"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?" e.j.a.c.u.l.a.t.ed 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 have managed to stay aboard."

There was silence for a few minutes while Roy drummed on the plank with his fingers and Pee-wee could hardly repress his excitement at the thought that they were on the track of a real adventure. Tom Slade had "gone and done it again." He was always surprising them by his stolid announcement of some discovery which opened up delectable possibilities.

And smile as he would (especially in view of Pee-wee's exuberance), Roy could not but see that here was something of very grave significance.

"That's what I meant," drawled Tom, "when I told her that we could _try_--to find her brother."

This was a knockout blow.

"This trip of ours is going to be just like a book," prophesied Pee-wee, excitedly; "there's a--there's a--long lost brother, and--and--a deep mystery!"

"Sure," said Roy. "We'll have to change our names; I'll be Roy Rescue, you be Pee-wee Pinkerton, the boy sleuth, and Tom'll be Tom Trustful.

What d'you say, Tom?"

Tom made no answer and for all Roy's joking, he was deeply interested.

Like most important clues, the discovery was but a little thing, yet it could not be accounted for except on the theory that Harry Stanton had somehow gotten back to the launch after the accident, whatever the accident was. It meant just that--nothing less and nothing more; though, indeed, it did mean more to Pee-wee and as he slept that night, in the gently rocking boat, he dreamed that he had vowed a solemn vow to Mr.

Stanton's daughter to "find her brother or perish in the attempt." He carried a brace of pistols, and sailing forth with his trusty chums, he landed in the island of Madagascar, to which Harry Stanton had been carried, bound hand and foot, in an aeroplane. The three, undaunted, then built a Zeppelin and sailed up to the summit of a dizzy crag where they rescued the kidnapped youth and on reaching home, Mr. Stanton gave them a sea-going yacht and a million dollars each for pocket money.

When he awoke from this thrilling experience he found that the _Good Turn_ was chugging leisurely up the river in the broad daylight.

The boat behaved very well, indeed. She leaked a little from the strain of launching, but the engine pumped the water out faster than it came in. All day long they lolled in the c.o.c.kpit or on the cabin roof, taking turns at the steering. Roy, who best understood gas engines, attended to the motor, but it needed very little attention except that it missed on high speed, so he humored it and they ambled along at "sumpty-sump miles an hour," as Roy said, "but what care we," he added, "as long as she goes." They anch.o.r.ed for several hours in the middle of the day and fished, and had a mess of fresh perch for luncheon.

Naturally, the topic of chief interest was the possibility that Harry Stanton was living, but the clue which appeared to indicate that much suggested nothing further, and the question of why he did not return home, if he were indeed alive was a puzzling one.

"His sister said he had been to Costa Rica, and was fond of traveling,"

suggested Tom. "Maybe his parents objected to his going away from home so he went this way--as long as the chance came to him--and let them think he was drowned."

Roy, sitting on the cabin roof with his knees drawn up, shook his head.

"Or maybe he left the boat again and tried to swim to sh.o.r.e to go home, and didn't make it," he added.

"That's possible," said Tom, "but then they'd probably have found his body."

"We aren't sure he's alive," Roy said thoughtfully, "but it means a whole lot not to be sure that he's dead."

"Maybe he was made away with by someone who wanted the boat," said Pee-wee. "Maybe a convict from the prison killed him--you never can tell. Jiminys, it's a mystery, sure."

"You bet it is," said Roy. "The plot grows thicker. If Sir Guy Weatherby were only here, or Detective Darewell--or some of those story-book ginks they----"

"They probably wouldn't have noticed the plank from the skiff,"

suggested Pee-wee.

Roy laughed and then fell to thinking. "Gee, it would be great if we could find him!" he said.

And there the puzzling matter ended, for the time being; but the _Good Turn_ took on a new interest because of the mystery with which it was a.s.sociated and Pee-wee was continually edifying his companions with startling and often grewsome theories as to the fate or present whereabouts of Harry Stanton, until--until that thing happened which turned all their thoughts from this puzzle and proved that bad turns as well as good ones have the boomerang quality of returning upon their author.

It was the third afternoon of their cruise, or their "flop" as Roy called it, for they had flopped along rather than cruised, and the _Good Turn's_ course would have indicated, as he remarked, a fit of the blind staggers. They had paused to fish and to bathe; they had thrown together a makeshift aquaplane from the pieces of an old float which they had found, and had ridden gayly upon it; and their course had been so leisurely and rambling that they had not yet reached Poughkeepsie, when all of a sudden the engine stopped.

Roy went through the usual course of procedure to start it up, but without result. There was not a kick left in it. Silently he unscrewed the cap on the deck, pushed a stick into the tank and lifted it out--dry.

"Boys," said he, solemnly, "there is not a drop of gasoline in the tank.

The engine must have used it all up. Probably it has been using it all the time----"

"You make me sick," said Pee-wee.

"I have known engines to do that before."

"Didn't I tell you to get gasoline in Newburgh?" demanded Pee-wee.

"You did, Sir Walter, and would that we had taken your advice; but I trusted the engine and it has evidently been using the gasoline while our backs were turned. _We_ should worry! You don't suppose it would run on witch hazel, do you?"

"Didn't I tell----" began Pee-wee.

"If we could only reduce friend Walter to a liquid," said Roy. "I think we could get started all right--he's so explosive."

"Bright boy," said Tom.

"Oh, I'm a regular feller, I am," said Roy. "I knew that engine would stop when there wasn't any more gasoline--I just felt it in my bones.

But what care we!

'Oh, we are merry mountaineers, And have no carking cares or fears-- Or gasoline.'

Get out the oars, scouts!"

So they got out the oars and with the aid of these and a paddle succeeded in making the sh.o.r.e where they tied up to the dilapidated remnants of what had once been a float.

"There must be a village in the neighborhood," said Tom, "or there wouldn't be a float here."

"Sherlock Holmes Slade is at it again," said Roy. It would have been a pretty serious accident that Roy wouldn't have taken gayly. "Pee-wee, you're appointed a committee to look after the boat while Toma.s.so and I go in search of adventure--and gasoline. There must be a road up there somewhere and if there's a road I dare say we can find a garage--maybe even a village. Get things ready for supper, Pee-wee, and when we get back I'll make a Silver Fox omelet for good luck."

The spot where they had made a landing was at the foot of precipitous hills between which and the sh.o.r.e ran the railroad tracks. Tom and Roy, carrying a couple of gasoline cans, started along a road which led around the lower reaches of one of these hills. As Pee-wee stood upon the cabin watching them, the swinging cans were brightened by the rays of the declining sun, and there was a chill in the air as the familiar grayness fell upon the heights, bringing to the boy that sense of loneliness which he had felt before.