The wheel diameter is effectively the "gear ratio" of a steam engine, and large driving wheels delivered the high linear tyre speed needed for fast locomotives, whilst keeping the axle bearing and piston speeds low enough to remain within the limits of the existing technology.

Later on, increasing engine power would require better adhesion than a single pair of driving wheels could provide, but that was not a problem at the time.

Cramptons were most popular in France and Germany, but some were also used in England, by companies including the London and North Western Railway (LNWR).

Although the locomotive was fast and capable of working heavy trains for long distances, its oversized frame caused damage to the track.

Francis had moved north to become resident engineer, then Locomotive Superintendent of the Grand Junction Railway (GJR) (later formed into the LNWR).

Cornwall was an attempt to avoid the damaging long wheelbase of the Cramptons, whilst still permitting large driving wheels.

The Railway Gazette,[5] cited in Ahrons,[2] suggests that there was an even earlier design for Cornwall, as a 2-2-2 with single 4 ft wheels both forward and back.

If constructed like this, the likelihood is that it would suffer the same problems as its contemporary, Gooch's first 2-2-2 Great Western class of 1846, where a broken front axle led to re-design as a 4-2-2.

Another minor rebuild in the 1870s provided a typically LNWR style of cab, with a short roof and semi-open sides.

In the mid 1980s, Cornwall was repainted by the National Railway Museum and air freighted to Japan for exhibition and later returned to Crewe.