URINE AND ITS CONSTITUENTS. 



727 



small filter, previously dried at 110 C. (230 F.) and weighed ; wash with boil- 

 ing water to which a little ammonia water has been added (to remove uric 

 acid and urates), then with pure water until the filtrate is not rendered turbid 

 any longer by silver nitrate, next with pure alcohol, and finally with ether. 

 Dry filter and contents at 110 C. (230 F.) and weigh. 



As it may happen that the precipitated albumin encloses earthy phosphates, 

 it is well to burn filter with contents in a platinum crucible, and to deduct the 

 weight of the remaining inorganic residue (less the weight of the filter ash) 

 from that of the albumin. 



Serum-globulin is detected by rendering the urine alkaline with 

 ammonia water, filtering off the precipitate of phosphates, and add- 

 ing to the clear filtrate an equal volume of a saturated 

 solution of ammonium sulphate. The appearance of a FIG. 75. 

 precipitate indicates globulin. 



Albumoses answer to the nitric acid test and the 

 potassium ferrocyanide test for albumin ; the precip- 

 itate formed by these reagents dissolves on heating, 

 but reappears on cooling. Albumoses are further rec- 

 ognized thus : To the urine strongly acidified with hydro- 

 chloric acid is added an equal volume of a saturated so- 

 lution of sodium chloride. On boiling, serum-albumin, 

 if present, is precipitated and filtered off while hot. 

 Albumoses separate from the filtrate on cooling. 



The solution, filtered while hot, gives a red biuret 

 reaction. As albumose is frequently present in albu- 

 minuria, its demonstration is important only in the 

 absence of albumin. Albumosuria occurs with the 

 absorption of purulent exudates, in acute yellow atrophy 

 of the liver, and in other conditions. 



Peptones are not uncommonly present in the urine aibuminometer. 

 in albumosuria, but are rarely present alone. Peptonuria 

 exists when it is possible to obtain a red biuret reaction after the 

 careful removal of protein and albumose. Both here and in the case 

 of albumosuria urobilin may mislead one when the biuret reaction is 

 tried. It may be removed by extraction with alcohol. 



Bence- Jones body is present in the urine in certain cases of 

 bone disease (multiple myeloma). It is thought to be a unique 

 albumin and not an albumose, as held by the earlier view. It is 

 coagulated in urine acidified with acetic acid on heating to 50 or 

 60 C., and redissolves as the temperature reaches the boiling-point. 

 It is very rarely present. 



Esbach's 



