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."