's dance," suggested Alice.

"Oh, how can you think of such a thing!" cried Ruth, "when it was that
which caused all the trouble."

"I'm not going to believe that!" declared Alice, firmly. "And it isn't
such a terrible thing to think of, at all. It will keep us warm, and
keep up our spirits."

And then she broke into a little one-step dance, whistling her own
accompaniment. Surely it was a strange proceeding, and yet it came
natural to Alice. The young men, too, took heart at her manner of
accepting the situation, and chopped away harder than ever at the ice
barrier.

"Think we'll make it?" asked Paul of Russ, in a low voice, when they had
been working for some time.

"We've got to make it," answered the other. "We've just got to get the
girls out."

"Of course," was the brief reply, as if that was all there was to it.

And yet, in their hearts, Russ and Paul felt a nameless fear. Ice, which
melts so easily under the warm and gentle influence of the sun, is
exceedingly hard when it is maintained at a low temperature, and truly
it was sufficiently cold in the cave.

Now and then the boys stopped to clear away the accumulation of ice
splinters, and to note how they were progressing. Yet they could hardly
tell, for they did not know how thick was the chunk of ice that covered
the cave opening. The edges of the opening itself were several feet in
thickness, and if this hole was completely filled it would mean many
hours of work with the pitifully inadequate tools at their disposal.

"How are we coming on?" asked Paul.

Russ looked back at the girls who, in one corner of the cave, were
pacing up and down to drive away the deadly cold.

"Not very well," he returned, in a low voice. "Don't talk--let's work."

He did not like to think of what might happen.

Desperately they labored, eating their way into the heart of the ice.
The splinters fell on their warm bodies, for they were perspiring now,
and there the frosty particles melted, wetting their garments through.

Suddenly Paul uttered a cry as he dug his knife savagely into the
barrier.

"What's the matter--cut yourself?" asked Russ.

"No," was the low-voiced reply. "But I've broken the big blade of my
knife. Now I'll have to use the smaller one."

It was a serious thing, for it meant a big decrease in the amount of ice
Paul could chop. But opening the small blade of the knife he kept
doggedly at the task.

It was growing darker now. They could observe