Crampton

Thomas Crampton (a former GWR draughtsman under Gooch) patented in 1842 an arrangement that addressed the conflict between large driving wheels and a low boiler centre of gravity: by mounting the driving axle entirely behind the firebox, the boiler could sit low between the leading bogie and the driving wheel, and the driving wheel itself could be made very large (typically 7 ft, sometimes 8 ft).

Cramptons were built in modest numbers for British railways — including the LNWR, the South Eastern, and the GNR — but the layout was much more enthusiastically adopted in France and Germany, where it became the standard express type for the 1850s and into the 1860s. Over 300 Cramptons were built for Continental railways.

The British Cramptons were progressively withdrawn during the 1860s and 1870s as longer-wheelbase engines superseded them. On the Continent the type lasted longer; the last working Cramptons in Germany were withdrawn in the 1880s.

One Continental example, French Compagnie de l'Est No. 80 "Le Continent" (built 1852), is preserved at the Cité du Train in Mulhouse, France — the only surviving Crampton anywhere.

Very distinctive: a single pair of very large (7–8 ft) driving wheels mounted entirely behind the firebox, a long low boiler running over the leading carrying wheels, and outside cylinders mid-way along the boiler driving the single rear axle. The layout is unmistakable.

• Le Continent (1852, Cité du Train, Mulhouse)