Inventor: Abraham Lincoln
Abraham Lincoln had a strong interest in new technology and is the only U.S. President to hold a patent. Lincoln received Patent # 6,469 for "A Device for Buoying Vessels Over Shoals" on May 22, 1849. The invention consists of a set of bellows attached to the hull of a ship just below the water line. On reaching a shallow place, the bellows are filled with air and the vessel, thus buoyed, is expected to float clear.