4-8-0

4-8-0 (Twelve-wheeler ^[1][2])

Front of locomotive at left

The Centipede as built (bottom) and as modified by the B&O Railroad (top)

Equivalent classifications UIC class 2′D French class 240 Turkish class 46 Swiss class 4/6 Russian class 2-4-0

First known tank engine version First use 1909 Country United Kingdom Locomotive NER Class X Railway North Eastern Railway Designer Wilson Worsdell Builder North Eastern Railway

First known tender engine version First use 1855 Country United States of America Locomotive B&O no. 235 Centipede Railway Baltimore and Ohio Railroad Designer Ross Winans Builder Ross Winans

First known "True type" version First use 1882 Country United States Locomotive 229 Mastodon Railway Central Pacific Railroad Designer Andrew Jackson Stevens Builder Central Pacific Sacramento shops Evolved from 2-8-0 Evolved to 4-8-2 Benefits Better power than 2-8-0 Drawbacks Small firebox

Under the Whyte notation for the classification of steam locomotives, 4-8-0 represents the wheel arrangement of four leading wheels on two axles, usually in a leading truck or bogie, eight powered and coupled driving wheels on four axles and no trailing wheels. In North America and in some other countries the type was usually known as the Twelve-wheeler.^[1][2]