Geared steam locomotive
A geared steam locomotive is a type of steam locomotive which uses gearing, usually reduction gearing, in the drivetrain, as opposed to the common directly driven design.
Steam locomotives of Ireland
Note that narrow gauge locomotive classes included the letter N after the prefix letter, letter C was also used for Bo-Bo diesels, and that letters B, C, D, F, J, and K were used for the same wheel arrangements by the London and North Eastern Railway, while E and G changed places.