“It must have taken centuries for the river to have cut such a deep valley,” said Tom, looking down as they flew far above it.

“Some say that the river didn’t cut it,” said Zeb.  “They claim that there was a big earthquake or some sort of a shake-up, and that made that big hole in the ground.”

Below them they could see birds circling above the swiftly racing waters flecked with white foam.  So far no sign of land answering the description of Rattlesnake Island had come in view.  But several small, isolated spots of land were encountered, and on one, which looked something like Rattlesnake Island described on the map, they descended.

The boys were delighted at the way the great Wondership settled down into the canyon and then came to rest on the back of the island round which the water rushed and roared.  They scattered and ran about on it, enjoying the opportunity to stretch their legs.

Jack, Tom and Dick took a rifle along with them and they were glad they had done so, for as they made their way through a patch of brush a beautiful deer sprang out and dashed off.  Jack had the rifle at his shoulder in a minute and the creature bounded into the air, as the crack of the report sounded, and then fell dead.

The boy felt some remorse at having killed it, but he knew they would be in need of fresh meat and some venison would be a welcome addition to the ordinary camp fare.  The boys carried the deer back and Zeb skillfully skinned and quartered it.  While he was doing this, the boys speculated as to how the animal could have come to the island.

Zeb set their discussion at rest by explaining that it had probably swum the rapids to escape a mountain lion or a lynx.  He said that he had often shot deer under similar conditions.  As it was almost noon, they decided to wait on the island till they had eaten lunch.  Zeb sliced off some venison cutlets and cooked them to a turn over hot wood coals.  The boys thought they had never tasted anything better than the fresh meat.

While the plates and knives and forks were being washed and put away, the professor wandered off on his perennial quest of rocks and specimens.  He said that he would be back in a short time but was anxious not to miss the opportunity of finding some possibly rare stones.

But everything was ready and the boys were waiting impatiently half an hour later, and there was no sign of the professor.

Suddenly they heard his voice shouting to them from the distance.

“What’s he saying?” asked Jack.

“Hark!” admonished Tom.

The professor’s shouts came plainly to their ears the next minute, borne on a puff of wind that swept through the canyon.

“Help!  Help!” was the burden of his cries.  “Get me out!”

“Now, what’s happened to him?” demanded Zeb, with a trace of impatience.

“I don’t know, but he must be in trouble of some sort,” cried Jack.