The Foucault Pendulum is named for the French physicist Jean Foucault (pronounced "Foo-koh), who first used it in 1851 to demonstrate the rotation of the earth. It was the first satisfactory ...

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 ...