“I—I don't understand it,” said the old man, turning pale.

“I do. He has cut a hole in the door, slipped back the bolt, and escaped. When could this have happened?”

“I don't know. Yes, I do remember, now, being disturbed last night by a noise in the entry. I got out of bed, and looked out, but could see no one.”

“Did you come up-stairs?”

“Part way.”

“When was this?”

“Past midnight.”

“No doubt that was the time he escaped.”

“That accounts for the door being locked,” said the old man, thoughtfully.

“What door?”