Caledonian 0-8-0 Locomotives in Great_Britain

Class 492 / 4F (Locobase 10446)

Data from "Eight-Coupled Mineral Tank, Caledonian Ry," The Locomotive Magazine, Vol X (12 March 1904), p. 47.

Class 600 / 4F (Locobase 10206)

Data from "Eight-Coupled Mineral Engine, Caledonian Railway", Locomotive Magazine, Volume VI (October 1901), p. 163. See also [], last accessed 28 July 2011; "Eight-coupled Mineral Engine: Caledonian Railway", Railway Engineer, Volume 22, No 9 (September 1901), p. 261; Charles Rous-Marten, "European Railway Jottings", Railway and Locomotive Engineering, Volume , No 11 (November 1901), p. 470.

This octet of large freight engines worked the Lanarkshire coal traffic. Their long wheelbases required special coupling (side) rods to accommodate the axles' lateral movements around tight curves. Unusual axle spacing consisted of the lead axle under the smokebox, a long gap to the middle two which reposed under the middle of the boiler, then another long gap to the last axle, which rolled under the very end of the frame.

The class introduced a four-valve safety valve bundle grouped on the firebox. In his R&LE report, Rous-Marten contended that this design would "minimize the risk" of disastrous explosions and "rendered as nearly impossible as is feasible by any means within our present knowledge."

According to steamindex: "They could haul 60 loaded wagons and were introduced together with 30 ton high capacity bogie wagons fitted with Westinghouse brakes." so a substantial trailing load. RE's 1901 report assessed the engine as "of very great power, and must represent almost the limit to which locomotive engineers can go, in this country at any rate, of simple engines."

The design was not repeated and the last of the class had been scrapped by 1921.