“Look here, boys!” Jack finally called. “You remember the place in Mexico called the Devil’s Cauldron? Well, this is it!”
“What have you found now?” demanded Frank sleepily.
“Here’s a round hole in the mountain,” Jack answered back, “that you might hide a city block in. It’s deep and the sides are almost smooth. Looks like the pit Kipling gets one of his characters in, only there’s rock instead of sand.”
The boys rose to their feet and looked over the ledge.
“And right there in the bottom,” Harry exclaimed, “is a pool of water so clear that it looks like a diamond!”
“Running water, too,” added Frank. “Now, where do you think that water comes from, and where does it go to?”
“Runs through a pass, foolish!” answered Jack.
“But there’s no break in the formation,” Frank insisted.
“Then it runs through a tunnel manufactured by itself!” Jack explained. “Anyway, it gets out somehow.”
“What a dandy place to catch mountain trout!” shouted Harry.