The negative electrode is composed of an amalgamated zinc plate held by a brass rod which, being able to slide up and down through the hard rubber lid, allows the electrode to be lowered into the liquid when the pile is to be used and raised out of the liquid when not in use.
The screw that holds the rod in position is connected, by means of a small strip of copper, to one of two clamping screws attached vertically to the lid. The amalgam protects the zinc electrode from corrosion by the sulphuric acid when the circuit to which the pile is connected is open.
The positive electrode is composed of two plates of retort graphite partially immersed in the liquid, parallel and quite close to the zinc plate, one on one side and one on the other. They are connected to each other and to the other clamp by means of a metal ring attached to the inner side of the hard rubber lid. ...continues