me! That is surprising! Yes--yes! Of course if it's
true it means a big thing, I can understand that. What's that? No, I
couldn't make a promise like that. I'm sorry, but----"

Then the person at the other end of the wire must have plunged into
something very interesting and absorbing, for Tom did not again
interrupt by interjected remarks.

Tom Swift, as has been said, was an inventor, as was his father. Mr.
Swift was now rather old and feeble, taking only a nominal part in the
activities of the firm made up of himself and his son. But his
inventions were still used, many of them being vital to the business
and trade of this country.

Tom and his father lived in the village of Shopton, New York, and their
factories covered many acres of ground. Those who wish to read of the
earliest activities of Tom in the inventive line are referred to the
initial volume, "Tom Swift and His Motor Cycle." From then on he and
his father had many and exciting adventures. In a motor boat, an
airship, and a submarine respectively the young inventor had gone
through many perils. On some of the trips his chum, Ned Newton,
accompanied him, and very often in the party was a Mr. Wakefield Damon,
who had a curious habit of "blessing" everything that happened to
strike his fancy.

Besides Tom and his father, the Swift household was made up of
Eradicate Sampson, a colored man-of-all-work, who, with his mule
Boomerang, did what he could to keep the grounds around the house in
order. There was also Mrs. Baggert, the housekeeper, Tom's mother
being dead. Mr. Damon, living in a neighboring town, was a frequent
visitor in the Swift home.

Mary Nestor, a girl of Shopton, might also be mentioned. She and Tom
were more than just good friends. Tom had an idea that some day----.
But there, I promised not to tell that part, at least until the young
people themselves were ready to have a certain fact announced.

From one activity to another had Tom Swift gone, now constructing some
important invention for himself, as among others, when he made the
photo-telephone, or developed a great searchlight which he presented to
the Government for use in detecting smugglers on the border.

The book immediately preceding this is called "Tom Swift and His Big,
Tunnel," and deals with the efforts of the young inventor to help a
firm of contractors penetrate a mountain in Peru. How this was done
and how, incidentally, the lost city of Pelone was di