Metabolism Experiment No. 59. 



29 



designated " material other than urea." The urea may roughly be computed * 

 by dividing the number of grams of nitrogen eliminated by 46.6, the percentage 

 of nitrogen in urea. For the 3 days of this experiment it was computed to be 

 25.43, 30.15, and 31.70 grams for the respective days. Given, then, the total 

 solids of urine and the number of grams of urea (obtained by dividing the 

 nitrogen by 46.6), by subtracting from the total solids of urine the number 

 of grams of urea, the " material other than urea plus ash " is obtained. 



Thus on the first day of the experiment the amount of total solids was 

 computed to be 46.3 grams. Deducting from this the amount of urea for the 

 first day, i. e., 25.43 grams, leaves 20.87 grams as the weight of "material 

 other than urea plus ash." The corresponding figures for the second and 

 third days are 24.65 grams and 26.00 grams. Assuming, then, that the 

 " material other than urea " is constant, the ash is obtained as follows : Total 



Table 4. Weight and composition of urine Metabolism experiment No. 59 



(December, 1903). 



Weight 



Water 



Solids, ab 



Ash i 



Organic matter, cd 



(/) Nitrogen 



(g) Carbon 



(h) Hydrogen in organic matter 



(i) Oxygen (by difference) in organic mat- 

 ter, e-(f+g + h) 



(a) 

 (6) 

 (c) 

 (d) 

 ie) 



Dec. 18-19. 



Grams. 



1540.8 



1494.5 



46.3 



6.94 



39.36 



11.84 



8.71 



2.60 



16.21 



Dec. 19-20. 



Grams. 



981.8 



927.0 



54.8 



8.20 



46.60 



14.11 



10.40 



3.11 



18.98 



Dec. 20-21. 



Grams. 



928.9 



871.2 



57.7 



8.67 



49.03 



14.82 



10.92 



3.26 



20.03 



Total 

 for 3 days. 



Grams. 

 3451.50 

 3292.7 

 158.8 

 23.81 

 134.99 

 40.77 

 30.03 

 8.97 



55.22 



1 The ash and water for the individual days are calculated as shown on p. 28. Hence the amounts 

 of solids and organic matter for the individual days are not determined but calculated. 



" material other than urea plus ash " for 3 days is to the " material other than 

 urea plus ash " for any given day as the total ash is to the ash for any given 

 day. Thus, the sum of the " material other than urea plus ash " for the 3 

 days is 20.87 -f- 24.65 + 26.00 = 71.52 grams. The proportion, then, would 

 be 71.52 : 20.87 : : 23.81 (total ash determined for the three days of the 

 experiment) : 6.94 grains, the amount of ash for the first day. By means of 

 this proportion the values for ash for the two following days were found to be 

 8.20 and 8.67 grams, respectively. 



Method of obtaining water in urine in experiment No. 59. The amount of 

 water of the urine was determined on the 3-day composite in this experiment. 

 In order to compute the amounts excreted each day, the figures for the total 

 amount of urine for each day were decreased by the corrected amount of total 



1 It is known that probably at least 1 gram of creatinine is excreted aside from 

 the urea. Hence the calculation is at best but approximate. 



