PREFACE vii 



agTiciiltiiral experiment stations, and afford some in- 

 dication of the direction and value of the work done 

 by these institutions. 



In the preparation of Chapter XIV, vahiable assist- 

 ance has been kindly rendered by Mr. George A. Smith, 

 Dairy Expert of this station. 



L. L. Van Slyke. 

 Nezv York Agricultural 

 Experiment Station, 1906. 



