Frank was amazed at the cool nerve and effrontery of the wretch. For a moment the young inventor was silent.

Then he said:

“You have one of our men in captivity here. I want him.”

The chief shook his head sullenly.

“What?”

“Mebbe no.”

“Mebbe, yes!” cried Frank, angrily. “Come, I’ll blow you to perdition if you don’t give him up!”

“No can do dat.”

“Why?”

“White man killed!”

For a moment Frank reeled as if given a terrific blow. He turned ghastly pale. Then Gaston was dead.

“That is awful!” he thought.

But something in the Esquimau chief’s face caused him to start. He grasped the situation at once.

“You are lying!” he hissed, leaning over the rail. “Give him up, or I’ll kill you and all your cowardly crew!”

The Esquimau chief laughed scornfully, and gave a peculiar cry. In a moment the vicinity was thronged with armed natives.

Frank saw that the crisis had come. There was no use in dallying further.

He picked up a bomb brought him by Barney and hurled it fairly into the midst of the murderous horde.

In a flash there was a frightful explosion. Heaps of dead and dying Esquimaux lay upon the ground.

The survivors fled wildly. Frank leaped from the airship’s deck. He rushed into the nearest bough hut.

There was Gaston bound hand and foot.

“Thank God! you have come to save me!” cried the scientist. “You are none too soon!”

“But there is yet danger!” cried Frank. “Follow me quickly!”

To the airship they rushed. The Esquimaux were recovering and seemed ready to fight. But though he could have annihilated the whole gang, Frank did not wait for their attack.

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