The invention consisted of a set of bellows attached to the hull of a ship just below the water line. After reaching a shallow place, the bellows were filled with air that buoyed the vessel higher, making it float higher. The invention was never marketed, it was discovered that the extra weight the device added increased the probability of running onto sandbars, defeating the purpose of the invention.
Abraham Lincoln whittled the model for his patent application with his own hands out of wood. It is on display at the Smithsonian Institution National Museum of American History.