Editing 4-4-0 (section)

== Development ==

===American development===
Five years after new locomotive construction had begun at the [[West Point Foundry]] in the United States with the {{whyte|0-4-0}} ''[[Best Friend of Charleston]]'' in 1831, the first 4-4-0 locomotive was designed by [[Henry Roe Campbell|Henry R. Campbell]], at the time the chief [[engineer]] for the Philadelphia, Germantown and Norristown Railway. Campbell received a [[patent]] for the design in February 1836 and soon set to work building the first 4-4-0.<ref name="White"/>

At the time, Campbell's 4-4-0 was a giant among locomotives. Its [[cylinder (engine)|cylinder]]s had a {{convert|14|in|adj=on}} bore with a {{convert|16|in|adj=on}} [[piston]] stroke, it boasted {{convert|54|in||adj=mid|-diameter}} driving wheels, could maintain {{cvt|90|psi}} of steam [[pressure]] and weighed {{convert|12|ST|t}}. Campbell's locomotive was estimated to be able to pull a train of {{convert|450|ST|t}} at {{cvt|15|mph|km/h}} on level track, outperforming the strongest of [[Baldwin Locomotive Works|Baldwin's]] {{whyte|4-2-0}}s in tractive effort by about 63%. However, the frame and driving gear of his locomotive proved to be too rigid for the railroads of the time, which caused Campbell's prototype to be [[derailment]]-prone. The most obvious cause was the lack of a weight equalizing system for the drivers.<ref name="White"/>

[[File:440woodcut.jpg|thumb|An 1880s woodcut of a {{nowrap|4-4-0}} locomotive]]
At about the same time as Campbell was building his 4-4-0, the company of Eastwick and Harrison was building its own version of the 4-4-0. This locomotive, named ''Hercules'', was completed in 1837 for the [[Lehigh Valley Railroad#1850-1860|Beaver Meadow Railroad]]. It was built with a leading bogie that was separate from the locomotive frame, making it much more suitable for the tight curves and quick grade changes of early railroads. The ''Hercules'' initially suffered from poor tracking, which was corrected by giving it an effective springing system when returned to its builder for remodeling.<ref name="White"/>

[[File:HABS - Norris Locomotive Works stone at the Washington Monument (cropped).jpg|thumb|right|1856 relief sculpture of a 4-4-0 commissioned by the Norris Locomotive Works, depicting an early model prior to the adoption of the covered cab]]
[[File:Richmond & Petersburg Railroad 02705r.jpg|thumb|right|Remains of a 4-4-0 locomotive of the [[Richmond & Petersburg Railroad]], Richmond Virginia 1865]]

Even though the ''Hercules'' and its successors from Eastwick and Harrison proved the viability of the new wheel arrangement, the company remained the sole builders of this type of locomotive for another two years. [[Norris Locomotive Works]] built that company's first 4-4-0 in 1839, followed by [[Rogers Locomotive & Machine Works]], the Locks & Canals Machine Shop and the Newcastle Manufacturing Company in 1840. After Henry Campbell sued other manufacturers and railroads for infringing on his patent, [[Baldwin Locomotive Works|Baldwin]] settled with him in 1845 by purchasing a license to build {{whyte|4-4-0s}}.<ref name="White"/>

[[File:Atlantic & St. Lawrence Railroad Locomotive.jpg|thumb|Short wheelbased [[St Lawrence & Atlantic Railroad]] ''Coos'', c. 1856, Longueuil, Quebec]]
As the 1840s progressed, the design of the 4-4-0 changed little, but the dimensions of a typical example of this type increased. The [[boiler]] was lengthened, drivers grew in diameter and the firegrate was increased in area. Early {{whyte|4-4-0s}} were short enough that it was most practical to connect the pistons to the rear drivers, but as the boiler was lengthened, the [[connecting rod]]s were more frequently connected to the front drivers.<ref name="White"/>

In the 1850s, locomotive manufacturers began extending the wheelbase of the leading bogie and the drivers as well as the tender bogies. By placing the axles farther apart, manufacturers were able to mount a wider boiler completely above the wheels that extended beyond the sides of the wheels. This gave newer locomotives increased heating and steaming capacity, which translated to higher tractive effort.  Similarly, by placing the leading bogie axles further apart enabled the cylinders to be placed between them in a more horizontal orientation, thereby distributing the engine's weight more evenly when going around curves and uneven track.  These advancements, combined with the increasingly widespread adaptation of cowcatchers, bells, and headlights, gave the 4-4-0 locomotives the appearance for which they are most recognized.<ref name="White"/>

The design and subsequent improvements of the 4-4-0 configuration proved so successful that, by 1872, 60% of Baldwin's locomotive construction was of this type and it is estimated that 85% of all locomotives in operation in the United States were {{nowrap|4-4-0}}s. However, the 4-4-0 was soon supplanted by bigger designs, like the {{whyte|2-6-0}} and {{whyte|2-8-0}}, even though the 4-4-0 wheel arrangement was still favored for express services. The widespread adoption of the {{whyte|4-6-0}} and larger locomotives eventually helped seal its fate as a product of the past.<ref name="White"/>

Although largely superseded in North American service by the early 20th century, [[Baldwin Locomotive Works]] produced two examples for the [[narrow gauge]] [[Ferrocarriles Unidos de Yucatán]] in early 1946, probably the last engines of this wheel arrangement intended for general use.<ref>''[[Trains (magazine)|Trains]]'' magazine, June 1946</ref> A number of individual engines have been custom-built for [[theme park]]s in recent years, resembling early designs in appearance.

===British development===
The first British locomotives to use this wheel arrangement were the {{RailGauge|7ft0.25in}} [[broad gauge]] 4-4-0 [[tank engine]] designs which appeared from 1849. The first British [[tender (rail)|tender locomotive]] class, although of limited success, was the broad gauge [[GWR Waverley Class|''Waverley'' class]] of the [[Great Western Railway]], designed by [[Daniel Gooch]] and built by [[Robert Stephenson & Company]] in 1855.<ref>{{cite web| url=http://www.laluciole.net/gwr/gwr04a-goochlocos.html| title=A history of Britain's broad gauge railways| author=Richard Marshall| access-date=2010-05-02| archive-url=https://web.archive.org/web/20110723175326/http://www.laluciole.net/gwr/gwr04a-goochlocos.html| archive-date=2011-07-23| url-status=usurped}}</ref>

The first American-style British 4-4-0 tender locomotive on {{RailGauge|4ft8.5in|al=on|allk=on}}, designed by [[William Bouch]] for the [[Stockton & Darlington Railway]] in 1860, followed American practice with two [[Cylinder (locomotive)#Outside cylinders|outside cylinders]].<ref>{{cite web| url=http://www.lner.info/eng/bouch.shtml| title=The London & North Eastern Railway (LNER) Encyclopedia - William Bouch| last=Marsden  |first=Richard| access-date=2007-06-11| archive-url= https://web.archive.org/web/20070707043646/http://www.lner.info/eng/bouch.shtml| archive-date= 7 July 2007 | url-status= live}}</ref>

Britain's major contribution to the development of the 4-4-0 wheel arrangement was the [[Cylinder (locomotive)#Inside cylinders|inside cylinder]] version, which resulted in a steadier locomotive, less prone to oscillation at speed. This type was introduced in Scotland in 1871 by [[Thomas Wheatley (locomotive engineer)|Thomas Wheatley]] of the [[North British Railway]].<ref name="Poultney">{{cite book
  | last = Poultney | first = Edward Cecil  |authorlink=Edward Cecil Poultney
  | title = British express locomotive development 1896-1948 | publisher = [[Allen & Unwin]] | year = 1952 | location = London | pages = 56–65
}}</ref>