234 BOARD OF AGRICULTURE. 



practical farmers consists in his earnest endeavor to bring 

 the valuable results of previous scientific research within the 

 reach of the practical farmer. 



Although personally fully convinced of the fact that 

 much had yet to be learned in regard, not only to the intri- 

 cate relations which seemed to exist between the various 

 proximate constituents of plants, and their special functions, 

 in case of various classes of animals, but also in regard to 

 the influence of the individuality of different animals of the 

 same kind, as well as of different breeds, on the feeding 

 effect of one and the same article of fodder, &c, he felt 

 confident that enough had already been proved, by science 

 and practice, to furnish useful lessons for farm-practice. 



He concluded, that with the recognition of the importance 

 of the four nutritive groups for the support of animal life, 

 and with the knowledge of the chemical composition of 

 our fodder-crops, useful lessons for farm-practice might be 

 drawn from a closer study of the best feeding experiments 

 on record, by ascertaining the relative amount of the nutri- 

 tive principles which the animal on trial had consumed. 

 He ascertained in some ninety carefully conducted feeding 

 experiments (his own included) the exact amount of the 

 various kinds of fodder substances which the animal on trial 

 had consumed within a given time. He calculated, subse- 

 quently, from the chemical composition of the fodder used in 

 the trial, the absolute and relative amount of nitrogenous 

 and of non-nitrogenous substances, fat, and mineral matter, 

 the animal had received for different purposes in a definite 

 period. The results obtained were tested in practice, as 

 far as possible, to ascertain their exact value. Where prac- 

 tical experience did not yet furnish the exact basis for fur- 

 ther deduction, the next best mode, to judge from analogy, 

 was resorted to in order to aid in the work. Fully con- 

 vinced that future experience would modify some of his 

 rules for feeding different lands of stock, he presented in 

 1859 the summary of his labors to the consideration of 

 practical farmers, as a starting-point for a more rational and 

 economical mode of feeding their farm live-stock. As cir- 

 cumstances do not permit me to enter upon a detailed dis- 

 cussion of Grouven's directions for fodder-mixtures, I insert 

 here a few revised directions, of a more recent date, which 



