It is the summit of the next ridge that ever lures the explorer onward. What new sights lie just beyond? What mysteries will its achievement unveil to the eager eyes of the adventurer? Judgment and experience joined forces to assure him that when his eyes surmounted the ridge ahead they would be rewarded with nothing more startling than another similar ridge to be negotiated; yet there was always that other hope hanging like a shining beacon just below the next horizon, above which the rays of its hidden light served to illuminate the figments of his desire, and his imagination transformed the figments into realities. Von Harben, sane and phlegmatic as he was, was now keyed to the highest pitch of excitement as he at last scaled the final barrier and stood upon the crest of the ridge. Before him stretched a rolling plateau, dotted with stunted wind-swept trees, and in the distance lay the next ridge that he had anticipated, but indistinct and impurpled by the haze of distance. What lay between him and those far hills? His pulse quickened at the thought of the possibilities for exploration and discovery that lay before him, for the terrain that he looked upon was entirely different from what he had anticipated. No lofty peaks were visible except in the far distance, and between him and them there must lie intriguing ravines and valleys--virgin fields at the feet of the explorer. Eagerly, entirely forgetful of his hunger or his solitude, von Harben moved northward across the plateau. The land was gently rolling, rock-strewn, sterile, and uninteresting, and when he had covered a mile of it he commenced to have misgivings, for if it continued on without change to the dim hills in the distance, as it now seemed was quite likely the case, it could offer him neither interest nor sustenance. As these thoughts were commencing to oppress him, he became suddenly conscious of a vague change in the appearance of the terrain ahead. It was only an impression of unreality. The hills far away before him seemed to rise out of a great void, and it was as though between him and them there existed nothing. He might have been looking across an inland sea to distant, hazy shores--a waterless sea, for nowhere was there any suggestion of water--and then suddenly he came to a halt, startled, amazed. The rolling plateau ceased abruptly at his feet, and below him, stretching far to the distant hills, lay a great abyss--a mighty canyon similar to that which has made the gorge of the Colorado world-famous.