"What happened?"

"There must have been an ice slide!"

It was Alice who asked the question, and Paul who answered it. Standing in the darkened ice cave, through the walls of which, however, some light filtered, the four looked anxiously at one another.

"It was the dancing that did it," declared Ruth, in a low voice. "It loosened the ice and it slid down."

"Perhaps not," said Paul, not wanting Alice blamed, for she had proposed the light-footed stepping about on the slippery floor of the cavern. "It might have slid down itself."

"Well, let's see what the situation is," proposed Russ. "We can't stay in here too long, for it's freezing cold."

"Yes, let's see if we can get out," added Paul.

"See if we can get out!" repeated Ruth. "Why, is there any danger that we can not?"

"Every danger in the world, I should say," spoke Russ, and there was a worried note in his voice. "I don't want to alarm you," he went on, "but the fact is that we are shut up in this ice cave."

"Oh, don't say that!" cried Ruth.

"Why shouldn't he—if it's true?" asked Alice. "Let's face the situation, whatever it is. Russ, will you see just how bad it is?"

Without speaking, the young moving picture operator went to the hole through which they had stooped to enter the cavern. In a moment he came back.

"It's closed tighter than a drum," he announced. "A lot of ice slid down from above and closed the entrance to the cave as if a door had been shoved across it. We can't get out!"

For a moment no one spoke, and then Paul asked, quietly:

"What are we going to do?"

"Have you a knife?" asked Russ.

"A knife? Yes, but what good is that?"

"We've got to cut our way out—that's all."

Ruth and Alice looked at each other. They began to understand what it meant.

"Someone from Elk Lodge may come for us—if we don't get back," murmured the younger girl, in what was almost a whisper.

"Yes, they may, but it's dangerous to wait," said Paul. "It is cold in here, and it isn't getting any warmer. It's like being locked in a refrigerator. We've got to keep in motion or we'll freeze."

"Then let's tackle that block of ice at the entrance," suggested Russ. "Get out your knife and we'll see if we can't cut a hole large enough to crawl through."

If you have tried to cut with a pocket knife even the small piece of ice which you get in your refrigerator, you can appreciate the task that confronted the two young men. A solid block of ice had slid down from some higher point, and had blocked the opening to the odd cavern. But the two were not daunted. They realized the necessity of getting out, and that within a short time. Though they were all warmly dressed, the air of the cavern was chilly, to say the least.

"Keep moving, girls!" called Russ to Ruth and Alice, as he and Paul chipped away at the ice. "This exercise will keep us warm; but you need to do something to keep your blood in circulation. Here, take my coat!" he called, as he arose from his knees, and tossed the garment to Ruth.

"I shall do nothing of the sort!" she answered, promptly. "You need it yourself."

"No, I don't," he replied, earnestly. "It only bothers me when I try to cut the ice. Please take it."

"But I can't get it on over my cloak."

"Yes, you can. Put it around your shoulders. I'll show you how." And he did it quickly, wrapping it warmly around her.

"Here, Alice, you take mine!" cried Paul, as he saw what his companion had done. "You need it more than I do, and I can't get at that ice with a big coat like this on."

In spite of her protests he put it about her, and the added warmth of the garments was comforting to the girls.

The boys, really, were better off without them, for they had much vigorous work before them, and in the narrow quarters the heavy coats only hampered them.

For it was an exceedingly narrow space in which they had to work. The fall of the mass of ice had crushed part of the opening into the cave, so that Russ and Paul had to crouch down and stoop in a most uncomfortable position in order to reach the block that had closed the doorway.

With their knives they hacked away at the frozen mass, sending the chips flying. Much of it went in their faces and soon their cheeks were glowing from the icy spray of splinters. Then, too, they had to stop every now and then to clear away the accumulated ice crystals that fell before the attack of their knives.

"Keep moving, girls," Paul urged Ruth and Alice. "Keep circling around or you'll surely freeze."

"Let'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 this through the translucent walls of the cave.

"Do you think they will come for us?" asked Ruth, in a low tone.

"Oh, yes, of course. If we don't get back by dark," responded Russ, as cheerfully as he could. "But we'll be out before then. Come on, Paul. Dig away!"

But it was very evident that they would not be out before dark. The ice block was thicker than Russ and Paul imagined.

"Please rest!" begged Alice, after a period of hard work by the two young men. "Please take a rest!"

"Can't afford a vacation," returned Russ, grimly.

But when he did halt for a moment, to get his breath, there came from outside the cave a sound that sent all their hearts to beating joyfully for it was the voice of some calling:

"Where are you? Where are you? Alice! Ruth!"

"Oh, it's daddy!" cried the girls together, and then Russ took up the refrain, shouting:

"We're in the cave! Get axes and chop us out! We've only got our knives!"

"We'll be with you in a moment!" said another voice, which they recognized as that of Mr. Macksey. "We'll have to go for a couple of axes!"

And then, as the hunter started back to Elk Lodge, Mr. DeVere, who remained outside the ice cave, explained through a crevice in the ice wall that made conversation possible how, becoming uneasy at the failure of his daughters to return, he had set out, in company with Mr. Macksey to look for them.

In their turn Ruth and Alice, with occasional words from Russ and Paul, told how they had become imprisoned.

"Are you hurt?" asked Mr. DeVere, anxiously.

"Not a bit of it, but we're awfully cold, Daddy," replied Alice.

"We must give the boys back their coats," said Ruth to her sister in a low tone. "They are not chopping now, and they'll freeze."

Russ and Paul did not want to accept their garments, but the girls were insistent, and made them don the heavy coats. Then the four walked rapidly around the cave to keep their blood in circulation.

"I wish Mr. Pertell would come and bring the camera," said Russ. "He could get a good moving picture of the rescue."

"Maybe he will," suggested Paul.

There was a little silence, and then Mr. DeVere called, from outside the cave;

"Here they come! Now you will soon be rescued! There's help enough to chop away the whole cave!"