Tom Swift and His Submarine Boat

Tom Swift's father has been working diligently on a secret project, which he reveals at the beginning of the book as a submarine. With the submarine, named the Advance, he plans to enter a contest for a government prize of $50,000. While in New Jersey to launch the submarine, Tom reads in a newspaper that a ship named the Boldero sank off the coast of Uruguay during a storm, taking down with it the sum of $300,000 in gold bullion.