GLUCOSE. 



155 



like glucose Series I, differs strikingly from all of the eight cane-sugar 

 series, in which the ratios differed from concentration to concentration. 

 The mean ratio for the 0.1 normal solution is 1.076, while the mean ratio 

 for the whole series is 1.058. It would be premature to discuss this 

 apparent exception at the present time, but it may be noted in passing 

 that a similar increase in the osmotic pressure of very dilute solutions, 

 when near their freezing-points, has been observed in the case of cane 

 sugar. 



Table 42. — Glucose, Series II. 



The most noteworthy feature of the ratios is their high value as 

 compared with the corresponding ratios of glucose Series I. The mean 

 ratios of the two series are 0.994 and 1 .058 respectively. The difference 

 between them is about 6 per cent. The only essential difference in 

 the conditions under which the two series were carried out was that 

 of temperature, Series I having been done at approximately 25° and 

 Series II at approximately 0°. The decrease in ratio with rise in 

 temperature suggests a hydration of the solute at lower temperatures, 

 which diminishes or disappears when the temperature is raised. But 

 this matter can be discussed more advantageously when more facts 

 concerning glucose have been established, and in connection with similar 

 conduct on the part of cane-sugar solutions. 



