Bowen-Cooke's predecessor
George Whale had built 50 related
Precursor Tank Class 4-4-2 engines. In terms of familial relationships, Prince of Wales Tank was both a superheated and extended version of the Precursor Tank, and a version of the
Prince of Wales Class 4-6-0 steam locomotive with side tanks and a bunker which necessitated an extension to the frames and trailing
pony truck. They were used on suburban services out of
Euston station and from an early date also used on passenger services between Shrewsbury and Swansea (Victoria) over the steeply-graded Central Wales line, a journey of some . The LNWR built 47 of the
superheated tanks between 1910 and 1916 under Charles Bowen-Cooke. ==LMS service==