Demonstrates the rotation of the earth. The pendulum always goes back and forth to the same spot, but the earth rotates underneath the pendulum, so the pendulum floats over progressively different numbers.

"The 240-pound brass ball, suspended by a cable 40 feet long, swings in a constant direction while the Earth turns beneath it. The pendulum is mounted to a bearing in the rotunda ceiling that does not turn with the building as it rotates with the Earth. A ring magnet at the bearing gives a little tug on each swing of the pendulum to keep the pendulum in motion. As the day passes, the pendulum knocks over pegs set up in the pendulum pit and indicates the progress of rotation."

- from griffithobs.org

They used to have pegs set up, but not any more after the renovation.

Drawings about science and inventions from young and old.

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This is a giant Tesla coil inside a Farady Cage. They set it off every 15 minutes and it truly is cool. This is not a very good picture.

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