The ‘dead man’s handle’ was designed to act in the event of a driver falling ill while on duty. With the introduction of electricity on the railways at the end of the 19th century the fireman was no longer needed, so the driver worked alone in the cab. The Ghostly Driver poster (1912, pictured) highlighted the alerting device, which consisted of a flat knob on top of the controller handle. This was supported by a spring weak enough to be held down without effort by the driver’s hand when operating the controller handle. As long as the driver kept the knob down, the controller operated normally. If pressure was released for any reason (ie if the driver became unwell and lifted his hand) the current was immediately cut off and the brakes were applied. The device is still used today, but is more commonly called a vigilance device.
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