ey Moi picturing his wonder on his moon-like
countenance.

So the prairie lad led them in and out among the rocks, and the scrub
that grew close to the verge of the river. Several times he seemed a
little in doubt, as the marks faded entirely away; but on such occasions
his common-sense came to the rescue, and, after a look around, Frank was
able to once more find the trail.

"Here's where it ends!"

When Frank made this remark Bob could not keep from expressing his
surprise.

He gaped upward at the bare-faced wall that arose for hundreds of feet,
without any particular ledge or outcropping where even a nimble Indian
could find safe lodgment for his moccasined feet.

"But, Frank, however could the old Moqui get up there to see Uncle
Felix?" he asked. "D'ye suppose he made some sort of signal, and the
hermit lowered a long rope with a noose at the end, which would draw him
up? Wow! excuse me from ever trying to fly in that way! It would make me
so dizzy I'd be sure to drop, and get smashed."

"You're beating on the wrong track, Bob," remarked the other. "No rope
could be lowered all that distance; and even if it could no one man
would be able to pull another all the way up."

"But there must be some way of getting to the place where the slits in
the face of the cliff tell of windows. However do you think he did it,
Frank?"

"Just because you don't happen to see a ladder, Bob, is no evidence
there isn't a way to mount upward. One thing about this great cliff I
guess you didn't happen to notice. That shows you pass things by. Look
again, and you'll see that it seems to have been split by some volcanic
smash, ages ago. There's a regular crevice running slantingly up the
face of the rock. You see it now, don't you?"

"Sure I do; and I was blind not to take notice of the same before," Bob
replied. "Fact is, I did see that uneven mark, but just thought it was a
fault in the make of the cliff, as a miner would say."

"Well, that crack extends four-fifths of the way up to the top; and far
enough to reach the place where we noticed all those dark marks, which
we believed must be windows of the many rooms or houses of the cliff
dwellers. Get that, Bob?"

"Sure I do, Frank, and after your explanation I can see what you're
aiming at. But where does that ragged crevice start from down here, do
you think?"

Frank stepped forward. Just as if he had it all figured out, he bent
down, and with his hand drew aside the bushe