After Mr. Slapperton had left, Giles knelt down before the door and scrutinised the lock.
After a minute examination of the same he came to the conclusion that it would be easier for him to dig a hole in the wall close to the lock, to wrench the staple away, and then force back the bolt as if it was being unlocked by a key.
He felt assured that this would be the best plan, but as he was rising from his knees he discovered something in the centre of the door which strangely enough had entirely escaped his attention before.
There was a small round grating a little larger than a man’s eye: a flap of iron hung before it on the other side.
Giles was astonished, as well he might be, at the discovery, and still more so at it having escaped his notice.
While he was staring at it and fingering it with a considerable amount of curiosity he heard a soft step, so soft that he did not think it was so close to him.
“Some one on the watch,” he murmured, as his heart beat audibly.
The flap was gently raised and its place was taken by a large brown eye, which sternly surveyed the interior of the cell.
As if satisfied with the impression it had made, the eye disappeared, and the iron flap descended as noiselessly as it had been raised.
Giles Chudley felt relieved when the scrutiny was over.