266 PRINCIPLES OF ANIMAL NUTRITION. 
Legth Heat Production. 
or | eee Resp. |_—_______ 
Subject. Food. Experi- sd,| 2%°- | Ob- | Com- | Comp 
ment, | SU™MeC,! tient. ‘ ; 
: | Liters. serv’d,|puted |-+- Obs. 
Hours. | *t¢ Cals. | Cals. | % 
p Nate guinea-pigs...) Third day of fasting.. 8 8.112] 0.791 | 37.106) 37.315) 100.6 
Rabbit.... ........ Second day of fasting... 5t 7.650] 0.752 | 35.254) 35.190) 99.8 
DUCK e6: ssa: sseiniaie s Fasting for 2 days... 4 8.800] 0.750 | 40.375) 40.480} 100.3 
Dog (2 expts.)... Hf 2and 4 days. 124 30.205] 0.758 }141.366/138.943] 98.2 
Average of all : 
Fasting empts..| 220: ccccerescdecras sa ceeelestessee 82.812) 0.766 |385.403/380.935) 98.8 
Two dogs.......... 300 grms. of meat....... 20 51.683] 0.816 |239.431/237.741| 99.2 
Guinea-pigs. * 2 AC lenis exes 31.787) 0.917 |155.787|154.230| 99.0 
Rabbits Mixed diet rich in 30 46.445) 0.893 |227.086/224.050} 98.6 
Duck carbohydrates 8 21.603) 0.885 |105.911/104.040] 98.2 
Dogs 66 180.398] 0.973 |882.580/887.197] 100.5 
with the aid of the respiration-calorimeter of Atwater & Rosa (p. 
248), and in addition to the great pains bestowed to obtain accurate 
results are especially distinguished by the fact that all the quantities 
involved were, so far as possible, subjected to direct measurement, 
estimates being avoided with the necessary exception of the poten- 
tial energy of the gain or loss by the body. The sublingual or 
axillary temperature of the subject was also measured in every case. 
The following results of one of the earliest experiments (No. 5) may 
serve to illustrate the general features of them all: 
Income, Outgo, 
‘als. Cals. 
Hinerey of LOO: 5:0 4-s:se: od: ever eecre aunty wo veected hovers 2655 
GOS > AE FOC Sis: a rastauislvayd avers cvauarevous © Souk wa “ahey Sree 143 
5 MUTE ae sah ax a ee Shade we esate Pe 128 
Loss by body: 
PrOteltiwsi/ine bate hawaii eee Gay ieawes Bes —24 
Hath: chong be tinek oh RMON See oink Baad eee sts —73 
Heat production ........... 0... cece cece ee eee Secteps 2379 
Balance wii c's Salcim sags deena aw seins 45 eon anaes ita 102 
2655 2655 
Aside from the loss of 97 Cals. by the body as computed from the 
carbon and nitrogen balance, all the quantities in the above state- 
ment represent actual determinations of energy and the account 
balances within 102 Cals., which is 3.8 per cent. of the total energy 
of the food or 4.1 per cent. of the computed heat production. To 
put the matter in a slightly different way, the heat production as 
computed by Kellner’s method (p.255) from the carbon and nitrogen 
balance and the energy of food and excreta exceeds by 102 Cals. 
