s.

"What has happened?" inquired Mark, in an awestruck voice.

"I don't know," answered Jack. "But look! there are spots of blood over
there. That is where the bear was!"

The boys ran forward. As they did so their feet seemed to slip from
under them. Down and down they felt themselves going. Faster and faster
they slipped. They gazed with frightened eyes about them and saw they
were on some giant slide of ice, that led into unknown regions.

"Where are we going?" gasped Mark.

"I don't know!" yelled back Jack. "At any rate we're getting a good
coast!" He could joke even in the face of danger.

With a jolt the two boys came to the end of their sudden journey. For a
moment they were so startled and shaken up that they could hardly see.
Then, as their senses came back, they gazed around.

There were white glistening walls of ice on every side. Above glittered
a tiny patch of light, showing where the blue sky was.

"Where are we?" asked Mark.

"You're with me an' the bear!" exclaimed a voice.

The boys started. They saw, lying near them, old Andy. At his feet was
the polar bear, dead, with the hunter's knife sticking in his heart.

"And what place is this?" asked Jack.

"It appears to me like a big ice cave," answered the hunter.

"Yes, and we're lost in it," spoke up Jack, and gave something of a
shudder.

"That's right, my boy," answered Andy Sudds.

CHAPTER XI

ATTACKED BY SEA LIONS

Frightened and alarmed at the unusual sight of an enraged polar bear
rushing in their direction, Bill and Tom had turned and fled at the
first appearance of danger. They were not cowards, and would probably
have faced a mad bull, but that was something they were used to, while a
bear was something new.

So they raced back over the ice toward the place where the disabled
airship rested.

"Quick!" yelled Bill.

"They'll all be killed!" cried Tom.

"Who?" asked the professor, dropping his tools.

Rapidly the two helpers told what had occurred, and how they had left
Andy and the boys as the bear was rushing at them, the hunter having no
more cartridges in his gun.

"Take two rifles from the chest!" exclaimed the inventor. "Washington
and I will follow as soon as we get our furs on! Hurry now!"

Tom and Bill needed no second bidding. Seeing that the magazines of the
rifles they took were filled, they hastened again over the ice and snow
in the direction of Sudds and the boys. As they hustled along, the sun