The Great Western Railway (GWR) GWR 5100 Class (known as the 3100 class between 1912 and 1927) was a class of 2-6-2T side tanksteam locomotives. It was the first of a series of broadly similar classes used principally for suburban passenger services.
^le Fleming, H.M. (February 1962). White, D.E. (ed.). The Locomotives of the Great Western Railway, part nine: Standard Two-Cylinder Classes. RCTS. p. J28-J38.