"Then it means that we have found the valley prison!" gasped Andy.

"Sure, that's a fact. The cliffs yonder are on one side of it!" Frank
cried.

"And Frank, don't you see, the fact that another of those little
messengers of hope has just come up out of the valley _shows that he is
alive_!"

"You just bet he is, Andy; and we're going to be with him in three
shakes of a lamb's tail!" declared the other.

Andy could not utter another word; he was too full of emotion. So he
just sat there and stared and waited, his heart doubtless thumping
against his ribs as it had never done before.

Of course, when Frank gave utterance to that boast he did not really
mean it, and only had the encouragement of his chum in view. He knew
that it was apt to prove a difficult task, landing in that enclosed
valley, where the vegetation must be of a tropical order.

First of all they must circle around over the wide expanse to take in
its features and discover the prisoner. Then Frank could lay his plans
accordingly.

Gradually they began to see more and more of those marvelous
cliffs. They seemed to stretch in an unbroken cordon completely around
the valley. If they were as near like adamant as they looked it would
take a man years to cut steps to the lofty top, even though he were
given proper tools for the work.

And presently they cleared the near side, so that the monoplane floated
directly above the valley itself.

"Careful now, Andy!" warned the cautious Frank. "Hold yourself tight
while we circle around, dropping lower all the time. Suppose you shout,
though I should think he'd have heard the noise of our exhaust before
now!"

He had hardly uttered these last words when there came a cry from below.

"Look, look, Frank, there he is! Oh, what a blessed sight that is! My
father, and alive after all! See how he runs and waves his hands! What
will he say when he knows that it's his boy in this airship come to save
him?"

"Call out and tell him!" said Frank, hardly able to control his own
feelings, though he knew he must or they might meet with an accident in
this supreme moment of victory.

So Andy did shout, calling upon his father wildly and waving his cap to
him. The prisoner of the enclosed valley seemed dazed at first. Perhaps
he had been deceived so many times by his dreams of being saved that he
feared this might prove only another delusion. They could see him stand
there and put his hand to his head as he stared