Fizeau–Foucault apparatus unit. At the time, Foucault was working at the Paris Observatory under Urbain le Verrier. It was le Verrier's belief, based on extensive celestial mechanics calculations, that the consensus value for the speed of light was perhaps 4% too high. Technical limitations prevented Foucault from separating mirrors R and M by more than about 20 meters. Despite this limited path length, Foucault was able to measure the displacement of the slit image (less than 1 mm) with considerable accuracy. In addition, unlike the case with Fizeau's experiment (which required gauging the rotation rate of an adjustable-speed toothed wheel), he could
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