and the froth dissipated. The density was then taken a 

 second time, and the loss calculated. 



Operating in this way on a specimen of diabetic urine 

 sp. gr. 1038*60, the following results were obtained ; — 



Sugar, per 100 parts, by the volumetrical method, 7*69. 



Density before fermentation at 60° or D = 1038*60. 



Density after fermentation at 60° or D' = 1005*92. 



Density lost, or D — D^ = 32*68. 



The relation, therefore, between the density lost and the 

 percentage of sugar, in this instance, was as 32*68 to 7*69, or 

 as 1 to 0*235. By numerous trials with diabetic urines, of 

 diiferent strength, it was found that the most correct pro- 

 portion was as 1 to 0*230. The corresponding formula, 

 therefore, was : — 



Sugar, per 100 parts, or S == (D — DO X 0*23. 



The accuracy of this method was further tested by operating 

 on diabetic urine diluted with known volumes of water or 

 non-saccharine urine, and on solutions of loaf sugar in water 

 and in healthy urine. 



This method of estimating sugar is especially applicable 

 to medical practice, and the following simple and most con- 

 venient rule expresses the result of the analysis: — 



Each degree of ' density lost ' indicates one grain of 

 sugar per fluid ounce of urine. 



PHYSICAL AND MATHEMATICAL SECTION. 



October 11th, 1360. 



Some conversation took place respecting recent storms, 

 and the bearing of the new weather tables, given in the 

 Tines, on their theory, as Mr. Baxendell remarked that 



