Smithsonian Report, 1 91 3,— Cottrell. 



Plate 7. 



Fig. 9.— Buss Bars and Heads of Discharge Electrodes in Parting-Room Flue 



AT Selby Smelter. 



Fig. 1 0.— Electrodes Insidl uh Pahi inl.-Ruum Flue at bELbv Smelter. 



