Alan laughed. "The place is barren as a barn floor," he said; "I don't see any very large palace or temple hereabouts."

"I don't either. That's why I'm going to look for it—and look hard."

"And our gas slipping away at a lively rate!" interrupted Alan again.

"Let it all go," said Ned. "We know how we can get down within a hundred feet of the ground, anyway. That's some consolation."'

"First we will make a circuit of the north end," continued Ned, after breakfast, "and if nothing comes of that—no unseen hollows or new crevices—we'll try this sandy hollow, even if it is smooth as a plain."

The circuit of a fifty-acre area requires time and it was an hour before the boys had traversed the edge of the precipitous cliff. At every few yards they examined the face of the mesa for gaps or shelves, but there seemed hardly a resting place for a bird.

Tired and hot, the sun being now high above them, the young aeronauts finally reached the north-eastern corner of the mesa without finding a sign or suggestion of Indians, or even of animal remains.

Alan had thrown himself on the ground at this point for a rest, when with an exclamation Ned darted from his side. As Alan's eyes followed him he saw the cause of the exclamation. From where they stood—directly east from the ancient grove—they could see for the first time that the trees stood in a wide double semi-circle, and, directly in the center, perhaps fifteen feet in height, arose a column of masonry. It was snow white in color and glistened like glass.

There was no question about it.

The fabled Temple of Turquoise, its deep blue glaze lost in the whitening sun of three centuries, stood before them. Almost overcome with the emotion of success the two boys stood as if transfixed. Then cautiously, as if afraid the wonderful pile might dissolve itself into a dream, they moved forward.