With returning consciousness, the thought of his dying friend recurred to him in all its vividness. He tried to go to his assistance; but he was sick and faint, and his limbs were powerless to respond to his will. Then, at last, he was seized with utter despair and gave up the struggle. He had sunk dejectedly upon the chair when a faint and indistinct murmur, as of distant voices, beat upon his ears, whose natural acuity seemed extraordinarily increased by the long nervous tension under which he had been. The ruling passion is strong in death; without knowing just why he did so, Sturgis found himself again at the speaking-tube, endeavoring to hear the conversation, the sound of which evidently came from Murdock's office. He could barely distinguish a word here and there; but he recognized the timbre of one of the voices. It was the chemist's, and his interlocutor was a woman--perhaps his daughter. If only he could reach Agnes Murdock with some word or signal. In suspense, he held his ear to the mouthpiece, occasionally taking a breath of fresh air to renew his strength. Should he take the chances and shout in the hope of catching the young girl's attention? If he whistled, Murdock would answer himself, and the last chance would be lost. But would she hear a shout? And, if she did, would not her father prevent her from rendering any assistance? Yet what other chance was there? Poor Sprague was dying; perhaps already dead. There was no time to lose. He stood for a while irresolute, and had just made up his mind to risk all on a bold move, when suddenly Murdock's voice became more distinct, as if he were passing near the mouthpiece of the speaking-tube at the other end. "I shall be back directly." He was going, then. Agnes, if it were she, would remain alone for at least an instant; and in that instant lay possible salvation. The reporter strained every nerve to catch some other word. None came. But presently he heard a door close. Murdock had left the room. Now or never was the chance to act. With all his might he blew repeatedly into the tube. "Well?" The question came in the sweet tones of a woman's voice. "Mr. Sprague is in great danger. You alone can save his life, if you do at once as I say. Go to the door of the extension; press upward on the lower hinge; then turn the knob! Quick, before your father returns!" Sturgis evoked the image of Murdock performing these operations before opening the door of the extension; and, with retrospective intuition, divined their purpose. There was no answer. Sturgis waited for none. In a bound he was at his friend's side and was struggling to drag him toward the foot of the stairs. As he reached this point, the door opened and revealed Agnes Murdock, pale and frightened, on the landing at the top. The first rush of gas caused her to start back; but in another instant she had caught sight of her lover's inanimate form and had rushed to his assistance.