COMPOSITION OF MANURE. 137 



is generally very small. In the case of the fattening 

 animals, 96 per cent., or more, of the ash constituents of 

 the food find their way into the manure. With fatten- 

 ing oxen and sheep, and with horses, more than 95 per 

 cent, of the nitrogen of the food are voided in the 

 manure. The pig is seen to retain a much larger pro- 

 portion of the nitrogen of its food, about 85 per cent, 

 appearing in the manure. The milking cow gives the 

 best return in saleable produce for the nitrogen which 

 it receives, only about 75 per cent, appearing in the 

 manure. With diets containing a smaller amount of 

 albuminoids the proportion of nitrogen appearing as 

 manure will of course be diminished. 



The amount of nitrogen voided in the urine is seen to 

 be always greater than the quantity contained in the 

 solid excrement, and is generally three or four times as 

 much. This relation will vary according to the character 

 of the diet. If the food is nitrogenous, and easily 

 digested, the nitrogen in the urine will greatly pre- 

 ponderate ; if, on the other hand, the food is one imper- 

 fectly digested, the nitrogen in the solid excrement may 

 form the larger quantity. When poor hay is given to 

 horses, the nitrogen in the solid excrement will exceed 

 that contained in the urine. On the other hand, corn, cake, 

 and roots yield a large excess of nitrogen in the urine. 



The ash constituents are very differently distributed 

 in the solid excrement and urine ; in the former is found 

 nearly all the phosphoric acid, and the greater part of the 

 lime and magnesia, while the latter contains the greater 

 part of the potash. With sheep and horses, and probably 

 more or less with other animals, a part of the potash is 

 excreted in the perspiration. 



