iver, much far past same tourist use. Sabe, Flank, Blob?"

The two boys stared at each other, unable to say a word at first. It was
as if the same tremendous thought had come to each.

"Gee whiz! did you get on to that, Frank?" finally ejaculated Bob.

"I sure did," replied his chum, allowing his pent-up breath full play.

"Charley says he engaged himself to a gentleman long ago; perhaps it was
as much as three years back, the time that the professor disappeared
from the haunts of men. And, Frank, his part of the contract was to come
to a certain point away up here in the Grand Canyon, once every two
months, at a time agreed on, bringing a load of food, as per the list
given him by this mysterious party."

"It must be Professor Oswald!" exclaimed Frank. "I've been wondering all
the time how under the sun he could have supplied himself with food
these long months if he'd cut loose from the world, as he said in that
note he had. Now the puzzle begins to show an answer. Charley Moi is the
missing link. He has kept the professor in grub all the time. Did you
ever hear of such luck? First we run across that old Moqui, who has been
in touch with the man we want to find; and now here's the one who comes
up here every little while to deliver his goods, and get a new list, as
well as money to pay for the same. It's just the limit, that's what!"

He turned to the Chinaman, and continued:

"Did you happen to notice, Charley, whether this party you are working
for is a bald-headed man? Has he a shining top when he takes his hat
off; and does he bend over, as if he might be hunting for diamonds all
the time?"

The Chinese guide smirked, and bobbed his head in the affirmative.

"That him, velly much, just same say. Shiny head, and blob this away
alle time," with which he walked slowly forward, bending over as though
trying to discover a rich vein of gold in the seamed rock under his
feet.

"Shake hands, Bob," said Frank. "We're getting hot on the trail. Now we
needn't have any doubt at all about the choice of the eastern route.
It's the right one; and somewhere further on we're just bound to find
Echo Cave."

"Then all we've got to fear, Frank, is the work of Eugene and his crowd.
Let us keep clear of that bad lot, and we're going to succeed. Any time,
now, we may glimpse our old Moqui, returning with a message from the
professor, if he sees fit to reply to your appeal. He may, though, be so
set and stubborn that nothing