Pathological Constituents. 397 



The quantities of uric acid observed in the fasting experiments here reported 

 are unusually small. For the five days of fasting experiment No. 73, the 

 quantities of uric acid per day were 0.172, 0.122, 0.082, 0.059, and 0.054 gram, 

 respectively. It is to be noted, however, that on the last 3 days of the fast, 

 the quantities of sample available for the uric acid determinations were so small 

 as to render the results reasonable estimates rather than accurate determina- 

 tions. The fact remains, however, that remarkably small amounts of uric 

 acid were excreted by this subject on the last 3 days of the fast. With the 1 

 resumption of the ingestion of food, which was of a purin-free nature, i. e., 

 milk, the uric acid excretion increased. On the 3 days of experiment No. 74, 

 in which the subject remained inside the chamber, the uric acid excretion 

 was 0.329, 0.537, and 0.407 gram, respectively. On the first day after the 

 subject left the respiration chamber, when he partook of an elaborate diet 

 of varied nature, the uric acid excretion increased to 0.744 gram. 



In the absence of more complete data, little can be said regarding the uric 

 acid excretion in the fasting experiments here reported, save that the evidence 

 seems to indicate that remarkably small amounts of uric acid are excreted by 

 fasting man after the first one or two days of the fast. This observation 

 agrees in general with that of E. & O. Freund (10) save that the estimated 

 amounts excreted by S. A. B. are considerably less than the quantities for the 

 corresponding fasting days observed on Succi in the Vienna fast. The 

 unusually low uric acid excretion observed in one day fasts by Ranke 79 likewise 

 indicates that during even a short period of inanition the uric acid output may 

 be greatly reduced. 



pathological constituents of the urine. 



Of the ordinary pathological constituents in urine (albumen and sugar) 

 albumen has not been found in any of the long fasts made by Succi, and in 

 but one, E. & O. Freund (10), was sugar present. The observations of 

 Brugsch (12) on acidosis showed the presence of /? oxybutyric acid. 



Careful tests of all the samples of urine of the experiments here reported 

 showed in no instance the presence of albumen or sugar. The large increase 

 of carbon in the urine in experiment No. 77, may, as has been before stated, 

 have been caused by the formation of /3 oxybutyric acid, although no direct 

 evidence of its presence was obtained. 



sulphur. 



Sulphur in the urine is derived almost wholly from the oxidation of the 

 sulphur in the protein molecule, for a very small amount of preformed sulphuric 

 acid is taken with the food or drink. Consequently, as an index of protein 

 katabolism, the total elimination of sulphur in the urine may be of value. 



79 Loc. cit. 



