The lad did not tell his father of the adventure with Morse, but he
related the occurrence to Mr. Sharp.

"I'd like to get hold of that scoundrel, and the others in the gang!"
exclaimed the balloonist. "I'd take him up in the airship, and drop
him down into the lake. He's a bad man. So are the others. Wonder what
they -want around here?"

"That's what's puzzling me," admitted Tom. "I hope dad doesn't hear
about them or he will be sure to worry; and maybe it will interfere
with his new ideas."

"He hasn't told you yet what he's engaged in inventing; has he?"

"No, and I don't like to ask him. He said the other day, though, that
it would rival our airship, but in a different way."

"I wonder what be meant?"

"It's hard to say. But I don't believe he can invent anything that
will go ahead of our craft, even if he is my own father, and the best
one in the world," said Tom, half jokingly. "Well, I got the bolts,
now let's get to work. I'm anxious for a trial trip."

"No more than I am. I want to see if my ideas will work out in
practice as well as they do in theory."

For a week or more Tom and Mr. Sharp labored on the airship, with Mr.
Jackson to help them. The motor, with its twenty cylinders, was
installed, and the big aluminum holder fastened to the frame of the