Suddenly Bud, who had just taken up a piece of fruit cake, part of a chunk that his pretty sister Nell had sent over from the main ranch house a day or so before, stopped chewing in order to listen better; for, as you doubtless know, the action of the jaws precludes keen attention to outside sounds.
"What's the matter?" asked Dick, noting his cousin's act.
"I heard something," Bud answered.
"I'm hearing things all the while!" declared Dick. "This is the most weird place for mysterious noises I ever struck!"
"But this is different," insisted Bud. "Listen!"
Nort and Dick stopped chewing and strained their ears to catch the sound that had attracted Bud's attention. A strange, rushing, whispering echo seemed to fill the tunnel.
"Doesn't that sound like rushing water?" asked Bud.
"Yes," agreed Dick, after a moment of intentness; "it does."
"Look out!" quickly yelled Nort. "It is water, and on the rush, too! Jump for your lives! It's a flood!" and making a grab for one of the lanterns, that they might not be left in total blackness, he sprang toward the rocky side of the tunnel, an example followed by his companions.
And the rush of waters filled the underground cave with a mighty, roaring sound.