106 Influence of Inanition on Metabolism. 



Ash. While the ash eliminated in the urine steadily increased from day 

 to day as is seen from results recorded in line k of the table, the ash of the 

 food remained practically constant. Consequently, there was a gain on the first 

 day, nearly ash equilibrium on the second day, while there was a marked loss 

 on the third day. On the average the body was practically in ash equilibrium. 



Energy. The object of the balances shown in table 64 is to indicate in how 

 far the losses from the body were compensated by the food ingested and hence 

 the balance which takes into account the energy of these nutrients can also be 

 obtained. Such comparison is shown in the last three lines of the table. 

 In line m is given the energy of food absorbed, i. e., the difference between the 

 energy of food and feces as determined by the bomb calorimeter, while line n 

 shows the total heat production plus the potential energy of the urine (ob- 

 tained from columns b and g of table 53). The differences recorded in line o 

 show that on the first day there was a gain of 213 calories of potential energy 

 to the body, on the second a gain of 131 calories and on the last day a loss of 

 121 calories. On the whole, therefore, the diet supplied somewhat more energy 

 than was actually given off by the body. 



The results obtained in line o require special comment. The figures as given 

 in the table represent the gain or loss to the body of potential energy, not 

 the actual amount of energy which would be gained or lost if the energy 

 of the absorbed food were liberated in the body. Furthermore, the results 

 obtained in line o can not be obtained by multiplying the gain or loss of the 

 nutrients shown in lines c, f, and i by their respective heats of combustion. If, 

 for example, such computations be made the first day of the experiment, 

 the result obtained would be 230 instead of 213 as shown in the table. Thus 

 ( 29.16 X 5.65) + (34.06 X 9.54) + (16.64 X 4.19) = 230. The dis- 

 crepancy between 213 and 230 may be avoided by using in line n in place of 

 2207 calories, 2192 calories, the total energy of the material oxidized in the 

 body plus the potential energy of the urine, and using in line m 2421 calories 

 (energy of absorbed food computed by means of factors for heat of com- 

 bustion, line g, table 62) in place of 2420 calories. The case is exactly the 

 same for the remaining days of the experiment. For showing the gain or 

 loss to the body of potential energy, however, the figures in line o should 

 remain unchanged. 



