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

A dismantled part of a large piece of machinery photographed in the submarine base HMS Dolphin at Fort Blockhouse, Gosport. This appears to be the circular casing mentioned in negatives numbers N26663 and N26664 and shown complete in negative number N26665. It has four shafts attached to it, including one that has a screw thread. The circular ring has been split into two halves and it has a toothed band running through the centre of it. A small plate on the dismantled part of the cicular ring has stylized letters inscribed which appear to be RRS. 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.