He crept forward, halting often, eyeing the boulder and its neighboring ledge, distrust growing within him, though he saw nothing, heard nothing but the wind sweeping through branches and bush. Casey Ryan was never frightened in his life. But he was Irish born--and there's something in Irish blood that will not out; something that goes beyond reason into the world of unknown wisdom. It's a tricksy world, that realm of intuitions. For this is what befell Casey Ryan, and you may account for it as best pleases you. He circled the rock as a wolf will circle a coiled rattler which it does not see. Beyond the rock, built close against it so that the rear wall must have been the face of the ledge, a little rock cabin squatted secretively. One small window, with two panes of glass was set high under the eaves on the side toward Casey. Cleverly concealed it was, built to resemble the ledge. Visible from one side only, and that was the side where Casey stood. At the back the sloping boulder, untouched, impregnable; at the north and west, a twist of the ledge that hid the cabin completely in a niche. It was the window on the south side that betrayed it. So here was what the boulder concealed,--and yet, Casey was not satisfied with the discovery. Unconsciously he reached for his gun. This, he told himself, must be the secret habitation of the fiend who shot from rim-rocks with terrible precision at harmless prospectors and their burros. Casey squinted up at the sun and turned his level gaze again upon the cabin. Reason told him that the man with the rifle was still watching for a pot shot at him and Barney, and that there was nothing whatever to indicate the presence of only one man in the camp below. Had he been glimpsed once during the climb, he would have been fired upon; he would never have been given the chance to gain the top and find this cabin. The place looked deserted. His practical, everyday mind told him it was empty for the time being. But he felt queer and uncomfortable, nevertheless. He sneaked along the ledge to the cabin, flattened himself against the corner next the gray boulder and waited there for a minute. He felt the flesh stiffening on his jaws as he crept up to the window to look in. By standing on his toes, Casey's eyes came on a level with the lowest inch of glass,--the window was so high. Just at first Casey could not see much. Then, when his eyes had adjusted themselves to the half twilight within, his mind at first failed to grasp what he saw. Gradually a dimly sensed dread took hold of him, and grew while he stood there peering in at commonplace things which should have given him no feeling save perhaps a faint surprise.