s. How do
you feel about it, Bob?"

"Nothing would please me better," replied the other boy, quickly, his
face lighting up with delight at the prospect of a long ride in the
saddle, to be followed by days, and perhaps weeks, of roaming through
that wonderland, where Nature had outdone all her other works in trying
to heap up astonishing surprises.

"So far as I'm concerned," Frank went on, "I've always wanted to visit
the Grand Canyon, and meant to do it some day later on. Of course I've
seen what the little Colorado has to show, because it's only a long
day's ride off. Mr. Hinchman can, I reckon, give us some points about
the place, and maybe even mention several smaller canyons where we might
be likely to find Uncle Felix in Echo Cave."

"Which I'll be only too happy to attempt," answered the gentleman from
Mohave City; "and as I said before, I know considerable about the
mysteries of the big hole in the desert, all of which is at your
service. Somehow, the queer way that message in the floating bottle came
to me, excited my curiosity; and I'll be satisfied if I can only have a
hand in the finding of the noted gentleman who, as your father has been
telling me, vanished in the midst of his fame."

"And now, dad, please explain just what we are to do in case luck
follows us in our hunt, and we run across the professor," said Frank.

"You are to explain to him that the long option which he held on that
San Bernardino mine will expire in one more month. The work had been
going on in a listless way for three years. All at once some time back
they struck a wonderfully rich lode, and vein has been followed far
enough to show that it is bound to be a record breaker."

"That sounds great!" declared the deeply interested Bob.

"The mine couldn't be bought for a million to-day," continued the
stockman; "and yet Uncle Felix is probably carrying around with him (for
it couldn't be found at his home) a little legal document whereby it
will become his sole property in case he chooses to plank down the
modest sum of twenty thousand dollars by the thirtieth of next month!"

"Whew! that's going some, eh, Bob?" exclaimed Frank, with a little
whistle that accentuated his surprise.

"Then if we are fortunate enough to find Uncle Felix before that time
has expired, what shall we do, sir?" asked the precise Bob, who was
always keeping an eye out for the legal aspect of things.

"Coax him to accompany you to the nearest notary pub