, with long arms hanging.

"It's the wild man!" gasped Tom, while the three worthies on the beach
uttered a startled cry.

"It's ghosts, that's what it is," declared Sam Higgins shuddering.

"Nonsense. It's those kids. That's who it is," said Bill, but his
voice was rather shaky.

"I never heard anything human laugh like that," declared Eph. "Ugh! it
makes my blood run cold."

"Maybe we'd better go back," said Sam. "If we've got a right here I'd
just as soon land in the daylight."

"You're a fine pair of babies," growled Bill. "I'm sorry I brought you
along. Ghosts indeed--Wow! what was that?"

Another long ringing peal of laughter sounded through the night. It
reverberated against the steep walls of the canyon and was flung
mockingly from crag to crag. The boys felt their blood chill as they
heard it. There was something diabolical in the merriment of the wild
man who, they knew, was making the hideous sounds.

"I'm going back to the other island," declared Sam.

"If you move I'll knock your head off," said Masterson. "It's just a
trick of those kids to scare us, that's all it is."

CHAPTER XXXV.

TRIUMPH.

It was midnight. The moon rode high in a cloudless sky, and the camp
of the Boy Inventors, to all appearances, was wrapped in slumber.
Through the woods came three creeping, cautious figures. Each carried
a spade and a sack. They paused by the camp and looked about them.

Then, by the bright moonlight, they saw the bare plateau below. The
black barren where the adventurers had been working that afternoon.
Masterson was the first to see traces of digging. He seized Eph's arm
and pointed.

"That's the place," he said in a hoarse whisper. "See, they've been at
work there already."

"Tom Tiddler's ground," whispered Eph.

"I guess we'll get some of it, too," chuckled Sam, who had gotten over
his fright in a sudden greed at the thought of riches.

Silently, for they had sacks tied round their feet, the three
interlopers crept down the rocky slope toward the black barren. The
dark ground, thickly sown with mineral wealth, glittered in the
moonlight as if a frost had fallen on it and made it gleam
iridescently with millions of sparkling points of light.

As the trio stole down the slope, dark figures from the Boy Inventors'
camp followed them. Led by Zeb, they found hiding places and watched
operations as Masterson and his cronies began to dig. They wielded
their shovels frantically.

"And