A Float of Gold is an adventure novel about two boys who are on board a school ship, but who are cast overboard during a storm. They drift ashore on a Pacific island, and get tangled up in an adventure where they first have to escape murderous smugglers, with Native Americans coming to their aid.
The Native Americans are the descendants of the Incas, and they believe the boys to be the sons of heaven. The boys then embark on a treacherous trek through the jungle, and it soon becomes clear that they are being pursued by other treasure hunters. Everything comes to a head, Indiana Jones-style.