Alexander Thom

Alexander Thom (26 March 1894 – 7 November 1985) was a Scottish engineer most famous for his theory of the Megalithic yard, categorisation of stone circles and his studies of Stonehenge and other archaeological sites.

Later, he was professor and chair of engineering science at Brasenose College, University of Oxford where he became interested in the methods that prehistoric peoples used to build megalithic monuments. Thom became especially interested in the stone circles of the British Isles and France and their astronomical associations.