"Want a race?" asked Mr. Hastings good-naturedly.

"Sure!" agreed Tom, and he shoved the timer ahead to produce quicker explosions.

The ARROW seemed to leap forward and for a moment was ahead of the CARLOPA, but with a motion of his hand to the spark lever Mr. Hastings also increased his speed. For a moment the two boats were on even terms and then the larger and newer one forged ahead. Tom had expected it, but he was a little disappointed.

"That's doing first rate," complimented Mr. Hastings as he passed them. "Better than I was ever able to make her do even when she was new, Tom."

This made the present owner of the ARROW feel somewhat consoled. He and Ned ran on for a few miles, the CARLOPA in the meanwhile disappearing from view around a bend. Then Tom and his chum turned around and made for the Swift dock.

"She certainly is a dandy!" declared Ned. "I wish I had one like it."

"Oh, I intend that you shall have plenty of rides in this," went on his friend. "When you get your vacation, you and dad and I are going on a tour," and he explained his plan, which, it is needless to say, met with Ned's hearty approval.

Just before going to bed, some hours later, Tom decided to go down to the dock to make sure he had shut off the gasoline cock leading from the tank of his boat to the motor. It was a calm, early summer night, with a new moon giving a little light, and the lad went down to the lake in his slippers. As he neared the boathouse he heard a noise.

"Water rat," he murmured, "or maybe muskrats. I must set some traps."

As Tom entered the boathouse he started back in alarm, for a bright light flashed up, almost in his eyes.