Pioneering railway engineer and politician. Born in Ayr, the son of a builder and wright, Miller was educated at Ayr Academy. He began his career in a solicitor's office in Ayr but soon decided to train as a land surveyor. He studied at the University of Edinburgh. Having worked for Thomas Grainger for two years, he became his partner in the Edinburgh firm of Grainger & Miller in 1825, specialising in planning railway lines. He was appointed Chief Engineer by various companies, including the Dundee and Arbroath Railway, the Glasgow, Paisley, Ayr and Kilmarnock Railway and the Edinburgh and Glasgow Railway, and grew wealthy as a result of this work. He was elected a Fellow of the Royal Society of Edinburgh in 1841.
He retired in 1850 and set to work improving his estates at Millfield and Parkhill in Stirlingshire, and buying further properties; namely Leithen Hopes in Peeblesshire and Drumlithie in Kincardineshire. He also served as Liberal Member of Parliament for Edinburgh (1868-74). Miller died in Edinburgh, leaving a substantial estate, and is buried in Dean Cemetery. He remembered by a plaque in Haymarket Station, unveiled on the centenary of his death.