"Now father and I will go home. He told me how it would be, if he came down here; but at least we won the big prize, thanks to you, and money means so much to us now!"

The day was not over yet for the Go-Aheads and the Busters, although the races were finished. Somehow the news was spread among the campers on Gannet Island and Green Knoll that there was to be a "grand treat" at the ice-cream tables, and they gathered "like eagles to the kill,"

Frankie poetically declared.

The waiter brought heaping dishes of cream, there were nice cakes, and Tubby's unctuous smile at one end of the table radiated cheer. They were all very jolly and n.o.body asked who was to pay the piper until the waiter gravely brought Dave Shepard the check and a slip of paper.

"Hi! did _I_ order this feed?" demanded Dave, startled by the size of the check.

"I was ordered to give the check to you--and the paper," quoth the waiter, calmly.

"Gee, Dave! somebody's stung you!" croaked Tubby, with his mouth still full.

Dave unfolded the paper slowly, and read in his own handwriting: "I bet an ice-cream treat all around to the Go-Ahead girls that your curiosity would not permit you to leave this alone."

"You don't deny your own handwriting; do you, sir?" queried the waiter, with a perfectly grave face. "I served the company on that order, Mr.

Shepard."

"That Wyn Mallory! She got me!" groaned Dave, and paid up like a man.

"But what's the use of trying to put a joke over on those girls?" he said to Tubby afterward. "They're always turning the tables on a fellow."

"Very good table, too--very good table," agreed Tubby, smacking his lips. "But you're so reckless with your promises, Dave."

Mr. Lavine's man took the _Happy Day_ and the canoes back to camp, while the whole party of young folk piled aboard the larger _Sissy_. They had a fine time sailing down the lake and reached the Cave-in-the-Wood Camp at late supper time.

There was still light enough on the water for the voyagers to see a boat rocking on the waves in the little cove where Polly Jarley had first been introduced to the two canoe clubs.

"And that's Polly and her father there now," said Dave, quickly.

"Yes. It's the _Coquette_," agreed Wyn.

"What are they doing in there?" asked Frankie. "See! he is standing up and gesticulating--not to us. He's talking to Polly."

"That is the place where he had the misfortune to lose Dr. Shelton's motor boat last winter," said Wyn. "Don't you remember?"

"You see," Dave cried, "he is showing her the place where the limb fell again--and the direction the boat must have taken in the fog."

"A lot _he_ knows where it went," said Tubby, scornfully. "He was swept overboard, and as far as he knows the _Bright Eyes_ might have gone right up into the air!"

"But it didn't explode, you see, nor did it have wings," laughed Wynifred. "So it took no aerial voyage--we may be sure of that. I'd give anything to find where it sank."

"So would I, Wyn," cried Dave. "If we could locate the sunken boat, Mr.

Jarley could easily prove he had neither stolen it nor the silver images."

"I'd give something handsome to have the mystery explained, myself,"

said Mr. Lavine, suddenly.

"What would you give, Father?" asked his daughter.

"I'll tell you," he replied, smiling. "I understand both of your clubs--the Go-Aheads and the Busters--are anxious to really _own_ a motor boat. Frank Dumont, here, tells me he has got to go home with the _Happy Day_ to-morrow, as his vacation is ended.

"Now, I'll make you boys and girls an offer," pursued Mr. Lavine, more earnestly. "You'll hunt in packs, anyway--the boys together and the girls together. If the girls find the sunken boat I'll present them with a motor boat as good as the _Happy Day_; and if the boys have the luck, then the boat shall belong to the Busters. What say?"

"We say 'Thanks!'" cried Dave, instantly.

"_We_ think it is very handsome of you, sir," declared Wyn, coming over to the gentleman and taking his hand. "And I know why you do it, sir--so I thank you twice. If poor Mr. Jarley could be absolved of Dr.

Shelton's accusation, it would help a whole lot."

"Humph!" muttered Mr. Lavine, "I heard Shelton going on about Jarley myself to-day, and it made me ashamed--I'm free to own it. I never _did_ think John as bad as all that!"

"It sounds different when you hear somebody else say it," whispered Dave in Wynifred's ear.

Mr. Lavine's proposal, however, met with enthusiastic favor on the part of both clubs. A motor boat would be just the finest thing to own! Both boys and girls determined to find the lost _Bright Eyes_ before the season was out.

CHAPTER XXI

THE WAY OF THE WIND

"Did you know," said Professor Skillings, visiting Camp Green Knoll with the Busters several days later, "that there are several thousand Poles in the Wintinooski Valley?"

"You surprise me," remarked Mrs. Havel.

"Fine things to grow beans on, Professor," declared Dave, coming up with a br.i.m.m.i.n.g bucket of water from the spring.

"Not the right kind of poles, my boy--not the right kind of poles," said the professor, smiling gently, and offering Mrs. Havel a cocoanut-cup of the sparkling water. "You see what a misunderstanding of terms will do,"

the professor added, in his argumentative way. "A little knowledge--especially a little scientific knowledge--is a dangerous thing."

"You are right, Professor," cried Tubby, who was within hearing distance. "Did you hear about what Dr. Mackenzie's servant girl did?"

"Dr. Mackenzie is very erudite," commented the professor, dreamily.

"That's right. Anyhow, the girl heard a lot of talk about bugs, and grubs, and germs, and the like--and it proves just what Professor Skillings says about the danger of knowing a little science."

"How's that, Tubby?" queried one of the interested young folk.

"Why, one day the doctor's wife asked this servant for a gla.s.s of water, and the girl brought it.

"'It has a very peculiar taste, Mary,' said Mrs. Mackenzie.

"'Sure, ma'am, it's all right, ma'am. There ain't a germ in it, for I ran it through the colander before I brought it to you, ma'am!' says Mary. Oh, Mary had picked up some scientific notions, all right, all right!"

"I believe there would be more breeze up on Windmill Farm," observed Wynifred Mallory.

"Wish I was up there, then," growled Tubby, who had quite collapsed after telling his joke.