0-4-2 Steam Locomotives in Great Britain

Class Dock tank (Locobase 2184)

Data from [] (9 May 2003 -- the website of the London & North Western Railway Society's Goods Locomotives "exhibit" and from "Four-Coupled Shunting Engine, L & NW Ry," The Locomotive Magazine, Vol V (February 1900), p.24 and W A Tuplin, The Steam Locomotive: Its Form and Function (New York: Charles Scribner's Sons, 1974),

Francis W Webb wanted a yard engine that could negotiate quite tight curves without derailing, so he placed a trailing axle in a "carriage"(known to most as a Bissell truck) at the end of an arm that pivoted on a point just behind the rear driving set. "[I]t will readily be seen," said the grammatically precise LM author," that with this pivot as a center the carriage is free to move laterally and accommodate itself to the road." Indeed, a conical roller and two inclined planes under the carriage meant that the axle also was self-centering. This trailing-truck design earned the class the nickname "Bissell tanks".

Locobase wants to describe the tank as a "pannier tank", but realizes that the square cross-section of the tank does in fact lie on the boiler (rather than flanking it). The whole locomotive looks as if it had been carved out of a block of wood. The class suited its requirement quite well and some operated until 1967.