Ashton flung himself on his knees beside the triple knot that held the line fast to its spike. This time he did not hesitate, but began to tug at the rope end with fierce eagerness. He loosened one knot. The next was harder to unfasten. Blake had tied it with utmost secureness. At last it yielded to the tugging of his gloved fingers. He started to loosen the third knot. Suddenly the taut line slackened. With a stifled cry of rage, he paused to peer over the edge. Blake had slipped down the line so rapidly that he was already at the foot of the cliff. Reaching back, Ashton jerked the rope from the spike-head, to cast it down on the engineer. A glimpse of the flashing water in the canyon bottom gave momentary check to his vengeful impulse. If only he had a drink of that cool water! He was parched; his lips were cracking; in his mouth was the taste of dust. Must he stay up here on the dry rock while Blake went on down beside the foaming river to drink his fill? As he paused, a doubt clutched his heart in an icy grip. All the way down that devil's stairway he had been witness to Blake's extraordinary resourcefulness and tremendous strength. What if he should find a way to clamber up the precipices? He had lowered everything before descending. There was nothing to fling down upon him--no loose rock or stone to topple over and crush him. Chilled by that doubt, Ashton hesitated, his hands alternately tightening and relaxing their grip on the rope. What if the man should contrive to escape? There seemed no bounds to his ingenuity.... No, he must be followed on down into the canyon and destroyed, else he would escape--he would come up out of this inferno, like the demon he was, and destroy _her_. He must be followed!... And the water--the cool, refreshing water! His thirst now seized upon Ashton with terrible intensity. Rage, no less than the laborious exertion of the descent, had dried up his body with its feverish fire. Almost maddened with the torment of his craving, he looped the rope on the spike-head with reckless haste and slid down over the edge of the cliff. As the line tautened with his weight it gave several inches, but he was too nearly frantic to heed. He slipped down it so swiftly that the strands burned his hands through the tough palms of his gloves. In a few moments his feet were on a level with Blake's head. He clutched the rope tighter to check his fall. An instant later he dropped heavily on the rock shelf at the cliff foot, and the rope came swishing down after him. "God!" shouted Blake. Involuntarily he flung back his head and stared up the great gorge to the faraway heights where were waiting his wife and child. But Ashton neither paused nor looked upward. Rebounding from his fall, he rushed down the slope to the river, with a gasping cry--"Water! water!"