6i 



ounces (60 cc.) of urine with a quarter of a cake of com- 

 pressed yeast in a bottle. Set aside for twenty-four hours 

 in a moderatel3' warm place. After the fermentation, take 

 the specific gravity again and subtract from that taken be- 

 fore. Each degree of the remainder represents one grain of 

 glucose to the fluid ounce. Multiply b}' 0.219 to get the 

 percentage. Thus. Specific gravity before fermentation, 

 1035. Specific gravity after fermentation, 1015. 1035 — 1015 

 equals 20 degrees of density lo.st, or 20 grains of .sugar to 

 the fluid ounce. This test is conclusive as to the presence 

 of sugar, though it is not absolutely accurate as to quantity. 



279. Einhorn's Fermentation Saccliarometer. Determine 

 the specific gravity of the urine, which is diluted according 

 to the specific gravity as follows : 



Specific gravity, 1018 — 1022, dilute it with 2 volumes of water. 

 " " 1022 — 1028, " " " s " " " 



" " 1028 — 1038, " " "10 " " " 



Take one gram of compressed yeast. Shake it thoroughly 

 in the test-tube with 10 cc. of the urine to be examined. 

 Pour the mixture into the bulb of the saccharometer and by 

 inclining the apparatus the fluid will displace the air in the 

 cylinder and remain there by atmo.spheric pres.sure. Be sure 

 that no air bubbles remain in the cylinder. It is always well 

 to test a normal urine at the same time and in the same way 

 as a control. The apparatus should remain in a moderately 

 warm place for 24 hours. If the urine contains .sugar, it is 

 broken up by the fermentation into COj and alcohol. The 

 COj gathers at the top of the cylinder, forcing the fluid 

 back into the bulb. The changed level of the fluid in the 

 cylinder shows that the reaction has taken place and indi- 

 cates by the numbers the approximate quantity of sugar 

 present. The scale on the tube is empirical and indicates 

 directly the percentage of sugar in the urine. 



280. Bile in urine. The biliary constituents appear in 

 the urine in cases of jaundice and in poisoning with phos- 

 phorus. 



