Andy rolled to one side. As he did so he uttered a loud cry, and then, to the astonishment of the boys, he disappeared from sight as if the frozen earth had opened and swallowed him up. At the same time the bear, that was just about to cast himself down on the fallen hunter, seemed to drop down through some hole into the earth.
For an instant Jack and Mark looked at each other with fear in their eyes.
"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.