212 
Proceedings of the Royal Society of Edinburgh. [Sess. 
Maltose. 
Considerable difficulty was found in the purification of samples of 
maltose commercially obtainable. We are indebted to Mr John Ford, F.I.C., 
for a sample which, after recrystallisation from alcohol, was perfectly 
colourless, and on heating melted between 125° and 130°. 
The cryoscopic measurements in water and formamide solutions gave 
the following values : — 
1 
Solvent. 
Concentration per 
100 grams solvent. 
Mol. weight 
found. 
Mol. weight 
calculated. 
Water 
0-45 
341-8 
342 
55 
0*56 
3330 
55 
Formamide 
0-35 
301-6 
55 
5 ) 
0*69 
297-6 
„ 
The slow rate of solution of maltose in formamide probably accounts 
for the low values obtained. 
The polarimetric results (cf. figs. 5 and 6) were as tabulated. The 
values for pyridine solution are those of Grossmann and Block (for red 
light) and Schliephacke (Ann., 1910, 377, 164) : — 
