Megalithic Astronomy
Whilst I was still at school I became interested in what has been
described
as "megalithic astronomy" - the astronomy of standing stones. This had
been taken forward with some complexity by Prof. Alexander Thom, an
Engineering professor in Oxford. My interest was initially as a result
of seeing a television programme about his work on the subject - I
eventually tracked down that it was a "Chronicle" programme, Cracking the
Stone Age Code, shown in 1970. There's a recent
commentary on Prof. Thom here.
I even remember talking about my fascination with this when I had my entrance interview at Trinity College - I had already visited and taken notes and simple survey information at a few sites in North Wales.
At Cambridge I met a few other people in CUAS interested in this
fascinating subject - was there any basis for Thom's ideas about
complex astronomical functions of the megalithic sites, or not? By the
end of my first year we had organised a little expedition to the
Kintyre area in Scotland, and Douglas Heggie, then
a fellow of the college and also interested in the subject, suggested
that we do some real surveying. We borrowed a theodolite from the
Engineering department, and it took off from there!
We had a lot of fun with the expedition and the success with the
paper, so further expeditions followed. I missed the one to Mull
because I had to sort out problems relating to my PhD studentship for
the following year - but joined the expedition to Lewis and Harris
later in the summer, when we proposed to work on the sites around
Callanish. We were never really interested in Thom's ideas about the
"megalithic yard" as a unit of measurement; it was the astronomical
connection that fascinated us.
Callanish 1975
My photos from the Callanish trip are in black and white - I used to
do all my own processing in those days, and we wanted prints to tie in
with surveys of horizon profiles. Home processed black and white was
also a lot cheaper than colour slides. There was no shop and tourist
stuff in those days - though the site was visited by quite a few people
during the time we spent surveying.
For some reason we went through a lot of "brown sauce" at the
Laxdale camp site where we were camped for the trip - hence this photo
I suppose.
The weather was not always beautifully sunny, but provided the
horizon was clear we could survey horizon profiles. The umbrella is
more for the protection of the theodolite rather than the surveyor!
We wanted to be able to discover if our surveyed horizon profiles
could have been used for astronomical purposes. This meant that we
needed to know the azimuth of our
surveys accurately, and we relied on solar observations to determine
this,
in conjunction with an accurate time (from the 60kHz signal then
transmitted from MSF Rugby). Guy G3ZHL built the time signal
receiver.
Here's the theodolite being used to project an image of the sun,
together with the crosshairs, and a stopwatch held ready to catch each
limb of the Sun crossing the wires. The time was checked immediately
afterwards using a 60kHz receiver for the time signal service.
We didn't just do surveying - we managed to tour around Lewis and
Harris, visiting Carloway Broch, and did an ascent of Clisham in the
mist. We also did a long walk in to Rainigadale, Harris - in those days
there was no real road in to the settlement.
The survey results for this expedition were published as a paper in
the Journal for the History
of Astronomy, "Indicated declinations at the Callanish megalithic
sites". This didn't include the drawings of the surveyed profiles, but
I do still have a copy of them.
The Uists 1977
This was a good follow-up to the Callanish expedition - lots of
surveying, though rather more of a holiday. Look at the prone bodies in
the photo above - and it looks as though the wind is even blowing the
stone over! The weather was extremely windy at times - one rather
flimsy "Mediterranean" style tent collapsed in a gale overnight. We had
some interesting experiences from Callanish and its surrounding sites
so made sure that we had permission to survey in lots of remote places.
Here's the expedition photo.
Islay and Jura 1978
Islay is extensively farmed, with big estates, so a lot of effort
went into contacting factors to get permission to survey. No wild
camping either here - our tent village was on a little camp site
complete with touring caravans. By this stage I had my radio amateur
licence as GM8OTI, so we were able to use radio communications over
sight lines using a couple of portable 2m FM sets I had built. The
GM3ZHL HF antenna mast is visible in the photo above. As well as
visiting Islay and surveying sites, we made a trip over to Jura,
principally to make an ascent of the Paps of Jura.
Another expedition photo. Lots of people there for the holiday, as
well as the keen surveyors!
We had a lot of fun with the megalithic astronomy expeditions, they
made great holidays in lovely areas with fantastic scenery. We went our
separate ways in our chosen careers (mostly in astronomy) and only Clive Ruggles eventually
turned the subject into his job! The work on the Uists and Isaly and
Jura wasn't wasted, Clive pulled it all together in a big collection of
the work done across western Scotland, and published in the BAR series
in 1984.
Later ...
The stones are still there - this is the big menhir at Loch Nell
near Oban, one of the sites surveyed for our first paper; a burial
cairn is in the foreground. I took this photo many years later, when we
had a caravan near Oban.
Eventually I also managed to visit the stone alignments at Carnac in
Brittany. These are so spectacular - the enormously long avenues of
hundreds of stones are quite different in scale to the Scottish sites.
Alexander Thom's books
The books that really got me interested in the subject were
published a long time ago:
Megalithic Sites in Britain, Oxford, 1967
Megalithic Lunar Observatories, Oxford, 1971