Sanspareil II
Design and development
After the original Sanspareil failed at the Rainhill Trials in 1829, Hackworth continued in his role as locomotive superintendent of the Stockton & Darlington Railway, building a series of heavy 0-6-0 coal engines that retained the vertical-cylinder, return-flue boiler layout he had championed at Rainhill. Sanspareil II, completed in 1837 at Hackworth's Soho Works in Shildon, was an enlargement of these earlier engines: a 0-6-0 with twin vertical cylinders mounted at the rear of the boiler, driving through long connecting rods to the rear axle, with side rods coupling all six wheels.
Hackworth's adherence to this layout, despite its declining popularity, reflected his belief that the return-flue boiler delivered better steam-raising for heavy slow-speed work — and the Sanspareil II proved highly capable on the Stockton & Darlington's coal trains.
Service and withdrawals
Sanspareil II worked the Stockton & Darlington's coal traffic from 1837 and remained in service for many years, eventually being withdrawn in the 1860s. Not preserved.
Identification features
0-6-0 with vertical cylinders mounted at the rear of the boiler, driving the rear axle through long connecting rods, with side-rod coupling to the front and middle axles. Distinct return-flue boiler with chimney at the same end as the cylinders. Visually quite unlike contemporary Stephenson practice.
Notable locomotives
- Sanspareil II (1837, not preserved)