A roll film negative. On board the submarine Sealion (1959) towards the end of a long refit at Portsmouth. She is berthed afloat alongside a jetty in the dockyard. The photographer is standing on top of the bridge fin looking forward and down into the navigating bridge. The portable compass is mounted on the front of the bridge. A loudspeaker is mounted on either side of the bridge and a speaking tube is on the left.