One of the "high crags" of Preseli -- this one is on Foel Drygarn
As a result of some interesting recent correspondence with a knowledgeable reader of my latest article in "The Holocene", I have been thinking afresh about the manner in which the bluestone tors of Preseli don't just dominate the upland landscape, but also dominate the debate about Stonehenge. Ever since 1923, when HH Thomas homed in on the tors of Preseli as the likely sources of most of the bluestone monoliths at Stonehenge, it has been assumed that the monoliths were taken from the most prominent places in the landscape -- the high crags. Literally thousands of learned academic papers, book chapters, journal articles, popular magazine features, news reports, TV programmes etc have unknowingly and unthinkingly signed up to the same assumption. Did the spotted dolerite monoliths (and fragments in the debitage) come from Carn Meini or Carn Goedog, Cerrig Marchogion or Carn Alw, Carn Ddafad-las or Carn Gyfrwy? Acres of newsprint and millions of words devoted to the question "Here, or there?", "This tor or that tor?"
It's actually quite intriguing. I have got caught up in it myself, what with my blog posts extolling the virtues of the Preseli and Carningli tors and trying to encourage the general public to visit them and value them:
https://brian-mountainman.blogspot.com/2021/01/the-tors-of-carningli-and-mynydd-dinas.html
https://brian-mountainman.blogspot.com/2016/12/the-preseli-tors.html
Because they are so beautiful and impressive, it is easy to attach to the tors some sort of spiritual or sacred quality, and to say that "they have always been worshipped" or that they have always been deemed to be associated with the gods. In the Christian era some tors at least must have been invested with significance: Carningli summit was the place where St Brynach "communed with the angels", and the Bronze Age burial mounds on the summit of Foeldrygarn must indicate a reverence for the place............Then it's very easy to slip into the habit of linking these high rocky places with power or territorial control. The hillforts on Foel Drygarn, Carn Alw, Carningli and Carnffoi must have been built not just because these were good defensive sites but because they were statements of power: this is my territory -- keep away, or stray into it at your peril.......It's not much of a leap from there to assume (as the archaeologists have done) that since Stonehenge was as much a political statement as anything else, its component stones must have been sacred or powerful in themselves, so they must have come from sacred places, so they must have come from "the high places" that dominated the Preseli skyline, so they must have been quarried. We are of course now into circular reasoning, but that hasn't bothered anybody very much.
But hang on. Is there actually any evidence in West Wales that these "high rocky places" were valued by our prehistoric ancestors, and that the stones that came from the tors were especially sacred or special? Interestingly enough, there isn't. Let's look at the big and famous megalithic structures of West Wales. Pentre Ifan cromlech was not made from stones imported from a tor or high point in the landscape; the stones used were taken from a litter of largely local erratics. At Bedd yr Afanc the stones used are of several types, picked up locally and apparently used randomly. Carreg Samson has nothing to do with a prominent rock outcrop, and neither does Gors Fawr, and neither does King's Quoit, Coetan Arthur, Carreg Coetan Arthur, Bedd Arthur, or any of the other stone settings of West Wales. As pointed out by Nora Figgis, Steve Burrow, Stephen Briggs, Olwen Williams-Thorpe, Nikki Cook and many others, the Neolithic and Bronze Age monuments are all built of boulders, pillars and slabs of rock found locally and used more or less where found. The three Bronze Age burial mounds on Foel Drygarn are made of local bedrock slabs, not because they were sacred but because they were easily collected from adjacent outcrops.
Now let's think about geology. In his original work on the provenancing of the bluestones, HH Thomas was completely dependent for his analysis on samples taken from the crags. He did not do his own sample collecting, but depended upon samples collected by his BGS colleagues around 20 years previously. For practical reasons these came from prominent rock outcrops and not from the intervening saddles, cols and lower parts of the landscape. That, of course, introduced sampling bias. This bias has run through into the abundant studies by Rob Ixer, Richard Bevins and others within the last 15 years. They have studied hundreds of thin sections and collected samples from the high crags, always on the assumption that these are the "candidate" locations from which the bluestone monoliths must have come. They have found no perfect matches with Stonehenge samples, and although their provenancing work must by now have become reasonably accurate, they have had to admit, over and again, that some of their samples just do not quite fit their preferred source locations. As I have suggested many times on this blog, some of the foliated rhyolite material at Stonehenge might have come from Pont Saeson - Rhosyfelin, from one or more outcrops currently unsampled. Some of the spotted dolerite boulders and debris at Stonehenge might have come from the Carn Goedog sill, which covers c 60,000 sq m, but not necessarily from the tor itself.
Carn Goedog, Carn Alw and Carn Breseb -- lots of samples from the tors, but how many from the intervening landscape?
In their most recent "provenancing paper", Bevins et al (2022) demonstrate all too clearly how biased all of their work has been, regarding the attention paid to the "high crags". In seeking to discover where the unspotted dolerite boulders and fragments at Waun Mawn might have come from, it is clear that their underlying assumption is that the stones must have been fetched from somewhere else. That's dodgy enough as it is, but then the additional assumption is that they must have been fetched from somewhere prominent. All of their "candidate sites" subjected to detailed analysis are high crags or tors -- for example Cerrigmarchogion, Carn Ddu Fach, Carngoedog, and Carn Fach. They do not provide matches for Waun Mawn, and so further analyses are undertaken on samples from Cerrig Lladron and Carnau Ysfa -- small crags or tors closer to Waun Mawn. Cerrig Lladron is found to give the best petrological / geochemical match, and so that is proposed as a probable source for the Waun Mawn monoliths. They claim that these are the closest rock dolerite outcrops to Waun Mawn, but that is incorrect. There are other outcrops of dolerite on Waun Mawn moor itself, adjacent to the site of the supposed "lost giant circle". The fact that these outcrops were completely ignored in such a detailed study is extraordinary.
Bevins, R.E., Pearce, N.J.G., Parker Pearson, M., Ixer, R.A. 2022. Identification of the source of dolerites used at the Waun Mawn stone circle in the Mynydd Preseli, west Wales and implications for the proposed link with Stonehenge. Journal of Archaeological Science: Reports 45 (2022) 103556.
https://www.researchgate.net/publication/ 362119860_Identification_of_the_source_of_dolerites_used_at_the_Waun_Mawn_stone_circle_in_ the_Mynydd_Preseli_west_Wales_and_implications_for_the_proposed_link_with_Stonehenge
So this question arises: might the bulk of the Stonehenge bluestones have come from unsampled parts of the known and mapped Preseli intrusions and volcanic rock outcrops?
In answer to that question, we can point out that it is no longer tenable to refer to a small number of preferred bluestone locations in which quarrying activity was concentrated. The geologists themselves have had to admit that the sheer abundance of rock types in the Stonehenge bluestone assemblage points to multiple provenances, and that in itself points to glacial, rather than human, bluestone transport.
This brings us to glacial theory. From what we know about glacial entrainment and the transport of "quarried" or plucked blocks under or within an overriding glacier, is it possible that the Stonehenge bluestones have come exclusively from the high crags? From a number of recently published papers, this scenario looks increasingly unlikely. Back in 1965 my old friend Prof David Sugden argued, in his doctorate thesis, that some of the tors in the Cairngorms appear to have been protected, rather than eroded, by overlying ice. A number of subsequent articles, involving many different researchers, have pointed to the survival of tors on high mountain plateaux in other glaciated regions because the thin ice that covered them was cold based and largely immobile. In contrast, erosion was concentrated on the lower slopes and in the troughs where the ice was thicker, warm-based and fast flowing. This means that it was more "aggressive" in landscape transformation.
This suggestion appears to be supported by some of the new work on the cosmogenic exposure ages of rock surfaces in glaciated areas. To generalise, samples taken on the surfaces of erratic boulders appear, more often than not, to make sense; but samples taken on summit bedrock slabs are throwing up so many anomalies that it must be inferred that the recorded ages are false because of "age inheritance" over maybe hundreds of thousands of years. This in turn points to very limited or minimal glacial erosion or actual protection on these high rock surfaces. I will shortly be doing another post on this. See my comments on Carningli and Lundy Island:
But for now, here is a thought. I THINK THAT ALL OF THE GEOLOGICAL PROVENANCING WORK DONE OVER THE PAST 15 YEARS BY BEVINS, IXER AND THEIR COLLEAGUES MIGHT WELL BE COMPROMISED OR DEVALUED SIMPLY BECAUSE THEY HAVE TAKEN ALL OF THEIR SAMPLES FROM THE WRONG PLACES.
I'm not joking. I say this in all seriousess. Watch this space.
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