{"product_id":"british-railway-signalling-9780711008984","title":"British Railway Signalling","description":"\u003cp\u003eRailway signalling is a fascinating subject - fascinating because anyone journeying by train or watching trains from a vantage point near signals can observe the working of the signalling system. Regular travellers on mechanically-signalled lines, without any special interest in railways, soon learn that when the signal arm at the end of the platform is horizontal they may have some time to wait before the train arrives, but if the arm is inclined at 45 degrees up or down the train can be expected within a few minutes. Commuters in large cities know that signals for their train do not have arms but only coloured lights - red, yellow and green - rather like traffic lights on the road but upside down, for the red light is nearly always at the bottom.\u003c\/p\u003e\n\u003cp\u003eHardback, 136 pages, black \u0026amp; white photographs, drawings\u003c\/p\u003e\n\u003cp\u003eCondition: Good\/Very Good with past owner's sticker IFC\u003c\/p\u003e","brand":"Ian Allan","offers":[{"title":"Secondhand (282)","offer_id":30357312405613,"sku":"9780711008984","price":10.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1910\/7111\/files\/9780711008984.jpg?v=1703849947","url":"https:\/\/rail-books.co.uk\/products\/british-railway-signalling-9780711008984","provider":"Rail Books","version":"1.0","type":"link"}