376 PHYSIOLOGICAL CHEMISTRY. 



all the acid is converted into anhydride. The anhydride may then 

 be further purified. 



Organic combinations containing sulphur of unknown kind, which may in 

 small part consist of sulphocyanides, 0.04 (GSCHEIDLEN) 0.11 p. m. (J. 

 MUNK), cystin, or bodies related to it, and protein bodies, are found in human 

 as well as in animal urines. The sulphur of these mostly unknown combina- 

 tions has been called " neutral," to differentiate it from the "acid " sulphur 

 of the sulphate and ethereal-sulphuric acids (SALKOWSEJ). The neutral sul- 

 phur in normal urine as determined by SALKOWSKI is 15$, by STADTHAGEN 

 13.3-14.5$, and by LEPINE 20$ of the total sulphur. An increase in the quan- 

 tity of neutral sulphur has been observed in icterus (LEPINE), and in cystin- 

 uria (STADTHAGEN). 



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

 urinary residue with saltpetre and caustic alkali. The quantity of neutral 

 sulphur is determined as the difference between the total sulphur and the sul- 

 phur of the sulphate and ethereal sulphuric acids. 



Sulphuretted hydrogen occurs in urine only under abnormal conditions or 

 as a decomposition product. Sulphuretted hydrogen may be produced from 

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

 certain bacteria (FR. MULLER, SALKOWSKI). Other investigators (ROSENHEIM 

 and GUTZMANN) have given hyposulphites as the source of the sulphuretted 

 hydrogen. The occurrence of hyposulphites in normal human urine, which 

 is asserted by HEFFTER, is disputed by SALKOWSKI. In cat's and dog's urine 

 the hyposulphites are, on the contrary, constant. 



Organic combinations containing phosphorus (glycero-phosphoric acid, etc.), 

 which yield phosphoric acid on fusing with saltpetre and caustic alkali, are 

 also found in urine (ZULZER, LEPINE, EYRONNET, and AUBERT). 



Enzymes of various kinds have been isolated from the urine. Among these 

 we may mention pepsin (BRUCKE and others), diastatic enzyme (COHNHEIM and 

 others), and rennet (GRUTZNER, HOLOVTSCHINER, HELWES). The occurrence 

 of trypsin in the urine is doubtful. 



Substances similar to mucin (nucleoalbumin ?) from the urinary passages 

 and the bladder are generally present in the urine, though in very small 

 amounts. According to several investigators (LEUBE, HOFMEISTER, POSNER), 

 normal human urine also contains traces of albumin. 



Ptomaines and leucomaines or poisonous substances of an unknown kind, 

 which are often described as alkaloidal substances, occur in normal urine 

 (PoucHET, BOUCHARD, ADUCCO, and others). Under pathological conditions 

 the quantity of these substances may be increased (BOUCHARD, LEPINE and 

 GUERIN, VILLIERS, and others). Within the last few years the poisonous 

 properties of urine have been the subject of more thorough investigation, 

 especially by BOUCHARD. He found that the night urine is less poisonous 

 than the day urine, and that the poisonous constituents of the day and night 

 urines have not the same action. 



BAUMANN and v. UDRANSZKY have shown that ptomaines may occur in the 

 urine under pathological conditions. They demonstrated the presence of the 

 two ptomaines discovered and first isolated by BRIEGER putrescine, GMImNa 

 (tetramethylendiamin), and cadaverin, CeHiJSj (pentamethylendiamin) in the 

 urine of a patient suffering from cj^stinuria and catarrh of the bladder. 

 BRIEGER, v. UDRANSZKY and BAUMANN and STADTHAGEN have shown that 

 not only these but other diarnins occur under physiological conditions. The 

 occurrence in normal urine of any "urine poison" is denied by certain inves- 

 tigators, such as FELTZ and RITTER and STADTHAGEN. The poisonous 

 action of the urine, according to them, is due in great part to the potassium 



