OF SUGAR IN DIABETIC URINE. 207 



The fermentation method, on the other hand, is of ex- 

 ceedingly easy performance, and the taking of densities is 

 an operation to which the medical practitioner is daily 

 accustomed. I shall have an opportunity through another 

 channel to bring this method under the notice of my 

 medical brethren, and to enter more fully on the particu- 

 lars which concern its clinical application. I content 

 myself here with a short sketch of the process, as it may 

 be conveniently carried out in private or hospital practice. 



1. The specific gravity of the urine is taken at the 

 ordinary temperature of the ward or bed-room. 



2. Three or four ounces of the urine are poured into a 

 12 oz. phial, together with a lump of German yeast of the 

 size of a large filbert. 



3. The bottle is lightly corked, or covered with a slip of 

 glass, and set aside in a warm place to ferment. 



4. In about eighteen hours, when the fermentation has 

 entirely ceased, the bottle is tightly corked and removed 

 to the ward or bed-room so that it may cool to the tem- 

 perature at which the specific gravity was taken the day 

 before. 



5. The urine in the meantime clears, and in five or six 

 hours it may be decanted into an appropriate vessel and 

 the specific gravity taken again. 



6. The amount of "density lost" is thus ascertained, 

 and the following simple and most convenient rule ex- 

 presses the result of the analysis. 'Each degree of " density 

 lost " indicates one grain of sugar per fluid ounce of urine. 

 So that in the example already quoted in the earlier part 

 of this paper, where the urine lost 32"68° of density after 

 fermentation, the quantity of sugar indicated was 32'68 

 grains per ounce, or 653'6 grains per imperial pint. 



