Abraham Lincoln was the only United States President to hold a patent.
As a young man, Abraham Lincoln took a boatload of merchandise down the Mississippi River from New Salem to New Orleans. At one point the boat slid onto a dam and was set free only after heroic efforts. In later years, while traveling on the Great Lakes, Lincoln’s ship ran a foul of a sandbar. These two similar experiences led him to conceive his invention. Abraham Lincoln received Patent #6,469 for “A Device for Buoying Vessels Over Shoals” on May 22, 1849. 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.
In 1858, Abraham Lincoln called the introduction of patent laws one of the three most important developments “in the world’s history,” along with the discovery of America and the perfection of printing.
During the Civil War, Lincoln took a personal interest in new weapons, advocating the use of ironclad ships, observation balloons, breech-loading rifles, and machine guns.. Lincoln declared that “the patent system added the fuel of interest to the fire of genius.”