“Well, I might as well wait until he is through,” mused Ned, as he started to leave the room.  Then as Tom motioned to him to remain, he murmured:  “He may have something to say to me later.  But I wonder who is talking to him.”

There was no way of finding out, however, until Tom had a chance to talk to Ned, and at present the young scientist was eagerly listening to what came over the wire.  Occasionally Ned could hear him say: 

“You don’t tell 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 Bit, 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, incidental-ly, the lost city of Pelone was discovered, bringing joy to the heart of Professor Swyington Bumper, will be found fully set forth in the book.