PPwEFACE. V 



labor as mucli as is possible witliout tlie saeriiiee of act'iiraej 

 and a reasonable degi'ee of fulness. Above all, lie Ixas souglit 

 to make liis work a reliable exponent of tlie i>resent state of 

 knowledge on tlie subject of cattle-feeding, and to draw a sharp 

 line between proved and useful facts, and merely probable 

 bypotlieses or speculations. 



This book was begun as a translation of Wolff's " Land- 

 wirthschaftUche FuUenrngdehre,'^ a volume of some two hun- 

 dred pages. It was soon found, however, that considerable 

 additions and changes were required to suit it to Ameri- 

 can readers, and the work has finally assumed its j)resent 

 form. Some portions of it are still free translations of Wolflt; 

 but much more of it has been either added or entirely re- 

 written, and a number of illustrations have been introduced, 

 so that the character of the book has been considerably 

 altered. One of the most marked changes is the substitution, 

 in the Ax^pcndix, of Kiihu's tables of the composition and 

 digestil)ility of feeding-stuffs for those of "Wolff. Although 

 the writer does not accept all of Klilm's opinions, he yet 

 believes that tables arranged on the -plan adopted by Kulm 

 are, on the whole, preferable to those containing simiDly aver- 

 ages ; and in view of the changes and additions made else- 

 where in the volume, he has felt justified in making the sub- 

 stitution named, though aware that Kuhn's views, on some 

 points, are warmly opposed by Wolff. 



In addition to the '' FiUterungslehre" the author is espe- 

 cially indebted to Wolff's larger book, " Die Ernalirung der 

 landwiHhschaftUchen Nidzihkrer while other works and the 

 current literature of the subject have been freely consulted. 



HErT. 1, 1880. 



