CANE SUGAR. 



139 



Series VI.* 



The conditions under which the measurements of Series VI were made 

 were essentially the same as in Series V. Some improvements had been 

 made in the interval between the two in both the cooling and heating 

 systems, and the circulation of the bath water surrounding the lower 

 half of the cooling system had been made more effective. Some slight 

 improvements had also been made in the manipulation. The beneficial 

 effect of the alterations is shown in the smaller fluctuations of bath tem- 

 perature and in the diminished loss in rotation. Except in one case, 

 the dilution was confined to the solutions of higher concentration. 



Table 29. — Cane sugar, Series VI. Bath temperatures; losses in rotation; observed osmotic 

 pressures; and calculated gas pressures of the solute. 



Table 29 gives the temperatures, the losses in rotation, the observed 

 osmotic pressures of the solutions, and the calculated gas pressures of 

 the solute. 



In Series VI, the sum of all the original rotations was 1249.59°. A loss 

 of 1.35° amounts to 0.11 per cent, or a dilution equivalent to 0.34 atmos- 

 phere for the whole series. The corresponding values for Series V were 

 1249.60°, 2.50°, 0.20 per cent, and 0.64 atmosphere. The sum of all 

 the fluctuations in bath temperature was 0.4° in Series VI, and 1.4° in 

 Series V. There were no upward displacements of the manometer. 



In Table 30 the observed pressures are corrected for the small losses 

 in rotation. 



♦Measurements by H. N. Morse and B. Mears. Am. Chem. Jour., xl, 194. 



