With his electric rifle he did some wonderful shooting, and in
the "City of Gold" made some strange discoveries, part of the
fortune he secured enabling him to build his sky racer. It was in
a land of giants that Tom was made captive, but he succeeded in
escaping, and brought two giants, of whom Koku was one, away
with him.

Following this achievement Tom invented a wizard camera and a
great searchlight, which, with his giant cannon, was purchased by
the United States Government. Work on his photo-telephone and his
aerial warship, the problem of digging a big tunnel, and then
traveling to the land of wonders, kept Tom Swift very busy, and
he had just completed a wonderful piece of work when the present
story opens.

This last achievement was the perfecting of a machine to aid in
the great World War and you will find the details set down in the
volume which immediately precedes this. "Tom Swift and His War
Tank," it is called, and in that is related how he not only
invented a marvelous machine, but succeeded in keeping its secret
from the plotters who tried to take it from him. In this Tom was
helped by the inspiration of Mary Nestor, whom he hoped some day
to marry, and by Ned Newton, a chum, who, though no inventor
himself, could admire one.

Ned and Tom had been chums a long while, but Ned inclined more
to financial and office matters than to machinery. At times he
had managed affairs for Tom, and helped him finance projects. Ned
was now an important bank official, and since the United States
had entered the war had had charge of some Red Cross work, as