'H41' in block letters appears in pencil, top right, and on the right of the sheet is a port-quarter view of a submarine, presumably either heading into or out of harbour, followed by a naval launch rowed by four men, with a coxswain steering. It is, as the inscription suggests, a reasonable depiction of the submarine H41,which was launched on 26 July 1918 but sunk in collision at Blyth on 18 October 1919. The depot ship 'Vulcan' was undergoing basin trials with submarines berthed alongside her when 'H41' was sucked into her port quarter, holed by her port propeller and sank. She was refloated on 18 November 1919 but was not considered worth repairing and was sold for breaking in March 1920. On the left of the sheet is a sketch of two paddle tugs, one in stern view with a barge or small hulk to starboard, and one in bow view beyond. This appears to be a separate drawing rather than part of the submarine study.