LSWR A12

The LSWR A12 Class, nicknamed the Jubilees, was a series of 90 inside-cylinder 0-4-2 passenger tender locomotives designed by William Adams and built at Nine Elms Works and by outside contractors between 1887 and 1895, named the Jubilee Class to mark Queen Victoria's Golden Jubilee of 1887 and intended for the medium-weight secondary passenger and semi-fast working on the LSWR's extensive routes across southern England. With 90 examples built over eight years, the A12 Class was one of Adams's most numerous locomotive types and formed the backbone of the LSWR's secondary passenger operation through the 1890s and into the Edwardian era.

Adams designed the A12 as a passenger tender engine of modest but adequate power for the semi-fast and secondary passenger services across the LSWR's varied territory: the stopping trains to Southampton, Portsmouth, Bournemouth, and Exeter from Waterloo; the rural services through the Hampshire and Dorset countryside; and the cross-country workings that connected the scattered towns of the LSWR's network. The 0-4-2 wheel arrangement — four coupled driving wheels and a trailing axle — gave adequate adhesion for the passenger loads involved while the trailing axle supported the firebox weight and allowed a slightly wider grate than a pure 0-4-0 would have permitted.

The Jubilee Class worked LSWR secondary passenger duties reliably through the 1890s and into the Southern Railway era. Under Drummond's superintendency from 1895 the class was supplemented by his own more powerful types on the most important services, but the A12s continued on secondary and rural duties for many years. The SR inherited all survivors in 1923 and used them on former-LSWR secondary routes until withdrawal in the 1930s. None was preserved, which represents a gap in the collection of Adams LSWR passenger types — though his radial tank (30583) and the Beattie well tanks give some representation to the pre-Drummond LSWR era.