A roll film negative. On board the submarine Sealion (1959) towards the end of a long refit at Portsmouth. The photographer is in the air conditioning compartment below the main flat between 68 and 73 stations, looking forward along the passage from 74 station showing an automatic emergency lantern in the left foreground with a main vent fan and two cabinets fitted with combination locks beyond it. The door into the cool room is on the right. A two-drawer filing cabinet is on the deck. A vertical format negative.