EXPERIMENT WITH MAN. 



189 



Solving these equations in terms of N, C, H, and O, the following 

 formulae are obtained : 



Protein = 6.0 N 



Fat = 0.005 C + 9-693 H i. 221 O 2.476 N 

 Carbohydrates = + 2.243 C 16.613 H + 2.093 O 2.892 N 

 Water = 1.248 C+ 7.920 H + 0.128 O + 0.460 N 



Substituting for the elements in these formulae the quantity of each 

 gained or lost as expressed in grams in Table 1 2 , and performing the 

 calculations, gives the weights of the compounds gained or lost. In 

 the following illustration the figures are taken from the data for the 

 first day of the experiment (Table 12). Thus : 



Protein = 6 N 



= 6 (4.86) 

 = 29.16 



indicating that 29.16 grams of protein were lost on that day. Again : 



Fat = + 0.005 C + 9.693 H 1.221 O 2.476 N 



= + 0.005 (-I7-94) +9-693 (18.12) 1.221 (161.48) 2.476 (4.86) 

 = + 0.090 175.637 + 197-167 + 12.033 



indicating that 33.65 grams of fat were lost on that day. The results 

 for carbohydrates and water are derived in the same way from the 

 other two formulae. 



The results as thus computed are given in the bottom division of 

 column (a) of Table 12. The correctness of the computations is tested 

 mathematically as follows : From the total weight of each compound 

 gained or lost and its percentages of the elements assumed in the tabular 

 statement above, the quantities of the elements gained or lost are com- 

 puted. The total for each element thus derived should be the same 

 as the difference between the income and outgo of the same element. 



The gains or losses of material expressed in terms of chemical ele- 

 ments and protein, fat, carbohydrates, and water are summarized in 

 Table 13. 



TABI,B 13. Gain or Loss of Elements and Protein, Fat, Carbohydrates, and Water, 

 Metabolism Experiment No. 70. 



