It needed the united strength of the prince and Harry to lift the stone, which was a large one, with an iron ring in the center, and to place it in the cavity.

Having done this, they looked round.

The room was about eight feet long by six wide, and lighted by a long narrow loophole extending from the ground to the roof.

They deemed from its appearance that it was built in one of the turrets of the building.
"That was a narrow escape, Master Harry," the prince said.

"It would have been right bad news for my royal uncle if I had been caught here like a rat in a trap.