A piece of machinery in the submarine base at HMS Dolphin, Gosport, Hampshire.

Looking down into a cylindrical object that is part of a large piece of machinery photographed in the submarine base HMS Dolphin at Fort Blockhouse, Gosport. A circular end plate has been removed to reveal the four shafts of the machine which can be seen in other negatives in this series. Loose nuts and bolts and a hand-held pump action oil can are in the bottom of this cylinder. The Portsmouth Dockyard negative register refers to this equipment as a "mechanical device". This is the same device as is shown in pieces in negatives numbers N26663 to N26671.