the auto
started, "and good luck to you!"

"We'll try to do a good turn some day to make up," shouted Pee-wee.

CHAPTER IX

THE MYSTERY

"What I don't understand," said Tom, in his dull way, "is how if that
fellow was drowned or killed that night, he managed to get back to this
boat again--that's what gets me."

"What?" said Roy.

"What are you talking about?" chimed in Pee-wee.

They were sitting in the little cabin of the _Good Turn_ eating rice
cakes, about an hour after the launching. The boat rocked gently at its
moorings, the stars glittered in the wide expanse of water, the tiny
lights in the neighboring village kept them cheery company as they
chatted there in the lonesome night with the hills frowning down upon
them. It was very quiet and this, no less than the joyous sense of
possession of this cosy home, kept them up, notwithstanding their
strenuous two days of labor.

"Just what I said," said Tom. "See that board you fixed the oil stove
on? I believe that was part of that skiff. You can see the letters
N-Y-M-P-H even under the paint. That strip was in the boat all the time.
How did it get here? That's what _I'd_ like to know."

Roy laid down his "flopper" and examined the board carefully, the
excited Pee-wee joining him. It was evidently the upper strip of the
side planking from a rowboat and at one end, under the diluted paint
which they had here used, could be dimly traced the former name of the
launch.

"What-do-you-know-about-that?" ejaculated Roy.

"It's a regular mystery," said Pee-wee; "that's one thing I like, a
mystery."

"If that's a part of this boat's skiff," said Tom, "then it proves two
things. It proves that the boat was damaged--no fellow could pull a
plank from it like that; and it proves that that fellow came back to the
launch. It proves that he was injured, too. That man said he could swim.
Then why should he bring this board back with him unless it was to help
him keep afloat?"

"He wouldn't need to drag it aboard," said Roy.

"Now you spoil it all," put in Pee-wee.

"I don't know anything about that," said Tom, "but that board didn't
drift back and climb in by itself. It must have been here all the time.
I suppose the other fellow--the one they found drowned--_might_ have got
it here, some way," he added.

"Not likely," said Roy. "If he'd managed to get back to the launch with
the board, he wouldn't have jumped overboard again just to get drowned.
He'd hav