ИЗВ-БСТ1Я ИМПЕРАТОРСКОЙ АКАДЕМШ НАУКЪ. 1901. МАЙ. Т. XIV, № 5. 



(Bulletin de l'Académie Impériale des Sciences de St.-Pétersbourg. 

 1901. Mai. T. XIV, № 5.) 



Further studies on Ureine, 



the principal organic constituent of the human urine. 



Second communication to the Imperial Academy of Sciences, St.-Petersburg. 



By Dr. William Ovld Moor, of New York City. 



(Presented the 16-th of May 1901). 



First of ail I désire to express my lieartfelt thanks to the Physico- 

 Mathematical Class of the Imperial Academy of Sciences, who received 

 my first coramuuication on aUreine» with such liind interest and had it 

 incorporated in extenso in the minutes (Pi'otokoll) of the meeting of said 

 class on September 6-tli 1900. Since then this subjcct bas been brought 

 before the Academy by Dr. A. Kuliabko ou December 13-th 1900, who 

 critisized my first paper in an impartial and just niauner and fuUy coufirmed 

 the toxicity of the liquid, which I hâve called Ureine. — At the présent 

 moment I can only be thankful for the good fortune that made it possible 

 for Dr. Kuliabko and myself to obtain Ureine. For how could I hâve 

 suspected, that the most eminent meu of science, among them Liebig, liad 

 committed a groat error, wlien they taught, that the human urine con- 

 tained2 — 3% urea and that consequeutly urea was the principal constituent 

 of urine? Indeed it bas taken great moral courage to come to the final con- 

 clusion, that the percentage of urea in the human urine is only 0,5 — 0,8%, 

 îvhereas ureine, the liquid constituent of urine, is présent in quantities of 

 1,5 — 3,4%, so that only the amouut of urea and ureine togcther constitute 

 2 — 3,2% of the human urine. i>ut how did it Imppen, that such an error 

 was committed? The auswer to this question is, that tlie total amount of 

 ureine and urea bas been taken for urea alone. This is evident from the 

 fact, that some of the reactions of ureine are very similar to those of urea, 

 notably the reactions of ureine with nitric acid, oxalic acid and mercuric 

 nitrate of mercury, Hg(N03)2. The reaction of ureine and nitric acid can 

 best be observed in tiie following way: We let two drops of nitric acid fall 



*пз.-11ат. стр. 131 I 36** 



