Night came, and the hostile natives showed no sign of returning.

A strict watch was kept until morning, but nothing out of the ordinary happened.

In the meantime Captain Sumner and Bob examined the map with great care and also read and reread the papers Ruel Gross had left behind him.

"Let us go on another tour of exploration," said the captain, on the following day. "If those natives come back Bok can fire a gun to warn us."

The boy readily agreed and they set off without delay.

Once under the dead cedar tree they looked around them curiously.

A short distance further inland they saw a hollow, which had evidently at one time been a camp.

Tin cans were strewn around, along with a number of fish and animal bones.

"I wonder if father and Ruel Gross once encamped here?" thought Bob.

Hardly had the idea occurred to him than Captain Sumner set up a shout.

He was pointing to a post set up in the ice. To the top of the post was attached a rude sign, which read:

"To the Svlachkys' Camp—One Mile."

"Hurrah! here's a discovery!" cried Bob. "Shall we go on?"

"Yes; but let us advance with extreme caution. These Svlachkys may be very bad people."

"Undoubtedly there are, or they wouldn't keep my father a prisoner," rejoined Bob.

"That signpost must be the work of Ruel Gross," went on the captain. "The savages haven't dared to touch it, thinking there was something supernatural attached to it—something to injure them."

On went the captain and Bob, down one hill of ice and up another. It was extremely cold, but neither minded that.

At last they reached a portion of the island that was very uneven. Great chasms yawned to the right and left of them. It was with difficulty that they pushed forward.

But they were bound to go on, and go the............