ELISHA MITCHELL SCIENTIFIC SOCIETY. 69 



ON THE PRACTICAL QUANTFrATIVE DETERMI- 

 NATION OF SUGAR IN URINE. 



JAS. LEWIS HOWE. 



The following paper makes no pretence to originality, but merely 

 aims to set forth practical results obtained by the writer in his work, 

 and give a description of that method which experience seems to show 

 the best for a physician's use. 



Most physicians of ordinary ability are limited to a few simple 

 qualitative tests for the presence of sugar in urine. The best are : 



1st. Boiling the urine with strong caustic potash — a dark yellow 

 or red color indicating sugar, the intensity of color being a very 

 rough index of the quantity of sugar present. The addition of 

 nitric acid to the solution causes the odor of caramel. 



2nd. Adding to the solution, rendered alkaline by caustic potash 

 or soda, a pinch of subnitrate of bismuth, which will turn black on 

 boiling the solution if sugar be present. 

 3rd. Fehling's test. 



It is often, however, of great advantage in diabetes mellitus to 

 know with some degree of accuracy the quantity of sugar secreted, 

 and to watch its daily fluctuations under treatment, and this few 

 physicians, unless near a city laboratory, are able to do. At least 

 one drug firm puts up compressed tablets of the ingredients of Feh- 

 ling's solution, but these are unfortunately not to be depended on 

 as recently a case came to my notice in which these tablets failed 

 to show any indication of sugar, though the secretion amounted to 

 half a pound daily. 



The following method presents the advantage of simplicity and 

 expedition, the only apparatus required being a graduated glass, 

 a burette, a porcelain dish two and a half to three inches in diam- 

 eter, a glass rod and a spirit lamp. 



The terms given are those of the metric system, since burettes 

 are usually so graduated, but the results may be easily reduced to 

 the English measure. 



Fehling's solution as modified according to Liebreich : 

 3.46 grams copper sulphate crystals (which may be weighed by 

 the druggist) are dissolved in a small quantity of water, about 

 five cubic centimeters of pure glycerine added, sixty cubic cen- 

 timeters of a solution of caustic potash of specific gravity 1.14, 



