Round and round moved the weaving shifting forms, out of the dark and into the dark, a gray spectral line like a procession of ghosts, or some morris dance of the desert's sheeted dead. But it was not a line, it was a sea of forms; not a procession, but the even surging of a maelstrom of hoofs a mile around. Wade galloped out on the plain for a breath of air and a look at the sky. A quick cold rain would quiet them; but there was not a feel of rain in the darkness, no smell of it on the air. Only the powdery taste of the bitter sage. The desert, where the herd was camped, was one of the highest of a series of table-lands, or benches; it lay as level as a floor, rimmed by a sheer wall of rock from which there was a drop to the bench of sage below. The herd had been headed for a pass, and was now halted within a mile of the rim-rock on the east, where there was a perpendicular fall of about three hundred feet. 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 the nearness of the precipice. 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 rim. 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 the 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 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 stirless desert night, with the tension of the herd at the snapping-point, any quick, unwonted sight or sound would stampede them; the sneezing of a horse, the flare of a match, would be enough to send the whole four thousand headlong--blind, frenzied, trampling--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 measures 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 their hearing any loud and 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.