. ▁The ▁new ▁ 2 - 4 - 2 T s ▁had ▁ ▁couple d ▁whe els ▁and ▁ ▁cyl ind ers . ▁The ▁second ▁batch ▁were ▁slightly ▁longer ▁than ▁the ▁prototype , ▁resulting ▁in ▁greater ▁tank ▁capacity , ▁and ▁the ▁third ▁lot , ▁delivered ▁under ▁Church ward , ▁were ▁slightly ▁larger ▁again , ▁and ▁had ▁t aper ▁bo ilers . ▁The ▁class ▁gained ▁the ▁nick name ▁" B ird c age " ▁due ▁to ▁their ▁( for ▁the ▁G WR ) ▁unus ually ▁sp a cious ▁c abs . ▁ ▁Use ▁The ▁ 3 6 0 0 ▁class ▁were ▁fitted ▁with ▁steam ▁revers ing ▁g ear , ▁steam ▁bra kes , ▁and ▁two ▁steam - oper ated ▁water ▁pick - ups ▁for ▁forward ▁and ▁reverse ▁working . ▁This ▁reflect s ▁their ▁intended ▁work ▁as ▁fast ▁sub urban ▁engines . ▁About ▁half ▁were ▁employed ▁on ▁such ▁duties ▁in ▁the ▁B irmingham ▁area . ▁The ▁rest ▁worked ▁in ▁the ▁London ▁area , ▁though ▁later ▁a ▁few ▁worked ▁Ch ester - B ir ken head ▁trains , ▁and ▁some ▁were ▁allocated ▁to ▁South ▁Wales ▁sh eds . ▁They ▁were ▁essentially ▁passenger ▁train ▁locomot ives , ▁and ▁were ▁eventually ▁su pers eded ▁by ▁Col lett ' s ▁ 2 - 6 - 2 T s . ▁All ▁were ▁with dra wn ▁and ▁scra pped ▁between ▁ 1 9 3 0 ▁and ▁ 1 9 3 4 . ▁ ▁References ▁ ▁S ources ▁ ▁External ▁links ▁▁▁ 3 6 0 0 ▁' B ird c age '