43 
Table 40. — Weight, composition, and heat of combustion of feces — Metabolism experi- 
ment Xo. 14. 
Lab- 
ora- 
tory 
No. 
Weight p Carbo- Xi r Hvdrn Heat of 
. of Water - te Fat - , h >-" ^en Sn Jen COI ? bus - 
leces. drates. - ge • tion. 
2974 Total. 4 days.. 
Average, lday 
Grams. 
Grams. Grams. Grams. Grams. Gram*. Grams. Grams. Calories. 
162.3 21.4 14.7 12.7 3.43 29.52 4.04 328 
54.7 40.6 .3.4 3.7 3.2 .86 7. 3S 1.01 S2 
The amount and composition of the urine during this experiment 
are shown in Tables 41 and 42. As usual, the urine was collected in 
6-hour periods, from which composite samples were made for the 
whole day. 
After the urine for the 6-hour periods had been analyzed for nitro- 
gen in the usual way. the small remaining- portions were, as has been 
the custom, discarded, although the daily composite samples and the 
total composite sample for 4 days were saved until all possibility of 
their being required for future analysis had passed. Immediately 
after the urine for the 6-hour periods had been discarded, it was 
discovered that there were certain errors in the determinations of 
nitrogen, which rendered the results more or less uncertain. The 
nitrogen was redetermined in the total composite, and the results of 
these redeterminations appear in Table 41. These results are used in 
the calculation of the outgo of nitrogen instead of the sum of those 
in <i-hour periods, inasmuch as the latter, although in most case- 
very nearly the same, are thought to be. if anything, less accurate. 
The heat of combustion of the total composite sample of urine for 
the 4 clays of this experiment was determined soon after its close, but 
the determinations of the daily composites were, as explained in the 
description of the previous experiment, unavoidably postponed so 
long that the urine had partially decomposed. The heat of combus- 
tion of the urine for each day in this experiment is therefore com- 
puted in the same way 8 as the carbon, hydrogen, and water-free sub- 
stance. The urine was not collected after the close of the experiment. 
U. 8. Dept Agr.', Office of Experiment Station* Bui. 69, p. 35. 
