William Ernest Dalby, FRS (21 December 1862 – 25 June 1936) was a British engineer. At the age of 14 he started work in the Stratford Locomotive Works of the Great Eastern Railway. In 1884 he moved to work in the Crewe Works of the London and North Western Railway as Chief Assistant in the Permanent Way Department. he studied in his spare time for a BSc degree at London University. He was Vice-President of both the Institute of Mechanical Engineers and the Institution of Civil Engineers. In 1913 he was elected a Fellow of the Royal Society He died at his home in Ealing, London