I9i/] 



DEXX I —PERMEA BILI T 1 ' 



389 



' 



osmotic pressure and rates from the data in table X is given in 



table XI. 



Ratio of 



pressures 

 2765:13-82 



2 .OOO 

 2 .000 

 2 .000 



2 .OOO 



Ratio of rates 



I.969 

 2.020 

 1 .980 

 I.949 



TABLE XI 



Ratio of 



pressures 



41.48:27.45 



I.500 

 I.500 

 I.500 

 1.500 



Ratio of rates 



I -S30 

 I.504 



1. 471 

 1. 412 



Ratio of 



pressures 



41.48:13.84 



3.000 

 3.000 

 3.000 

 3.000 



Ratio oi ratct 



3.040 

 3.029 

 2.977 



TABLE XII 



1 





Relation between osmotic pressure 



AND RATE (CAXE SUGAR SOLUTION) 



I 

 2 



3 

 4 



5 

 6 



7 

 8 



9 

 10 



11 



12 



13 



14 



16 



n 

 18 



J 9 



Xumber 



Water (in mg.) passing through membrane in atmospheres of osmotic pressure 



5 15 



10.30 



1562 



21.25 



29.22 



48.00 



9.70 



8.55 

 8.16 



7.70 



14.09 



14-73 

 II. 81 



12.83 



IO.84 



13.69 



5-53 

 6.84 



11.98 



23-39 

 29.44 



21 . 11 



18.25 



16.83 



13-35 

 27.04 



25-84 

 19.40 



23 -45 

 21. 11 



24-53 

 9.69 



11.72 



23.96 



23.10 





29.44 



3765 

 27.09 



24-53 

 24- 25 



18.17 



36.62 



3526 



23.96 



31.66 



2795 



3i 95 

 11 .98 



13.69 



29.66 



28.07 



33-66 



35-37 



3i 95 



28.43 

 21 .96 



45.i8 

 42.79 



28.24 



35-37 

 33 66 



39 36 

 13.69 



16.54 



36.97 

 34.80 



* ■■ 



4107 



50 49 



4 75 



53 OS 



63 -32 

 84.72 



A comparison of the ratios of pressure and the ratios of the 

 rates indicated in table XII is given in table XIII. 



When the ratios of pressure applied were 2.000, 1.515. 1 36°> 

 and 1.642, the average ratio of rates observed was 1 .888, 1297, 

 1. an, and 1.285 respectively. It will be seen that the rate of 

 water penetration is nearly proportional to the pull applied when 

 sodium chloride is used, but that when cane sugar is used as the 

 external solution, the rate is not proportional to the pull, but the 



