Douglas Earle Marsh (1862–1933) was an English railway engineer, and was the Locomotive, Carriage and Wagon Superintendent of theLondon, Brighton and South Coast Railway from November 1904 until his early retirement on health grounds in July 1911.

Marsh was born atAylsham,Norfolk on 4 January 1862, and was educated atBrighton College andUniversity College London. He worked for theGreat Western Railway underWilliam Dean becoming an Assistant Works Manager atSwindon in 1888. In 1896 he became Chief Assistant Mechanical Engineer of theGreat Northern Railway atDoncaster railway works underH.A. Ivatt, where he participated in the design of theIvatt Atlantics.^[1]

Marsh succeededR. J. Billinton as the Locomotive, Carriage and Wagon Superintendent atBrighton Works on 23 November 1904.^[2] Marsh's locomotive classes included two designs of Atlantic 4-4-2 (H1 Class andH2 Class), and four designs of4-4-2T (I1,I2,I3, andI4). In 1910 he designed two 4-6-2T tank locomotives of theJ1 and J2 classes. His least successful design was theLB&SCR C3 class0-6-0 freight locomotives.

Marsh also rebuilt many of his predecessors' locomotives with larger boilers thereby creating theA1X,B2X,C2X,E4X,E5X andE6X classes. In 1907 he introduced an example of theSchmidt superheater on one of hisLB&SCR I3 class locomotives, with dramatically improved results. Whilst at Brighton he abolished theStroudley yellow livery for passenger locomotives and removed the names from them.

During Marsh's period in officeBrighton railway works built up a serious backlog of locomotives awaiting repair, and by 1910 30% of the locomotive stock was unusable.^[3] Marsh received much of the blame for this, although it was partly because the works was overwhelmed at the time.

Marsh was never popular within the workforce at Brighton. He resigned on the grounds of deteriorating health in July 1911, following accusations of a number of irregularities in his accounting.^[4] Shortly after his resignation he became a consulting engineer for theRio Tinto Company until 1932. He died inBath in May 1933.

• GB191028252, published 30 November 1911, Improvements in and relating to systems and apparatus for washing out and filling locomotive boilers and the like^[5]

• D.L. Bradley,Locomotives of the LB&SCR, Parts II. and III.Railway Correspondence and Travel Society, 1972.

, 1978.

• Klaus Marx, Douglas Earle Marsh: his life and times. Oakwood Press, 2005.

• 1862 births
• 1933 deaths
• English engineers
• Locomotive builders and designers
• Locomotive superintendents
• London, Brighton and South Coast Railway people
• English railway mechanical engineers
• People from Aylsham

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