266 



Mr. F. E. Smith on Cadmium Amalaams 



which fell in 5 days to 103032 v. After 30 days this latter 

 cell had the value 1*02964 v., which is almost identical with 

 the value given for 16 c in Table VI. 



Seven cells were prepared with 12-J per cent, amalgam. 

 The first tour contained amalgams which had been chilled 

 with alcohol cooled with solid C0 2 ; the fifth was chilled by 

 immersion in a mixture of ice and salt at — 10° C. ; the 

 sixth was chilled in water at 0° C, and the seventh was 

 allowed to cool in a normal manner. The E.M.F.'s of the 

 seven cells are given in Table VII. 



Table VII. 



Giving the observed E.M.F.'s at 0° 0. of cells containing 

 12^ per cent, amalgams. 





Observed E.M.F. = 1-01840 +. 



Amalgam. 













1st day. 



5th day. 



30th day. 



Chilled to about -50° C 



0-00036 



000238 



000222 



" " " 



47 



273 



310 



„ „ „ „ 



41 



340 



360 



,, -, ., „ 



116 



83 



80 



., „ -10° 



52 



03 



17G 



„ „ 0° 



41 



45 



44 



Cooled normally 



40 



40 



41 



The E.M.F.'s of the chilled amalgam cells dealt with in 

 Tables VI. and VII. cannot be regarded as constant even 

 after 30 days. The small decline in E.M.F. from the 10th 

 to the 30th day (Table VI.) was possibly the commencement 

 of a fall which would have lasted a considerable time, and 

 may be due to the chilling producing a too highly con- 

 centrated amalgam in the outer shell. However, the 

 uniformity of the results (see fig. 1) leads us to believe that 

 the maximum values of the E.M.F's for homogeneous 

 amalgams are not very different from those observed on the 

 30th day. 



With regard to the slowly cooled amalgams (p. 265), it 

 will be seen that the low initial E.M.F. is explained if the 



