

 domain of animal nutrition is exceedingly difficult. It 

 should be equally clear that when conclusions . are 

 reached in ways which have been briefly described, 

 they are worthy of respect and should have greater 

 weight than the necessarily imperfect observations of 

 common practice. Science often errs in her deduc- 

 tions, but the efforts of her workers are constantly 

 directed towards the elimination of false conclusions, 

 so that unsound theories are not likely to be accepted 

 for a great length of time. 



