This bizarre vehicle was based on a design by Leonardo da Vinci! The concept for this wheel, popularly known as a monowheel, was patented in 1930 by a British inventor called Dr. J. A. Purves, who based his design on Da Vinci’s drawing. Purves was so sure that his monowheel would be the next great thing in the automobile world that he even wrote an article about it in the journal “Popular Mechanics.”
The monowheel ran well, but it had a major weakness when it came to braking and accelerating. The force would cause the driver’s carriage to spin around the wheel, similar to when a hamster stops abruptly when running on a wheel. Not pleasant!