2-8-0 Definition
    noun
  
 Under the Whyte notation system, a steam locomotive that has a single-axle leading truck followed by four powered driving axles, and no trailing wheels. It's popular name is "Consolidation" as its appearance coincided with the consolidation of several Eastern coal railroads. The Consolidation was extremely popular, especially in the first quarter of the 20th century.
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Under the Whyte notation system, a steam locomotive that has two leading wheels, four pairs of coupled driving wheels, and two trailing wheels.
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Under the Whyte notation system, a steam locomotive that has two leading wheels arranged in a leading truck, eight coupled driving wheels and four trailing wheels in a trailing truck.
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Under the Whyte notation system, a steam locomotive that has two leading wheels, eight coupled driving wheels, and six trailing wheels.
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