orward. Several
of the beasts were limping.

"There ship!" cried the woman suddenly. The crew and owner of the
_Monarch_ glanced ahead. They saw, about a quarter of a mile in advance,
their airship, resting on an icy ledge.

"If we can only get there first!" cried the professor.

"You forget the leak in the gas bag," spoke up Andy. "That will have to
be mended before we can escape."

"With quick work we can do it!" exclaimed the inventor. "Hurry on,
Dirola!"

Dirola needed no urging. With fierce words she hurried on the dogs, her
whip sounding like a revolver as it snapped and cracked.

But fast as the escaping ones went, the pursuers seemed to come faster.
Now they were so close that they could be seen brandishing their spears,
bows and arrows. Their shouts, too, were borne forward on the cold wind.

At last the adventurers were at the side of the airship. Hastily they
dismounted from their sleds turning the dogs loose. The Esquimaux in
pursuit were about half a mile to the rear and would soon be upon them.

"Quick, Dirola! Into the ship with you!" called Andy. "We'll take you
with us if we go at all!"

"We must mend the tear first!" exclaimed the professor, scrambling up
the icy slope toward the cabin of the _Monarch_ in a fashion that would
have done credit to a much younger man. "Andy, you and the boys, with
Tom and Bill, hold the enemy at bay until Washington and I get the ship
in readiness for a start!"

"All right!" cried Andy, now in his element. "I'll make those Esquimaux
wish they had let us alone!"

Dirola had disappeared inside the cabin. In a few minutes the professor
and Washington were hard at work setting the machinery in motion.

First, after having seen that none of the apparatus was disarranged,
Amos Henderson started the gas generating machine. Next, leaving
Washington in charge of this and the engine room, the inventor prepared
a big patch with some cement on it. This he gave to Mark, who quickly
found the place where the old patch had come off the silk bag, and
covered the opening. Already the bag was beginning to swell with the
gas.

But now with loud yells the Esquimaux came rushing up. Leaping off their
sleds, they began throwing their spears and shooting their arrows.

CHAPTER XVIII

NORTHWARD ONCE MORE

"Repel boarders!" sung out Andy. "Where are the guns?"

"Here!" shouted Tom, handing out the rifles fully loaded.

The old hunter seized a weapon, as did Bill, Ja