MR. S. W. .1. SMITH (>N TIIK N.\H I.I. "!' ELECTROCAriLLARY l'HKN 'MKNA. 81 



ami 



HgCl^KCl 



Hg 



Hg 





HgCl -^ KC1 ~ KCIHgCl 



10 



;i!nl liinl them to !>< TT. and TT, respectively. Then 



aii'l 



""'.I 



where v- and 7r M are the potential (lill'rivnces between the inu'(jially-concentrated 

 solutions of KC1. C'jilculating the values of these by NERNST'S formula we get 



TT,, = '0003 and ir n = '0007. 

 The observed KM.F.s of the cells were 



TTj = -01G2 and ir l = '035U, 

 t'n mi which \vr str that (assuming NERNST'S fonnula) 



and 



7r, (w v ni = -0366. 

 Now, from the curves 



v >m - IT,,. = '0331 ( -0006) 

 and 



v^ - IT,, = -0670 ( -OOOG). 



1 1 1 'iice, subtracting corresponding equations, 



K. - J - K- - ^-J = ' 166 



and 



whereas, if the surface tension variation had been due to a purely electrostatic effect,* 

 wi- should have expected 



and 



Disagreements of a similar kind are found when solutions of other strengths are 

 examined. The same result can be very easily illustrated by means of the apparatus 



* It can also lie shown from the above and similar experiments that the surface tension variation in the 

 descending branch ran not, in general, be a purely amalgam effect. 

 VOL. CXCIII. A. M 



