The coal was hot. The crew were ready. On July 3rd, 1938, the 4468 Mallard, an A4-class steam locomotive, was performing an alleged brake test for its London and North Eastern Railway (LNER) owners.

Seventy-five years ago a world record was achieved by a steam engine called Mallard. Its design inspired by Bugatti motor cars, the A4 Pacific class locomotive thundered along the east coast ...