https://www.scientificamerican.com/article/parlor-trick-keeps-monorails-on-track/

“The wrestling gyroscope has been a popular feature of the Young Men’s Christian Association gyroscope lectures in China. It consists of a strong bicycle wheel with the rim loaded with lead pipe. When spun up to high speed and set upon its edge, it will stand up with a light list to one side, and will precess slowly around on a nearly vertical axis. A member of the audience is invited to use a strong staff padded at one end with a solid rubber ball and make the wheel lie down on its side. Unbelievable as it may seem, the strongest man is unable to push it over. This experiment delights the audience. The audience then also readily comprehends how it may be possible for a wheel weighing tons and running thousands of revolutions per minute to stabilize a monorail car.”

—Scientific American, January 1914