Vol. VI, No. 2.J 



[N.S.] 



i Nickel 55 



In experiment 1 a flat earthern-ware pot (such as those 

 used in ordinary Grove cells) was used, for the rest the 

 specially devised filter paper partition was used. 



Concluding Remarks. 



The device adopted in the last series of experiments may 

 probably be used with advantage in nickel-plating on a com- 

 mercial scale both for the saving of current from useless waste 

 in gaseous decompositions and also for the good adherent 

 deposits which it ensures. 



An experimental determination of the electro-chemical 



equivalent of cobalt and iron on these lines might be found 

 useful. 



The atomic weights of nickel and cobalt as determined by 

 chemical methods, is at present only known with an uncer- 

 tainty of about two per cent. A careful determination of the 

 e.c.e. of nickel and cobalt according to the method suggested 

 by these researches has, it may be presumed, its special advan- 

 tages for examining the atomic weights of these metals and 

 will evidently furnish quite an independent method of verifying 

 results obtained bv purelv chemical processes. With the solu- 



© 



has 



pay- 



ing any attention to its chemical purity other than that which 



may be looked for from repeated crystallizations, I find that 



the e.c.e. of nickel (taken that of silver as -001118) is 



0003036 + 0000003 (probable error), which leads to a value 



of the atomic weight of nickel as 58*52+ 06. 



A repetition of Hittorf 's experiments on the effect of tem- 

 perature of the electrolyte upon its deposits performed with 

 the precautions for eliminating spurious effects due to acid, as 

 adopted in these investigations, would be an interesting experi- 

 mental study. 



easure 



M 



Educational Service, for many encouraging suggestions and help 

 duri \g the progress of the work. 



