The Sunken Isthmus; Or, Frank Reade, Jr., in the Yucatan Channel.

At the turn of the century, when the world still pulsed with faith in invention and the unknown shimmered just beyond the horizon, Luis Senarens crafted a boy's-own adventure that pulses with pure, undiluted wonder. The story opens on Mr. Wilbur Address, standing before the World's Geographical Society with a theory so audacious it borders on heresy: a sunken isthmus once bridged Cuba and the Yucatan, a lost land swallowed by the sea. The academics scoff until the name Frank Reade, Jr. enters the room the brilliant young inventor who has just completed the Sea Diver, a submarine engineerd to plumb depths no human eye has ever witnessed. What follows is a race against a villainous rival, Hardy Poole, a treasure hunter whose motives are as murky as the Yucatan depths themselves. Senarens writes with the breathless momentum of a man who knows exactly what his young readers crave: machines that think, oceans that hide secrets, and a hero whose genius is matched only by his courage. This is science fiction before it became science fiction, when the future was still a frontier and invention was the purest form of heroism.