ed off with a roar, and a succession of
explosions that were deafening, until Tom switched in the muffler,
thereby cutting down the noise. Faster and faster the propeller
whirled about as the motor warmed up, until the young inventor
exclaimed:

"That's the stuff! She's better than ever! Climb up Ned, and we'll
start off. You can turn her over, Rad; can't you?"

"Suah, Massa Tom," was the reply, for Eradicate had been on so many
trips with Tom, and had had so much to do with airships, that to
merely start one was child's play for him.

The two youths had scarcely taken their seats, and the colored man
was about to twist around the fan-like blades of the big propeller
in front, when from behind there came a hail.

"Hold on there! Wait a minute, Tom Swift! Bless my admission ticket,
don't go! I've got something important to tell you! Hold on!"

"Humph! I know who that is!" cried Tom, motioning to Eradicate to
cease trying to start the motor.

"Mr. Damon, of course," agreed Ned. "I wonder what he wants?"

"A ride, maybe," went on Tom. "If he does we've got to take the
Scooter instead of this one. That holds four. Well, we may as well
see what he wants."

He jumped lightly from his seat in the monoplane and was followed by
Ned. They saw coming toward them, from the direction of the house, a
stout man, who seemed very much excited. He was walking so fast that
he fairly waddled, and he was smiling at the lads, for he was one of
their best friends.

"Glad I caught you, Tom." he panted, for his haste had almost
deprived him of breath. "I've got something important to tell you. I
hurried over as soon as I heard about it."

"Well, you're just in time," commented Ned with a laugh. "In another
minute we'd have been up in the clouds."

"What is it, Mr. Damon?" asked Tom. "Have you got wind of a city of
diamonds, or has some one sent you a map telling where we can go to
pick up ten thousand dollar bills by the basket?"

"Neither one; Tom, neither one. It's something better than either of
those, and if you don't jump at the chance I'm mistaken in you,
that's all I've got to say. Come over here."

He turned a quick glance over his shoulder as he spoke and advanced
toward the two lads on tiptoe as though he feared some one would see
or hear him. Yet it was broad daylight, the place was the starting
ground for Tom's aeroplanes and save Eradicate there was no one
present except Mr. Damon, Ned and the young inventor himsel