CLARK : MOLECULAR WEIGHT DETERMINATIONS. 



253 



TABLE G.— WATER. 



Barometric variation, .50 mm. 

 Variation of room temperature, 2.1°, 



TABLE H.— CANE SUGAR. 



It was found by trial that the volume of a sugar-water solu- 

 tion varies uniformly with concentration, up to an increase of 

 42.3 per cent, for a concentration of 14 g. of sugar in 20 c.c. of 

 water (700 g. per liter ; see table H) . In the case of urea, 5.4 

 g. in 20 c.c. causes an increase of 19.6 per cent, in the volume. 



Column 5, tables A and B, is obtained from column 4 by 

 subtracting from each elevation the elevation due to increase of 

 volume as ascertained from curve 2 and from a straight-line 

 curve showing the increase of volume with concentration, which 

 is obtained from data in the preceding paragraph. 



The question of the effect of variation of length, shape and 

 size of the tube, and of the nature of the liquid used, upon the 

 elevation of temperature with increase in amount of liquid, is 

 one that the author expects to take up in the near future. 

 Only one tube has been available as yet, and only one solvent has 

 been used. 



2-Bull. No. 8. 



