Alexander Thom

Alexander Thom ( born March 26, 1894 in Mains Carradale, Argyll, Scotland, † November 7, 1985 in Fort William, Scotland ) was a Scottish engineer scientists and amateur archaeologist ( archaeoastronomy ).


He studied at the University of Glasgow, where he was also a lecturer from 1922 to 1939. From 1945 to 1961 he was professor of engineering at Oxford. Since 1934 he was interested in prehistoric stone circles. He is best known for the theory of megalithic yards, the length of which is the construction of many megalithic monuments are based. Alexander Thom calculated this quantity from many megalithic 82.9 cm. For the first time the size of the megalithic yard in 1955 was published in the article A statistical examination of megalithic sites in Britain in the Journal of the Royal Statistical Society. After his retirement he published in 1962 and 1964 in the same journal two more articles on this topic. In addition to the system of measurement Thom developed a theory of megalithic stone circles. He classified into six types: true circles, ellipses, two types of egg-shaped circles and two types of flattened circles. In addition, he developed a theory of the so-called Megalithic calendar.


Thom's theories encountered in the archaeological experts on contradiction, but were enthusiastically received by parts of the New Age movement of the 1960s. Similar to Gerald Hawkins interpretation of Stonehenge as astronomical " computer " Thoms were brought ideas to the supposedly lost knowledge of extinct cultures in conjunction. Thom even regretted this, because his work thus came the reputation of pseudoscience or has been interpreted.

The astronomical orientation of many megalithic stone circles is nowadays doubted any more. Thom's megalithic yard is scientifically, however, still controversial.


  • Alexander Thom Megalithic Sites in Britain. Clarendon Press, Oxford 1967, 1976, 1979. ISBN 0-19-813148-8
  • Alexander Thom Megalithic Lunar Observatories. Clarendon Press, Oxford 1971, 1978. ISBN 0-19-858132-7
  • Engineering scientists
  • Historians of science
  • University teachers (Oxford)
  • University teachers ( University of Glasgow )
  • Briton
  • Scotsman
  • Born 1894
  • Died in 1985
  • Man