ORGANIC SULPHUR COMBINATIONS. 753 



upon the extent of the sulphuric-acid excretion. According to HARNACK 

 and KLEINE/ the relation of the oxidized sulphur to the total sulphur 

 changes always in the same way as the relation of the nitrogen of the 

 urea to the total nitrogen. The more unoxidized sulphur is eliminated 

 the more abundant are the nitrogen compounds, not urea, in the urine 

 a statement which coincides with recent observations showing that the 

 neutral sulphur originates chiefly from the different proteic acids, and 

 the uroferric acid. 



According to LEPINE, a part of the neutral sulphur is more readily oxidized 

 (directly with chlorine or bromine) into sulphuric acid than the other, which is 

 only converted into sulphuric acid after fusing with potash and saltpeter. The 

 investigations of W. SMITH 2 show that it is probable that the difficultly pxidizable 

 part of the neutral sulphur occurs as sulpho-acids. An increased elimination of 

 neutral sulphur has been observed in various diseases, such as pneumonia, cystin- 

 uria, and especially where the flow of bile into the intestine is prevented. 



The total quantity of sulphur in the urine is determined by fusing the solid 

 urinary residue with saltpeter and caustic alkali or sodium peroxide, or by oxida- 

 tion with nitric acid. 3 The quantity of neutral sulphur is determined as the 

 difference between the total sulphur and the sulphur of the sulphate and ethereal- 

 sulphuric acids. The readily oxidizable part of the neutral sulphur is determined 

 by oxidation with bromine or potassium chlorate and hydrochloric acid (LEPINE, 

 JEROME 4 ). 



Sulphuretted hydrogen occurs in the urine only under abnormal conditions 

 or as a decomposition product. This compound may be produced from the 

 neutral sulphur of the organic substances of the urine by the action of certain 

 bacteria (Fn. MULLER, SALKOWSKI 5 ). Other investigators have given hypo- 

 sulphites as the source of the sulphuretted hydrogen. The occurrence of hypo- 

 sulphites in normal human urine, which is asserted by HEFFTER, is disputed by 

 SALKOWSKI and PRESCH. 6 Hyposulphites occur constantly in cat's urine and, 

 as a rule, also in dog's urine. 



Antoxyproteic acid is a nitrogenous acid containing sulphur which 

 BONDZYNSKI, DOMBROWSKI, and PANEK 7 have isolated from human 

 urine. The composition of the acid was: C 43.21, H 4.91, N 24.4, S 0.61, 

 and O 26.33 per cent. A part of the sulphur can be split off by alkali. 

 This acid is soluble in water, is dextrorotatory, and is only precipitated 

 from concentrated solution by phosphotungstic acid. It does not give 

 the protein color reactions, but gives EHRLiCH r s diazo reaction (see below) . 



Benedict, Zeitschr. f. klin. Med., 36; Harnack and Kleine, 1. c.; Folin, Amer. 

 Journ. of Physiol., 13. 



2 Lepine, 1. c.; Smith, Zeitschr. f. physiol. Chem., 17. 



3 See Abderhalden and Funk, Zeitschr. f. physiol. Chem., 58 and 59, which also 

 cites other methods. See S. R. Benedict, Journ. of biol. Chem., 6 and 8; Denis, ibid., 

 8; Gill and Grindley, Journ. Amer. Chem. Soc., 31; Folin, ibid., 31. 



4 Jerome, Pfliiger's Arch., 60. 



6 Fr. Muller, Berlin, klin. Wochenschr., 1887; Salkowski, ibid., 1888. 



6 Heffter, Pfluger's Arch., 38; Salkowski, ibid., 39; Presch, Virchow's Arch., 119. 



7 Zeitschr. f. physiol. Chem., 46. 



