BRITISH RAILWAY SIGNALLING INSTRUMENTS

Walker's One Wire Two Position block

The South Eastern Railway built their own signalling instruments, designed by their engineer Herbert Walker.

This enormous but basic signalling instrument was introduced in the 1870's with the last examples still in use 100 years later.

It works on the same principle as other two-position blocks - see the Tyer & Co examples - using a single line wire to work the indicators (the miniature signal arms) and the bell (on top).

The device in the small wooden case below is a combined commutator and bell plunger.

This example was at Rye.

Walker's Train Describer

Machanical train describers were often provided to assist signalmen with their routing of trains at junctions.

The pointer on the clock-face dial is moved around by pulses of electricity sent from the adjacent box, and the white discs identify the destination of the train.

Additionally, a small bell is provided at the top, which rings in unison with the movement of the pointer, acting both as a means of alerting the signalman and allowing him to detect the destination of a train (by the number of beats) without actually looking at the instrument.

The instrument illustrated here was at Longhedge Junction.