A roll film negative. On board the submarine Sealion (1959) towards the end of a long refit at Portsmouth. The photographer is in the generator room between 77 and 92 stations looking aft and to port from the main flat at 80 station showing the instrument panel at the forward end of the port 16 cylinder Admiralty Standard Range diesel engine. Temperature gauges are fitted to each of the cylinders and a gauge showing keel depth in feet is on the left. An automatic emergency lantern is in the right foreground.