Author: Ben

Postdoctoral Research Associate for the Avebury Papers project. I’m responsible for conducting and commissioning analysis of the archaeological artefacts collected during excavations at Avebury in the 1930s.

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The curious case of Mrs St. George Gray and the West Kennet Avenue Axe (Part 1)

The inspiration for writing this blog came from finding an axe whilst trawling through the archive of weird and wonderful objects held in the Alexander Keiller Museum at Avebury.

Most of the objects in the museum were found during archaeological excavations and are boxed along with crucial information on which excavation they were uncovered by, and the cutting (excavation trench) and context (e.g. stone-hole, ditch, pit etc.) in which they were found. A smaller number are what we often call ‘stray finds’. These are finds that were found by chance, for example in a molehill or on the surface of a ploughed field, and therefore have little contextual information to go with them.

The axe in question was one such find. It was stored by itself in a small cardboard box, and all the contextual information we know about it is written on the object itself. The writing on it simply says:

“FLINT CELT FOUND BY MRS. ST. G. GRAY IN THE KENNETT AVENUE AVEBURY 1911”.

The axe found by Mrs St. George Gray in the West Kennet Avenue

Part of my job on the Avebury Papers Project is to catalogue all of the finds from Avebury that are held by the Keiller Museum. As a result, finding the axe hidden away on a shelf raised a few crucial questions for me. Some were basic ones, such as: what is the object, how old is it, and exactly where was it found. The latter question is essential. To archaeologists context is everything. Individual objects can tell us lots about past societies, but they hold a lot more value when considered as assemblages of objects, particularly if we also know what type of context they came from. An axe found in a midden might mean something quite different to one formally deposited into a pit. Beyond these relatively prosaic questions, there are other interesting questions that we can pose of this particular object, namely, who was Mrs St. George Gray, and how did she come to find the axe. I am going to attempt to answer as many of these questions as I can in the course of this blog.

The easiest of these questions to answer relate to the type and broad age of the artefact. The object is a ground and partly polished flint axe dating to the Neolithic period. This means that the axe was first flaked into a rough shape, and then finished by a combination of grinding and polishing of its surfaces. Sometimes the grinding of an axe’s surface covers the whole of the axe, sometimes it is patchy, covering the ridges between flake scars that stick out the most. Almost always, the grinding and polishing covers the cutting edge where it is used to create a sharp and durable edge suitable for working wood. Along with first appearance of pottery, and the construction of monuments, axes of this type are one of the defining features of the Neolithic in Britain (c. 4000 to 2400BC). Actually, all of these things occur in different parts of Europe in the preceding Mesolithic period (albeit not commonly), but that is a subject for another blog!

Polished flint and stone axes are regular finds on Neolithic sites, occurring from the start of the Neolithic up until the earlier part of the Late Neolithic. They occur most frequently on Early Neolithic sites, such as the Windmill Hill causewayed enclosure located 2km to the northwest of Avebury. Much closer to Avebury, flint axes also occur, albeit in smaller numbers, amongst the predominantly Middle Neolithic (c. 3500-2900 BC) artefact scatter known as the West Kennet Avenue Occupation Site. The occupation site lies on the line of the West Kennet Avenue and was first excavated in 1934 by Keiller and his team (see this blog post for details). The 1934 excavations yielded roughly 15 axes and adzes, with Isobel Smith noting in the excavation’s publication that partly polished and unpolished axes and adzes were the characteristic form of the assemblage (as in the photograph below).

Three axes/adzes found by Keiller’s excavation of the West Kennet Avenue Occupation Site in 1934. From left to right: The butt end of a flaked axe with ground margins; the cutting edge of an adze; a small complete flaked and partly ground adze or chisel.

So, the axe found by Mrs St. George Gray could certainly fit within the assemblage from the West Kennet Avenue Occupation Site. This is significant given that all we know of its find spot is that it was “in the Kennett [sic] Avenue”. It may, therefore, seem likely that it came from the West Kennet Avenue Occupation Site, but given that the Avenue itself is just short of 2.5km long it is worth considering whether it came from somewhere else along its length.

We can safely assume that Mrs St. George Gray is the wife of Harold St. George Gray, who excavated Avebury from 1908-1922. Given that the axe was found in 1911, the axe was most probably found by Mrs St. George Gray whilst her husband was excavating. But that doesn’t make deducing a more exact location of the find any easier.

We know that during the Gray’s excavations at Avebury only 19 of the West Kennet Avenue stones remained visible. The antiquarian William Stukeley had recorded 72 stones in 1722, and the Grays were clearly aware of his description of the course of the West Kennet Avenue. In Mrs St. George Gray’s time, as today, the most visible part of the Avenue was its northernmost third where it reaches Avebury. In 1911, however, even in this stretch, many of the stones were buried, awaiting their re-erection by Keiller’s team in 1934 and 1935.

What we also know, thanks to the recent excavations of Josh Pollard and Mark Gillings, is that this stretch of the West Kennet Avenue was rarely ploughed, with the artefact scatter that makes up the West Kennet Avenue Occupation site lying a good depth under the topsoil. This means that it is unlikely that Mrs Gray would have come across the axe kicking around on the surface, unless it had been fortuitously brought up in a molehill, something that does happen on occasion.

Another possibility is that she found it whilst tracing the route of the Avenue in the field immediately south of the currently reconstructed part of the Avenue, a field which we know has been regularly ploughed in the past. It is also possible that the axe was found further from Avebury as the Avenue winds its way towards the Sanctuary, but this is perhaps less likely given how interrupted the remaining stones of the Avenue are in this part of its route, and therefore how less certain it would be that it was found “in” the Avenue.

Hopefully it is not too anti-climactic, but that is all we can deduce about the find spot of the axe. It is a significant find, but it would be a lot more so if we could be certain about exactly where it was found, and particularly whether it was part of the West Kennet Avenue Occupation Site, or potentially some other concentration of features or artefacts along the route of the Avenue.

We are left with two possibilities. Either it was found, most likely in a molehill, in the extant northern third of the Avenue, or it was found further to the south, probably in a ploughed field in a location where it was still possible to confidently establish where the line of the Avenue was. Either is possible, although I am somewhat in favour of the idea that the axe was part of the West Kennet Avenue Occupation, found by Mrs Gray some 23 years before Keiller’s discovery of the site. Unfortunately we will never know the truth. If nothing else, the story highlights the importance of accurately recording the find spots of stray finds!

Having dealt with the archaeological significance of the find, we can now turn to the finder herself. Up until now she has only be referred to as ‘Mrs St. George Gray’. This has not been to diminish her individuality or personhood, rather it is a simple reflection of the fact that when I started writing this blog that was all that I knew of her. Indeed, that was all that any of the current crop of Avebury archaeologists knew of her. In the literature, she is very much in her husband’s shadow. Even in her husband’s obituary published in the Somerset Archaeological and Natural History Society in 1963 she is only referred to as Mrs Gray. Uncovering the hidden histories of people involved in the Avebury excavations is very much at the heart of the Avebury Papers Project, and so along with investigating the possible find spot of the axe, its discovery in the archive prompted me to find out all that I could of Mrs St. George Gray. For now, though, this blog is getting rather long, so the identity of Mrs St. George Gray will have to wait for the next post…

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Surveying Avebury’s Stones (with poles!)

The West Kennet Avenue in bloom.
The West Kennet Avenue in bloom.

Visitors to Avebury recently may have witnessed the odd sight of two people walking around with cameras on the end of long poles. Certainly, many people came up to ask what we were doing, and no, it wasn’t part of a mysterious mid-summer ritual!

The truth is sadly more mundane. Adam Stanford of SUMO GeoSurveys (https://www.sumoservices.com/archaeology-geophysical) and I have been conducting a survey of the Avebury and West Kennet Avenue stones using a technique known as photogrammetry, a technique for generating 3d models of objects.

I should add that our survey happened to coincide with a period of beautiful sunny weather. The brilliant sunshine and strong shadow was far from ideal conditions for stone photography, but it was hard to worry about that as the buttercups were out and the West Kennet Avenue was looking rather magical!

Adam Stanford using a camera on a pole to photograph the top of a stone on the West Kennet Avenue.

In order to make the photogrammetric model, we take overlapping photos of the stones from every possible angle (hence the long poles). This involved taking roughly 150 shots for each stone. Once the photographs have been taken, we use software to generate a 3d point cloud by triangulating the positions of individual points on a stone using multiple photographs taken from different angles.

The end result is an accurate 3d model of each stone.

Screen capture of the construction of the 3d model. The blue rectangles show the location and direction of each photograph the model is being compiled from.

Those of you that follow the Avebury Papers project will know that the focus of our project is on digitising the archive from Avebury’s 20th century excavations. Therefore, you are probably wondering why we want to survey the stones. The answer is a little convoluted.

The starting point is that there are lots of photographs of Avebury’s stones in the Keiller archive (we estimate there to be 2000 of them!). Many of these are only partial images of stones taken from odd angles as they were being uncovered, or re-erected, in the 1930s. It is quite difficult to identify which stones appear in the photographs but this is information that we would very much like to add to our catalogue so that ultimately people will be able to search for all the images and written records associated with each individual stone on the site.

Whilst trying to work out how we were going to identify these stones, the opportunity came up to work with some clever people at the University of York involved with machine learning. They have set up a project that aims to teach a computer to identify the stones in the photographs for us. I won’t go into more detail here as this part of the project will be covered in detail in a future blog post. Suffice to say, the first step is to give the computer some images of Avebury’s stones to use as a reference point. These photos need to provide the computer data on what every stone looks like from every possible angle, and so the obvious starting point was to create a 3d model of the stones using photogrammetry. A few examples of what the models look like can be seen below.

3d model of Avebury Stone 9.

AS-09 by SUMO GeoSurveys on Sketchfab

3d model of West Kennet Avenue Stone 35A.

WKAS-35A by SUMO GeoSurveys on Sketchfab

Beyond teaching a computer to recognise a stone, there are many more reasons why the photogrammetric survey is a great idea.

First of all it will provide accurate 3d survey data that will be essential baseline data for the future management of the monument.

Secondly, the survey opens up lots of avenues for further research. For example, it will allow us to conduct a detailed quantified analysis of the surfaces of the stones. Many of the stones at Avebury have evidence of differing amounts of flaking and pecking of their surfaces. This is of interest as, unlike Stonehenge, Avebury’s stones are often thought of as being natural sarsen boulders that have not been dressed. We will use the photogrammetric model to try and work out how much of the surface alteration of the stones relates to the working of them in prehistory, as opposed to natural weathering, or medieval and later attempts to break or bury the stones.

Ultimately, we aim to survey the whole of the monument, including its banks and ditches. Once this has been done the model will also be able to quantify the volume of its earthworks to a higher level of accuracy than has previously been possible.

Alongside an improved understanding of the pecking and flaking of Avebury’s stones, this information will be an essential component in understanding the scale and complexity of the Neolithic construction of the monument.

For now, though, there is more survey work to be done. We estimate that we may need to take 15,000 photographs before we have captured every stone from every possible angle. So you may well see more people wandering around with cameras on poles in the months to come!

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On Keiller’s excavation of the West Kennet Avenue and why we wash flint…

Whilst going through the archive in the Alexander Keiller Museum I came across some boxes of worked flint from the West Kennet Avenue. The material consists primarily of flint flakes, some of which is waste material from making stone tools, some of which are tools in their own right. The latter would have been flakes used for cutting and scraping a variety of materials such as wood and animal hides. The material in the finds archive in the Museum is conspicuously clean and carefully boxed and packaged, but for some reason this material was only poorly washed with mud still adhering to many of the artefacts. The objects needed a wash and the following is a long winded explanation of why!

One evening in 1934…

Two men met in the Red Lion in Avebury. The two men were Alexander Keiller and Stuart Piggott. Their first encounter was in 1928 when Piggott, then only 18 years old, was already a keen archaeologist with an interest in Neolithic pottery. By 1933 Piggott had taken up an appointment to help Keiller study the Windmill Hill pottery. He had also suggested to Keiller that small-scale excavation could reveal the course of the West Kennet Avenue, which at that stage had only a few standing stones remaining. The majority had been either fallen, been buried, or were broken up for building stone centuries before. Keiller thought that Piggott’s idea was excellent, and in typical Keiller fashion, took it and expanded it exponentially.

When Keiller and Piggott met in the Red Lion that evening in 1934, Keiller told Piggott that he had decided to buy the whole of the Avebury monument and as much of the West Kennet Avenue as he could, all with the aim of excavating and restoring the monument to its former glory.

The West Kennet Avenue prior to excavation in 1934,
Photo Album B, 78510301_104_a.

It was a grand vision of a type that few could have resourced or even begun to imagine. The work began with the excavation of the West Kennet Avenue in 1934. The primary aim was to track the course of the Avenue by uncovering stone-holes and buried stones. The most efficient means to do so was through the excavation of two long parallel trenches on the alignment of the two rows of stones that made up the Avenue. Quite unexpectedly, during the course of the excavation a large artefact scatter was uncovered in the middle of the Avenue. The scatter is located towards the southern end of the section of the Avenue that Keiller subsequently restored. Thousands of visitors still walk across it every year without ever knowing that it is there.

The West Kennet Avenue during the excavation, Photo Album A, 78510300_006_d.

Keiller was interested in the scatter, which he deemed to be the remains of a prehistoric settlement, and extended the area of excavation to further investigate it. Ultimately the excavation retrieved over 1000 flint tools, associated waste flakes, and 600 sherds of pottery known as Peterborough Ware. The pottery indicated that the site was a Neolithic settlement site (later work showing that it dates to around 3000BC), and the scatter was named the West Kennet Avenue Occupation Site.

The West Kennet Avenue excavation in 2015.

The artefacts were later studied by Isobel Smith, who published them in 1965 along with the results of the rest of Keiller’s Avebury excavations. Archaeologists have known about the site, and particularly the excellent state of preservation of its artefacts, ever since but very little else was done with the material or the site until 2013 when Mark Gillings and Josh Pollard reinvestigated it over three seasons of excavations.

Mark and Josh’s team retrieved many more artefacts (over 16,000!), and also revealed two reasons that the artefacts are so well-preserved. The first is that, presumably due to the presence of the Avenue and its buried sarsens, there has been no significant ploughing of the area. This is good for archaeologists as it means that the artefacts have not been moved around in the soil, not only preserving their spatial distribution, but also the objects themselves, which can become abraded and worn by the action of the plough. The second was that the soil in the area of the Avenue had become decalcified, with the calcium carbonate that is ever present in chalky soils having been leached out of it.

This is great for those of us that study chalkland flint assemblages, as flint from chalky soils are normally heavily patinated. That means that there normally black or dark grey lustrous surfaces have become white and dull. But, this makes it hard to study the edges of stone tools, where we are often looking for fine traces of use. This is important because when flint tools are used to conduct tasks such as scraping hides, grooving bone, or processing plant fibres, their edges become worn.

At a microscopic level that wear will vary in character according to the types of materials that a tool has been used on. The technique for studying these traces of wear is rather unimaginatively called use-wear analysis, and it is very useful at revealing the range of craft and subsistence activities that took place on a site.

A photo of a serrated flake from the West Kennet Avenue
The microscopic wear present on the teeth of a serrated flake

I have previously analysed Mark and Josh’s assemblage from the West Kennet Avenue Occupation Site and sure enough the tools in the assemblage did preserve use-wear traces. These tell us that varied activities took place on the site, including hide working and the processing of the fibres of plants such as nettles.

When Keiller was excavating the Avenue, use-wear didn’t even exist as a discipline, so they had no idea what the analysis of the flint from the site could add to their understanding. This may explain why they didn’t feel the need to wash the flint from the excavation!

Me talking to the APEX Team (its not just an empty room, honest!)
The washed flint being dried out and ready for rebagging

Well, we need clean flint for use-wear analysis, and rest assured, thanks to the efforts of Briony Clifton of the National Trust and her team of volunteers (the brilliantly-named APEX team!), the flint is now all shiny and new-looking. Now I just need to analyse it all.

Once this has been done we will hopefully know much more about the types of activities that took place on the site, and whether they differ between the areas excavated by Keiller, and the more recent trenches.

This will aid our interpretations of the settlement. Was it permanently or seasonally occupied? Was it a short-lived occupation, or something more long term? Was it a settlement at all, or just a working area? These are all questions that we hope to be able to answer once the analysis has been completed.