EXCHANGE OF MATEKIAL 



INTAKE IN GRMS. 



15 



As we have already shown, it is a matter of indifference in 

 a calculation of the exchange whether we consider the organic 

 substances discharged in the faeces as products of consumption or 

 as non-absorbed remains of food. In the former case, they are 

 included in the output, as is shown in the table ; in the latter 

 case, they must be deducted from the intake. If, following 

 Tigerstedt, we adopt the latter expedient, it would follow that the 

 subject of the experiment had a daily allowance of 89 grins, of 

 protein containing 14*2 grms. of nitrogen, *78'8 grms. of fat, and 

 286'6 grms. of carbohydrate. Since 16'2 grms. of nitrogen were 

 discharged in the urine, there is a deficit of 2 grms. in the balance 

 of nitrogen ; in other words, the subject lost 12 -3 grms. of protein 

 from his own tissues. The total consumption of protein was 

 101/5 grms., while 89 grms. were absorbed; so that the diet 

 contained 12 -5 grms. too little to cover the consumption and 

 maintain nitrogenous equilibrium. 



The table, moreover, shows a gain of 12 grms. in carbon; in 

 other words, the organism accumulated a certain quantity of non- 

 nitrogenous organic substances, containing altogether 12 grms. of 

 carbon. We now have to ascertain whether fats or carbohydrates 

 have been deposited. 



