The change in direction of the swinging brass ball hanging from a steel cable is almost indiscernible. Called a Foucault (pronounced “foo-KOH”) pendulum after its designer, French physicist Léon Foucault, the device was conceived in 1851 to demonstrate the rotation of the Earth. This pendulum, about the size of a child’s balloon, hanging in the center of a circular staircase in a University of Texas office building since 1983, is the first Foucault pendulum successfully installed in Texas. The swinging ball progresses clockwise 180 degrees every 24 hours. As the pendulum moves back and forth, it actually swings on the same plane while the Earth rotates underneath it.
Information is power. Support the free press, so we can support Austin. Support the Chronicle