Single (locomotive)
Encyclopedia
Steam locomotive
A steam locomotive is a railway locomotive that produces its power through a steam engine. These locomotives are fueled by burning some combustible material, usually coal, wood or oil, to produce steam in a boiler, which drives the steam engine...
with a single pair of driving wheel
Driving wheel
On a steam locomotive, a driving wheel is a powered wheel which is driven by the locomotive's pistons...
s. Some sources use 'Single' only for the 2-2-2
2-2-2
Under the Whyte notation for the classification of steam locomotives, 2-2-2 represents the wheel arrangement of two leading wheels on one axle two powered driving wheels on one axle, and two trailing wheels on one axle. The wheel arrangement both provided more stability and enabled a larger firebox...
type, also known as a Jenny Lind locomotive
Jenny Lind locomotive
The Jenny Lind locomotive was the first of a class of ten steam locomotives built in 1847 for the London Brighton and South Coast Railway by E. B. Wilson and Company of Leeds, named after Jenny Lind who was a famous opera singer of the period...
, but more commonly singles could have any number of leading
Leading wheel
The leading wheel or leading axle of a steam locomotive is an unpowered wheel or axle located in front of the driving wheels. The axle or axles of the leading wheels are normally located in a truck...
or trailing wheel
Trailing wheel
On a steam locomotive, a trailing wheel or trailing axle is generally an unpowered wheel or axle located behind the driving wheels. The axle of the trailing wheels was usually located on a trailing truck...
s.