He had taken the risk of entering Crawford’s room and secreting himself there partly to witness whatever might happen, and partly because he was by no means sure of James Stone. One never can be certain of what a madman may do. Stone had been supplied with the instruments necessary for the commission of a highly scientific crime, but when the time came, he might discard them, owing to his unfamiliarity with such things, and resort to some more commonplace weapon. In fact, if he made a slip, or if Crawford awoke prematurely and showed fight, it was almost certain that Stone would try to make us of some more familiar way of getting rid of enemies—or supposed enemies. Consequently Nick wanted to be on hand to give instant aid, if necessary. He did not consider that his duty to Crawford had been discharged when he had substituted water for the mysterious and deadly charge which Doctor Follansbee had originally placed in the hypodermic syringe. Stone came in noiselessly, and the subdued light from the corridor which shone in through the transom accentuated his lean, angular form as it entered. The door was closed carefully behind him, and Nick could hear his suppressed, nervous breathing as he crossed toward the bed. The intruder paused there within a yard or so of the outstretched form of Crawford, and Nick braced himself in anticipation of a possible emergency. He saw Stone looking toward the bed with his head thrust slightly forward, as if he were listening to Crawford’s breathing. Seemingly the man soon became satisfied that all was well, for he took from his pocket a couple of small objects which the detective guessed to be the little vial and sponge. Stone’s movements indicated that he was emptying the contents of the vial into the sponge. As he did so, he took a quick step forward and bent over the bed. Simultaneously there was a stir, and the springs of the bed creaked. Nick peered out and saw the head and shoulders of Crawford rising from the pillow. The bearded face of the kindly mine owner peered for a moment through the gloom at the vague form bending over him, then a single word came to the detective’s ears: “Jimmy!” A savage cry sounded, and, with a last bound, the demented partner had thrown himself upon Crawford. Nick heard a choking gasp, and for a moment was tempted to leap from his hiding place and hurl himself upon the would-be murderer. It was only with a supreme effort of will that he kept himself in hand and mutely watched the struggle. Stone had all the strength of his madness behind him, and with remorseless force he pressed Crawford back upon the pillow. Then, with a quick swoop, he pressed the sponge over the bearded lips and nostrils of the man who loved him better than a brother. There was a convulsive movement of the prone figure, and a long-drawn sigh, then Crawford’s arms fell back from their hold on Stone’s shoulders and he relapsed into unconsciousness.