( 'S) 



the ziiic ciecirodc l)v dilTiisioii. Ilic K. M. F. ol' llic sysicii) is dimi- 

 nished c'onsiderahlv. 



Fi.KMiMi foi- iiislaiicc stales, 'M lie sniallesl deposit of (•0]»])er ii|»oji 

 tlie ziiie, due to diiriisioji of tlie eoppei'salt into tlie zinc is indicated 

 by a niai-ked depression aiiioiintinu- to 2 or .'] percejit"", w luist Wri(;hï 

 (after ju-olonüed ditfusion) noticed depi'essions np to 6 [>ei'cent. 



Aftei- a few preliuiijiary experiments w luCIi ('(nivinced ns of the 

 accni-acy of these remarks \\ e constructed for tlie definitive measure- 

 ments the little ajiparalus shown in jiu-. 1. 



Fig. 1. 



