She pressed it, and the stone, which was but slight, turned on a hinge, and disclosed an iron door.

This she opened with a spring, showing a small room within, with a ladder leading to another above.
"Mount that," she said.

"You will find in the chamber above a large stone.

Pull the ladder up with you and lower the stone, which exactly fits into the opening.

Even should they discover this chamber, they will not suspect that another lies above it." Prince Rupert, taking a light from her hands, hastily mounted, followed by Harry, and pulled the steps after him, just as they heard the iron door close.