An aperture provided at the rearAlternative term for Approach To. of certain lamps, usually on Semaphore
Signals or Ground Position Light Signals to enable the SignallerA person responsible for the operation of the Signalling System, to safely control the passage and regulation of trains, usually located in a Signal Box. to see that
the SignalA visual display device which conveys instructions or provides prior warning of instructions regarding the driver’s authority to proceed. is On and LitThe internal illumination of signalling equipment..