122 



OSMOTIC PRESSURE OF AQUEOUS SOLUTIONS. 



The loss in rotation was ascertained to be very much larger than had 

 been anticipated. For the time being, however, it was all ascribed to 

 inversion, notwithstanding certain suspicions which will be discussed 

 a little later. Accordingly, in a paper which was published soon after 

 the completion of Series II, corrections for inversion were applied to 

 the observed pressures, which were proportional and equivalent to the 

 losses in rotation. 



The uncorrected pressures of this series are given in Table 14: 



Table 14. — Cane Sugar, Series II. Extreme temperatures of the bath; loss in 

 rotation; observed osmotic pressures; calculated gas pressures. 



No attempt was made in Series II to keep the bath at a particular 

 temperature throughout. It was endeavored simply to maintain it 

 through each experiment at whatever temperature the solution was 

 found to have when the cell was filled and closed— both solution and 

 cell having stood for some time previously in the bath. 



That the fluctuations in Series II were much smaller than in Series I 

 will be seen in Table 15. 



The most surprising, and at the same time the most perplexing, 

 feature of the results was the large loss in rotation. It amounted, as 

 will be seen by Table 14, to a total of 38.4°, which was equivalent 

 to about 9.37 atmospheres of osmotic pressure. Expressed in another 

 way, the total loss in rotation amounted to 2.86 per cent of the sum 

 of all the original rotations of the solutions whose pressure had been 



