It was Bud who made the real discovery which, eventually, led to the solving of the mystery. Bud had alighted from his pony, when the halt was made for the noonday lunch, and was climbing up the side of the rocky hill which extended for miles and formed one wall of the gorge.
"Looking for gold?" asked Dick, as he saw his cousin pick up and examine several rocks.
"Sure!" was the laughing answer. "Might find the bones of another
Triceratops, too!"
Bud reached forward to pick up something else, and a rock slipped from beneath his foot. He had been resting heavily on it, and the sudden lurch threw him backward. To save himself he clutched at the nearest object, which happened to be a bush growing in the side of the hill. For a moment it seemed that this would save the lad from at least sliding down the declivity, but the bush was not deeply rooted and, in another moment pulled out in the ranch boy's hands. He flung up his arms, and almost toppled over backward, but managed to throw himself forward, and then he slid down several feet.
"Hurt!" called up Dick, ready to hasten to his cousin's aid.
"No, but my shoes are full of gravel. Next time I come up a place like this I——"
Bud suddenly ceased speaking, and began to scramble up the side of the shale-covered hill almost as fast as he had slid down. Then, as he reached the place whence the bush had pulled out he seemed to be looking into some crevice or opening.
A moment later he turned, looked down on the party gathered in the defile below him, and shouted:
"I've found 'em! I've found 'em! Here they are, in one of the queerest places you can imagine! Come up here and look!"