“Why there’s somebody on the island!” he exclaimed.

“Somebody on the island?” echoed Zeb incredulously.

“Yes, or at least there’s a dwelling place.”

The boy pointed to a rude sort of shack built of logs and roofed with boughs, which stood on the edge of the cleared space.

“Great Methuselah!” ejaculated Zeb.  “Can someone have stolen a march on us?”

“I don’t know, but it looks queer, and see, there’s a shovel.  Somebody has been digging here.”

“But who could it be?” demanded Tom, mystified.

“Gosh!  Looks as if we’ve bin euchered after all,” grumbled Zeb.

The Wondership came to earth at the edge of the lifeless-looking, bare space.  They clambered out of the machine and stood on what was, undoubtedly, Rattlesnake Island, for every landmark on the map had been verified as they dropped.

They looked about them for a minute and then Zeb drew his revolver out of the holster and began idly twiddling the cylinder.

“I want ter make sure she’s in workin’ order,” he said with a grim comprehension of the lips, “before we do any investigating.”

CHAPTER XXXI.

THE ISLAND OF MYSTERY.

There was an air of oppression, hard to explain, about the island.  But they all felt it.  The boys were inclined to talk in whispers and even Dick Donovan’s usual lively spirits seemed daunted.  There was something about the blistered, barren look of the cleared space on the edge of which they had landed that gave them all an odd feeling of melancholy.

Zeb was the first to shake this off.

“Our first job,” he said, “is to find out who is on the island and what they’ve been doing.”

Here and there in the black, swampy-looking bare space, they could see where holes had been dug, but when they examined the spade, which Jack had seen from the Wondership as they descended, they found that it was rusty and had evidently not been used for a long time.

It was the same in the rude hut which they examined.  Some rusty utensils and a few ragged old garments were all that was inside.  The dust lay thick on the floor and a large squirrel leaped out of the roof as they entered.

“Well, whoever was on the island has moved on again,” declared Zeb.

“Or died,” said Jack in a low tone.

“Wa’al, what I say is,” observed Zeb, “ther sooner we git at that what-yer-may-call-um stuff and get away agin, the better it’ll be for all of us.  There’s suthin’ about this island I don’t like.”

The others agreed, all except the professor, who, on hands and knees, was examining some rocks with his magnifying glass.

“Where shall we make camp?” asked Dick.

“I don’t much fancy this side of the island, somehow,” said Jack, “but we could pitch the tents on that little plateau up there and be comfortable and have a good view up and down the river at the same time.”