Archaeoastronomy in the British Isles - The Stones and the Stars: Building Scotland's Newest Megalith - page 94

However, what sells the pass completely is the comment
about the builders' practical experience in laying out right-angled
triangles. Thom deduced their existence by working back from
the positions of the stones to the geometrical principles of their
layout, and he didn't suggest that those principles were arrived at
by anything other than practical experience. But the experience,
in this context, is in the art of laying out large rings in integral
multiples of a standard unit of length; in other words, if the lay-
outs are based on right-angled triangles, then the layers-out must
have been “into” numerology, and the numbers they manipulated
must have been numbers of something - paces, foot-lengths, arm-
lengths, lengths of rope or measuring rods.
Thom maintained that the layout of a large number of sites
in megalithic yards, up and down the country, was so precise that
measuring rods must have been used, and the rods must have been
virtually identical, so much so that they must all have been cut
to a single standard rather than copied one from another. Compar-
ing the values of the megalithic yard in Brittany and Orkney, for
example, the Thoms found discrepancies of only one part in 1,000
[ 17 ] . The dispute rested on mathematics, on the one hand, and on
the absence of evidence for such an organized society on the other.
It was to that apparent lack of absence of evidence that Thom's
critics most often referred when they spoke of the archaeological
facts - but see below.
When John Braithwaite joined the Astronomy Project in
the summer of 1978, he was asked to check out the megalithic
yard, because he had a grounding in the relevant math. Having
trained in business studies at the University of Strathclyde, he had
worked for major companies such as Charles Frank Limited and
the defense contractors, Avimo; after the project he went on to
found his own company, Dalserf Optics (later Braithwaite Tele-
scopes), which became Scotland's only telescope manufacturer in
the 1990s and remained so until his untimely death in 2012.
Braithwaite came back with “a tip of the hat” to Thom's
methods and more than a little irked by Thom's critics. One
such had apparently maintained that the whole thing was spu-
rious because the measurements disagreed with the megalithic
yard ideal by as much as one part in 1,500. Arming himself with
the plans, Braithwaite had measured his own modern house and