Monowheels

A monowheel (or motorwheel) is one big wheel with rider and engine (if any) inside its circumference. It is not to be confused with a unicycle, which has the rider above the wheel. Check out an amazing gallery of monowheels from as far back as 1869 at http://www.dself.dsl.pipex.com/MUSEUM/TRANSPORT/motorwhl/motorwhl.htm

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