Metabolism Experiment No. 70. 



101 



comparable to that which would be expected to arise from the oxidation of 

 1.09 grams of organic hydrogen. It is more than likely that the somewhat 

 higher values for the heat of combustion per gram of body protein, fat, and 

 glycogen result from a rearrangement of the molecules of the corresponding 

 compounds of the food, either by cleavage or condensation in such a manner 

 that there is no loss of energy resulting from the transformation. 



While any attempt to set forth mathematically, as is here done, the trans- 

 formations by the body of the elements of food into body materials must, in 



Table 60. Amounts of ingredients of food absorbed, and corresponding amounts 

 of body materials Metabolism experiment No. 10. 



the present state of our knowledge of physiological chemistry, be regarded as 

 distinctly speculative, for the purposes of this discussion, the mathematical 

 verification and explanation of the apparent discrepancy are of interest. 



Amounts of ingredients of food absorbed and corresponding amounts of 

 body materials. Of special interest in this connection is a comparison between 

 the amounts of ingredients of food absorbed as determined by the usual method 

 of deducting the quantities of protein, fats, and carbohydrates in the feces 

 from the corresponding amounts in the food, and the quantities of body 

 material computed in the foregoing calculations to .have been absorbed. This 

 comparison is shown in table 60. For convenience, the amounts of protein, 

 fat, carbohydrates, and ash in the food and feces are repeated in columns a 

 and h from table 56. The nutrients and ash absorbed, in terms of food 



