“P’r’aps—p’r’aps it goes through a cave,” suggested Bob. “I’ve read about underground rivers, haven’t you?”
“Oh, shucks,” said Jerry. “Probably the way out is hidden just like the way we’ve come. Look back. You can’t see how we got in here, can you?”
Bob had to admit this was so. “Maybe you’re right. Anyhow, it’s so dark we can’t tell for certain. I think we’d better get ashore somewheres and make camp. We’ll find out about it in the morning.”
When they awoke the next morning the rounded chamber of the canyon was flooded with light.
“Find your ridge,” invited Bob politely, “the one behind which our river flows on and on and—”
“Oh, shut up!” was Jerry’s ungrateful retort. Since he had opened his eyes he had endeavored to find just that thing—with no success. But he would not own up until he had had another long look. But after a while he had to give in.
“Looks like you were right,” he said tersely. “The river must go through a tunnel, because it sure comes out on t’other side. This river is part of what goes through the Grand Canyon.”
Bob had the good sense not to gloat openly over Jerry’s discomfiture.
“All right,” was all he said. “But let’s find the mouth of the tunnel. Hustle up with the grub.”
They gulped their coffee and soon cast off, letting the stream carry them gently towards the face of the great obstruction. A few minutes later they saw the solution of this mystery. Under the cliff the river flowed swiftly and silently into a dark hole.