68 



THE DIFFUSION OF GASES THROUGH 



same as that of water. The solution may therefore be regarded as holding 

 20.8 grams of KC1 in ioo grams of water, or 17.2 grains of salt in 100 grams 

 of solution. To obtain the vapor pressure w' of the moist air above the 

 solution, it was at first assumed that the reduction of vapor pressure at 18 

 was relatively the same as at o° C. for a given strength of solution. Further- 

 more, that the case of KC1 would be practically identical with the case of 

 brine. Afterwards (using Landolt and Boernstein's tables) it was found 

 that such an assumption is inadmissible and that the equation should be 



Table 24. — Air-air through KC1 solution (20.8 grams in 100 grams water). Vessel 

 B (single tube). J/^37.425 grams; C= 134.43; p,7 = 2.47o; float, 2r = 3.8 cm.; 

 vessel, 2r=5.8 cm. p w = 1.1 133 at 24. 5 . 



Date. 



Barom- 

 eter. 



t 



" 



v 



Date. 



Barom- 

 eter. 



/ 



// 



t'o 



Sept. 18.. 



76.06 





 19.8 



67.32 



15.223 



Oct. 7.. 



75-68 





 19.2 



64.78 



14.675 



19. . 



7585 



21 .2 



66.54 



14.981 



8. . 



76.34 



19.6 



64 



<)<) 



'4 



638 



20. . 



76.03 



22.0 



66.26 



.4.878 



9. . 



76.78 



21.5 



65 



04 



•4 



631 



21 . . 



76.90 



18.8 



6533 



14.820 



10. . 



76.27 



23.0 



05 



37 



'4 



637 



23. . 



76. 8r 



17.0 



64.67 



14.752 



11.. 



76.72 



21 .9 



65 



"7 



14 



640 



24. . 



77.00 



'7-4 



64.62 



14.718 



12. . 



76.40 



22.9 



(>5 



33 



14 



633 



25. . 



76.72 



17.8 



64.74 



'4-731 



14. . 



76.88 



22.6 



65 



23 



'4 



622 



26.. 



76.54 



17.8 



64.70 



14.722 



15. . 



76.08 



22.5 



65 



1 1 



»4 



600 



27.. 



76.31 



17.8 



64.62 



14.703 



16.. 



76.92 



19.8 



64 



43 



14 



570 



28. . 



77.04 



19.2 



64.95 



<4-7'3 



17. . 



76.44 



20.4 



4 



4" 



14 



556 



30. . 



76.90 



17-4 



64.94 



«4-793 



18. . 



76.38 



21 .6 



64 



74 



'4 



559 



Oct. 1.. 



76.03 



18.0 



64-53 



14.674 



19. . 



75-97 



22.0 



64 



»4 



14 



561 



2.. 



76.58 



18.2 



64.65 



14.690 



21 . . 



77.29 



21 .2 



64 



>8 



14 



494 



3-- 



76.33 



20.2 



65.02 



14.684 



22. . 



77.08 



2! . I 



64 



36 



14 



495 



4-. 



76. 10 



22.7 



65.50 



14.691 



23.. 



76.05 



22-4 



64 



so 



U 



486 



5-. 



76.69 



20.8 



65.20 



14.699 













hept.1% 23 fflGefS 



Fig. 22. — Chart showing loss of standard volumes 

 of gas in diver in lapse of days. Diffusion 

 of air through KC1 solution. 



7r' = 7r(i —0.086) for KC1. Hence these data for KC1 in the table must be 

 corrected before the diffusion coefficients are computed, as follows : The 

 error of w' being 57r' = o.o2Q7r, its effect on v a will be 



dvo ,_ 8tt' 



This correction is to be supplied in the summary. For brine, by graphic 

 interpolation, using either Dieterici's or Smits's observations, the correction 

 is 7r' = 7r (1— 0.1 15), and this is provisionally used in table 24 and fig. 22. 



