The window was shut and locked. He had only to loosen one end of the wire to withdraw the whole and place it in his pocket.

Descending the ladder and mounting to the room, he again opened the window and examined the two marks. Yes, there could be no doubt on the matter. The two marks were deeper and plainer than ever. His own wire had fitted the grooves left by a previous one.

He felt happy and proud of himself. At any rate, he had beaten the much-vaunted Dobell so far. So pleased was he at that moment, that if some peripatetic hawker had at that time cried out “prawns” for sale in the street, he would have lavishly treated himself to a pint, in spite of Bell and all her lessons in domestic economy.

But this rash ardour soon cooled, and no demand was made on his tendency to extravagance. He was not out of the wood yet, not by a long way, he told himself, as he surveyed the iron bars and the thirty feet fall to the ground.

“Supposing a man got to the window, how could he get through?”

He tried each iron bar. They were all solidly soldered into the stone window-sill. Look at them as he would, they baffled him. Even a child could not squeeze through. And then again, a ladder must have been used to mount to the window. The one he had just used himself he had borrowed from a painter who was at work on a house close by. But he remembered that the morning after the murder, with the possible idea in his mind that the murderer had got into the room from the chimney, he had searched the neighbourhood for some distance round, and had found no privately-owned ladder long enough, and no painters using ladders. It was a common burglar’s trick to enter houses this way, so he had looked, and carefully looked, but he had found no sign of ladder, or even marks of where a ladder must have stood if it had been used.

His mind was in a turmoil. He thought and thought, but could see no way out. At last, in despair, he went home to tea, and relieved his mind by telling his discovery and his troubles to his wife. He had another matter on his mind that worried him also. At the Golden Bar, which he had visited more than once, he had had pointed out to him the person of Huey Gosper, and the man’s aspect had struck him as familiar, but for the life of him he could not bring to mind in what way or under what conditions he had seen him before.

Mrs. Hobbs was rejoiced at her husband’s news.

“Didn’t I say so, Tom, you would find it out? I always had my doubts about that window, though you were so positive! Why did you not look before?”

“Why indeed!” echoed Tom. “Why don’t we do fifty things that are plain enough to us after we have lost the opportunity?”