Stone Circles and Megalithic Mathematics.

Abstract

Thom has proposed that megalithic monuments were planned using geometry and a unit of length — the megalithic yard. All data in Thom's data-sets not deriving from well-preserved stone circles are removed, so that these proposals can be tested on this one category of monument. The statistical evidence for the existence of the megalithic yard is found to be equivocal. The shapes of stone rings, a part from the true circle, can be most easily explained as arising from layout by eye, without geometric planning. Exceptionally, two groups of stone circles which have distinctive architectural traits appear to have been planned to be truly circular, presumably using peg and rope construction. These groups are in southern England and north-east Scotland, although the latter group is not identified with certainty.