GWR 47XX 2-8-0 No 4700 after being fitted with the larger, standard boiler for the class in 1921. Note the snifting valves on its cylinders.

Peter Kerslake says "The standard G.W.R. number one boiler as fitted to ths engine, the first of her class of nine, and built at Swindon in 1919, soon proved indequate for such a large engine and 4700 received the larger number seven boiler shown here in May of 1921 together with the outside main steam pipes now in position, the remainder of the class being so equipped from being built during 1922/ 23.
4700 spent most of her working life at either Old Oak Common or Southall with a spell at Bristol St. Philip's Marsh and was condemned in October of 1962 and sold to Kings of Norwich for disposal there.
The "4700's" handsome lines were further enhanced in their late years when the former unlined black livery gave way to a fully lined green, reflecting their fine performances put in whilst rostered upon heavy passenger duties between Paddington and Newton Abbot and Plymouth, especially on Saturdays during the Summer Services in the late 'fifties and early 'sixties. "

Photo: W.J. Reynolds/Rail Archive Stephenson