Foucault pendulum with a 67-m-long wire from the dome of the Panthéon, Paris. The plane of the pendulum's swing rotated clockwise approximately 11.3° per hour, making a full circle in approximately 31.8 hours. The original bob used in 1851 at the Panthéon was moved in 1855 to the Conservatoire des Arts et Métiers in Paris. A second temporary installation was made for the 50th anniversary in 1902. During museum reconstruction in the 1990s, the original pendulum was temporarily displayed at the Panthéon (1995), but was later returned to the Musée des Arts et Métiers before it reopened in 2000. On April 6,
In Which We Serve leads to a flashback in which Blake remembers how he met his wife-to-be, Freda, on a train while on leave. It is also revealed that she is related to the "Torrin"'s affable Chief Petty Officer Hardy (Miles). When both men return to sea, Freda moves in with CPO Hardy's wife and mother-in-law. The "Torrin" participates in the Dunkirk evacuation of the British Expeditionary Force, (portrayed in the film by the 5th Battalion of the Coldstream Guards). Meanwhile, the nightly Blitz takes its toll on British towns. Blake soon gets a letter from home to say that Freda has given birth