that we will soon be
moving northward," spoke Mr. Parker, a little later. "I am anxious
to confirm my theory about the advance of the ice crust, I met a man
to-day who had just returned from the north of Alaska. He said that
a severe winter had already set in up there. So I am anxious to get
to the ice caves."

"So am I," added Tom, but it was for a different reason.

They were all up early the next morning, for there were several
things to look after before they started on the trip that might
bring much of danger to the adventurers. Under Tom's direction, more
gas was generated, and forced into the big bag. A last adjustment
was made of the planes, wing tips and rudders, and the motor was
given a try-out.

"I guess everything is all right," announced the young inventor.
"We'll take her out."

The RED CLOUD was wheeled from the big shed, and placed on the open
lot, where she would have room to rush across the ground to acquire
momentum enough to rise in the air. Tom, whenever it was practical,
always mounted this way, rather than by means of the lifting gas,
as, in the event of a wind, he would have better control of the
ship, while it was ascending into the upper currents of air, than
when it was rising like a balloon.

"All aboard!" cried the lad, as he looked to see that the course was
clear. Early as it was, there was quite a crowd on hand to witness
the flight, as there had been every day of late, for the population
of Seattle was curious regarding the big craft of the air.

"Let her go!" cried Ned Newton, enthusiastically.

Tom took his place in the steering-tower, or pilothouse, which was
forward of the main cabin. Ned was in the engine-room, ready to give
any assistance if needed. Mr. Damon, Mr. Parker and Abe Abercrombie
were in the main cabin, looking out of the windows at the rapidly
increasing throng.

"Here we go!" cried the young inventor, as he pulled the lever
starting the motor, There was a buzz and a hum. The powerful
propellers whirred around like blurs of light. Forward shot the
great airship over the ground, gathering speed at every revolution
of the blades.

Tom tilted the forward rudder to lift the ship. Suddenly it shot
over the heads of the crowd. There was a cheer and some applause.

"Off for the frozen north!" cried Ned, waving his cap.

Tom shifted the rudder, to change the course of the airship. Mr.
Damon was gazing on the crowd below.

"Tom! Tom!" he cried suddenly. "There'