On the La'w of the Nutrition of Animals. 45T 



8788 niaass (3837 quarts). The lime during which they sup- 

 plied milk was 302| days. This gives as a mean 4"l maass 

 (1*8 qt.) daily for each cow. But the quantity of milk varies 

 very much ; for in the months of July and August they yielded 

 above 6 maass (2"64 qts.), while in February and March they 

 gave only about '2^ maass (Tl qt.). From observations of a 

 similar nature, made however upon only one cow, the average 

 daily quantity of milk yielded was 3*7 maass (l'G3 qt.). If we 

 take 2h maass (1*097 qt.) as the lowest quantity, and 7 maass 

 (3*073 qts.) as the highest, we get daily, for one cow, from 

 JO'3 lbs. to 29 lbs. of milk, which contain — 



4 "69 oz. troy to IS'O* oz. butter. 



7*08 20*02 oz. sugar of milk and sol. salts. 



7*88 22*18 oz. caseine and insol. salts. 



Total 19-65 



55*24< oz. solid matter. 



In reference to the influence which the food has upon the 

 quantity of milk, all farmers know that cows give most milk 

 with green food and less with hay, &c. In other respects the 

 influence of the food is not so great as might be expected. 



Boussingault and Le Bel agree upon this point, at least so 

 far as concerns the quantity of milk*. Dr. R. D. Thomson, 

 on the contrary, draws from similar and equally extensive 

 experiments the conclusion, that the quantity of milk and 

 butter increases in proportion to the quantity of nitrogen 

 (contained in the plastic matter) of the food. He has drawn 

 this conclusion from experiments upon two cows during 

 periods of five days. His results are shown in the following 

 table, in which grass is the only exception f. 



* Boussingault has recently found that hay is equally efficacious with 

 grass in producing milk and muscle; a result which is certainly not appli- 

 cable to hay made in usual seasons in this country. — Tr. 



•t f)"". Thomson attributes the superiority of grass to the proper balance 

 of the proximate principles, which in hay and grain is much altered by the 

 drying process. — Tr. 



X In Dr. Knapp's work the number taken from the original is lOG. The 

 present number has been recalculated from the original data. — Tr. 



