They each led into an empty room, dusty and cheerless, with two windows in the one and one in the other, so thick with dirt that the evening light glimmered dimly through them.

The centre door was closed, and across the outside of it had been fastened one of the broad bars of an iron bed, padlocked at one end to a ring in the wall, and fastened at the other with stout cord.

The door itself was locked as well, and the key was not there.

This barricaded door corresponded clearly with the shuttered window outside, and yet I could see by the glimmer from beneath it that the room was not in darkness.

Evidently there was a skylight which let in light from above.