{{Short description|Locomotive wheel arrangement}} [[File:LNWR Webb Experiment 1120 Apollo.jpg|thumb|[[LNWR Webb Experiment Class|LNWR Webb ''Experiment'' class]] 1120 ''Apollo'': one carrying axle and two driving axles]] [[File:LNWR 2+2-2-0 No 189 at Curzon Street, Birmingham, circa 1859.jpg|thumb|LNWR 2+2-2-0 No 189 at [[Birmingham Curzon Street railway station (1838–1966)|Curzon Street, Birmingham]], circa 1859: two carrying axles, one driving axle]] Under the [[Whyte notation]] for the classification of [[steam locomotive]]s, '''2-2-2-0''' usually represents the [[wheel arrangement]] of two [[leading wheel]]s on one axle, four powered but uncoupled [[driving wheel]]s on two axles, and no [[trailing wheel]]s, but can also be used to represent two sets of leading wheels (not in a [[bogie]]) two [[driving wheel]]s, and no [[trailing wheel]]s. Some authorities place brackets around the duplicated but uncoupled wheels, creating a notation 2-(2-2)-0,<ref name=Baxter1>{{cite book| last = Baxter | first = Bertram | title =British locomotive catalogue 1825-1923 | publisher = Moorland Publishing | volume =1 | year =1977 | location =Buxton | pages= 12 | isbn =978-0-903485-50-0}}</ref> or (2-2)-2-0,<ref>Baxter, pp.45 & 67.</ref> as a means of differentiating between them. Others simply refer to the locomotives 2-2-2-0.<ref name=Casserley>{{cite book| last = Casserley | first = H.C. | title = Historic locomotive pocket book | place = London | publisher = Batsford | year = 1960 | pages = 51}}</ref>
==Usage== The 2-2-2-0 wheel arrangement was first used on some locomotives introduced on the [[Eastern Counties Railway]] by [[John Chester Craven]] between 1845 and 1847, and some [[Crampton locomotive]]s on the [[South Eastern Railway, UK|South Eastern Railway]] in 1849.<ref>Baxter, (1977) pp.45 & 67.</ref> However the 2-2-2-0 type is usually associated with [[Francis Webb (engineer)|Francis Webb]] of the [[London and North Western Railway]] who between 1882 and 1890 introduced a number of [[compound locomotive]] classes including the [[LNWR Webb Experiment Class]], [[LNWR Dreadnought Class]] and [[LNWR Teutonic Class]]. The locomotives were never reliable and Webb's successor [[George Whale]] withdrew them all within three years of taking up office in 1903.<ref name=Baxter2b>{{cite book | last = Baxter | first =Bertram | title='British locomotive catalogue 1825-1923 | publisher = Moorland Publishing | volume =2b | year =1979 | location =Buxton | pages= 196 | isbn =0-903485-84-2}}</ref> The [[Pennsylvania Railroad]] had [[Pennsylvania Railroad no. 1320|one engine]] based on the LNWR compounds which proved to be underpowered and was scrapped in 1897. The type was used with more success on French railways with a 4-cylinder [[compound locomotive]] designed by [[Alfred de Glehn]], of the [[Société Alsacienne de Constructions Mécaniques]] (SACM) in 1885. One [[Nord 2.121 to 2.180|later example]] was of the [[4-2-2-0]] configuration but it was eventually rebuilt as a [[4-4-0]] instead.<ref>{{cite web|lang=fr|author=Roland Arzul|title=Les locomotives 220 type Nord de la Compagnie de l'Etat|url=http://roland.arzul.pagesperso-orange.fr/materiel/traction/220b.htm|date=15 December 2008|archive-url=https://web.archive.org/web/20231002160605/http://roland.arzul.pagesperso-orange.fr/materiel/traction/220b.htm |accessdate=2 November 2023|archive-date=2023-10-02 }}.</ref>
==References== {{reflist}}
{{Whyte types}}
[[Category:2-2-2-0 locomotives| ]] [[Category:Whyte notation|2-2-2-0]]