main motor? You will see the
places marked where the oil is to go in. Ned, you help him. Here,
Abe, come over here and give me a hand. This wind makes the rudders
hard to twist."

The young inventor could not have chosen a better method of
relieving the fears of his friends than by giving them something to
do to take their minds off their own troubles. They hurried to the
tasks he had assigned to them, and, in a few minutes, there were no
more doubts expressed.

Not that the RED CLOUD was out of danger, Far from it. The storm was
increasing in violence, and the hailstones seemed to double in
number. Then, too, being forced upward as she was, the airship's bag
was pelted all the harder, for the speed of the craft, added to the
velocity of the falling chunks of hail, made them strike on the
surface of the ship with greater violence.

Tom was anxiously watching the barograph, to note their height. The
RED CLOUD was now about two and a half miles high, and slowly
mounting upward. The gas machine was working to its fullest
capacity, and the fact that they did not rise more quickly told Tom,
more plainly than words could have done, that there were several
additional leaks in the gas-bag.

"I'll take her up another thousand feet," he announced grimly.
"Then, if we're not above the storm it will be useless to go
higher."

"Why?" asked Ned, who had come back to stand beside his chum.

"Because we can't possibly get above the storm without tearing the
ship to pieces. I had rather descend."

"But won't that be just as bad?"

"Not necessarily. There are often storms in the upper regions which
do not get down to the surface of the earth, snow and hail storms
particularly. Hail, you know, is supposed to be formed by drops of
rain being hurled up and down in a sort of circular, spiral motion
through alternate strata of air--first freezing and then warm, which
accounts for the onion-like layers seen when a hailstone is cut in
half."

"That is right," broke in Mr. Parker, who was listening to the young
inventor. "By going down this hail storm may change into a harmless
rain storm. But, in spite of that fact, we are in a dangerous
climate, where we must expect all sorts of queer happenings."

"Nice, comfortable sort of a companion to have along on a gold-hunting
expedition, isn't He?" asked Tom of Ned, making a wry face
as Mr. Parker moved away. "But I haven't any time to think of that.
Say, this is getting fierce!"

We