. Hampton.

Bob returned to Frank, wearing a wide grin. "I couldn't resist putting
over that piece of propaganda," he said.

"Do you think he'll let us fly?" whispered Frank.

"Say," answered Bob scornfully, "now that Dad has decided to go along,
it's a cinch. He's as crazy about flying as Mr. Hampton is about the
radiophone."

"Ssst. Ssst," came a warning whisper, interrupting them. They swung
about to face the door into the power house. It was part-way open and
the round good-natured face of Tom Barnum, filled now with anxiety,
was framed in the opening. Tom was the mechanic-watchman. He beckoned,
and the boys tiptoed across the room and into the power house, closing
the door behind them. Old Davey, caretaker at the Hampton home, stood
there, wringing his hands.

"What is it? What's the matter?" Frank Merrick asked sharply.

"Old Davey says there's a thief up at the house," said Tom.

"A thief?" said Bob. "How do you know?"

"Seed him myself with my own two eyes," quavered Old Davey, a little
old man who was a pensioner of Mr. Hampton's. "He's a big dark
ugly-lookin' feller. I seed him a-sneakin' into the house through the
cellar door I left open to git out some garden tools."

"Then what did you do?" asked Frank.

"I run," said Old Davey, simply. "Leastways I tried to, but my legs
ain't what they used to be."

"Come on, Bob," said Frank, impulsively. "Let's go see."

"Not till we tell Dad, first," said Bob, as always the cooler.

Re-entering the sending room, Bob once more gained the attention of
his father, who still was in conversation with Mr. Hampton. He told
him what Old Davey had reported. Mr. Temple readjusted the headpiece
and swung about to the transmitter.

"Anything in your house a fellow could carry off in a pocket,
Hampton?" he said. "Because the boys tell me there is a thief in it
right now, and we're going up to try to catch him."

"I don't think so," said Mr. Hampton, and then added in a tone of
alarm: "Great guns, Temple, yes. There is. There's a duplicate list
among my papers that the Octopus would give anything to obtain
possession of. It's a list of the lessees out here in the oil fields
who have joined the independents."

"All right, Hampton," said Mr. Temple, "we're off."

Removing the headpiece, he hurried Bob back into the power house.
There he ordered Tom to switch off the motor, lock up and follow them.
Then accompanied by the boys and with Old Davey trotting alongside t