"Oh, we'll find a motive all right. Wait till we've turned up the earth in his tracks. Wait a few days."
"This 'other man,' O'Mally," said Mr. Whitney, "have you any ideas about him?"
"There you got me stumped," said the detective. "Of course we don't know Harland's inner life—had he an enemy and if so who? But—" he paused and let his glance move over the faces of the two young men. "If the thing hadn't been physically impossible I'd have turned my searchlight eye on Johnston Barker."
"Barker!" exclaimed Mr. George. "But Barker was——"
O'Mally interrupted him with a wave of his hand—
"I said it was physically impossible."
The old man got up, shaking himself like a big, drowsy animal and came forward into the lamplight.
"Nevertheless, gentlemen," he said quietly, "I'm convinced that it was Johnston Barker."
They all gaped at him. I think for the first moment they thought he had some information they hadn't heard and waited open-mouthed for him to give it to them. But he stood there, smiling a little, his eyes moving from one to the other, sort of quizzical as if their surprise tickled him.
"Now, father," said Mr. George, "what's the sense of saying that when we know that Barker was on the floor above, unable to get out without being seen?"