t? Could you see any signs here to
tell about that?"

"I suppose I could if they were here, but I don't discover any.
Besides, I thought of that before we entered, and I give you my word
that I don't believe any big volume of water ever went out through
here. It couldn't do it and not leave some sign behind."

Bob heaved a big sigh.

"Well, I'm right glad to hear you say that, Frank, seeing that we're so
far in now, we wouldn't have any chance to escape if it came along.
Whew! I wouldn't like being carried through here, and shot out of the
muzzle like a bullet. But seems to me the place is getting bigger
right along, Frank."

"Just what it is. Now you can see how like the neck of a bottle the
cave is; and I think that has had a heap to do with the way that
thunder noise gets loose. Why, they say that some days, or nights, it
can be heard more than twelve miles away. I've seen Navajo Injuns drop
flat on their faces, and lie there all the time we could hear the
distant thunder in a clear sky over our way."

"But is it possible that some hermit is living in this cave?" asked
Bob, thinking that it must be a queer sort of person who would remain
where he must listen to such fearful sounds every once in a while.

"I told you to notice when we heard the noise the first time," Frank
went on; "while we were in camp on the plain, that the night was clear,
and the wind almost in the Southeast. Well, I made sure that it was in
exactly the same quarter tonight when we were climbing the mountain.
That means something, Bob."

"To you; but to me it's only a blank," admitted the tenderfoot,
regretfully.

"I fancy that the direction of the wind has something to do with the
working of this queer old geyser in the heart of Thunder Mountain. It
only rears up when the wind is in the Southeast, as it is now. But
say, you said something about a hermit just now?"

"I only said I thought it strange a fellow could live here through all
the racket, year in and year out, just to get away from his kind," Bob
remarked.

At that Frank laughed.

"But what if he had a big object in it, Bob? What if some daring
prospector, taking his life in his hands, had plunged into one of these
caves of the winds, this one right here, for instance, and struck it
rich. Gold will make men do nearly anything. I've seen 'em go crazy
over finding a nugget, or yellow sand in their pan. Don't you see what
I mean, Bob? Have you forgotten little