“That is the place we want to explore first,” announced Mr. Perry as reference was made to this retreat in the check-up.

“I agree with you,” Bud declared.  “If the prisoner left any traces behind him at all, we’re likely to find them on that island in there.”

“Is there any way we can get in?” Hal inquired.  “Too bad we haven’t a small rowboat or canoe with us.”

“We’ll investigate and see what we can find in the way of a water passage into the interior,” Mr. Perry announced.

“That means a little more circumnavigating,” Bud inferred.

“Right you are,” said Cub.  “Me to the pilot house again.”

Accordingly he resumed his position at the wheel and the boat was put in motion again.  His father followed him and cautioned him against too much speed in such places.

Slowly the Catwhisker crept around the island-surrounded island until they discovered a passage somewhat wider and apparently deeper than others they had seen thus far in the outer rim.

“It looks as if we might get through there,” suggested Hal.  He and Bud had followed into the pilot house soon after Cub and his father repaired to that place.

“It does look a little that way,” replied Mr. Perry.

“We might creep in there slowly, and if we find the passage obstructed so as to block our way, we could back out,” Hal continued.

“We have some long fender poles,” Cub amended.  “We could feel our way with them and probably keep out of serious trouble.”

“All right, let’s make the attempt,” said Mr. Perry.  “I’d very much like to get in there with this boat.”

Cub started the engine and the Catwhisker began slowly to nose its way through the passage.  In a few minutes the little craft was alongside a ledge of rock that projected as a sort of forehead from the top of a perpendicular short front, and the pilot brought her to a full stop.

CHAPTER XI

The Deserted Camp

Both the inner island and the surrounding rim of elongated isles were covered with a thick growth of trees and bushes, a condition that caused Hal to exclaim: 

“I bet this is the place.”

“What makes you so certain of that?” inquired Mr. Perry, looking sharply at the boy.

“Because it’s an ideal place for a Crusoe to be hidden so that passing ships could not see him,” Hal replied.

“But might he not swim over to one of these surrounding islands and attract attention from there?”

“Yes, if there’s a place to get ashore after swimming across,” said Cub.

“There’s nothing but high steep banks all along here, so far as I can see,” Bud remarked.

“That’s a good line of observation,” was Mr. Perry’s commendation.  “Now, let’s explore this island and see if your points are well taken.”

Even the landing at which the boat now rested was not particularly attractive as such at first view because of a rather difficult climb between it and the main level of the island.  However, all the members of the band of “Crusoe hunters” were good climbers and they soon made their way up the stony steep to the surface land level.