burying it out of sight forever under thousands of tons of the frozen bergs.
After a desperate journey Tom and his friends reached civilization, with a large supply of gold. Tom regretted very much the destruction of the airship, but he at once set to work on another—a monoplane this time, instead of a combined aeroplane and dirigible balloon. This new craft he called the Humming Bird and it was a "sky racer" of terrific speed. In it, as we have said, Tom brought a specialist to operate on his father, when, because of a broken railroad bridge, the physician could not otherwise have gotten to Shopton. He and Tom traveled through the air at the rate of over one hundred miles an hour. Later, Tom took part in a big race for a ten-thousand-dollar prize, and won, defeating Andy Foger, and a number of well-known "bird-men" who used biplanes and monoplanes of a more or less familiar type.
The government became interested in Tom's craft, the Humming Bird, and, as told in the ninth book of this series, "Tom Swift and His Sky Racer," they secured some rights in the invention.
And now Tom, who had done nothing for several months following the great race—that is,
