"A good idea, Bob. Just notice where the chances look half-way decent for a climb. And remember, at the same time, that the wave may be all of thirty feet deep when it sweeps through here."
"You don't say? That would mean some hustling then to get up out of reach, Frank."
"I reckon it would. Look out for that nasty rock; it nearly tripped me, Bob."
"What was that flash, Frank? Don't tell me it was lightning, real lightning, and that the long delayed storm is going to break right now, when it's got us cooped up in this hole?"
"It was lightning, all right. There, that proves it!"
Frank's words were drowned in a crash of genuine thunder that made the foundations of the mountain shake just as much as the mad efforts of the imprisoned geyser had ever done.
"No mistake about that sort of thing," cried Bob, as he stumbled along after his chum. "There it comes again, Frank. I guess I'd better be picking out a good way up the wall somewhere, for it looks like we'd have to climb!"
Frank was doubtless sizing up the situation in his mind. He was also listening for some sound which he expected to hear, but which was going to prove a very unwelcome one.
"No use going any further, Bob, if so be you've seen anything that looks promising here," he declared, when the reverberations of the thunder had ceased to echo through the canyon.
"Then you think we're going to get caught here, Frank?" questioned the other.