PREFACE Vli 



agricultural experiment stations, and afford some in- 

 dication of the direction and value of the work done 

 by these institutions. 



In the preparation of Chapter XIII, valuable assist- 

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

 Dairy Expert of this station. 



L. L. VAN SLYKE. 

 New York Agricultural 

 Experiment Station, 1906. 



