When ships needed repairing they were often hauled up a slipway to get them onto dry land. This building housed the engine and winch mechanism to pull boats out of the Humber. The Slipway now is part duckpond and part reed bed. I showed you the engine in a previous post here. There are plans to do up this building and reinstall the engine. For those interested in Victorian Docks and stuff like that there's a trail signposted running around the old Victoria Dock that starts at this very spot.