A roll film negative. On board the submarine Sealion (1959) towards the end of a long refit at Portsmouth. The photographer is in the aft auxiliary machinery and gland space (thrust block compartment) between 103 and 107 stations below the main flat. He is looking to starboard showing the starboard propeller shaft with the brake on the left. The shaft is straddled by a table holding a Wolf grinder. On the right is a Johnson lathe. Against the side of the boat is a large air bottle. A vertical format negative.