10 as best shown in fig2 opening 13 will be located a slight distance above the upper surface 11 of the liquid electrolyte solution opening 13 is provided with a catch or gate 14 which permits downward entry of an electrode but prevents escape of electrodes from the upper end of the anode guide means electrodes 2a may be continuously fed to the stack of electrodes by means of a fresh electrode feed means illustrated generally at 15 feed means 15 includes a hopper 16 which contains a quantity of the spherical electrodes 2a the fresh electrodes are fed from hopper 16 to opening 13 by a transport tube 17 dimensioned to permit passage of the electrodes in a straight line so that the electrodes move by gravity through the transport tube to opening 13 a plunger 18 having a lower end 19 conforming to the shape of the outer surface of the electrodes is mounted for reciprocating vertical movement in the direction of arrows 20 in the upper end of the guide means 8 when plunger 18 is pushed downwardly the entire stack of electrodes in the guide means 8 is displaced with the lowermost one of the electrodes being ejected from the bottom of the stack as will be described hereinafter thereafter when plunger 18 is moved upwardly the next electrode in transport tube 17 will fall onto the top of the stack thereby replacing the spent electrode at the bottom of the stack with a fresh electrode at the top this process may continue indefinitely as long as a supply of fresh electrodes exists furthermore plunger 20 may be operated manually or may be.