In Tom Swift and His Giant Cannon, Tom has decided to invent a cannon that will make the longest shots on record in order to protect the Panama Canal when it is completed. He also has to invent the gunpowder that will propel the shell, neither of which is much of a challenge for this boy wonder. Of course, the time period in the book being around the time of WWI, it is only natural for a German spy to try to steal the plans for both the cannon and the powder. Tom, Ned and the giant Koku thwart the attempt. Along the way, Tom uses the cannon to relieve the pressure on a dam threatening to burst and engulf a nearby town. Tom fires a shell 31 miles, breaking the record. Simultaneously, the shot blows off the top of an island, exposing a huge opal mine the fortune hunter of the story, Alec Peterson, had been searching for. Everyone heads back to the U. S., satisfied with the inventions and richer in the process.
Victor Appleton was a pen name used by at least eight authors who wrote for Edward Stratemeyer. Of the 38 titles in the first Tom Swift series, Howard Garis (April 25, 1873 November 6, 1962) wrote the first thirty-five, while Harriet Stratemeyer Adams (December 12, 1892 March 27, 1982), daughter of Edward Stratemeyer, wrote the remaining three.