EXCHANGE OF MATEEIAL 



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 grms. of 

 protein containing 14'2 grms. of nitrogen, V8'8 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. 



