Nitrogen in Urine. 375 



A comparison of the data for the total 24 hours of a given experiment 

 shows that in general large volumes of urine are accompanied by large amounts 

 of nitrogen. For the consecutive days of each experiment this is generally 

 true but no comparison is permitted for different experiments. This general- 

 ization is true for the large majority of the fasts. Especially is it true in the 

 first 3 days of experiment No. 69, and the whole of experiments Nos. 71, 73, 

 75, 81, and 82. On the other hand, there are striking contradictions noticed 

 more especially in experiment No. 77. In this experiment the largest volume 

 of urine appears on the first day and is coincident with the smallest excretion 

 of nitrogen, while on the last day the smallest volume of urine is accompanied 

 by the largest excretion of nitrogen. A similar statement holds true for 

 experiment No. 59. (See table 3.) 



In considering this question, it is doubtful whether the 2-day experiments, 

 influenced as they undoubtedly are by the food of the day before, can be 

 considered as of much value. It thus appears that, while in the majority of the 

 experiments it may be reasonably inferred that there was an increased elimi- 

 nation of nitrogen coincident with large volumes of urine, on the other hand, 

 the data of experiments Nos. 59 and 77 render the conclusion doubtful. 



The influence of drinking large quantities of water on the nitrogen excretion 

 has been studied very carefully, the majority of the experiments, however, 

 having been made with animals. All of the observations have demonstrated 

 that with increased volume of urine there is an increased nitrogen excretion. 

 The results have, however, permitted of two interpretations of the cause of 

 the increase, and scientists have differed in their belief. According to one view 

 the increase is due simply to the flushing out of the urea and other products 

 preformed in the tissues, while the other maintains that the drinking of large 

 amounts of water results in a stimulated protein katabolism. The more 

 recent investigations of Hawk," and Heilner, 56 have considered this problem 

 in a more elaborate manner, stating not only the excretion of nitrogen but 

 also of phosphorus, sulphur and chlorides. 



An examination of the more recent experimental evidence leads to the 

 conviction that experiments on fasting men especially with complete urine 

 analyses would aid materially in settling this much disputed point. In spite 

 of the fact that in several of the experiments here reported unusually large 

 amounts of drinking-water were consumed, the conditions under which these 

 experiments were made are such as in our judgment to preclude any direct 

 conclusions regarding the influence of increased consumption of water on 

 nitrogen excretion. It is important, however, in considering the causes for the 

 variations in the nitrogen excretion on the different days, not to overlook the 

 fact of the possible influence of the varying amounts of water consumed. 



58 Univ. of Pennsylvania Medical Bulletin (1904). 

 56 Zeit. f. Biol. (1906), 47, p. 538. 



