A Broad Gauge Prodigy — James Pearsall's 9-foot 4-2-4 tank engine, 1853: Bristol and Exter Railway.
Although the broad gauge main line south-westwards from Bristol had been strongly sponsored by the Great Western, it was at first an independent company, and its management enjoyed displaying its independence on many occasions — sometimes to tlie considerable embarrassment of the Great Western. James Pearson was locomotive superintendent, and he designed the extraordinary 4-2-4 tank engines, with a single pair of driving wheels 9 ft. in diameter. Eight of them were originally built, and they handled the express traffic between Bristol and Exeter for several years. Our picture shows their peculiar appearance from the rear end, but they were no less extraordinary at the front. The cylinders were partly enclosed in the base of the D-shaped smokebox, but the latter was so short from front to back that part of the cylinders protruded at the front. They had also a most unusual form of suspension of the main driving axles. The housing for the outer helical spring can be seen hanging down outside the driving wheel. The original engines were scrapped after a life of about 16 years, and four new engines with 8 ft. 10 in. driving wheels were built in their place. After the Bristol and Exeter Railway was absorbed by the Great Western they were converted into 4-2-2 tender engines. [Nock, p. 120]
Bibliography
Nock, O. S. The Pocket Encylopaedia of British Steam Locomotives. Illustrations by Clifford and Wendy Meadway. Poole: Blandford Press, 1964.
Last modified 11 September 2004