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."