Léon Foucault Catholicism that he previously abandoned. Foucault died of what was probably a rapidly developing case of multiple sclerosis on 11 February 1868 in Paris and was buried in the Montmartre Cemetery. The asteroid 5668 Foucault was named for him. His is one of the 72 names inscribed on the Eiffel Tower. Collected Works: Léon Foucault Jean Bernard Léon Foucault (; 18 September 1819 – 11 February 1868) was a French physicist best known for his demonstration of the Foucault pendulum, a device demonstrating the effect of the Earth's rotation. He also made an early measurement of the speed of light,
Foucault pendulum vector diagrams of the pendulum swing the surface velocity vectors are angled upwards but on the opposite side the vectors are angled downwards. Since these vectors are all in the same plane as the pendulum swing there is no change of the surface in relationship to the plane of the pendulum swing. The surface velocity due to the Earth's rotation is a maximum at the Equator and is equal to the circumference (pi × the diameter of the Earth) per 24 hours (or 3.14159 × 12,756 ÷ 24 = 1670 km/h = 1 equatorial velocity unit, EVU). The time of an Earth's