The young inventor went back into the house after carefully locking the boat compartment and detaching from the engine an electrical device, without which the motor in the arrow could not be started.

“That will prevent them from running away with my boat, anyhow,” decided Tom.  “And I’ll tell Garret Jackson to keep a sharp watch to-night.”  Jackson was the engineer at Mr. Swift’s workshop.

Tom told his father of the happening and Mr. Swift was properly indignant.  He wanted to go at once to see Mr. Foger and complain of Andy’s act, but Tom counseled waiting.

“I’ll attend to Andy myself,” said the young inventor.  “He’s getting desperate, I guess, or he wouldn’t try to set the place on fire.  But wait until I show him these keys.”

Bright and early the next morning the owner of the motor-boat was down to the dock inspecting it.  The engineer, who had been on watch part of the night, reported that there had been no disturbance, and Tom found everything all right.  “I wonder if I’d better go over and accuse Andy now or wait until I see him and spring this evidence on him?” thought our hero.  Then he decided it would be better to wait.  He took the arrow out after breakfast, his father going on a short spin with him.

“But I must go back now and work on my gyroscope invention,” said Mr. Swift when about two hours had been spent on the lake.  “I am making good progress with it.”

“You need a vacation,” decided Tom, “I’ll be ready to take you and Ned in about two weeks.  He will have two weeks off then and, we’ll have some glorious times together.”

That afternoon Tom put some new style spark plugs in the cylinders of his motor and found that he had considerably increased the revolutions of the engine, due to a better explosion being obtained.  He also made some minor adjustments and the next day he went out alone for a long run.

Heading up the lake, Tom was soon in sight of a popular excursion resort that was frequently visited by church and Sunday-school organizations in the vicinity of Shopton.  The lad saw a number of rowing craft and a small motor-boat circling around opposite the resort and remarked:  “There must be a picnic at the grove to-day.  Guess I’ll run up and take a look.”

The lad was soon in the midst of quite a flotilla of rowboats, most of them manned by pretty girls or in charge of boys who were giving sisters (their own or some other chap’s) a trip on the water.  Tom throttled his boat down to slow speed and looked with pleasure on the pretty scene.  His boat attracted considerable attention, for motor craft were not numerous on Lake Carlopa.

As our hero passed a boat, containing three very pretty young ladies, Tom heard one of them exclaim: 

“There he is now!  That’s Tom Swift.”

Something in the tones of the voice attracted his attention.  He turned and saw a brown-eyed girl smiling at him.  She bowed and asked, blushing the while: