emingly torn
from a garment made of that material.

"There _is_ somebody else on the island!" gasped Jack, looking round
with white cheeks.

He clutched his rifle firmly. Looking about him he half expected to
see some wild face peering at him out of parted bushes. But nothing of
the sort happened. Feeling very uncomfortable, Jack came away from
the place and made his way back to camp.

This time he made up his mind to confide in Zeb. The prospector was as
mystified as Jack over the events of the night and the incident of the
rabbit trap. But he was unable to throw any light on the affair.

"It might be an Indian," he said, "or----"

"It might be the man that built that hut and left the shovel sticking
in that barren place down yonder," said Jack.

"In that case, wouldn't he be livin' in ther hut instead of snoopin'
round the island?" asked Zeb.

This view seemed to be incontrovertible. At noon the professor, who
had been scouting over the island looking for specimens which might
give him some clue as to the mineral deposits they had come in search
of, arrived in camp breathless and indignant.

"A joke's a joke," he said to the boys, "but this is going too far."

"What's the matter, professor?" asked Dick.

"Yes, what's happened?" asked Tom, who saw that the man of science
was really angry, and for some reason blamed them for whatever had
irritated him.

"As if you didn't know," declared the professor. "I set my bag of
specimens down on a rock while I went to investigate a
peculiar-looking formation."

"Well?" said Jack.

"Well, I heard a soft footstep and the crackling of some twigs. I
looked round and my bag of specimens had gone. Now which of you boys
played that foolish joke on me?"

"I'll give you my word we know nothing about it, professor," declared
Tom. "Dick and I have been working all the morning unpacking stuff
from the Wondership."

The professor looked at them incredulously.

"That's right," struck in Zeb, "they haven't been out of my sight."

"But--but," stammered the professor, "my dear sir, that bag of
specimens didn't walk off, you know. Besides," he added, "I heard a
human footfall distinctly."

"It may not have been the boys, though," spoke up Jack seriously.

"Indeed, who else then?" inquired the professor stiffly.

"An unwelcome neighbor," replied Jack. "We are not alone on this
island."

"Not alone? What do you mean?" demanded the professor in thunderstruck
tones.

"Ju