202 THE INCOME OF ENERGY 



to C 2 per cent of a saturated solution of carbolic 

 acid in water. Let B and C stand in a warm 

 place sixteen days. 



2. Withdraw 5 c.c. from flask A. Note 

 whether the urine is clear or turbid, and 

 whether it effervesces on the addition of a 

 dilute acid. Withdraw 2 c.c. from flask A and 

 determine its percentage of urea by the hypo- 

 bromite method. 



Centrifugalize a portion of the remaining con- 

 tents of flask A. With a microscope examine 

 the sediment for crystals of ammonio-magnesium 

 phosphate and for micro-organisms, especially the 

 micrococcus ureae, which occurs in long curved 

 chains of round cells about 1.5 p in diameter. 



3. After sixteen days repeat these observa- 

 tions on the urine in flasks B and .C. Kecord 

 the results obtained from all three flasks in the 

 table on page 203. 



.The table shows that the hydrolysis of urea 

 into ammonium carbonate still takes place in 

 urine containing enough carbolic acid to destroy 

 the micro-organisms long known to be the cause 

 of the ammoniacal fermentation. 1 It is therefore 

 probably due to a ferment, which escapes from 

 the cells after their death. 



1 Hoppe-Seyler : Medicinisch-chemische Untersuchungen, 

 Berlin, 1866, p. 570. 



