Thereupon he proceeded to tell his father of Roy Stone, the young American in charge of the radio plant in the cave, whom they had made prisoner.  A lengthy conversation ensued.  Mr. Temple was reluctant at first to have the boys reveal their identities inasmuch as so far they had escaped detection.  But he saw that if an ally could be made of Stone it would be of the highest importance to the boys.  He finally authorized Bob to promise Stone a suitable reward, if he thought that would appeal to him.  Then, enjoining Bob to take no further steps without first consulting him by radio, Mr. Temple concluded the conversation.

To Jack and Frank, speaking in low tones at the entrance to the cave where Frank kept guard, Bob explained the gist of his conversation with his father.  Tom Bodine still slumbered heavily.  Stone lay napping on his bed.  Morales and Von Arnheim sat with drooping heads in the heavy chairs where, while Bob telephoned, Jack had thought it best to bind them.

“Well, let’s talk with Stone and see what he has to say,” Jack said.  “Frank and I have been talking the situation over, too, and we’ve got all sorts of ideas.  For one thing, we thought there was a chance the rebels could be persuaded to exchange father for Von Arnheim and Morales.  Stone might know how important those two worthies are considered by the rebels.”

“Can’t I listen in on this confab?” Frank asked, plaintively.  “Or must I continue to mount guard here?  Besides, I want to go down and look at our airplane, and pat it even if I can’t get in and fly.  I can see it from here, and it looks tempting.”

“You’ll have to wait awhile to do that, I expect,” said Jack with a smile.  “We must decide what to do next before we spend any time playing.”

At that moment, Tom Bodine yawned prodigiously and sat up on his make-shift couch.

“At least I can have a voice in the conference,” said Frank.  “If Tom’s awake he can mount guard.”

“All right, fine,” said Jack.  “We’ll leave him out here with Morales and Von Arnheim, as soon as he has had something to eat.  Then the three of us can take Stone into the other room and have a talk with him.”

So it was arranged.

CHAPTER XXI

GAINING AN ALLY

Before mounting guard, however, Tom thought of their horses, a detail which the boys had forgotten in the quick march of events.  He and Bob descended the slope, brought the animals into the valley where there was grass along the bed of a little stream trickling from a spring, and a few trees that provided shade.  The horses were hobbled to prevent wandering too far, and then left to do as they pleased.  They pleased, every one, to lie down at once and roll.

Upon their return to the cave, after Bob first had inspected the airplane and found it in tiptop condition and stocked with gas and oil, Tom mounted guard while the boys carried out their intention of taking Stone into the inner room for a conference.