130 OXIDES WITHOUT AZOTE NOT OILY. 



sugar of grapes, he obtained a compound exactly coinciding 

 with Brunner's, since it consisted of, 



Common salt, . 28 



Sugar, . 75 



100 



In some rare cases of diabetes, the quantity of common salt in 

 the urine is so great, that, by evaporating it by a gentle heat, 

 crystals are deposited consisting of common salt combined with 

 diabetes sugar. 



Sugar of diabetes was first analyzed by Dr Prout.* He found 

 it composed of 



Carbon, 36- to 40- 

 Hydrogen, 7*11 to 6-66 

 Oxygen, 56*89 to 53-34 



100-00 100-00 



But these differences are too great to enable us to deduce the 

 constitution of diabetes sugar from the analysis. Peligotf ana- 

 lyzed diabetes sugar with great care in 1838, and found its con- 

 stituents to be 



Carbon, . 35'88 



Hydrogen, . 7-44 



Oxygen, . 56-68 



100-00 

 This gives the formula, 



12 atoms carbon, . = 9*00 or per cent 36-36 

 14 atoms hydrogen, =1-75 ... 7-07 



14 atoms oxygen, = 14-00 ... 56*57 



24.75 100.00 



This is obviously the same constitution which sugar of grapes 

 has. By heat diabetes sugar may be deprived of two atoms of 

 water, and thus it becomes, 



Phil. Trans. 1827, p. 373. f Ann. de Chim. et de. Phys. kvii. 142. 



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