starting the engine and using one
of their adjustable light bulbs, which they hung over the side of the
car. Yet the cold had become so intense, although it was a dry Arctic
cold, that the work went forward only by stages, the boys being forced to
stop and warm their hands from time to time at the camp fire.

When the new moon showed through the dark border of spruce trees and the
brilliant northern stars pierced the black sky, the young aviators were
ready for another trial. It was eight o'clock. This time they packed the
snow for a hundred yards in front of the chassis of the car, and then,
arranging their few blankets in the cockpit and refreshing themselves
with some newly-made hot tea, exhausted and nervous, they climbed aboard.
Putting on all their power and holding their runners steadily to the
packed snow, they again started the _Gitchie Manitou_.

While the runners were yet gliding over the evenly-packed snow drifts,
there came an ominous jar on the side of the repaired ski and Norman
instantly threw the planes upward. It was a chance for, if the car
settled again, the new runner would probably give away. In its gathering
momentum, the airship drifted snowward again while both boys gulped. Then
as if guiding itself, it sprang upward once more.

"It's all right!" shouted Roy, "but we had a close call. If we have to
come down again we'll never get up."

"When we land again," added Norman, his mouth dry, "it'll be in the gas
camp."

In a few minutes the airship was over the Athabasca River again, which
was now vaporless and white beneath them.

"It's cold, all right," was Roy's comment at this moment. "I think
there's ice on the river."

In spite of the increasing coldness, the _Gitchie Manitou_ made its way
without trouble toward the distant camp. There was no wind and, although
the boys computed the temperature outside at not less than twenty below
zero, the interior of the little cockpit soon became cozy enough. The
heating appliances had been connected with the dynamo and Norman at times
even complained of the heat. After the first hour of flight, both boys
began looking for the flare of the gas well. When this at last came in
sight, the car was headed directly for it. At that time both boys agreed
that the river beneath was covered with ice from shore to shore.

"Anyway," said Norman, as the gas well came into full view, "looks as if
Paul didn't succeed in capping the gusher to-day."

To warn their