Pendulum plane of oscillation of a pendulum, like a gyroscope, tends to stay constant regardless of the motion of the pivot, and that this could be used to demonstrate the rotation of the Earth. He suspended a pendulum free to swing in two dimensions (later named the Foucault pendulum) from the dome of the Panthéon in Paris. The length of the cord was . Once the pendulum was set in motion, the plane of swing was observed to precess or rotate 360° clockwise in about 32 hours. This was the first demonstration of the Earth's rotation that didn't depend on celestial
Foucault's Pendulum Foucault's Pendulum Foucault's Pendulum (original title: "Il pendolo di Foucault" ) is a novel by Italian writer and philosopher Umberto Eco. It was first published in 1988, and an English translation by William Weaver appeared a year later. "Foucault's Pendulum" is divided into ten segments represented by the ten Sefiroth. The satirical novel is full of esoteric references to Kabbalah, alchemy, and conspiracy theory—so many that critic and novelist Anthony Burgess suggested that it needed an index. The pendulum of the title refers to an actual pendulum designed by French physicist Léon Foucault to demonstrate Earth's rotation, which has symbolic