In order to facilitate the description of the placing of the wires by means of which communication is to be established between the electrodes and the binding posts, I shall term the end of the wire that is to be attached to the electrodes the distal, that which is attached to the binding posts the proximal end. A gimlet hole sufficiently large to admit of the passage of one wire should be made half an inch outwards from the centre of the site of each binding post. The best wire to use is about No. 16 copper wire, coated with gutta percha or rubber. The site of the posts being as above suggested, it will be found that the wire which is to connect the head electrode with one post requires to be about 18 inches long, that which runs from the other post to the foot-electrode, between eight and nine feet. The distal ends of the wires should be stripped of their coating for a length of about three inches, the proximal ends for about two inches. The denuded portion of the distal ends should be rolled up in the form of a spiral coil; this will insure their constant impinging on the carbons more certainly than could be expected from a simple straight end of wire. The carbons having now been fitted in their beds, the distal end (coil) of the head wire is placed beneath the carbon, and the wire itself continued up along the vertical groove to either one of the gimlet holes. Through this, from within outward, the proximal end of the wire is now drawn and left for the present. The distal end of the second wire having now been placed beneath the carbon at the foot of the tub, this wire is continued up through the vertical groove, along the upper edge of the foot of the tub to the side nearest the binding post to which the wire is to be attached, along the groove on the upper edge of this side to the head of the tub, and thence to the respective gimlet hole, and through this, from within outward. The wires being now all in position, all the coping is next screwed or nailed down firmly, care being taken that the screws or nails used for this purpose do not injure any of the wires. The coping fastened down, the binding posts are now screwed down in the sites previously marked out for them. Before they are screwed _entirely_ down, the denuded portion of the proximal end of each wire is securely wound around the screw of the respective binding post, and the posts are then _firmly_ screwed down, holding the proximal ends of the wires in place. Connection is now established between the binding posts and the head and foot electrodes respectively. The vertical grooves are now to be filled in with putty and painted over, care being taken to keep the carbon free from paint. The last step towards completing the apparatus is to fasten the carbons in their beds. The simplest way of doing this is by stretching over each carbon a piece of muslin, folded double, and tacking this down around the edges. Zinc or galvanized iron tacks are best.