nd silent in the shop. Suddenly the
light flashed up brighter than before, and the young inventor caught
sight of a man walking around the new aeroplane, examining it
carefully. He carried, as Tom could see, a large-sized electric
flash-lamp, with a brilliant tungsten filament, which gave a powerful
light.

As the youth watched, he saw the intruder place the light on a bench,
in such a position that the rays fell full upon the Humming-Bird. Then,
adjusting the spring switch so that the light would continue to glow,
the man stepped back and drew something from an inner pocket.

"I wonder what he's up to?" mused Tom. "I wish Eradicate and Mr.
Jackson would hurry back. Who can that fellow be, I wonder? I've never
seen him before, as far as I know. I thought sure it was going to turn
out to be Andy Foger!"

Tom turned around to look into the dark yard surrounding the shed. He
was anxious to hear the approach of his two allies, but there was no
sound of their footsteps.

As he turned back to watch the man he could not repress a cry of alarm,
for what the intruder had drawn from his pocket was a small hatchet,
and he was advancing with it toward the Humming-Bird!

"He's going to destroy my aeroplane!" gasped Tom, and he raised his
revolver to fire.

He did not intend to shoot at the man, but only to fire to scare him,
and thus hasten the coming of Mr. Jackson and the colored man. But
there was no need of this, for an instant later the two came running up
silently, Eradicate with a big club.

"Whar am he?" he asked in a hoarse whisper. "Let me git at him, Massa
Tom!"

"Hush!" exclaimed the young inventor. "We have no time to lose! He's in
there, getting ready to chop my aeroplane to bits! Go to the back door,
Rad, and if he tries to come out don't let him get away."

"I won't!" declared the colored man emphatically, and he shook his club
suggestively.

"Come on! We'll go in the front door," whispered Tom to the engineer.
"I have the key. We'll catch him red-handed, and hand him over to the
police."

Waiting a few seconds, to enable Eradicate to get to his place, Tom and
the engineer stole softly toward the big double doors. Every moment the
youth expected to hear the crash of the hatchet on his prize machine.
He shivered in anticipation, but the blows did not fall.

Tom pushed open the door and stepped inside, followed by Mr. Jackson.
As they did so they saw the man standing in front of the Humming-Bird.
He a