"I told you I'd get square with you, and I've done it," and then Andy's footsteps died away, while a mocking laugh floated back to Tom. What was Andy's revenge?

Chapter IX The Whizzer Flies

For a moment, Tom gazed after the fleeting figure of the cowardly bully. He was half-minded to give pursuit, and then, realizing that he could find Andy later if he wanted him, the young inventor decided his best plan would be to see what damage had been done. For that damage would follow Andy's secret visit to the shop, Tom was certain.

Nor was his surmise wrong. Stepping into the building, the lad switched on the lights, and he could not repress an exclamation of chagrin as he looked toward his trim little monoplane, the Butterfly.

Now it was a Butterfly with broken wings, for Andy had slashed the canvas of the planes in a score of places.

"The scoundrel!" growled Tom. "I'll make him suffer for this! He's all but ruined my aeroplane."

Tom walked around his pet machine. As he came in front, and saw the propeller, he gave another exclamation. The fine wooden blades of several layers, gracefully curved, which had cost him so much in time and labor to build up, and then fashion to the right shape, had been hacked, and cut with an axe. The propeller was useless!

"More of Andy's work," murmured Tom. "This is about the worst yet!"

There came over him a feeling of great despondency, which was succeeded by a justifiable rage. He wanted to take after the bully, and give him a merciless beating. Then a calmer mood came over Tom.