10-GranthamYardBox+bobby Signalman Jock Drummond is at the window of the Yard Box on 5th September 1963, a fine autumn day. From within you moght hear the block bells ring, announcing the approach of another train on the main line. What will it be? If you've learned the block signalling bell code you may be able to work it out! Photograph by Cedric A. Clayson, © John Clayson.