A roll film negative. On board the submarine Sealion (1959) towards the end of a long refit at Portsmouth. The photographer is in the forward torpedo compartment looking aft from the centreline at 30 station showing the platform providing access to the watertight hatch leading aft to the junior rates mess. The ladder leading up to the platform is in place partially obscuring the CO² absorption unit which is under the platform. On either side of the centreline are the torpedo tube reloading tracks.