"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, which had been hidden by clouds, emerged and shone with dazzling splendor on the ice fields. It almost blinded the men. As they ran on they heard a shout behind them. Turning, they saw Washington and the professor, each with a gun, following. They waited for the pair to come up. "How far away is the place?" asked Mr. Henderson. "We must be close to it now," said Bill. "Yes, there is the bear Andy killed," pointing to where the dead animal was stretched on the ice. "But where are the boys?" "And where is Andy?" asked Amos Henderson. Not knowing what had become of the hunter and the boys, the rescue party was puzzled. They looked on every side but saw no traces. The ground was so uneven that the professor suggested the hunter and boys might be lying wounded in a hollow, and screened from sight. "We must scatter and look for them," he said. Meanwhile the three in the ice cave had been looking about them. They saw what had brought them into the place. It was a big cavern hollowed out by nature in the frozen crystals, and leading to it was a smooth inclined plane of ice. "How are we going to get out?" asked Jack, after all three had taken a survey of the cavern. "Can't we walk up the place where we slid down?" asked Mark. Jack was already busy trying to climb up the slippery place. It was much harder than it seemed. The incline was a glare of ice, and Jack's first attempt sent him sliding back with considerable force to the cavern floor. "There's only one way to do it," said Andy. "You must take my hunting knife and cut steps in the slide. Then you will have some support for your feet." The boys saw this was good advice and followed it. But the ice was frozen almost as hard as stone, and after chipping and cutting away for half an hour they only had three niches.