Г)36 DR. W. 0. MOOR, 



1) Ureiue 6 7o Urea almost imperceptible. 



2) Ureine 7 % % , Urea 0,33 7o. 



3) Ureiue 5,4%, UreaO,G9%. 



4) Ureiue 8%, Urea 0,17. 



5) Ureine 5 %. 



It is evident, tlierefore, tliat fhe same error wliicli bas been committed 

 rcgarding the normal iirinc lias also been made witli diabetic uriue. The 

 trutli of tliis can be easily proved in the followiug mauuer: Let us take a 

 diabetic urine, wliicli after filtration has a pale-yellow color; the more pro- 

 uouuced the yellow color is, the more satisfactory will be the results ob- 

 taiued. Now we détermine tlie perceutage of the urea in two dififereut ways: 



1) In the usual way, with Hypobromite of Soda. 



2) We take 10 cbcm. of this uriue, dilute thera with 50 cbcm. water 

 and add a sufficieut amouut of Potassium Permanganate to completely oxi- 

 dize the Glucose and the Ureine; it requires usually about two or three 

 gramms of KaMugOg to each 10 cub. centim. of urine to eftect this. After 

 one or two days we filier and evaporate at 50° C; we treat the residue 

 with absolute alcohol aud evaporate the latter: 



The amount of urea thus obtained will he insignificant compared with 

 the iKrcentage resulting from the usual methods. 



The procédure of isolating ureiue from the urine of diabetics is différ- 

 ent from the raetliod whicli I recommended for normal urines. We take 

 ouly such diabetic urine which after filtratiou hasadistinctly yellow color'). 

 The urine is evaporated at 45 — 50° С until а syrupy residue remaius, 

 which does not diminish any further in volume on a prolonged exposure to 

 a température of 45° С. — Alcohol cannot be used in these cases, as glu- 

 cose and ureine are so intimately mixed tliat they cannot be separated by 

 alcohol. 



On letting stand, however, this syrupy liquid in a testtube for 24 

 hours (at ordinary température) a sédiment of glucose and of minerai mat- 

 ters will form; the testtube is theu left for auother few hours in ico, as a 

 low température hastens the séparation of urea and of other solid consti- 

 tuents. Finally the ureine is decantered or filtered. The apjiroximative 

 perceutage of diabetic ureine can be fouud by weighing the whole syrupy 

 residue and by dcducting therefrom the weight of glucose, of urea and of 

 sait, as calculated from saraples of the same urine. It is hardly necessary 



1) Diabetic urinn is always colorless in au ordinary testtube, but frequently shows я yel- 

 low color in а wider bottle; this yellow color of diabetic urines dépends on the présence of 

 ureine. 



Физ.-Мит. стр. '-Зб. 8 



