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 and slightly forward from the main flat at 78 station. In the foreground is an oil fuel separator with the battery vent trunk between it and a Reavell H.P. air compressor. Groups of handwheel valves and a vertical row of nine connector boxes are against the forward bulkhead. A vertical format negative.