Nigel Gresley
Sir Herbert Nigel Gresley (19 June 1876 – 5 April 1941) was an English railway engineer. He was one of Britain's most famous steam locomotive engineers, who rose to become Chief Mechanical Engineer (CME) of the London and North Eastern Railway (LNER). He was the designer of some of the most famous steam locomotives in Britain, including the LNER Class A1 and LNER Class A4 4-6-2 Pacific engines. An A1 Pacific, "Flying Scotsman", was the first steam locomotive officially recorded over 100 mph in passenger service, and an A4, number 4468 "Mallard", still holds the record for being the fastest steam locomotive in the world (126 mph).
History of rail transport in Great Britain to 1830
Trevithick built a third locomotive in 1808, "Catch Me Who Can", which ran on a temporary demonstration railway in Bloomsbury, London. Members of the public were able to ride behind at speeds up to . However, it again broke the rails and Trevithick was forced to abandon the demonstration after just two months.
The first commercially successful steam locomotive was the twin cylinder "Salamanca", built in 1812 by John Blenkinsop and Matthew Murray for the gauge Middleton Railway. Blenkinsop believed that a locomotive light enough to move under its own power would be too light to generate sufficient adhesion, so he designed a rack and pinion system for the line. This was despite the fact that Trevithick had demonstrated successful adhesion locomotives a decade before. The single rack ran outside the narrow gauge edge-rail tracks and was engaged by a cog-wheel on the left side of the locomotive. The cog-wheel was driven by two cylinders embedded into the top of the center-flue boiler. Four such locomotives were built for the railway, and they worked until the early 1830s.