Editing 2-8-4 (section)

{{Short description|Locomotive wheel arrangement}}
{{Infobox steam wheel arrangement
| name             = 2-8-4 (Berkshire)
| image            = WheelArrangement 2-8-4.svg
| alt              = Diagram of one small leading wheel, four large driving wheels joined by a coupling rod, and two small trailing wheels
| caption          = Front of locomotive at left
| image2           = Hilliard Towers Apartments Chicago Nickel Plate 765-0560.jpg
| alt2             = 
| caption2         = [[Nickel Plate Road 765]], a typical American 2-8-4, on an excursion train ca. 2018
<!--Equivalent classifications-->
| hatnote          = 
| UIC/Germany/Italy= 1′D2′
| French/Spanish   = 142
| Turkish          = 47
| Swiss            = 4/7
| Russian          = 1-4-2
<!--First known tank engine version-->
| date             = 1893
| country          = Australia
| locomotive       = [[WAGR K class]]
| railway          = [[Western Australian Government Railways]]
| designer         = [[Neilson and Company]]
| builder          = Neilson and Company
| evolvedfrom      = [[2-8-2|2-8-2T]]
| evolvedto        = 
| mainbenefit      = Larger fireboxes and coal bunkers
| maindrawback     = 
<!--First known tender engine version-->
| date2            = 1925
| country2         = United States of America
| locomotive2      = B&A class A1
| railway2         = [[Boston and Albany Railroad]]
| designer2        = [[Lima Locomotive Works]]
| builder2         = Lima Locomotive Works
| evolvedfrom2     = [[2-8-2]]
| evolvedto2       = 
| mainbenefit2     = Larger firebox than 2-8-2
| maindrawback2    = 
<!--First known "True type" version-->
| date3            = 
| country3         = 
| locomotive3      = 
| railway3         = 
| designer3        = 
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| evolvedfrom3     = 
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}}

Under the [[Whyte notation]], a '''2-8-4''' is a [[steam locomotive]] that has two unpowered [[leading wheel]]s, followed by eight coupled and powered  [[driving wheel]]s, and four [[trailing wheel]]s. This locomotive type is most often referred to as a '''Berkshire''', though the [[Chesapeake and Ohio Railway]] used the name [[Chesapeake and Ohio class K-4|Kanawha]] for their 2-8-4s. In Europe, this [[wheel arrangement]] was mostly seen in mainline passenger express locomotives and, in certain countries, in [[tank locomotive]]s.
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