Records of Humber Conservancy and the Humber Ports (Records deposited by Associated British Ports and its Predecessors) > Humber Conservancy > Humber Charts: Surveys conducted by the Humber Conservancy Board (including cross sections and sounding sheets) > Humber Conservancy Board: Bull Sand and Burcom Schoal Sounding Sheets > Humber Conservancy Board: Survey of Bull Sand, Grimsby Entrance, and Burcum Shoal