They were introduced in 1904 for work on small branch lines. The 4500 class was a later development with larger driving wheels. The 4400s were particularly used in hilly districts, notably the Princetown and Much Wenlock Branches.[1] All were withdrawn and scrapped between 1949 and 1955.[1]
The 4400, 4500 and 4575 classes, which all had 24 in (610 mm) stroke cylinders, the Standard 5 boiler and driving wheels under 5 ft (1.524 m), were collectively known as "Small Prairies", as opposed to the 5100, 3150, 5101, 6100, 3100 and 8100 classes, with 30 in (762 mm) stroke cylinders, Standard 2 or 4 boilers and driving wheels over 5 ft (1.5 m), known as "Large Prairies".
^ abcle Fleming, H.M. (February 1962). White, D.E. (ed.). The Locomotives of the Great Western Railway, part nine: Standard Two-Cylinder Classes. RCTS. p. J44-J46. {{cite book}}: Invalid |ref=harv (help)
Whitehurst, Brian (1973). Great Western Engines, Names, Numbers, Types and Classes (1940 to Preservation). Oxford, UK: Oxford Publishing Company. ISBN978-0-9028-8821-0. OCLC815661.
