THE excitement of Christopher Bruce about the Ness of Brodgar (Letters, Mar 7) is shared by myself and should be by everybody. The proposal that the site should be protected by a permanent building which would allow for further examination and marking of this world-ranking site must be taken up by the Scottish Government and the Scottish public with vigour.

This site predates Stonehenge and the multitude of such constructions that stretch from Orkney to New Grange in Ireland and Carnac in France, and it may be come to be seen as the progenitor. The people who built it were skilled in calculation of astronomy, as Christopher Bruce describes.

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The late Professor Thom gives us another connection to this ancient world. This Scot in his retirement surveyed numerous stone circles and established that they were based on a standard size he called the megalithic yard. The accuracy of this implied much more than common culture, but the possibility that they used a basic dimension, namely the diameter of the earth, worked out by the constructors of the circles. An understanding of astronomy would lead to such knowledge.

A monument to such early sophistication must be constructed at the Ness of Brodgar.

Iain WD Forde