A likely camping spot, a little dent in the chasm walls showed up ahead, and, as it was getting dark, Sid decided to stop here and make camp for the night, still keeping a wary eye out for whatever beast it was that was stalking them. He dismounted and picketed Pinto in a little grass swale. Then he cleared away a space for his fire in the needles that lay under the clump of silver spruces in the dent. He was gathering sticks for it when Pinto gave a snort of terror and tugged frantically at his halter. Sid yelled at him, for his eyeballs showed white with fright. He snatched up his rifle to peer down the chasm. Then a shock of alarm went through him, as his eye fastened on a motionless head--looking at them from over a ledge that jutted out from the canyon walls high up. Big, round, and coal-black it was! No ears showed--they must have been laid back flat--but a green and phosphorescent flash came from the two eyes in it that glared at them. Sid’s rifle sprang to shoulder and the red spurt of flame from its muzzle split the semidarkness. CHAPTER IV LOST CANYON For the next few seconds after that rifle shot, Sid was fully occupied. The black head, whatever it was, disappeared in the cloud of smoke from the rifle muzzle, and Sid heard a hoarse, ropy, animal snarl and a scramble in the bushes up on the cliff ledges. But Pinto had reared high in the air at the shot, and, with a whinny of terror and a frantic tug of his head, had broken the picket lariat. He dashed snorting across the ravine. Sid dropped his rifle and fell on the dangling lariat weaving like a snake through the grass. It whipped out from under him as he made a last snatch for it and a half hitch of it caught around his wrist. Sid was yanked to his feet, hauling against the plunging horse, and was dragged across the chasm. Only its sheer wall stopped Pinto in his mad frenzy of backing. Sid snubbed the lariat around a stump and let Pinto buck. Gradually the horse grew quiet as Sid talked to him, and he finally was able to come up on the rope and soothe him. The pony shivered with terror, but slowly became more easy, pricking his ears and looking with alarmed eyes down the chasm every time the thought of that creature that had peered out at them recurred to his equine brain. Sid led him over to the grass swale, where he fell to grazing again. After a time the pony seemed to know that their visitor had gone, for, save for an occasional stoppage to look long and intently, he went on feeding. But that was no guarantee that the prowler might not come back again, sometime during the night, reasoned Sid.