Kater's pendulum minutes per day slower than at Paris, or equivalently the length of a pendulum with a swing of one second there was 1¼ Paris "lines", or 2.6 mm, shorter than at Paris. It was realized by the scientists of the day, and proven by Isaac Newton in 1687, that this was due to the fact that the Earth was not a perfect sphere but slightly oblate; it was thicker at the equator because of the Earth's rotation. Since the surface was farther from the Earth's center at Cayenne than at Paris, gravity was weaker there. Since that time pendulums began
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