the railway, it was designed to show how the 2-2-2 express engines could be improved; its driving wheels were larger than those of the successful Fire Fly class. It broke its leading axle after a short while in service and was subsequently rebuilt as a 4-2-2, becoming part of the Iron Duke class. Iron Duke class Rover class Replica A working replica of Iron Duke was constructed in 1985 using parts from two Hunslet Austerity tanks for the 'Great Western 150' celebrations. It is part of the National Railway Collection but is currently on long-term loan to the Didcot Railway Centre, which has a section of working broad gauge track. The boiler certificate has expired so it cannot currently be steamed. The replica appeared in The Railway Series book Thomas and the Great Railway Show, in which it was portrayed with whiskery eyebrows and a walrus moustache. References External links Iron Duke 4-2-2 locomotives Broad gauge (7 feet) railway locomotives Railway locomotives introduced in 1846 Railway locomotives introduced in 1871