Signalmen used to be responsible for changing points and setting signals to ensure railway safety, working in a signal box. q=signal+box&hl=en&rlz=1C1CHNU_enGB339&prmd=imvns&tbm=isch&tbo=u&source=univ&sa=X&ei=yLHWTo2vGoLX8QPzrpT3AQ&ved=0CG8QsAQ&biw=1280&bih=685 for pictures (Ah! ) Rover
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