It was the last place an experienced plainsman would have chosen for a camp; and every time Wade circled the herd and came in between the cattle and the rim, he felt its nearness. The darkness helped to bring it near. The height of his horse brought it near--he seemed to look down from his saddle over it, into its dark depths. The herd in its milling was surely warping slowly in the direction of the precipice. But this was all fancy--the trick of the dark and of nerves, if a plainsman has nerves. At twelve o’clock the first guard came in and woke the second watch. Wade had been in his saddle since dawn, but this was his regular watch. More than that, his trained ear had timed the milling hoofs. The movement of the herd had quickened. If now he could keep them going and could prevent their taking any sudden fright! They must not stop until they stopped from utter weariness. Safety lay in their continued motion. So Wade, with the fresh riders, flanked them closely, paced them, and urged them quietly on. They must be kept milling, and they must be kept from fright. In the taut silence of the starless desert night, with the tension of the cattle at the snapping-point, any quick, unwonted sight or sound would stampede the herd--the sneezing of a horse, the flare of a match, enough to send the whole four thousand headlong--blind, frenzied, tramping--till spent and scattered over the plain. And so, as he rode, Wade began to sing. The rider ahead of him took up the air and passed it on, until, above the stepping stir of the hoofs, rose the faint voices of the men, and all the herd was bound about by the slow, plaintive measure of some old song. It was not to soothe their savage breasts that the riders sang to the cattle, but to prevent the shock of any loud or sudden noise. So they sang and rode, and the night wore on to one o’clock, when Wade, coming up on the rim-rock side, felt a cool breeze fan his face, and caught a breath of fresh, moist wind with the taste of water in it. He checked his horse instantly, listening as the wind swept past him over the cattle. But they must already have smelled it, for they had ceased their milling. The whole herd stood motionless, the indistinct forms nearest him showing, in the dark, their bald faces lifted to drink the sweet wet breath that came over the rim. Then they started again, but faster, and with a rumbling from their hoarse throats that tightened Wade’s grip on his reins. The sound seemed to come out of the earth, a low, rumbling mumble, as deep as the night and as wide as the plain, a thick, inarticulate bellow that stood every rider stiff in his stirrups. The breeze caught the dust and carried it back from the gray-coated, ghostly shapes, and Wade saw that they were still moving in a circle. If only he could keep them going! He touched his horse to ride on with them, when across the black sky flashed a vivid streak of lightning.