REPORT OF MR. ROBERT B. LINES.
463
direct, and No. 4 to the main line from semaphore to station. Nos. 5, 6, 7 and 8 are attached to the ends of the coils of the electro-magnet f, by which the clock-work is put in operation.
The arm being at the position of " arrest,” the circuit from the line wire passes through springs 4 and 8 (their corresponding cogs being connected) to one coil of the magnet /, thence by 7 and 6 through the other coil of the magnet in the ordinary direction, thence through 5 and 3 to the ground.
If now a current is put on at the station, or comes accidentally upon the line, the clock-work is released, the wheel makes a half revolution and brings the cogs numbered from 1 to 8 opposite their respective springs. The circuit may then be traced from the battery g 1 to 2, thence to 6 and 7, where it divides, part of the current passing through the right hand coil of the magnet in the ordinary direction to 8 and out on the line, ringing the bell at the station, and the rest going in the opposite direction through the left hand coil, back to 5, thence through 1 and the resistance coil to the ground.
A simpler method of accomplishing the same object, if practicable, might be to have the commutator merely cut out one coil of the electro-magnet f when the arm is thrown up to "line clear,” and so to proportion the strength of the batteries g 1 and g , and the resistances of the magnet jf, and that employed for the "control” bell, as to permit the extra battery g 1 to sound the bell without being able to influence the magnet of the semaphore through one coil. The battery 9 coming in aid would add sufficient strength to the current to draw down the armature of the magnet f , release the clockwork and restore the semaphore to "arrest.”
The use of these or similar contrivances in systems of distance signals worked by electricity and clock-work would save the expense of two wires, and, in the Hohenegger system, of an induction apparatus. The cost and care of an extra battery at the semaphore would be added. The consequences of atmospheric electricity would not be avoided, but rendered harmless by the prompt alarm sounded at the station. Of course, when the signal is accidentally changed from "line clear” to "arrest,” no damage, but only delay,