Down Lake Carlopa speeded the Arrow, those on board watching the banks slip past as the motor-boat rapidly cut through the water.

"What time do you think we ought to reach home, Tom?" asked Mr. Swift.

"Oh, about four o'clock, if we don't stop for lunch."

"Then we'll not stop," decided the inventor. "We'll eat what we have on board. I suppose you have some rations?" and he smiled, the first time since hearing the bad news.

"Oh, yes, Ned and I didn't eat everything on our camping trips," and Tom was glad to note that the fine weather which followed the storm was having a good effect on his father.

"We certainly had a good time," remarked Ned. "I don't know when I've enjoyed a vacation so."

"It's too bad it had to be cut short by this robbery," commented Mr. Swift

"Oh, well, my time would be up in a few days more," went on the young bank employee. "It's just as well to start back now."

Tom took the shortest route he knew, keeping in as close to shore as he dared, for now he was as anxious to get home as was his father. On and on speeded the Arrow, yet fast as it was, it seemed slow to Mr. Swift, who, like all nervous persons, always wanted to go wherever he desired to go instantly.

Tom headed his boat around a little point of land, and was urging the engine to the top notch of speed, for now he was on a clear course, with no danger from shoals or hidden rocks, when he saw, darting out from shore, a tiny craft which somehow seemed familiar to him. He recognized a peculiar put-putter of the motor.

"That's the Dot," he remarked in a low voice to Ned, "Miss Nestor's cousin's boat."

"Is she in it now?" asked Ned.

"Yes," answered Tom quickly.

"You've got good eyesight," remarked Ned dryly, "to tell a girl at that distance. It looks to me like a boy."

"No, it's Mary---I mean Miss Nestor," the youth quickly corrected himself, and a close observer would have noticed that he blushed a bit under his coat of tan.

Ned laughed, Tom blushed still more, and Mr. Swift, who was in a stern seat, glanced up quickly.

"It looks as if that boat wanted to hail us," the inventor remarked.

Tom was thinking the same thing, for, though he had changed his course slightly since sighting the Dot, the little craft was put over so as to meet him. Wondering what Miss Nestor could want, but being only too willing to have a chat with her, the young inventor shifted his helm. In a short time the two craft were within hailing distance.

"How do you do?" called Miss Nestor, as she slowed down her motor. "Don't you think I'm improving, Mr. Swift?"

"What's that? I---er---I beg your pardon, but I didn't catch that," exclaimed the aged inventor quickly, coming out of a sort of day-dream. "I beg your pardon." He thought she had addressed him.

Miss Nestor blushed and looked questioningly at Tom.

"My father," he explained as he introduced his parent. Ned needed none, having met Miss Nestor before. "Indeed you have improved very much," went on our hero. "You seem able to manage the boat all alone."

"Yes, I'm doing pretty well. Dick lets me take the Dot whenever I want to, and I thought I'd come out for a little trial run this morning. I'm getting ready for the races. I suppose you are going to enter them?" and she steered her boat alongside Tom's, who throttled down his powerful motor so as not to pass his friend.

"Races? I hadn't heard of them," he replied.

"Oh, indeed there are to be fine ones under the auspices of the Lanton Motor Club. Mr. Hastings, of whom you bought that boat, is going to enter his new Carlopa, and Dick has entered the Dot, in the baby class of course. But I'm going to run it, and that's why I'm practicing."

"I hope you win," remarked Tom. "I hadn't heard of the races, but I think I'll enter. I'm glad you told me. Do you want to race now?" and he laughed as he looked into the brown eyes of Mary Nestor.

"No, indeed, unless you give me a start of several miles."

They kept together for some little time longer, and then, as Tom knew his father would be restless at the slow speed, he told Miss Nestor the need of haste, and, advancing his timer, he soon left the Dot behind. The girl called a laughing good-by and urged him not to forget the races, which were to take place in about two weeks.

"I suppose Andy Foger will enter his boat," commented Ned.

"Naturally," agreed Tom. "It's a racer, and he'll probably think it can beat anything on the lake. But if he doesn't manage his motor differently, it won't."

The distance from Sandport to Shopton had been more than half covered at noon, when the travelers ate a lunch in the boat. Mr. Swift was looking anxiously ahead to catch the first glimpse of his dock and Tom was adjusting the machinery as finely as he dared to get out of it the maximum speed.

Ned Newton, who happened to be gazing aloft, wondering at the perfect beauty of the blue sky after the storm, uttered a sudden exclamation. Then he arose and pointed at some object in the air.

"Look!" be cried, "A balloon! It must have gone up from some fair."

Tom and his father looked upward. High in the air, almost over their heads, was an immense balloon. It was of the hot-air variety, such as performers use in which to make ascensions from fair grounds and circuses, and below it dangled a trapeze, upon which could be observed a man, only he looked more like a doll than a human being.

"I shouldn't like to be as high as that," remarked Ned.

"I would," answered Tom as he slowed down the engine the better to watch the balloon. "I'd like to go up in an airship, and I intend to some day."

"I believe he's going to jump!" suddenly exclaimed Ned after a few minutes. "He's going to do something, anyhow."

"Probably come down in a parachute," said Tom. "They generally do that."

"No! No!" cried Ned. "He isn't going to jump. Something has happened! The balloon is on fire! He'll be burned to death!"

Horror stricken, they all gazed aloft. From the mouth of the balloon there shot a tongue of fire, and it was followed by a cloud of black smoke. The big bag was getting smaller and seemed to be descending, while the man on the trapeze was hanging downward by his hands to get as far as possible away from the terrible heat.