A colour side elevation drawing of <a href="https://en.wikipedia.org/wiki/Robert_Stephenson" class="extiw" title="w:Robert Stephenson">Robert Stephenson</a>'s locomotive, <i>Rocket</i>, which won the 1829 "<a href="https://en.wikipedia.org/wiki/Rainhill_trials" class="extiw" title="w:Rainhill trials">Rainhill trials</a>" against four competitors on 10 return trips along 1.5 miles (2.4 km) of track, simulating the 30-mile (48 km) run between <a href="https://en.wikipedia.org/wiki/Liverpool_Lime_Street_railway_station" class="extiw" title="w:Liverpool Lime Street railway station">Liverpool</a> and <a href="https://en.wikipedia.org/wiki/Manchester_Liverpool_Road_railway_station" class="extiw" title="w:Manchester Liverpool Road railway station">Manchester</a>. <i>Rocket</i> was the only locomotive to complete the trials. The directors of the nearly completed <a href="https://en.wikipedia.org/wiki/Liverpool_and_Manchester_Railway" class="extiw" title="w:Liverpool and Manchester Railway">Liverpool and Manchester Railway</a> accepted that locomotives should operate services on their new line, and George and Robert Stephenson were given the contract to produce locomotives for the railway. The key conditions at the trials were strength, power and reliability, rather than speed alone. Efficiency was also important, as coal cost money, and having to frequently stop for water would negate any speed advantage over trains hauled by horses. 
(Text from the National Railway Museum UK. Image: SSPL 10301005.)
Unknown author<span style="display: none;">Unknown author</span>
CC BY 4.0
National Railway Museum, York -- <a rel="nofollow" class="external free" href="https://www.railwaymuseum.org.uk/objects-and-stories/stephensons-rocket-rainhill-and-rise-locomotive">https://www.railwaymuseum.org.uk/objects-and-stories/stephensons-rocket-rainhill-and-rise-locomotive</a>