order to be able to know just how his Butterfly was going to behave, with a passenger of Mr. Damon's weight, the young inventor placed a bag of sand on the extra seat.
The monoplane was then wheeled to the end of the starting ground. Tom took his place in the seat, and Mr. Jackson started the propeller. At first the engine failed to respond, but suddenly with a burst of smoke, and a spluttering of fire the cylinders began exploding. The hat of Mr. Damon, who was standing back of the machine, was blown off by the wind created by the propeller.
"Bless my gaiters!" he exclaimed, "I never thought it was as strong as that!"
"Let go!" cried Tom to Mr. Jackson and Eradicate, who were holding back the monoplane from gliding over the ground.
"All right," answered the engineer.
An instant later the explosions almost doubled, for Tom turned on more gasolene. Then, like some live thing, the Butterfly rushed across the starting ground. Faster and faster it went, until the young inventor, knowing that he had motion enough, tilted his planes to catch the wind.
Up he went from earth, like some graceful bird, higher and higher, and then, in a big spiral, he began ascending until he was five hundred feet in the air. Up there he traveled back and forth,
