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.
DRG locomotive classification
The renumbering of electric locomotives followed in 1926/1927 and used a similar scheme as that employed for the steam locomotives, with a main class number and a serial number. They were distinguished from steam locomotives by a preceding letter "E". The engines were arranged according to top speed and the number of driven and carrying axles.If the characteristics and design were otherwise the same, locomotives with a side-rod drive were given lower class numbers than those with individually driven axles.