Speed recorder from the 'The Mallard' 4-6-2 steam locomotive no 4468, 1938.
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The Flaman speed recorder is shown contained in a sealed bras casing. The A4 Pacific clas 'The Mallard' was designed by Sir Nigel Gresley (1876-1941), the chief engineer of the London & North Eastern Railway (LNER). On Sunday 3 July 1938, the 4-6-2 locomotive reached a speed of 126 mph (203 kph) on a straight stretch of track between Grantham and Peterborough, achieving a new world speed record for steam locomotives which remains unbroken to this day.