Abington gave him a sharp glance, but Bill was innocent and looked it. “It doesn’t matter now,” Abington said, “since I shall probably spend a week or more exploring these ravines. There should be a good many artifacts left in the caves hereabouts. The carvings indicate that the ancient people lived here and I have an idea that their occupancy of this section of the country extended over considerable period of time. This old Cretaceous sandstone gives every--” “Yeah, and it’ll give ’em just the same to-morrow, don’t you think, professor? I’m going to take what’s left of the flour and cache it away in my cave, and that can of coffee. Looks to me like the thing was scared off before it finished the job. All the times I’ve saw it get in its work before now, it sure was thorough! You must ’ave scared it--” “In that case I may be able to catch it.” Abington turned and strode again to where the tracks lay printed deep in the packed sand. He stepped down off the ledge and followed the hoofprints, scanning each one sharply as he came to it. “Hey! You can’t trail that thing, professor!” Bill called anxiously. “I tried that--once when it was a sheep and another time when it was a mule. Tracks take to the hills and quit. “Aw, gwan and find out for yourself, then!” he grumbled, when Abington merely flung up his hand to show he heard and continued along the wash. “Won’t be satisfied to take my word--never seen such a bullheaded cuss. But it won’t be long, old boy, till you’ll be tickled to death if you’re able to dodge it!” Dusk deepened. Bill hurriedly salvaged what supplies were not utterly destroyed, looking frequently over his shoulder when his work would not permit him to keep his back toward the cliff. It seemed a long while before Abington returned. Bill’s uneasiness had reached the point where he threw back his head to send a loud halloo booming out into the darkness; but at that very moment Abington came stumbling up to the ledge, leaning heavily on a dead mescal stalk while one foot dragged. Bill leaped forward and pulled him up the slope. “Rock rolled down the hill and started a slide,” Abington explained in a flat, tired tone. “Dodged most of the rubble, but one fragment struck against my ankle. Temporarily paralyzed my foot. Be all right in a short time, Bill.” He sat down, breathing rather heavily. “Who done it?” Bill knelt and tentatively felt the injured foot. “No one, so far as I know. I am not sure, of course, but my impression is that the slide was purely accidental.” “See anything of your sheep?” “Too dark to detect any signs after it took to the rocks. Heard something--up the hill. Couldn’t exactly locate the sound. Any coffee, Bill?”