Tuesday, August 27, 2024

Is the Altar Stone the founding stone of Stonehenge?

You've got to be pretty motivated to bring a 6 ton lump of sandstone from the environs of the Orcadian Basin to Stonehenge (see The Scottish Stone article).

Let's, for the sake of argument, say that it's actually from Orkney. What else do we find there?

The list is pretty impressive, a few highlights are:

The Stones of Stennes - possibly the oldest "henge" monument in Britain - a henge being an enclosing earthwork with a bank on the outside and a ditch on the inside - with a 30m wide stone setting in the interior, oval in form with a central hearth. Roughly 5,100 years old.

The Ring of Brodgar - a perfectly circular stone circle 104m in diameter, within a bank and ditch (but with the ditch outside the bank, so not technically a "henge"). Roughly 4,500 years old.

Maes Howe - a chambered cairn and passage grave 35m in diameter, oriented to the setting Winter Solstice Sun. Roughly 4,800 years old.

Skara Brae - a settlement of ten stone-built houses that was discovered after a winter storm stripped the earth from a knoll in 1850 CE. Roughly 5,200 years old.

The Ness of Brodgar - sited on the spit of land between the Stones of Stennes and the Ring of Brodgar, this is a complex of stone-built structures that were first noticed in 2003 CE. Variously described as a "temple complex" or even a "university"(!), this is remarkable site with decorated, carved and painted walls and a striking artistic iconography. Roughly 5,500 years old, but deliberately closed down and abandoned after a huge feast in about 2,200 BCE.

The people inhabiting this region had to have been competent mariners - the strait separating Orkney from the mainland (the Pentland Firth) has some of the most powerful tides in the world.

Their origins are unclear, but Cunliffe, Renfrew, Collins, James, Prior and Oppenheimer all suggested that the arrival of a culture originating in the Iberian peninsular (perhaps emerging from the Mediterranean basin) and travelling by sea along the Atlantic western fringe of Europe is a possibility.

In Oppenheimer's 2006 book "The Origins of the British" he writes:

"...75-95% of British Isles (genetic) matches derive from Iberia... Ireland, coastal Wales, and central and west-coast Scotland are almost entirely made up from Iberian founders, while the rest of the non-English parts of the British Isles have similarly high rates. England has rather lower rates of Iberian types with marked heterogeneity, but no English sample has less than 58% of Iberian samples..."

If we look at the distribution of European megalithic structures, they closely match the supposed migration route of these people - from Malta via Iberia through Brittany and across to Cornwall, Wales, Ireland, the Isle of Man, western Scotland and the Hebrides to northern Scotland and Orkney.

Cultural artistic influences between Ireland and Orkney have been well documented by Sheridan - with a frequent back and forth of ideas, embellished at one location before returning to their source to re-influence subsequent expressions.

What is particularly interesting is the apparent diffusion of two specific aspects of Orcadian culture southwards through mainland Britain - the concept of "henging" and a style of pottery known as Grooved Ware. Thomas's paper on the topic of ceramics is well worth a read.

There was an obvious interest - perhaps obsession would be a better word - of the builders of these megalithic monuments with pointing them at key directions relating to the movements of the Sun and Moon over a development span of at least 2,000 years from the early 5th millennium BCE (in the case of the Locmariaquer complex) to the middle of the 3rd.

At the northernmost extreme of their range in Orkney, the rising and setting arcs along the horizons described by the Sun and the Moon are much greater than at their southern extreme around the Mediterranean.

For example, in 3000 BCE in Orkney (lat 59°N), the angle between summer and winter solstice sunrises is almost 105°, whereas in Malta (lat 36°N) it's only about 60°. The Moon's range at its Major Standstill is even greater - roughly 137° in Orkney versus 72° in Malta.

Without trying to suggest that people in the Neolithic had a concept of degrees, there's a very obvious difference between "obtuse" and "acute" angles.

... and there's a very obvious state that's exactly "between" these two - the right angle.

In Sweden there's a "stone boat" called Ales Stenar, which is oriented to the Winter Solstice Sunrise and Summer Solstice Sunset. It's at the latitude 55° 22′ 57″ N, which happens to be precisely where the angle between summer and winter solstice sunrise is 90°.

Ales Stenar's alignments

Work by Higginbottom on the astronomical alignments of Orcadian sites threw up some interesting observations, particularly with respect to the Stones of Stennes.

From the press release of Higginbottom's 2016 paper

There's an interest being demonstrated by the builders here in alignments to both the Moon and the Sun at their extreme positions, and the one that's drawn my attention is the Northernmost Moonset versus Winter Solstice Sunset. At this site the angle between these positions is roughly 115° in 3000 BCE.

Is it conceivable that they might have wanted to find a spot where this angle is the special one "between acute and obtuse"?

If so, then after working their way down Britain they'd have found it at the latitude of 51° 10' 44" - Stonehenge.

The Station Stone rectangle alignments

We moderns rediscovered this in the 1960s (see the article C.A. "Peter" Newham and the Station Stone Rectangle).

I realise that I am indulging in a huge amount of speculation here (but why not, it's fun!), but is it possible that a culture having a fascination with the sky and the movements of the Sun and Moon took it upon themselves to embark on the establishment of a monument at a location where they'd be able to bring the Sky to Earth with a supremely elegant design, using small locally sourced sarsen boulders to define the required rectangle?

Would they, perhaps, have brought a founding "anchor" stone from their ancestral homeland with them?

Where might they have installed it? Perhaps in line with the weird ridges and stripes in the landscape that pointed to the directions of the winter solstice sunset and summer solstice sunrise?

Perhaps where Atkinson suggested, in the stone hole immediately southwest of the later tallest trilithon?

Extract from "Stonehenge in its Landscape" Cleal et al 1995

Context for the extract from "Stonehenge in its Landscape"

Perhaps they set it upright but twisted it a bit so that its face could be sighted along in the direction of winter solstice sunrise and summer solstice sunset, while also being lit by the rising summer solstice and setting winter solstice Sun. A neat way to encode four directions with one stone.

Atkinson noted, having excavated around the Altar Stone in its present position, that one end had:

"clearly been dressed to an oblique bevelled outline"

which he felt might facilitate precise adjustment to its position when erected in its stonehole. 

They'd have had to twist it about 81° to the primary solstice axis - that being the angle between summer sunrise and winter sunrise at this latitude 5000 years ago.

If we accept Atkinson's suggestion that the Altar Stone once stood in the stonehole within WA 3639, then it's clear that it was subsequently moved to its present location - laying flat in front of the tallest trilithon (Stones 55, 56, 156 - now partly collapsed), most likely by the builders of the sarsen phase of the monument.

That new location is with its long axis directly under the secondary solstice alignment and with its centre being touched by the tip of the shadow of the Heelstone at summer solstice sunrise (see articles The Secondary Solstice Axis and The Shadow of the Heelstone)

We could imagine that relocating a stone of such pre-eminence on the site would have been controversial, even if its intended new position and orientation was chosen to retain that special significance.

The movers may have felt the need to appease their ancestors with an offering of some kind, and Atkinson found - within the primary fill of the empty stonehole, deliberately placed - just such a candidate, a large fragment of a polished Group I Cornish-provenanced greenstone axe.

In the small hollow in the stonehole to the bottom left of the ranging pole,
the polished greenstone axe fragment found by Atkinson

The polished greenstone axe fragment found in the stonehole of WA 3639 (2nd from left)

The authors (E.D. Evens et al) of the 1962 "Fourth Report of the Sub-Committee of the South-Western Group of Museums and Art Galleries on the Petrological Identification of Stone Axes" said, of the Group I samples:

"It is most closely matched by outcrops in the Mount's Bay region near Penzance, and the rock source might well be from a land surface now submerged. The possibility of locating this site by the methods of underwater archaeology should not be overlooked."

If the Stonehenge site was chosen by the Orcadians as the ideal spot to build their ultimate soli-lunar monument, and these five stones were then established (Altar Stone and Station Stones), the possibility exists for this having been the very earliest stone settings of Stonehenge - predating both the large sarsens, the small bluestones and perhaps even the surrounding earthwork bank and ditch and its associated cremation burials.

And so it could be that it was first established prior to 3100 BCE.

These five stones are sufficient to fix the Sky to the Earth.

Everything that came later simply reinforced and enhanced the original design.

Et in Orcadia, ego.

Update: September 12th 2024

In chasing down some references, I re-found Rodney Castleden's work "The Making of Stonehenge" (Routledge Press 1993, ISBN 0-415-08513-6) in which he identified the positioning of an upright Altar Stone in WA 3639 on the primary solstice axis. I felt I ought to acknowledge that he published and developed this idea first.