It was time for the watcher to become the man of action, and the transformation entailed considerable risk, as the detective knew. He did not mean to remain in idleness where he was; but, on the contrary, had determined to repeat his maneuver of some time before. In other words, he meant to crawl out on the fire escape once more and take a position outside of the miner’s window, in the hope that he could hear enough of the conversation between the two to enable him to get a clew to their intentions, if not with regard to Winthrop Crawford.
The sounds they had made with all their care had brought his danger home to him, and he realized that the necessity for climbing over the iron railing made it likely that he would cause even more noise. The attempt must be made, though, come what might, and Nick had already made preparations for it. He had anticipated the necessity, and had previously transferred a little instrument from one of his suit cases to his pocket.
It was a sort of disc made of hard rubber for the most part, and about an inch in thickness. Its use was obscure at first glance, but would have been sufficiently plain upon examination. It was a sort of ear trumpet designed for the deaf, but without the old-fashioned horn attachment.
He buttoned his coat once more about him, then proceeded to raise his window the required distance; but at the risk of missing something important, he took his time about it, with the result that the slight sound could not have been heard even a few feet away. When there was room enough for him to crawl through, he did so, and, leaning over, grasped the end of the platform. He stepped noiselessly across the gap, threw one leg over the railing and gently lowered himself to the grating. Along this he tiptoed, his thin-soled shoes making practically no sound as he advanced. In a few moments he was kneeling in front of Stone’s window with the rubber disc held to his right ear, and his ear lowered to the crack at the bottom of the sash.
The wooden wedge was still in place, luckily for him, consequently the sash had remained slightly raised. As soon as the device was brought into use, it amplified the sounds it caught, and what had been an indistinct murmur of voices became an easily audible conversation.