To accomplish this object, carry one of the wires from the magnet M to the distant station. Here let the wire be passed through the coils of a bell-magnet or other signaling device, and thence be carried to the track and attached to the same, as already described. The office signal will operate simultaneously with the signal S. Thus any desired number of signals may be operated simultaneously, at different points, from a single section of track. By a slight modification of the plan described an efficient switch and drawbridge signal may be operated, the rails being used as conductors. Thus half a mile, more or less, from a switch may be placed a signal-box and signal, substantially as described, and connected with the rails, as shown. Near this point let the rails be divided, taking care that the signal and battery wire are connected to the section toward the switch. Now, while the switch is on the main line, the bars connecting the rails of the switch will act as a bridge to divert the electricity from the signal-magnet. But when the switch is misplaced the metallic connection of the rails of the track will be interrupted. The signal-magnet will thus become charged and the position of the signal changed. In this case the signal should be exposed when the magnet M is charged. In like manner a cross-bar may bridge the rails on a draw-bridge. The displacing of the draw-bridge or withdrawing of the bolt or bolts which hold the same in position will allow the signal-magnet to become charged and the signal to be changed, substantially as described, in connection with a switch. It is not necessary in all cases that the rails _a_ and _b_, section C, should both be separated from metallic contact with the sections D and E. It may often, if not always, be sufficient to separate only one of said rails from such metallic contact with the adjacent sections. What I here claim as new, and desire to secure by Letters Patent, is-- 1. The battery B and magnet M, so connected with the rails of a section of railroad track that when said section is bridged by the wheels and axle of a car the electric circuit is changed and the signal operated through the demagnetization of the magnet M, substantially as specified. 2. A signal constructed partially of tubular material, for the purpose of securing lightness combined with strength, in the manner substantially as herein set forth. 3. The arrangement of the pivotal bearing of the lever _e_ at a point midway between the horizontal lines of exposure and concealment of the signal-disk, as shown and described, for the purpose set forth. 4. The combination of the elastic spring _i_, or its equivalent, with the levers L and _e_ and signal-disk S, substantially as set forth. 5. The battery B, in combination with the wires _k k'_, rails _a b_ of a railroad track, wires _l l'_, and magnet M, substantially as and for the purpose herein described.