The file consists of correspondence between the Engineer to the Humber Conservancy Board (Arthur Ernest Butterfield) and the Principal Examiner of Masters and Mates for the Board of Trade. The subject matter is the positions of wrecks, lost anchors, and cables within the Board's jurisdiction (i.e. the Humber and the Rivers Ouse and Trent). This includes correspondence connected with the wreck 'Hadrian' and various sunken dredgers.

Also included in the file is correspondence concerning lights and fog horns used by the Board. This includes correspondence with the Palatine Engineering Company Limited regarding a Sounding Fog Horn Bell (a drawing of the striking mechanism is also included), and correspondence with Pintsch’s Patent Lighting Company Limited (London) on the subject of flashing lights.