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
In Which We Serve Association Award for Best Foreign Film in 1943. A Region 2 DVD with a running time of 96 minutes was released by Carlton on 11 October 1999. A Region 1 DVD was released as part of the David Lean Collection by MGM on 7 September 2004. It features subtitles in English, Spanish and French and an English audio track in Dolby Digital 1.0. In March 2012, The Criterion Collection released "In Which We Serve" on Blu-ray and DVD as part of the "David Lean Directs Noel Coward" Box Set, which includes a short documentary on the making of "In Which