Although Bob had anticipated such a thing, still the knowledge that it was actually coming to pass gave him a thrill. For some little time he did not say anything; but Frank could see him look uneasily up at the walls that now arose sheer above their heads some hundreds of feet. Frank had studied the situation as well as he could, both from a map of the canyon which he found in the little guide book, and his own observations. All the while he kept before him that admission on the part of the old Moqui whom they had befriended, to the effect that the Westering sun shone full in Echo Cave. So he expected to find the home of the hermit-scientist high up in the wall on the Eastern side of the Grand Canyon. First he intended heading toward the East, and going just as far as they could. Days, and perhaps weeks, might be spent in the search for the strange cave that had once been the home of those mysterious cliff people, which cavern Professor Oswald was occupying while studying the lives and customs of the long departed people who had dug these dwellings out of the rock. At noon they had made good progress; but when the tremendous size of that two hundred mile canyon was taken into consideration, with its myriad of side "washes," and minor canyons, the distance that they had covered was, as Bob aptly declared, but a "flea-bite" compared with the whole. And Frank declared time and again it had been a lucky thought that caused his chum to suggest that they bring the field glasses along. They were in almost constant use. Far distant scenes were brought close, and high walls could be examined in a way that must have been impossible with the naked eye. Of course Frank was particularly anxious to scrutinize every colored wall that faced the West. The rainbow tints so plainly marked, tier above tier, called out expressions of deep admiration from the two lads; but all the while they were on the watch for something besides. When Frank ranged that powerful glass along the ragged face of a towering cliff he was looking eagerly for signs of openings such as marked the windows of the homes fashioned by the strange people of a past age. During the afternoon they actually discovered such small slits in the rock--at least they looked like pencil markings to them when the guide first pointed out the village of the ancient cliff dwellers; though on closer acquaintance they found that the openings were of generous size. "Shall we climb up that straggly path along the face of the wall, and see what the old things look like?" asked Bob, as the guide made motions upward. "Yes, we ought to have our first sight of such places," Frank replied, in a cautious tone. "Not that I expect we're going to find our hermit there, or in any other village that's known to tourist travel. But we ought to get an idea of what these places are like, you see. Then we'll know better what to expect. And perhaps the conditions will teach us how to discover _his_ hiding place."