Metabolism Experiment No. 59. 



39 



then equal the original quantities of elements lost. The mathematical verifi- 

 cation of these computations is shown in table 9. 



Two features of this table demand special discussion. In the first place, while 

 the actual amount of ash determined by chemical analyses is seen in table 4 

 to have been 6.94 grams/ here it is seen that only 5.85 grams of ash were 

 katabolized. On the other hand, it must be borne in mind that in the 71.04 

 grams of protein katabolized there were 1.09 grams of ash, since protein con- 

 tains 1.53 per cent of mineral matter. It is necessary, therefore, to deduct from 

 the total amount of ash in the output, 6.94 grams 6 in this particular experiment, 

 the total amount of ash in the protein, 1.09 grams, since the ash of the kata- 

 bolized protein appears in the urine. Therefore the difference, 5.85 grams, 

 is ash other than ash of protein. 



In the second place, while it has been stated above that the sum of the 

 elements in these compounds, as computed from their percentage composition, 

 should equal the quantities of elements lost, there are slight discrepancies, 

 amounting to but 0.1 or 0.2 of a gram, which are due to the dropping of 



Table 10. Elements and materials katabolized in the body Metabolism experiment 



No. 59. 



1 See pp. 28-29. 



supernumerary figures in the computations. The agreement is sufficiently 

 close, however, to demonstrate the mathematical accuracy of the computation of 

 the protein, fat, glycogen, water, and ash katabolized. 



Elements and materials katabolized in the tody. As a result of the com- 

 putations cited above, we have not only the amounts of the chemical elements 

 lost from the body, but also the chemical compounds expressed in terms of 

 water, protein, fat, carbohydrates, and ash. These are shown in table 10 

 for each day of the experiment. The figures for the first day are also shown in 

 table 9. 



By inspection of the figures for the daily amounts it is seen that, save in the 

 case of the carbohydrates, about the same quantities of materials were lost on 



6 In this particular experiment the quantity of ash was calculated, not determined. 

 See p. 28. 



