A roll film negative. On board the submarine Sealion (1959) towards the end of a long refit at Portsmouth. The photographer is in the gyro compass room between 65 and 68 stations below the main flat, looking towards the aft bulkhead and down showing the lower part of the compass retransmission unit above a noise generator unit.. On the left is the side of an inverter heater unit and a pedestal desk. On the right is a cupboard unit with an ashtray mounted on it. A vertical format negative.