“At this rate we will have to stay here several days,” said the old hunter, and there came an anxious note in his voice.  “I wish we could send word to some of the others.”

“Hark!  What was that?” asked Jack suddenly.

All listened.  There came a faint report, like that of a gun.

“It’s the professor, Washington, and the two farmers searching for us!” exclaimed Mark.  “They are firing their rifles.”

“That’s it!  They can’t find us because we are down in this hole,” said Andy.  “If I only had a cartridge now I could give an answer.”

There came another report.  This time there was no doubt that signal guns were being fired, for the shot sounded quite close.

Jack put his hand in his pocket.  His fingers touched something.

“Hurrah!” he cried.  “I have my revolver and there are four shots left!”

He passed it over to Andy, who shot twice at intervals of about a quarter of a minute.

“Where are you?” they heard a faint voice calling from somewhere above their heads.

In reply Andy fired the last shot.  It was responded to, and then, a few seconds later, a dark object loomed up at the opening at the top of the inclined plane.  The prisoners, looking up, recognized the professor.

“Hello, down there!” he shouted.

“Hello, up there!” answered Andy.

“We’ll get you out!” called down the inventor.  “How did you get there?  What do you need in order to come up here?”

“We slid down,” said the hunter in reply, “and we didn’t do it for fun either.  If you’re going to get us out you’ll need a long rope.”

The professor, sizing up the situation, sent Bill Jones back to the ship on the run to bring a long stout cable.  While this was coming there were questions and answers sent up and down the inclined shaft that told each of the two parties what had happened.  In a short time the rope was brought, and one end fastened to an iron bar thrust into the ice, while the other was thrown down to the prisoners.  With this as an aid and guide they were able to walk up the incline and soon were on the surface again.

“There, I forgot something!” exclaimed the old hunter as he emerged from the mouth of the shaft.

“What?” asked the professor.

“The polar bear,” was the answer.  “I think I’ll go back after him.  The skin may be valuable.”

“There are plenty more,” said the inventor.  “We have no time to go back after this one.  I must hurry to the ship.”

Pulling up the rope, and strapping their rifles on their backs, the party of rescued ones and rescuers began their march to the airship.  They decided to leave the bear Andy had first shot on the ice, and come back later for some steaks.

It was a bright day, and though it was very cold, being about twenty degrees below zero, there was no wind, which was a great relief.  The party marched on, with Andy in the lead.  He had reloaded his rifle with some ammunition the helpers had brought from the ship, and he was almost wishing he would meet another bear or two, now that he was ready for them.