PREFACE 



This volume is the result of an effort to present 

 the main facts and principles fundamental to the 

 art of feeding animals, as they are now understood. 

 It is not a statement of rules or of the details of 

 practice, for even if the author regarded himself as 

 competent to discuss these he would hold it to be 

 unwise to attempt to discriminate in practical matters 

 so varied and so complex. 



Neither has an effort been made to harmonize the 

 whole mass of experimental data relating to animal 

 nutrition. Many of these data are of no value, many 

 are verj' incomplete, and many are apparently con- 

 flicting, so that more useful lessons can often be 

 drawn from single events in the field of experiment 

 and investigation than from the frequently doubtful 

 testimony of summaries. 



The author expresses the hope that what he has 

 written will not be regarded as having for its ulti- 

 mate object the mere exposition of feeding formulas. 

 It is to be feared that the German standard rations 

 are unfortunately accepteil l)y manj- as nutrition pre- 



rv) 



