724 UKINE. 



indoxyl and skatoxyl, pass into the urine as ethereal sulphuric acids 

 after uniting with sulphuric acid. The most important of these ethereal 

 acids are phenol- and cresol-sulphuric acids which were formerly also 

 called phenol-forming substances indoxyl- and skatoxyl-sulphuric acids. 

 To this group also belong pyrocatechin-sulphuric acid, which occurs 

 only in very small amounts in human urine, and hydroquinone-sulphuric 

 acid, which appears in the urine after poisoning with phenol, and under 

 physiological conditions perhaps other ethereal acids occur which have 

 not been isolated. The ethereal sulphuric acids of the urine were dis- 

 covered and specially studied by BAUMANN. X The quantity of these 

 acids in human urine is small, while horse's urine contains larger quan- 

 tities. According to the determinations of v. D. VELDEN the quantity 

 of ethereal sulphuric acid in human urine in twenty-four hours varies 

 between 0.094 and 0.620 gram. C. TOLLENS found an average of 0.18 

 gram. The relation of the sulphate-sulphuric acid A to the conjugated 

 sulphuric acid B, in health, is on an average 10:1. It undergoes such 

 great variations, as found by BAUMANN and HERTER, 2 and after them 

 by many other investigators, that it is hardly possible to consider the 

 average figures as normal. After taking phenol and certain other 

 aromatic substances, as well as when putrefaction within the organism 

 is general, the elimination of ethereal sulphuric acid is greatly increased. 

 On the contrary, it is diminished when the putrefaction in the intestine 

 is reduced or prevented. For this reason it may be greatly diminished 

 by carbohydrates and exclusive milk diet. 3 The intestinal putrefaction 

 and the elimination of ethereal sulphuric acid have also been diminished 

 in some cases by certain therapeutic agents which have an antiseptic 

 action; still the investigators do not agree in their reports. 4 



Great importance has been given to the relation between the total 

 sulphuric acid and the conjugated sulphuric acid, or between the con- 

 jugated sulphuric acid and the sulphate-sulphuric acid, in the study 

 of the intensity of the putrefaction in the intestine under different con- 

 ditions. Several investigators, F. MULLER, SALKOWSKI, and v. NOORDEN, S 



ipfluger's Arch., 12 and 13. 



2 v. d. Velden, Virchow's Arch., 70; Tollens, Zeitschr. f. physiol. Chem., 67; Herter, 

 Zeitschr. f. physiol. Chem., 1. 



3 See Hirschler, Zeitschr. f. physiol. Chem., 10; Biernacki, Deutsch. Arch. f. klin. 

 Med., 49; Rovighi, Zeitschr. f. physiol. Chem,, 16; Winternitz, ibid., and Schmitz, 

 ibid., 17 and 19. 



4 See Baumann and Morax, Zeitschr. f. physiol. Chem., 10; Steiff, Zeitschr. f. 

 klin. Med., 16; Rovighi, 1. c.; Stern, Zeitschr. f. Hyg., 12; and Bartoschewitsch, 

 Zeitschr. f. physiol. Chem., 17; Mosse, ibid., 23. 



5 Miiller, Zeitschr. f. klin. Med., 12; v. Noorden, ibid., 17; Salkowski, Zeitschr. 

 f. physiol. Chem., 12. 



