Specific Rotation. 
1914-15.] 
The Optical Eotation of Sugars. 
31 
a-C?-GLUCOSE. 
Glucose (Kahlbaum) was recrystallised three times from 90 per cent, alcohol 
solution. It was powdered and then dried at 105° till of constant weight. 
Extremely accurate cryoscopic measurements of glucose in water having 
been made by several investigators (Loomis, Zeitsch. physikal. Chem., 1901, 
xxxvii, 407), it was not considered necessary to repeat them. The data 
obtained in formamide solution were : — 
