No, there was only one thing to do, and that was to arrive at an early hour.  Moreover, there would be this advantage attached, namely, that sentries would be lax and that, with many persons coming and going in and about the ranch, the passage of a familiar figure, such as they would take Jack to be, would arouse no comment.  Jack might be halted, of course, by some one desirous of conversation.  But he could make some excuse to pass on.  As a matter of fact he planned to wrap a handkerchief about his jaw and pretend to be suffering from toothache.  This would serve the double purpose of partially hiding his features, and of excusing him from indulging in extended speech.

“All right,” said Jack, finally, as he finished donning his disguise by clapping Morales’ hat on his head.  “Let’s go.”

“Ya, ya,” said Bob, doing a goosestep.  Once more they all had a good laugh.  Then Bob and Jack walked into the outer room of the cave, followed by Frank and Roy Stone.  Stone had thrown caution to the winds, and had decided not to try any longer to hide his defection from Morales and Von Arnheim.

“I’ll soon be riding away from here with you, anyhow,” he told Frank.  “And they’ll find out then, if they haven’t already suspected.  I’m going down to the airplane to see the kids off.”

Frank had demanded this privilege of going down to the valley and seeing Bob and Jack get away, and the others had no thought of denying him.  So all four, bearing the oil torches kept in the cave by Stone for the purpose of lighting the landing field at night, descended from the cave.  Tom Bodine was left to guard the two prisoners.

These had again suffered the ignominy of having their hands tied, after they had undressed, and, wrapped in the rubber ponchos given them by Bob, they had flung themselves down on the pallet prepared the previous night by the boys.

Stationed in the outer entrance of the cave, Tom Bodine looked around at the two prone forms several times.  But always they lay motionless under their ponchos, and there seemed no cause for suspicion regarding them.  Poor fellows, thought Tom, who held no particular animosity against them, they had had a hard time of it lately.  After landing from a flying trip, they had been set upon and beaten.  Then, made prisoner, they had spent the intervening hours cramped in bonds and in doubt as to what their captors intended doing with them.  Probably were tired out and asleep by now, thought Tom.  He even tiptoed over to where they lay and found, as he had expected, that both had their eyes closed and were breathing heavily.

Returning to the entrance, Tom took a step or two forward so as the better to see past the big rock outside and thus get a clearer view of the airplane.  The boys had reached it by now, the oil flares were planted to both sides, and it was illuminated, standing out in the tossing light like a great bird.

As the propeller began to whirl, Tom took another step or two forward.  An airplane was a new puzzle to him, and he was so interested in watching it get under way that he forgot his trust, forgot he had prisoners to watch, forgot everything but the mystery of that piece of mechanism, that gigantic bird, running bumpily now over the ground and now beginning to lift into the air, and now——­