Sans Pareil
Sans Pareil was Timothy Hackworth's 1829 locomotive, the most powerful engine to compete in the Rainhill Trials of October 1829, but defeated by Robert Stephenson's Rocket through inferior steaming and high coal consumption.
The design followed Hackworth's successful Royal George approach: twin inverted vertical cylinders mounted on top of the boiler, a return-flue cylindrical boiler at approximately 50 psi, and a 0-4-0 wheel arrangement. Hackworth aimed to win Rainhill by raw power, the engine was designed to haul the heaviest load and demonstrate sustained running, on the assumption that this was what the Liverpool & Manchester Railway most valued.
Sans Pareil entered the Rainhill Trials alongside Rocket, Novelty, Cycloped, and Perseverance. The engine completed parts of the trials successfully but encountered repeated mechanical problems including a cracked cylinder, and its return-flue boiler was inferior to Rocket's multi-tube design, Sans Pareil consumed substantially more coke per mile than Rocket and had a lower maximum speed. The judges awarded the prize to Rocket on 14 October 1829.
Sans Pareil did not win but had performed creditably enough that the L&MR purchased the engine for use during the line's construction. After the L&MR opened in September 1830, the engine was sold to the Bolton & Leigh Railway in 1832, where it worked until approximately 1844.
Sans Pareil survives, currently on display at Locomotion: The National Railway Museum at Shildon, having been transferred from the Science Museum in 2017. The engine is preserved largely in its later working form. A working full-size replica was built in 1979 by the National Railway Museum and has been periodically operated for special demonstrations.
Design and development
By 1829 Timothy Hackworth's reputation as a locomotive engineer had been established by Royal George of 1827. When the Liverpool & Manchester Railway announced the Rainhill Trials of October 1829, the motive-power competition with a £500 prize, Hackworth resolved to enter despite the substantial financial risk involved.
Sans Pareil was Hackworth's response. The design followed his successful Royal George approach: twin inverted vertical cylinders, return-flue boiler, 0-4-0 wheel arrangement. Hackworth aimed to win Rainhill by raw power, the engine was designed to haul the heaviest load and demonstrate sustained running, on the assumption that this was what the L&MR most valued. The engine was built largely at Hackworth's Shildon works with significant subcontracted parts.
Service and withdrawals
Sans Pareil entered the Rainhill Trials in October 1829 alongside Rocket, Novelty, Cycloped, and Perseverance. The engine completed parts of the trials successfully but encountered repeated mechanical problems including a cracked cylinder. Sans Pareil consumed substantially more coke per mile than Rocket, its return-flue boiler was inferior to Rocket's multi-tube design, and its lower maximum speed put it at a disadvantage.
The judges awarded the prize to Rocket on 14 October 1829. Sans Pareil did not win but had performed creditably enough that the L&MR purchased the engine for use during the line's construction.
After the L&MR opened in September 1830, the engine was no longer needed there and was sold to the Bolton & Leigh Railway in 1832. Sans Pareil worked the Bolton & Leigh until approximately 1844, when it was withdrawn from service. The engine was preserved and presented to the Patent Office Museum (now the Science Museum), where it has been on display since the 1860s.
Identification features
A distinctive Hackworth outline, twin inverted vertical cylinders mounted on top of the boiler at the rear, with the connecting rods coming down to drive the rear coupled axle through cross-beams. The return-flue boiler arrangement means the firebox and chimney are both at the same end of the boiler, visually unusual for the period and easily distinguished from the Stephenson Rocket-style engines.