Records of Humber Conservancy and the Humber Ports (Records deposited by Associated British Ports and its Predecessors) > Dock Engineering Records > Hull Town Docks Plans > Humber Dock: Cranes and Coal Hoists > L.N.E.R. Humber Dock, Hull: Arrangement of Main Pressure & Return Stop Valves for 30 ton Fixed Hydraulic Coal Hoist