1888.] Development of Electricity by Atmospheric Oxidation. 193 



E.M.F. of Cells set up with Electro-copper aod Ammoniacal 

 Solutions, sNHg^NH^UOOHjjO. 





y = (pure ammonia). 



JF = 0-8. 



y = 5. 



x =1-25. 



a? = 2-0. 



x = 2-6. 



\x = 2 -6. 



x = 



2-6. 



x = 12. 



Spongy platinum. 



0-440 



0-460 



0-470 



0-552 







•579 





Spongy gold 



0-410 



0-450 



0-460 



0-492 







•522 





Spongy silver 



395 



0-410 



0-420 









471 



















470 



0-570 



Palladium foil . . . 















450 



0-560 



Platinum foil . . 



0-3*95 



0-405 



0-410 



437 







•450 



0-520 





0-330 



0-340 



355 



0-404 



o 



445 



0'510 



Gold foil 











•0 



•403 





Silver 















•403 





With brine saturated with ammonia and spongy platinum aeration 

 plates higher values still were obtained, reaching up to about Ovo as 

 a maximum ; but, owing to evaporation of ammonia, these high 

 values rapidly diminished on standing a short time. 



Cells set up with Amalgamated Zinc and Bright Silver Foil as Oxidisable 



Metals, 



The following numbers were obtained as the average values for 

 cells of this kind : — ■ 



Values of K 3 = effect of substituting other Metals for Copper in 

 ajNH 3 ,yNH 4 Cl,100H 3 O. 

 x = 2-6. 





y = (pure ammonia). 



y = 0-8. 



y = 5. 





+ 0-960 

 -0-385 



+ 0-930 

 -0 340 



+ 0-920 

 -0-340 



