Suspended from the beautiful redbrick arched ceiling, the hooks used to help winch the seven-tonne cannons, also manoeuvred into place using grooves onthe flagstone floor.

He has been joined below ground by teams of telecoms engineers and now, just above his head, four thin cables snake along the arched ceiling and disappear into the darkness.

Huge windowed walls and a high arched ceiling were added in 1937.

An arched ceiling spanned some 50 ft in breadth, in the center.

Accessed through the first floor, its vaulted, arched ceiling rises up through the next so that it actually occupies two floors.