“Get around to the right,” he said, “and keep close to Sud, Bill. I’ll lead in myself. Take it slow. Don’t want ’em to jam in the neck. When the first ones start behind th’ Flange let ’em dribble in on their own time. All ready?” The last two words were a high call addressed to all the men. From all sides of the herd, come to a full stop now, came replies and Selwood saw Caldwell ride away around to the right. Turning his horse the sheriff followed promptly. He was tense as a wire, alert, dreading discovery every moment, yet filled with an excitement which sent the blood pounding in his ears. As he neared the face of the precipice on the right, he saw Provine sitting on his horse, saw Caldwell circle in to the wall and cutting in before the massed cattle, go straight along its length. The faint starlight was just sufficient to show up bulk and movement, not detail. He heard the foreman begin to call “Coee—coo-ee—coo-ee”—and the next moment he could not believe his eyes, for horse and rider melted headfirst into the face of Rainbow Cliff, as a knife slices into a surface and disappeared! Caldwell’s voice came from the heart of the wall, far away and muffled, calling “Coo-ee—coo-ee”—Provine edged in against the steers, shouting, he followed suit, as to movement, though he did not speak, and the dark blot of the mass began to flow into the solid rock of the spine that crowned Mystery Ridge! Sheriff Selwood had solved the mystery of the disappearing steers—knew to a certainty who were the rustlers of Nameless River—and he could not get away with his knowledge quickly enough. Therefore he reined his horse away to the left, dropped back along the herd, edged off a bit—a bit more—sidled into a shadow—slipped behind the pine that made it—and putting the bay to a sharp walk, went down the mountain. As the sounds behind him lessened he drew a good breath and struck a spur to his horse’s flank. And right then, when there was most need, the good bay who had served him so long and faithfully, betrayed him. He threw up his head, flung around toward the strange horses he was leaving, and neighed—a sharp, shrill sound that carried up the slope like a bugle. At the mouth of the Flange Big Basford stopped. His own mount answered. Once more came that challenge from below and Sud Provine came back out of the hidden passage on the jump. “God damn!” he shouted, “that ain’t a Sky Line horse! Boys—we’re caught! Come quick!” Selwood, far down the trail, knew with a surge of rage that the game was up and that he was in for it. He knew in the same second, however, that his own horse was fresh, while those others were not. He clapped down hard with both spurs, got a good grip on his old gun, and sailed down the steep trail—“hell bent for election,” as he thought grimly. He had a fair start and meant to make the most of it. And he knew his horse.