The Foucault pendulum at Griffith Observatory in Los Angeles, USA

© GIPhotoStock/Science Photo Library

The Foucault pendulum at Griffith Observatory in Los Angeles, USA

French physicist Léon Foucault first demonstrated his pendulum experiment in 1851 in Paris. Since then, it’s become a mainstay of science centres and museums around the world. His simple, elegant device – little more than a weight on a wire, with suspending hardware that allows the pendulum to swing in any direction – is considered the first to prove the rotation of the Earth on its axis. This Foucault pendulum swings in the halls of Griffith Observatory in Los Angeles, California.