372 APPENDIX. — horsfall's system. 



will be about one third of a pound, which is assimilated 

 in increase of fibrin, and represents only one and one 

 third to two pounds of substances rich in protein, 

 beyond what is required for her maintenance. 



If we examine the effects on the fertility of the land, 

 my milch cows, when on rich pasture, and averaging a 

 yield of nine quarts per day, and reckoning one cow to 

 each acre, will carry off in twenty weeks twenty-five 

 pounds of nitrogen, equal to thirty of ammonia. The 

 same quantity of milk will carry off seven pounds of 

 phosphate of lime in twenty weeks from each acre. 



A fattening animal, gaining flesh at the rate I have 

 described, will carry off about one third of the nitrogen 

 (equal to about ten pounds of ammonia) abstracted by 

 the milch cow, whilst if full grown it will restore the 

 whole of the phosphate. 



It is worthy of remark that experience shows that 

 rich pastures, used for fattening, fully maintain their fer- 

 tility through a long series of years, whilst those used 

 for dairy cows require periodical dressings to preserve 

 their fertility. 



If these computations be at all accurate, they tend to 

 show that too little attention has been given to the sup- 

 ply of substances rich in nitrogenous compounds in the 

 food of our milch cows, whilst we have laid too much 

 stress on this property in food for fattening cattle. 

 They tend also to the inference that in the effects on 

 the fertility of our pastures used for dairy purposes we 

 derive advantage not only from the phosphate of lime, 

 but also from the gelatine of bones used as manure. 



On comparing the results from my milch cows fed in 

 summer on rich pasture, and treated at the same time 

 with the extra food I have described, with the results 

 when on winter food, and whilst wholly housed, taking 

 into account both the yield of milk and the gain of 

 weight, I find those from stall-feeding full equal to those 

 from depasture. The cows which I buy as strippers, for 

 fattening, giving little milk, from neighboring farmers 

 who use ordinary food, such as turnips with straw or 

 hay, when they come under my treatment increase their 



