of Water from Salt-Solutions. 

 Table V. (continued) . 



509 





P~ 



~P' for 

 n 



n KN0 3 100 H 2 0. 





n. 



70°. 



75°. 



80°. 



85°. 



90°. 



95°. 



1. 



3-90 



5-20 



6-80 



7-80 



940 



11-10 



2. 



375 



4-85 



6-10 



7-50 



910 



1060 



3. 



333 



4-20 



5-23 



6-57 



8-00 



9-77 



4. 



3-35 



4-18 



5-20 



6-50 



7-93 



9-75 



5. 



3-16 



4-04 



5-00 



6-16 



7-58 



9-30 



10. 



2-73 



3-46 



4-30 



5-37 



6-62 



813 



15. 



243 



3-08 



3-86 



479 



5-91 



7-25 



20. 



2-25 



2-84 



357 



442 



547 



6-71 



25. 



205 



2-63 



3-30 



4-08 



501 



616 



The accuracy of the above results is undoubted, though it 

 is at variance with the results obtained by Wiillner (Joe. ctt.), 

 who found that the effect of the above salts was in direct pro- 

 portion to the quantity present; nor can the conclusions of 

 Wiillner be explained by the fact that his solutions were of 

 percentage composition, while the above are molecular, corre- 

 sponding to parts per hundred of water ; for though this 

 might explain one class of salts, it fails if applied to the 

 others. My results, on the contrary, are confirmed by those 

 of Tammann "*, obtained by the barometer-tube method, as will 

 be shown later. I reserve the discussion of the probable 

 cause of this different behaviour of the salts to the end of the 

 paper. 



The behaviour of the salt-solutions of the same strength, 

 but at different temperatures, has now to be examined, a 

 point which is by no means so simple as the preceding. Per- 

 haps the best method is a comparison of the values of the 



fraction - — — or 1— — , in which the variation in vapour- 



pressure is eliminated. The values of \±- — ^--x 10,000 I are 



given in Tables VI., VII., and VIII. for NaCI, NaN0 3 , and 

 KN0 3 ; that for KC1 being practically a constant for each 

 solution and independent of the temperature. 



*= 2^^x 10,000^ = 172 + 5. 



= 4 =181 + 2. 



= 6 =185 + 2. 



= 8 =189 + 2. 



= 10 =193±1. 



* Wiedemann's Ann, xxiv. 



KOI. 



