Puffing Billy
Puffing Billy is William Hedley's 1813 Wylam Colliery locomotive, the oldest surviving steam locomotive in the world. Built at Wylam Colliery's own workshops to a design by colliery viewer Hedley with engineman Jonathan Forster and blacksmith Timothy Hackworth (later famous in his own right as a locomotive engineer), Puffing Billy demonstrated for the first time that simple wheel-on-rail adhesion was sufficient for steam locomotion, a fundamental discovery that shaped all subsequent locomotive practice.
The Hedley team's key insight was that simple wheel-on-rail adhesion would be sufficient if the engine's weight was adequately distributed and the rails could support it. This contradicted the prevailing belief, exemplified by Blenkinsop's Salamanca of 1812, that rack-and-pinion drive was necessary. Hedley conducted experimental tests on a hand-cranked carriage to confirm that adhesion was sufficient for the loads expected.
The engine was completed at Wylam in 1813 or early 1814 with twin vertical cylinders driving the wheels through cross-beams in the so-called "grasshopper" arrangement. Construction of the engine was accompanied by the relaying of the Wylam Waggonway with cast-iron edge rails (rather than the previous wooden plate rails) to support the engine's weight. The name "Puffing Billy" reflects the distinctive exhaust sound of the steam discharging through the chimney.
Puffing Billy entered service at Wylam Colliery in 1814 and demonstrated for the first time that simple wheel-on-rail adhesion was sufficient for commercial steam locomotion. The engine's success was decisive: from 1814 onwards every successful British steam locomotive used adhesion drive. The engine worked at Wylam continuously from 1814 to 1862, nearly 50 years' service, an extraordinary working life. It was modified to 0-6-0 around 1815 (when the wooden waggonway proved inadequate even for the lightened weight), then back to 0-4-0 around 1830 after the line was relaid with stronger iron rails.
The engine was finally retired in 1862 and offered to the South Kensington Museum (now the Science Museum), where it has been on permanent display ever since. Puffing Billy is preserved largely as it was retired, an extraordinary survival of early-Victorian engineering. The sister engine Wylam Dilly (from Wylam Colliery, of similar design and approximately contemporary construction) is preserved at the National Museum of Scotland in Edinburgh. Together, Puffing Billy and Wylam Dilly are the two oldest surviving steam locomotives in the world.
Design and development
By 1812 the Wylam Colliery owners on Tyneside had been considering steam haulage for several years, the 1805 Trevithick engine had been intended for Wylam but never ran successfully. The colliery employed William Hedley as colliery viewer (the senior engineering manager). With engineman Jonathan Forster and blacksmith Timothy Hackworth (later famous in his own right as a locomotive engineer), Hedley designed a new locomotive specifically for Wylam conditions.
The Hedley team's key insight was that simple wheel-on-rail adhesion would be sufficient for steam locomotion if the engine's weight was adequately distributed and the rails could support it. This contradicted the prevailing belief, exemplified by Blenkinsop's Salamanca of 1812, that rack-and-pinion drive was necessary. Hedley conducted experimental tests on a hand-cranked carriage to confirm that adhesion was sufficient for the loads expected.
Construction of Puffing Billy began at Wylam Colliery's own workshops in 1813, with Hedley, Forster, and Hackworth as the principal builders. The engine was completed in 1813 or early 1814. The Wylam Waggonway was relaid with cast-iron edge rails (rather than the previous wooden plate rails) to support the engine's weight.
Service and withdrawals
Puffing Billy entered service at Wylam Colliery in 1814, successfully demonstrating for the first time that simple wheel-on-rail adhesion was sufficient for commercial steam locomotion. The engine's success was decisive: from 1814 onwards every successful British steam locomotive used adhesion drive. The rack-and-pinion approach of Salamanca continued in use at Middleton for another 20 years but was a dead-end technology after Puffing Billy.
The engine worked at Wylam continuously from 1814 to 1862, nearly 50 years' service, an extraordinary working life that took the engine from the Trevithick era through to the early-Victorian railway boom. It was modified to 0-6-0 around 1815 (when the wooden waggonway proved inadequate even for the lightened weight), then back to 0-4-0 around 1830 after the line was relaid with stronger iron rails. The engine's sister engine, "Wylam Dilly", also from Wylam Colliery and of similar design, gave parallel service.
Puffing Billy was finally retired from service in 1862, by which time it had been serving for nearly half a century alongside engines built fifty years more recently. The Wylam Colliery owners recognised the engine's historical significance and offered it to the South Kensington Museum (now the Science Museum). The engine has been on display at the Science Museum since 1862.
Identification features
The engine has a substantial cylindrical boiler with twin vertical cylinders mounted on either side of the boiler casing, driving the wheels through cross-beams (the so-called "grasshopper" arrangement) and gears. A tall vertical chimney rises from the boiler. The original 0-4-0 wheel arrangement was modified to 0-6-0 from approximately 1815 (for weight distribution on the wooden tramway) and back to 0-4-0 around 1830 (after iron rails were installed). The engine in its current preserved form is approximately 14 ft long. The name "Puffing Billy" reflects the distinctive exhaust sound of the steam discharging through the chimney.
Numbers and names
None (named locomotive)
Notable locomotives
- Puffing Billy (1813)
- Wylam Dilly (1813)
Allocations and regions
- Wylam Colliery Railway (Northumberland), 1813–1862