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 to starboard, slightly forward and up from the main flat at 79 station. The battery vent trunk is in the centre of the picture. Valve handwheels and a tank capacity gauge are against the forward bulkhead. The H.P. air compressor starter No. 1 box is against the starboard side of the boat on the right. A vertical format negative.