New YorK AGRICULTURAL EXPERIMENT STATION. 55. 
observations by Kellner.* He found the average loss of methane 
to be 4.2 grams per 100 grams of digested carbohydrates. As 
1 gram of methane represents 13.246 Cal., this energy loss 
equals 55.633 Cal. for each 100 grams of digested carbohydrates. 
The data showing the loss of energy in the urine present some 
interesting considerations. In the first place they add to the 
evidence already secured by Rubner, Henneberg, Kuhn and 
Kellner; that the old methods of calculating urine energy on the 
assumption that the nitrogen exists wholly as urea and that the 
amount of nitrogen multiplied by 5.343 Cal. repesents all the 
urine energy, is greatly in error. The figures which follow make 
it clear that the heat value of the urine solids may be several 
times that resulting from the old method of calculation. 
ACTUAL HEAT VALUE OF URINE COMPARED WITH CALCULATED VALUE. 
Cow 12. Cow 10. 
First period. Seeond perieee Third period. ane 
Calcu- Calcu- 
Energy as lated, N Energy as lated, N Energy as Calculated, Energy as Calculated, 
deter- in urineX deter- in urinexX deter- N in urine deter- Nin urine 
mined. 5.343 Cal. mined. 5.843 Cal. mined. 5.343 Cal. mined. > 5.343 Cal. 
Cal. Cal. Cat. Cal. Cal, Cal. Cal, Cal. 
1585.6 438.6 1692.1 486.9 1486.3 352.8 
1631.7 455.9 1616.3 458 
1544.6 419 1480.2 416.3 1435 344.6 
1704.1 490.1 1541.1 417.9 1871.6 236.1 1418 346.2 
1682.8 526.5 1800.5 227.4 1454.9 374.5 
1443.3 389.7 ~ 1294.6 221.4 1409.6 348 . 4. 
1801.2 501.5 1510.38 3887.1 1827.3 244.2 157 378.8 
1462 349.5. 
1534.4 378.8 
1498.7 363.6 
It appears that the actual heat value of the urine solids was 
from three to four times as large as the value calculated on the 
basis of nitrogen as urea. This is explained by the fact that a 
variety of solids exist in the urine, quite a percentage of which 
are not nitrogenous. 
It is also evident from the succeeding figures that the heat 
value of urine bears no constant relation to its nitrogen content. 
*Landw. Vers. Stat., 53: 420. 
tSee Zeit. f. Biol., 21: 250. Neue Beitrage, &c., p. 119. 
Landw. Vers. Stat., 44: 348, 404, 474, 529. 
Ibid., 47: 283, 308. 
Also Bul. 42, Pa. State College Expt. Sta., pp. 148-150. 
