an arm over his chum's
shoulder.

"Steady, Jack," he said. "Everything's going to be all right."

The friendly gesture and the sympathy in his chum's voice did steady
Jack.

"All right, now, Bob," he said. "Just at first, though----"

"Righto," the big fellow answered. "I'm scared stiff myself, and I'm
not even going into the ranch. If I were in your boots I'd probably be
shaking myself loose from them."

The pleasantry was what Jack needed. He grinned at the thought of big
Bob shaking so much with fear as to shake off his shoes, and his
recovery was complete.

The plan was for Jack, in the dress and character of Morales, to go to
the ranch house, enter boldly and make his way to the room where his
father was held prisoner. Bob was to stay with the plane. Releasing
his father, Jack would return with him. Then they would all three fly
away across the international boundary to the north.

It was impossible to foretell, of course, what obstacles to the
carrying out of this daring proposal would arise. Both boys felt
certain, however, that so far they were not suspected, and that first
Jack and then Frank had successfully thwarted the attempt of Morales
to send a warning to the ranch by radio.

Neither was aware, of course, that the jumble of sounds through the
air, when Jack from the airplane had interfered with Morales' attempt
to warn the ranch, and later the code conversation between Jack and
Frank, after the latter had obtained possession of the radio plant in
the cave and had overcome Morales, had aroused the curiosity and then
the suspicions of the young German, Muller, who operated the radio
plant at the Calomares ranch.

A few moments before the beat of its engine in the sky signalized the
approach of the airplane, Muller had decided to go to the ranch and
report to Calomares. He had crossed the landing field afoot and had
just reached the belt of trees when the machine volplaned to the field
behind him.

Although, as has been said, his suspicions were aroused, Muller was
far from suspecting the truth. He had no idea the airplane had been
recovered by its rightful owners and that these latter were about to
make a daring attempt to rescue Mr. Hampton. His thought on the
contrary, was that something--he could not make a more definite
surmise--had gone wrong at the cave.

Therefore, when, after standing several minutes at the belt of trees,
gazing back toward the airplane, he saw a figure start from it