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.

Instilled with a good work ethic by his father, Thom taught himself industrial engineering and entered college in Glasgow in 1911 where he studied alongside John Logie Baird.

In 1912 he attended summer school at Loch Eck where he was trained in surveying and field astronomy by Dr David Clark and Professor Moncur.

Thom graduated from the Royal College of Science and Technology and the University of Glasgow in 1914, earning a BSc with special distinction in Engineering.

Thom helped to develop the Department of Aeronautics at the University of Glasgow and lectured on statistics, practical field surveying, theodolite design and astronomy.

[3] During the Second World War, Thom moved to Fleet in Hampshire where he was appointed Principal Scientific Officer heading the Royal Aircraft Establishment team that developed the first high speed wind tunnel.

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.

From around 1933 to 1977 Thom spent most of his weekends and holiday periods hefting theodolites and survey equipment around the countryside with his family member or friends, most notably with his son Archie.

Thom went on to identify numerous solar and stellar alignments at stone circles, providing the foundations for the scientific discipline of archaeoastronomy.

Thom's suggested megalithic solar year was divided by midsummer, midwinter, and the two equinoxes into four and then subdivided into eight by early versions of the modern Christian festivals of Whitsun, Lammas, Martinmas, and Candlemas (see Scottish Quarter Days).

Thom's proposed length for the Megalithic yard has been reused as such in several controversial books that claim this unit of measurement is a subdivision of the Earth's circumference in an alleged 366-degree geometry.

[23] Nevertheless, Thom's legacy remains strong, Krupp wrote in 1979, "Almost singlehandedly he has established the standards for archaeoastronomical fieldwork and interpretation, and his amazing results have stirred controversy during the last three decades."

[12] In his book Genes, Giants, Monsters and Men, Joseph P. Farrell states, "If Thom was right, the development of human civilization may have to be rewritten!"