Beginning of the Circle?

The research article Greaney, S. et al. (2025) ‘Beginning of the circle? Revised chronologies for Flagstones and Alington Avenue, Dorchester, Dorset’, Antiquity, pp. 1–17. doi:10.15184/aqy.2025.28. published in Antiquity in 2025, presents significant new findings on the dating of proto-henges, particularly focusing on the Flagstones enclosure in Dorset, UK. Using an extensive radiocarbon dating program and Bayesian chronological modeling, the study provides a refined timeline for the construction and use of Flagstones and compares it to other key monuments like Stonehenge and Llandygai 'Henge' A. 

Flagstones Enclosure

• Construction Date: The Flagstones enclosure, a 100m-diameter circular monument made of intercutting pits, was constructed between 3315–3130 cal BC (95% probability), with a probable range of 3285–3215 cal BC (41%) or 3210–3160 cal BC (27%). This makes it one of the earliest precisely dated large circular enclosures in Britain.
• Funerary Activity: Burial activity, including inhumations and cremations, began shortly after construction, estimated at 3265–3105 cal BC (95% probability), probably 3230–3220 cal BC (4%) or 3205–3120 cal BC (64%), and ended between 3220–3065 cal BC (95% probability), probably 3150–3090 cal BC (68%). This activity spanned a relatively short period of 1–170 years (95% probability), suggesting it may have been part of the site’s initial dedication.
• Context: Flagstones predates the nearby Mount Pleasant henge (built 2615–2495 cal BC) by several centuries and is closer in time to Early Neolithic monuments like the Maiden Castle causewayed enclosure (3660–3635 cal BC or 3570–3525 cal BC) and the Alington Avenue long enclosure (before 3625–3380 cal BC).

Alington Avenue

• Construction Date: New radiocarbon dates from a cattle skull in the northern ditch of the Alington Avenue long enclosure indicate it was built before 3625–3380 cal BC (95% probability), probably before 3605–3405 cal BC (68%). This places it 110–470 years (95% probability) earlier than Flagstones, marking it as an earlier linear monument in the Dorchester complex.

Comparison with Other Proto-Henges

• Stonehenge: The first phase of Stonehenge, a segmented circular ditch, is dated to 2980–2720 cal BC (95% probability), probably 2940–2800 cal BC (68%), making Flagstones 70–285 years earlier (95% probability). Cremation burials at Stonehenge began in 3075–2945 cal BC and ended in 2890–2765 cal BC, later than those at Flagstones.
• Llandygai 'Henge' A: Funerary activity at this 80m-diameter enclosure started in 3655–3345 cal BC and ended in 3075–2715 cal BC, earlier than Flagstones’ construction, though the enclosure itself lacks direct dating. This suggests a longer tradition of circular monument use in some regions.
• Stones of Stenness (Orkney): Previously considered one of the earliest henges, its ditch dates to 3035–2895 cal BC, later than Flagstones, reinforcing Flagstones’ claim as an early example.

Broader Implications

• Earliest Circular Enclosure?: Flagstones may be the earliest large circular enclosure in Britain with precise dating, predating Stonehenge and other candidates like the Stones of Stenness. Other potential early sites (e.g., Ysceifiog, Priddy Circles) lack sufficient excavation or dating to challenge this.
• Transition to Circular Forms: The study highlights Flagstones as a key marker in the shift from linear (e.g., long barrows, cursus monuments) to circular monument archetypes in the Middle Neolithic (3400–2800 cal BC), bridging earlier causewayed enclosures and later henges.
• Funerary Practices: The mix of inhumations and cremations at Flagstones reflects an early phase in the transition to cremation rites, paralleled at Stonehenge and Llandygai, and tied to smaller ringform enclosures (dated 3960–3400 cal BC to 3265–2605 cal BC).

Significance

This research refines the chronology of proto-henges, positioning Flagstones as a pioneering circular monument that influenced later developments, such as Stonehenge. It underscores continuities with Early Neolithic practices (e.g., pit construction) while introducing innovations like large circular forms and cremation burials, possibly inspired by connections with eastern Ireland. The precise dating enhances our understanding of the Middle Neolithic’s monumental landscape and its cultural transitions in Britain.

Peer reviewing John 2025

(I am happy to share without comment an independent peer review of John 2025 - it is not by me or anyone involved in the debate.)

An expanded review of "Response: The Provenance of the Limeslade Igneous Erratic: A Matter of No Importance?" by Brian John, (Quaternary Newsletter Vol. 164, February 2025), and the previous "interim report" John, B.S. (2024). An Igneous Erratic at Limeslade, Gower & the Glaciation of the Bristol Channel. Quaternary Newsletter 162, 4 - 14

### Overview 

1. **Interim Report**:

   - Describes a large dolerite erratic at Limeslade Bay, Gower Peninsula, suggesting transport by the Irish Sea glacier. It posits implications for Stonehenge bluestone transport, favoring glacial over human mechanisms.

   - Key points include the erratic’s size (over 2m, ~5 tons), its non-local dolerite composition, and its position in the intertidal zone, with ongoing provenancing work noted.

2. **Response Article (Quaternary Newsletter Vol. 164)**:

   - A rebuttal to Pearce et al.’s (2024) critique in QN 163 of John’s earlier note (QN 162). It defends the interim findings, addresses criticisms of methodology and interpretation, and expands on the erratic’s significance for Bristol Channel glaciation and Stonehenge debates.

   - Emphasizes the erratic’s size and context (e.g., associated smaller erratics), refuting claims of its insignificance and challenging ice-rafting hypotheses.

Both of John's documents argue for glacial transport, but the response escalates the debate, engaging directly with critics and reinforcing the erratic’s relevance.

---

### Failures of Logic

#### 1. Interim Report

- **Assumption of Irish Sea Glacier Transport**:

  - Logic: The report assumes the erratic was transported by the Irish Sea glacier without fully exploring alternatives (e.g., Welsh ice or fluvial processes). This is a potential oversight, as the Gower Peninsula’s proximity to Welsh ice sources isn’t adequately discounted.

  - Issue: While supported by the erratic’s non-local dolerite nature, the lack of discussion on competing ice flows weakens the argument.

- **Stonehenge Bluestone Link**:

  - Logic: The connection to Stonehenge bluestones relies on the erratic’s glacial transport as a parallel, but the distances (50-60 km vs. 150-200 km) and timing (Anglian glaciation vs. Neolithic construction) aren’t reconciled.

  - Issue: This leap assumes bluestones were glacial deposits later moved by humans, but the report doesn’t clarify this intermediate step, risking overgeneralization.

- **Limited Data Acknowledgment**:

  - Logic: The report admits the pXRF data’s limitations (three readings) but proceeds to draw implications, potentially overstating preliminary findings.

  - Issue: This tension undermines confidence in conclusions without stronger caveats.

#### 2. Response Article (Quaternary Newsletter Vol. 164)

- **Terminology Debate (Irish Sea Glacier vs. Ice Stream)**:

  - Logic: John dismisses Pearce et al.’s critique of “Irish Sea Glacier” vs. “Irish Sea Ice Stream” as pedantic, citing interchangeable usage in literature (e.g., John, 1968a, 2018). However, he doesn’t justify why this distinction lacks substantive impact on his argument.

  - Issue: If ice stream dynamics (e.g., faster flow, specific paths) differ from a broader glacier, this could affect transport feasibility, and John’s casual dismissal avoids engaging with potential implications.

- **Rejection of Ice Rafting**:

  - Logic: John argues against Pearce et al.’s ice-rafting hypothesis (Scourse, 2024), asserting that coastal erratics result from in situ glacial deposits eroded by waves, not floating ice. He cites examples like Whitesands and Rödloga Storskär but generalizes without addressing site-specific evidence for Limeslade.

  - Issue: This risks a hasty generalization. Ice rafting could explain some erratics and dismissing it outright without Limeslade-specific counterevidence weakens the rebuttal.

- **Stonehenge Transport Polemic**:

  - Logic: John denies a polemic against human transport advocates (e.g., Parker Pearson et al., 2021), claiming a neutral review, yet his tone and selective focus on their “retreats” (e.g., Waun Mawn) suggest bias.

  - Issue: This contradiction undermines his claim of objectivity, as the response prioritizes refuting human transport over balanced discussion.

- **Extrapolation to Somerset**:

  - Logic: John posits an ice margin 50 km inland from Somerset based on erratics up to 80m asl and modeling (e.g., Boulton & Hagdom, 2006), challenging Pearce et al.’s reluctance to accept widespread glaciation. However, he doesn’t reconcile this with patchy till evidence or alternative explanations (e.g., periglacial processes).

  - Issue: Overreliance on modeling and selective high-altitude erratics risks overstating glacial extent without addressing gaps in field evidence.

---

### Missing References

#### 1. Interim Report

- **Rock Provenancing**:

  - Missing: Detailed citations for dolerite identification beyond preliminary pXRF (Parry & Darvill). Geological surveys or petrological studies (e.g., akin to Bevins et al., 2014) are needed for North Pembrokeshire linkage.

  - Impact: Ongoing work is noted, but the lack of interim references limits credibility.

- **Glacial History**:

  - Missing: Citations for Irish Sea glacier extent and flow (e.g., Scourse et al., 2019, 2021, though later referenced in the response). Regional glacial studies are assumed but not specified.

  - Impact: This leaves the transport mechanism’s foundation vague.

- **Stonehenge Context**:

  - Missing: References to bluestone composition or glacial evidence near Stonehenge (e.g., Kellaway, 1971, though debated). Comparative erratic studies are absent.

  - Impact: The analogy to Stonehenge lacks grounding without these.

#### 2. Response Article

- **pXRF Critique Defense**:

  - Missing: Specific studies validating pXRF as a preliminary tool (e.g., Potts et al., 2006, is cited but not tied directly to methodology defense). John counters Pearce et al.’s hostility but lacks methodological benchmarks.

  - Impact: This weakens his rebuttal of their geochemical critique.

- **Carn Meini Variations**:

  - Missing: Additional references beyond Bevins et al. (2014) and Kokelaar et al. (1984) to support John’s claim of lateral variations in Preseli tors, contra Pearce et al.’s consistency argument.

  - Impact: The disagreement rests on interpretation without exhaustive citations, limiting persuasiveness.

- **Ice Rafting Counterevidence**:

  - Missing: Direct studies on Limeslade’s depositional context to refute Scourse (2024). General examples (e.g., St. Lawrence River, Guillaume, 2022) are cited, but site-specific data is absent.

  - Impact: The rejection of ice rafting lacks localized support, relying on broader analogies.

- **Somerset Glacial Extent**:

  - Missing: Field studies beyond Hunt (2006) and Kellaway (1971, 2002) to confirm inland ice margins. Modeling citations (e.g., Hubbard et al., 2009) are broad but not tied to specific Somerset evidence.

  - Impact: The extrapolation to Stonehenge’s vicinity needs more robust regional data.

---

### Comparative Analysis and Broader Implications

- **Logical Consistency Across Documents**:

  - The interim report cautiously suggests glacial transport, while the response doubles down, aggressively defending against Pearce et al.’s critique. This shift from tentative to assertive may reflect reaction to criticism rather than new evidence, risking logical overreach (e.g., Somerset ice margin).

- **Reference Gaps**:

  - The interim report’s brevity excuses some omissions, but the response, despite a long reference list, selectively engages with critics’ work (e.g., citing Bevins et al., 2022, but not fully countering their data). This mirrors John’s accusation of Pearce et al. ignoring “inconvenient literature,” suggesting mutual gaps.

- **Debate Context**:

  - The documents fuel a polarized debate—glacial (John) vs. human transport (Pearce et al., Parker Pearson et al.). The Limeslade erratic’s size and location bolster John’s case, but logical leaps and missing field data hinder definitive resolution.

---

### Conclusion

The interim report presents a plausible glacial transport hypothesis for the Limeslade erratic but falters in assuming a single mechanism and linking to Stonehenge without robust data. The response strengthens this stance but introduces new logical flaws (e.g., dismissing ice rafting broadly, overstating Somerset glaciation) and fails to fill reference gaps with site-specific evidence. Both documents reflect an ongoing, contentious scientific exchange, where logical rigor and comprehensive citation are sacrificed to interim constraints and rebuttal fervor. Future work, as John notes, requires detailed provenancing and field studies to resolve these issues.

The Limeslade Erratic again

A strange little article has appeared in the  Quaternary Newsletter 164, pp 19 - 27 (February 2025) about the Ice Rafted Erratic spotted at Limeslade in South Wales. 

https://www.qra.org.uk/mp-files/qn-164_6_limeslade-erratics-response.pdf/

A quick perusal reveals that the scientific argument rests on these two statements:

"In spite of the fact that far-travelled glacial erratics occur well above the coastal platforms on the south shore of the Bristol Channel, and up to an altitude of at least 80 m," (No reference given).

"more to the point they need to explain why ice from the Irish Sea Ice Stream can have left its traces at Kenn, Yew Tree Farm, Court Hill, Portishead Down and other localities up to c 80 m as without first filling the substantial lowland of the Somerset Levels"

(Gilbertson D.S. and Hawkins A.B. (1978). The Pleistocene Succession at Kenn, Somerset. Bulletin of the Geological Survey of Great Britain, 66, 41 pp).   

Unfortunately the G&H reference is outdated and there is no evidence for any glacial erratics naturally occurring much above sea level south of the Bristol Channel - see 
The Myth of Bristol Channel High-level Glacial Erratics   for details and references.

Without this myth the response is just a polemic that insults the intelligence of the readers of the QN.

As Willy wrote in Hal V, quoting Plato;"I did never know so full a voice issue from so empty a heart. But the saying is true: “The empty vessel makes the greatest sound.”

An imaginary scene but closer to the truth than the alternative theory

More Rock Carvings At Stonehenge Revealed

A new preprint paper discusses novel techniques 

for enhancing the visualization and recognition of rock carvings at Stonehenge.

​

The study introduces two new methods, difference of Gaussians (DoG) and pseudo-depth mapping (PDM), and compares them with existing techniques like radiance scaling and openness.

​

Additionally, a machine learning classifier, MeshNet, is adapted for carving recognition.

​

The DoG method identified two new carvings and several potential areas of carvings, while PDM revealed two additional carvings.

​

MeshNet achieved a 91.0% accuracy in distinguishing carved from non-carved surfaces.

​ The study concludes that these methods can significantly improve the identification of highly faded carvings and suggests further research into automated carving recognition.

The paper is freely available:

Leong, Gavin and Brolly, Matthew and Anderson-Whymark, Hugo and Nash, David and Bedford, Jon, Novel Approaches for Enhanced Visualisation and Recognition of Rock Carvings at Stonehenge. Available at SSRN: https://ssrn.com/abstract=5126093 or http://dx.doi.org/10.2139/ssrn.5126093

I would be interested if they looked for Atkinson's dagger carvings on Stone 11 as well.

https://www.sarsen.org/2024/09/the-mystery-of-dagger-carvings-on-stone.html

The Archive Excavation of the Altar Stone - Updated

In 1958 Richard Atkinson excavated around the Altar Stone at Stonehenge. Photographs of the excavation held in the Historic England Archive were examined by Tim Daw on 28th January 2025 with the greatly appreciated assistance of Simon Banton. Many of the photos were not recorded as being of the Altar Stone and were found only by careful study of entire archive. The following illustrate previously unrecorded features of the Altar Stone. The photos are labelled with the Historic England archive number, and original archive description, and the direction of the shot is illustrated on the annotated plan below.

They have been digitised by Historic England for Tim Daw. They are all copyright Historic England and reproduced here under Permission No: 10238.  The version of this blog post using the reduced size digital copies is https://www.sarsen.org/2025/02/the-archive-excavation-of-altar-stone.html

This updated version uses the online digital copies on the Historic England archive website so they can be enlarged for study.  The digitised versions available from Historic England are better quality than the online versions but I can't reproduce them for copyright reasons. 

Other photos of the excavation of the Altar Stone are in the archive - A search for "Alter Stone" sic will also find more.

He also lifted Stone 55B to examine the underside of 55B – the very brief description of the excavation is in his book “Stonehenge, 1979 revised edition” and does not include a description of the lifting of 55b. The photos in the archive seem to be the only record revealing its finely worked surface. 

The photo locations based on Atkinson’s plan in Cleal et al, rotated for convenience.



P51196 (1958 Excavation Near Alter Stone (St.80))
The excavated North East face showing the break and loose fragments.

P51908 (1958 Excavation Of Altar Stone,Stone 80) Looking South West at excavated Altar Stone. P51909 is very similar but not digitised.

P50361 (Excavated Unidentified Stone) The South East end from the North East 

P50359 (Excavated Unidentified Stone) Vertical of South East end

P50102 (1958 Excavation Of Altar Stone. S.E. End, View S.W.) South East end from the South West showing the graffito noted as “IB” by Atkinson on his plan. Stone 55b is to the left.

Simon Banton notes that a similar engraving, “FB”, is on Stone 62. The crossed I or F is also similar to the symbol on the WREN graffito on Stone 52.

 

Photos from Stones of Stonehenge - Simon Banton

P50002 (Unidentified Stone, Carved Initials "Id”) South East end from South showing “IB” engraving

Online version - needs to be rotated;

P50005 (2 Unidentified Stones In Excavation) The South West side of the Altar Stone under 55b taken at night for lighting purposes. The stone extends from the break in the foreground to the baulk under 156. 

Online version - needs to be rotated;

P50009  (2 Unidentified Stones In Excavation) is a similar photo revealing the fine working of the stone. The scratches at the top of the stone are similar to the ones on the middle section, see below, but from these photos it is uncertain what they are.

P51808 (1958 Excavation Of Alter Stone, Stone 80) Altar Stone – The middle section of the top surface between 55b, top, and 156, bottom,



P50107 (Surface Of Altar Stone From North East) Middle Section of South West side of the Altar Stone showing engraved lines, taken from South West . 

P50106 is similar. These scratches have obvious similarity to other neolithic stone markings. The vertical line is thought to be a quartz vein in the stone.

 

P51811 (1958 Excavation Of Alter Stone, Stone 80) Altar Stone North West end from above, standing on 156.




P51805 (1958 Excavation Of Alter Stone,Stone 80) North West end of the Altar Stone under 156.

P51803 (1958 Excavation Of Alter Stone,Stone 80) North West end of the Altar Stone from the South West 

  

P51874 (1958 Lifting Of Stone 55B) – The best photos of the top of the Altar Stone, it doesn’t seem to have been photographed when 55b was lifted.

P51873 (1958 Lifting Of Stone 55B) looking South East with the Altar Stone exposed. The methods used for the lifting of the stone might be thought not to follow present day best practice.

The online version needs to be rotated.

P50371 (Atkinson Looking At Unidentified Stone With Cable) Richard Atkinson underneath 55b looking South West, he is lying against 156 and 55a is on the ground to the left protected by the wooden post.  

Unraveling Ancient Skins: Pigmentation Insights from Ancient DNA

This study delves into the fascinating world of ancient genetics, specifically focusing on the skin, hair, and eye colour of early Europeans determined through their DNA. The team, led by researchers like Silvia Perretti and Guido Barbujani, uses a statistical method known as genotype likelihood to analyze ancient DNA samples.

• The first light-skinned individuals appeared in the Mesolithic period (14,000-4,000 years ago).
• During the Bronze Age (7,000-3,000 years ago), the proportion of dark-skinned people was still significant.
• During the Iron Age (3,000-1,700 years ago), light skin color began to dominate.

The real turning point was the spread of Neolithic farmers, who arrived from Anatolia 10,000 years ago. These early farmers carried genes for lighter skin, which probably gave them an evolutionary advantage in the less sunny climate of Europe. Their genes spread over time, but the process was slow and uneven. 
Traditionally, lighter skin has been thought to have evolved to enhance vitamin D production, but new evidence suggests that diet may have played a key role. As humans evolved from small nomadic groups to larger, agricultural communities, their diets changed. They relied less on wild game, which was rich in vitamin D, and more on cultivated plants, which lacked the vitamin. This change, along with the need to absorb more sunlight in northern latitudes, may have led to the development of lighter skin."

https://www.origo.hu/tudomany/2025/02/bor-sotet-volt-europaban


The actual paper:

Abstract:

Light eyes, hair and skins probably evolved several times as Homo sapiens dispersed from Africa. In areas with lower UV radiation, light pigmentation alleles increased in frequency because of their adaptive advantage and of other contingent factors such as migration and drift. However, the tempo and mode of their spread is not known. Phenotypic inference from ancient DNA is complicated, both because these traits are polygenic, and because of low sequence depth. We evaluated the effects of the latter by randomly removing reads in two high-coverage ancient samples, the Paleolithic Ust’-Ishim from Russia and the Mesolithic SF12 from Sweden. We could thus compare three approaches to pigmentation inference, concluding that, for suboptimal levels of coverage (<8x),  a probabilistic method estimating genotype likelihoods leads to the most robust predictions. We then applied that protocol to 348 ancient genomes from Eurasia, describing how skin, eye and hair color evolved over the past 45,000 years. The shift towards lighter pigmentations turned out to be all but linear in time and place, and slower than expected, with half of the individuals showing dark or intermediate skin colors well into the Copper and Iron ages. We also observed a peak of light eye pigmentation in Mesolithic times, and an accelerated change during the spread of Neolithic farmers over Western Eurasia, although localized processes of gene flow and admixture, or lack thereof, also played a significant role.

Inference of human pigmentation from ancient DNA by genotype likelihood Silvia Perretti, Maria Teresa Vizzari, Patrícia Santos, Enrico Tassani, Andrea Benazzo, Silvia Ghirotto, Guido Barbujani bioRxiv 2025.01.29.635495; doi: https://doi.org/10.1101/2025.01.29.635495 

This is a preprint and has not been certified by peer review

Water swollen wooden wedges for splitting stone, a myth?

We have all heard of splitting stones by inserting dry wooden wedges into cracks and then soaking them. But I can't find any examples of it actually being tried. Literature searches give me these results:

"The use of wooden wedges and hydraulic expansion to split stone occupies a nebulous position between historical anecdote and mechanical plausibility. While physics principles and traditional narratives support its feasibility, the absence of contemporary demonstrations or archaeological incontrovertible evidence leaves the method in the realm of theoretical speculation."

"No experimental or quantitative data exists for the specific use of water-swollen wooden wedges in splitting stone.
The hypothesis that water-swollen wooden wedges were used as a stone-splitting technique is archaeologically plausible but lacks modern experimental support."

"while the theoretical framework and related experimental studies provide a basis for understanding the mechanics of wetting and splitting, the absence of specific practical demonstrations leaves a gap in empirical validation of this method."

So is it a myth or was it actually used? 

Roger Rowell claims to have seen the technique used in Egyptian quarries:

On a trip to Egypt in 2001, the author saw the evidence first hand. On the edge of a shear granite cliff, holes about 15 cm long, 5 cm wide and 10 cm deep had been chiseled into the rock. Dry wooden wedges the size of the cavities were driven into these holes. Water was then poured onto the dry wood and allowed to swell. The swelling pressure caused the granite to split down the chain of holes resulting in a giant obelisk or other large building blocks. 

Rowell, Roger. (2012). 4 Moisture Properties. Handbook of Wood Chemistry and Wood Composites. 10.1201/b12487-7. 

Further citations are provided in: Nishiyama, Yoshiharu. (2023). Thermodynamics of the swelling work of wood and non-ionic polysaccharides: A revisit. Carbohydrate Polymers. 320. 121227. 10.1016/j.carbpol.2023.121227. 

A quite demonstrative example is the splitting of granite rocks by the swelling power of wooden wedges inserted in small chiseled holes as was witnessed by Rowell (2012) for which many authors assert the use of such methods in ancient Egypt (Eder, Schäffner, Burgert, & Fratzl, 2020;Katz, 1917), though the historical veracity seems controversial (Harrell & Storemyr, 2009).

Harrell & Storemyr, 2009 are quite clear:

A fiction often repeated in the popular archeological literature is that the wedge holes were cut for wooden wedges which, when wetted, would expand and so split the rock. In reality, this cannot work for the sizes, shapes, spacings, and often inclined orientations of wedge holes found in ancient hardstone quarries. Wooden wedges have been successfully employed in some modern hardstone quarries, but these require different kinds of wedge holes. (Harrell & Storemyr, 2009)

El-Sehily, B.M.. (2016). Fracture Mechanics in Ancient Egypt. Procedia Structural Integrity. 2. 2921-2928. 10.1016/j.prostr.2016.06.365.  provides details of a trial using swollen wooden wedges, to crack the rock blows were then applied to the stressed rock.