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Stephenson's Rocket
From: Science Museum
| By:
Dieter W Hopkin |
EDITOR'S INTRODUCTION |
In 1829 the English engineers George and Robert Stephenson created Rocket, one of the world's first successful steam locomotives. Rocket's ground-breaking design and technical success meant that steam locomotive-hauled railways became a firm driving force in the Industrial Revolution. Dieter Hopkin of the Science Museum tracks its development--from conception and design through to its early redundancy--and shows how a pioneering design can be transformed from an idea for a specific competition to one with wide-reaching, major commercial value. |
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| Robert Stephenson, 1803-1859. | |
 n the history of the early development of the steam-railway locomotive there is no more significant machine than Rocket. Its design and construction produced a momentous leap forward in locomotive and railway practice as it embodied the fundamental principles which were followed through the 150-year history of the reciprocating steam locomotive. It clearly demonstrated the superiority of moving locomotive engines and rope-haulage systems for railway transport. Yet Rocket was an experimental machine at the forefront of a rapidly developing technology. As a result it was soon modified and rendered obsolete in little over a decade. |
The first steam locomotives were built for hauling heavy loads rather than for speed. They offered little advantage over stationary engines and rope haulage. The directors of the Liverpool and Manchester Railway (L&MR) required a faster and better form of motive power for their intercity railway. They offered a premium of £500 for a 'Locomotive Engine which shall be a decided improvement on those now in use'. Competing engines were to be tested on a length of the new railway at Rainhill, east of Liverpool. |
Rocket was built at the Robert Stephenson and Company locomotive works in Newscastle-upon-Tyne to compete for the premium at the Rainhill Trials of October 1829. It was the eighteenth steam locomotive built by the company which combined the experience of George Stephenson (1781-1848) and his son Robert (1803-59). It was Robert who undertook the construction of this innovative machine: a lightweight locomotive with a single pair of driving wheels, built for speed. |
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| Rocket in its modified and partially reconstructed form, as exhibited at the Science Museum, London. | |
In the trials, Rocket was in competition with four other machines and emerged the clear winner. The locomotive's success was largely due to the incorporation of a number of important design features. The multi-tube fire tube boiler had been suggested to the Stephensons by Henry Booth and was greatly superior to the more unusual single or twin flue boiler barrel. Twenty-five three-inch-diameter tubes in the boiler increased the heating surface and, as a result, the amount of steam the boiler could produce. This was further assisted by use of a water jacket around the firebox. Steam from the cylinders was exhausted through a blast-pipe up the chimney which gave induced draught in the firebox and made the fire burn more fiercely. Rocket was also built with steeply angled cylinders which drove directly to a single pair of driving wheels with crank pins at right-angles; a more effective system than the vertical cylinders of earlier engines. The multi-tube boiler, blast-pipe exhaust and the two-cylinder simple drive mechanism are the three fundamentals of steam locomotive design which were first combined in Rocket. |
 Although built expressly to compete for the first prize and not for everyday traffic work, Rocket so impressed the directors of the L&MR that they purchased it for use on the line and ordered four similar locomotives from Robert Stephenson and Company. Rocket assisted with works trains during construction and on 15 September 1830 took part in the opening ceremonies during which it was involved in an accident in which William Huskisson, then MP for Liverpool, was killed. This was the first recorded passenger fatality on a railway. |
Within 18 months of its construction Rocket had been significantly rebuilt. The cylinders were swapped around and lowered from thirty eight to eight degrees from the horizontal to improve the riding of the locomotive, and the splayed-out chimney base was replaced by a more practical drum-shaped smokebox. Other changes included the addition of a buffer beam and a reduction in the chimney size. |
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| Detail of Rocket's driving wheel and nameplate. | |
By the mid-1830s 'Rocket-type' locomotives and their successors had displaced the prototype on the L&MR. Rocket was sold in 1836 to Messrs Thompson of Kirkhouse near Carlisle. It had a three-year working life on the Brampton Colliery Railway in Cumberland but by about 1840 it was considered too lightweight and worn out to work coal trains and was laid aside. |
A proposal to show the locomotive at the Great Exhibition of 1851 in London came to nothing, and the derelict locomotive was presented by Messrs Thompson to the Patent Office Museum in 1862. For public display Stephenson and Company undertook some restoration work on Rocket. This included the addition of parts incompatible with the rebuilt condition of the locomotive. Some of these have since been removed. What remains are mainly those parts believed to date from 1829-36, as surveyed in detail at the National Railway Museum in 1999, and represent the bare bones of the locomotive in its rebuilt form. |
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