Geared steam locomotive
This gearing is part of the machinery within the locomotive and should not be confused with the pinion that propels a rack locomotive along the rack between the rails. The geared steam locomotives that have been built have been for conventional track, relying on the adhesion between wheels and rail.
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.