d not take me out of the United States
without official documents, and they would have been forged ones, for
they intended trumping up a criminal charge against me, the political
one not being strong enough to allow them to extradite me."

"Well I'm glad we got you," said Tom heartily. "We will soon be ready
to start for Siberia."

"In this kind of a craft?"

"Yes, only much larger. You'll like it. I only hope my air glider
works."

By putting on speed, Tom was able to reach Shopton before midnight, and
there was quite an informal celebration in the Swift homestead over the
rescue of the exile. The detective, for whom there was no further need,
was paid off, and Mr. Petrofsky was made a member of the household.

"You'd better stay here until we are ready to start," Tom said, "and
then we can keep an eye on you. We need you to show us as nearly as
possible where the platinum field is."

"All right," agreed the Russian with a laugh. "I'm sure I'll do all I
can for you, and you are certainly treating me very nicely after what I
suffered from my captors."

Tom resumed work on his air glider the next day, and he had an
additional helper, for Mr. Petrofsky proved to be a good mechanic.

In brief, the air glider was like an aeroplane save that it had no
motor. It was raised by a strong wind blowing against transverse
planes, and once aloft was held there by the force of the air currents,
just like a box kite is kept up. To make it progress either with or
against the wind, there were horizontal and vertical rudders, and
sliding weights, by which the equilibrium could be shifted so as to
raise or lower it. While it could not exactly move directly against the
wind it could progress in a direction contrary to which the gale was
blowing, somewhat as a sailing ship "tacks."

And, as has been explained, the harder the wind blew the better the air
glider worked. In fact unless there was a strong gale it would not go
up.

"But it will be just what is needed out there in that part of Siberia,"
declared the exile, "for there the wind is never quiet. Often it blows
a regular hurricane."

"That's what we want!" cried Tom. He had made several models of the air
glider, changing them as he found out his errors, and at last he had
hit on the right shape and size.

Midway of the big glider, on which work was now well started, there was
to be an enclosed car for the carrying of passengers, their food and
supplies. Tom figured on