ome rascal, an' telephoned you, then
hustled over here."

"That's it," said Bob. "That explains it. I was wondering why whoever
set this fire didn't make a more complete job of it, but I see now.
You probably scared him away."

"Might be," said Tom. "He might a heard me callin' to Old Davey as I
run past his cottage."

"Well," said Frank, "let's push the bus inside. She's not much good
till we get new wings, but we don't want to leave it out here all
night."

All lent a hand, and then as he started to swing shut the doors Bob
examined the lock and gave an exclamation.

"Not even broken open," he said, disgustedly. "I must have forgotten
to lock up when we left. Good night."

This time, he fastened the lock, and then fell in with his comrades
and the party started for their homes.

"Whoever did that wasn't far away," Captain Folsom said, thoughtfully.
"If we had made a search we might have gotten some trace of him. But
it is too late now. I imagine, of course, as I said to Mr. Hampton
here earlier, that our bootlegger friends set the fire. When they
discovered your airplane in their neighborhood, they feared it would
interfere with their plans and decided to get rid of it."

"Well, they got rid of it, all right," said Bob, "for to-night,
anyhow, as well as for some time come."

They proceeded in gloomy silence for the most part, although the voice
of Old Davey, an incorrigible conversationalist, floated back to them
from where he led the way with Tom Barnum. Where their courses
diverged, the pair waited for them to call "Good nights."

"I say," said Jack suddenly, to his companions as Tom and Old Davey
departed; "I have an idea. Let's go over to the radio station, just
for luck, and listen in on the ether to see whether we can pick up the
interference on the 1,375-meter wave length. Maybe, we can get some of
those dots and dashes, too, of which Captain Folsom spoke. It's only a
step or two out of our way."

Bob yawned sleepily but stumbled ahead for the station, without a
word, and Frank fell in with him. Jack called to Tom Barnum and ran
ahead, leaving Captain Folsom to proceed with his chums.

When the others arrived, the door of the station's transmitting room
stood open, the lights were turned on, and Jack already was seated at
the instrument table, a headpiece clamping the receivers to his ears
while he manipulated the tuner.

Bob slumped down on the outside step, and Frank took a seat beside
him,