1877.] Dr. E. J. Mills on Electro striction. 507 



y= 10-826 (-96179)* + 1-535 (-82044)*. 

 Table III. 









Temp. 



1 



11-670 



11-671 



o 



19-1 



2 



11-010 



11-047 



19-7 



o 

 O 



10-517 



1 A. A ^70 



iu 4/y 





4 



10-062 



9-959 



20-6 



5 



9-400 



9-480 



20-7 



23 



4-358 



4-435 



15-1 



24 



4-250 



4-263 



15-7 



25* 



4-193 



4-099 



16-3 







Mean temperature 



18-4 



The probable error of a single comparison is -047. 



Iron. — The bulb of thermometer 455 was prepared as usual, and then 

 coated during two hours with copper. Electro -deposition of iron was 

 next proceeded with, and the following results recorded. Between the 

 third and fourth hours a slit was seen to form at the bottom of the bulb, 

 and gradually extend to the shoulder. 



Table IV. 



Hours. Total ascent. Temp. 



1 0-883 17-5 



2 1-775 17-3 



3 2-193 17-4 



4 1-648 17-6 



It must be extremely difficult to obtain a coating of iron of any con- 

 siderable thickness. 



Nickel. — Thermometer 454 was used. The anode and kathode were 

 95 millimetres apart. The electrolyte consisted of a neutral solution of 

 ammonio-nickelous sulphate ; the anode of nickelous carbide. 





Table V. 





Hours. 



Total ascent. 



Temp. 



2 



0-096 



18-6 



3 



0-474 



19-2 



4 



0-759 



19-8 



5 



0-856 



20-6 



6 



2-314 



19-8 



24 







When last observed the deposit had split outwards, beginning at the 

 side opposite the anode. 



* Mean of 24'5 and 25*5. 



