112 Messrs. Wright and Thompson on the Determination of 
rises. Thus the following numbers were obtained with solu- 
tion-strengths mZnCl, 100H,O, the probable error being 
from +:002 to +:003 in each case. 
= UO 1°123 
=1:0 1:093 
= 570) 1:0438 
= 95 "988 
From these values the following thermovoltaic constants 
result, the values of Hy being calculated from the heat-values 
112840 —82550—h=30290—h, where h is heat of dilution of 
mZnCl, 100 H,0 to 25 ZnCl, 100 H,0. 
M. h. 30290 —h. Eu. E. H— Hu. | 
25 0 30290 668 1°123 +°455 
1:0 1250 29040 640 1:093 +°453 
5:0 4800 | 25490 562 1-043 +481 
9°5 6000 24290 536 "988 +452 
Observations with cells containing electro-cadmium im- 
mersed in *25CdCl, 100 H, O opposed to mercury in contact 
with calomel suspended in zinc-chloride solution of the same 
strength led to nearly the same value for the thermovoltaic 
constant when m=*25 :— 
Maximum E.M.F. observed . . . ‘806 
Minimum m a & ee et ool 
Average Ms . Sas. aloes 
Probable error . . . . . «. +:0030 
Voltaic 
constant. H—-Ey. 
Zinc-cadmium + Cadmium-mercury... { 530 | ——slaliZe) +'461 
Zine-mercury cells........ So ieientea stone erate isin = 1128 +455 
Wieansheee 1126 4-458 
Substituting cadmium-chloride solution for zinc-chloride 
solution as the menstruum in which the calomel is suspended 
raises the value of H, as might be anticipated from various 
analogous results above described. Thus the following values 
were obtained with zinc-mercurous-chloride and cadmium- 
mercurous-chloride cells so set up, the amalgamated-zinc plates 
being surrounded by zinc-chloride, and the electro-cadmium 
plates employed with cadmium-chloride solution, the solution- 
strength being uniformly 25 MCI, 100 H,O. 
