Frank looked around him eagerly.

"We must be getting warmer all the time," he remarked; "and if you just take a look at that river right now, you'll see that up yonder the rock rises up almost from its very flood. When the water is high it must sweep along against the face of that big cliff. And Bob, something seems to tell me that somewhere inside of a mile or so, we're going to find what we're looking for."

"Oh! I hope so!" echoed Bob, with a look of expectancy on his face; for he always put great reliance on the common sense of his chum; and when Frank said a thing in that steady tone, the Kentucky boy believed it must be so.

Frank called a halt then and there.

"We're tired, anyway," he said, "and might as well spend the night here. Besides, I just want to find a place were I can take a good look through the glass up at that cliff near the top. It faces the West, all right, you see; and the indications are that somewhere or other I'll find signs of the queer windows belonging to some of those cave houses."

The camp was made, and Charley Moi busied himself with his fire. Bob had some things he wished to attend to; while Frank took the glass, and, settling down in a place where he believed he could get a fair view of the upper strata of colored rock, began carefully scrutinizing the cliff.

"The time is right, because the old Indian said the Westering sun shone in the mouth of Echo Cave," Frank mused, as he pursued his work, not disappointed because failure came in the beginning.

Frank had been at work possibly six or eight minutes when he gave utterance to a low exclamation. Then he fixed his field glasses upon a certain spot as though something had caught his attention there.

"Bob!" he called out.

"Want me?" asked his chum from the spot where the fire was burning.