Even in work that lies so near the fortuities of animate nature as dairying, stock−breeding, and the improvement of crop plants, a determinate, reasoned routine replaces the rule of thumb. By mechanical control of his materials the dairyman, ., selectively determines the rate and kind of the biological processes that change his raw material into finished product. The stock−breeder's aim is to reduce the details of the laws of heredity, as they apply within his field, to such definite terms as will afford him a technologically accurate routine of breeding, and then to apply this technological breeding process to the production of such varieties of stock.
