2-4-0

2-4-0 (Porter)

Front of locomotive at left

LSWR 0298 Class or Beattie Well Tank

Equivalent classifications UIC class 1B, 1'B French class 120 Turkish class 23 Swiss class 2/3 Russian class 1-2-0

First known tender engine version First use c. 1830s-1840s Country United Kingdom Evolved from 2-2-0 & 2-2-2 Benefits Better adhesion with coupled wheels

Under the Whyte notation for the classification of steam locomotives, 2-4-0 represents the wheel arrangement of two leading wheels on one axle, four powered and coupled driving wheels on two axles and no trailing wheels. In most of North America it became known as a Porter.

The notation 2-4-0T indicates a tank locomotive of this wheel arrangement, on which its water and fuel is carried on board the engine itself, rather than in an attached tender. A subset is 2-4-0WT, a configuration in which the water is under the bolier in a well tank.