Editing Track gauge (section)

==="Standard" gauge appears===
[[File:Killingworth-locomotive.jpg|thumb|An early Stephenson locomotive]]Locomotives were being developed in the first decades of the 19th century; they took various forms, but [[George Stephenson]] developed a successful locomotive on the [[Killingworth Wagonway]], where he worked. His designs were successful, and when the [[Stockton and Darlington Railway]] was opened in 1825, it used his locomotives, with the same gauge as the [[Killingworth line]], {{Track gauge|4ft8in}}.<ref name = tomlinson>W W Tomlinson, ''The North Eastern Railway, its Rise and Development'', Andrew Reid & Co, Newcastle upon Tyne, 1915</ref><ref name = wood>Nicholas Wood, ''A Practical Treatise on Rail-Roads'', Longman, Orme, Brown, Green and Longmans, London, Third edition, 1838</ref>

The Stockton and Darlington line was very successful, and when the [[Liverpool and Manchester Railway]], the first intercity line, was opened in 1830, it used the same gauge. It too was very successful, and the gauge, widened to {{Track gauge|4ft8.5in|disp=or}}<ref name = tomlinson/> and named "[[standard gauge]]", was well on its way to becoming the established norm.