380 PRINCIPLES OF ANIMAL NUTRITION. 
reached very nearly 1.00 by the third hour, remaining at substan- 
tially this value for sixteen to eighteen hours and not falling to the 
fasting value in twenty-four hours. Two parallel experiments in 
which 400 grams of meat were fed showed that a part, but by no 
means all, of the above increase was to be ascribed to the 200 grams 
of meat. The small amount of fat given can hardly have affected 
the result. The author estimates that of the total calculated in- 
crease of 22 per cent. over the fasting metabolism about 5 per 
cent. may have been due to the proteids of the food and the 
remainder to the carbohydrates. This conclusion is confirmed by 
the results of two experiments in which rice, sugar, and fat were 
given. The increase in the metabolism was of precisely the same 
character as in the other experiments, but less in amount. 
Tn all these experiments the food was in excess of the fasting 
metabolism. In another series in which the food, consisting of rice, 
either alone or with a small amount of sugar, was about equivalent 
to the fasting metabolism, the increase in the metabolism was 
slightly less, although otherwise the results were similar to those 
of the other trials. 
Computing the results per twenty-four hours, as in the case of the 
fat, we have the following approximate figures for the three series: 
Heat Production in 24 Hours. 
Metab- 
oliza- 
No. of Food ,* ble Increase. 
Experiment. Grms. Energy| Fast- | With 
Food t ing, eee Per 
Cals. a is Cals. | Cent. of 
Food. 
68, 70, Proteids....... 71.3 
71, 73, Carbohydrates. . 375.0 2121 | 1040 | 1271 231 | 10.89 
74, and 75 (| Fat........... 31.0 
Proteids....... 28.1 
84 and 87 | Carbohydrates... 457.5 2226 | 1132 | 1292 | 160] 7.19 
Rat ss ecce8see0 25.0 
Proteids....... 18.75 
107 ...... Carbohydrates. . 225.00 999 991 | 1080 89 8.91 
Faticg va aeevens canes 
* Rice estimated to contain 75 per cent. carbohydrates and 1 per cent. 
nitrogen. 
.{ Computed by the writer, using Rubner’s factors. 
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