Alexander Allan (locomotive engineer)

Alexander Allan
Born	1809 Montrose, Angus
Died	2 June 1891 Scarborough, Yorkshire
Nationality	Scottish
Engineering career
Engineering discipline	Mechanical engineering

Allan valve gear, seen here fitted to an early Austrian locomotive

Alexander Allan was a Scottish mechanical engineer. He was born at Montrose, Angus, in 1809 and died at Scarborough, Yorkshire on 2 June 1891.

Career

From 1843 to 1853 he was Works Manager at the Crewe Works of the Grand Junction Railway, later London and North Western Railway, under Francis Trevithick. He later claimed the credit for designing the Crewe type locomotive with inclined cylinders and double frames, but this claim has been challenged. From 1853 to 1865 he was Locomotive Superintendent of the Scottish Central Railway. Allan was an original member of the Institution of Mechanical Engineers in 1847.

Inventions

Allan made a number of inventions, including a balanced slide valve, but the best-known is his straight-link valve gear of 1855.

See also

• George Forrester and Company
• Locomotives of the London and North Western Railway

Sources

• London and North Western Railway Society
• Stuart, D. H. & Reed, Brian: The Crewe Type (Loco Profile No 15), 1971.

Preceded by Robert Sinclair

Locomotive Superintendent of Scottish Central Railway 1854-1865

Succeeded by Post abolished when S.C.R. absorbed by Caledonian Railway