School of Human & Environmental Sciences
Experimental archaeology Developing experimental approaches in archaeology at Reading
What is experimental archaeology? All archaeologists study the fragmentary records of past human activities, which have been formed and modified over long timescales. Yet the traces we find often relate to activities and skills with which we are not familiar. These traces therefore need to be interpreted in terms of past ways of life and presented to the wider public in an accessible, questioning and engaging way. Experimental archaeology has an important contribution to make to the achievement of both of these goals. For example it may help us to understand how a building represented only by postholes was constructed, while experimental replication helps us to understand how things were made and used in the past. In particular the microscopic wear traces produced by known experimental activities can be compared with those found on ancient tools. Experiment also helps us to understand how the archaeological record is formed: how artefacts are transported by rivers, the changes that take place when a soil is buried or an earthwork weathers, and the inclusion of micro-traces in the sediments of archaeological sites as a result of specific activities. Like all rigorous scientific methodologies, archaeological experiments seek to control variables in order to make precise measurements concerning those elements of particular interest or importance. For instance, excavations may be conducted at defined intervals to measure how an earthwork changes over time. The key is that good experiments are those which are carried out to test particular theories or hypotheses about the past. They are one of the ways in which archaeologists are developing more explicitly scientific methodologies, appropriate to understanding the particular characteristics of the archaeological record. In archaeology, experiments and hypothesis testing seldom provide proof that one particular theory is correct but they may very well enable that theory to be accepted or refined pending further critical enquiry. Good science is always questioning, always looking for a better answer. Experimental sites can be an important arena in which archaeologists can think critically about the formation processes of their record and put theories to the test in a way that also contributes to education and outreach.
Experimental archaeology at Reading Recent years have seen an increasing focus upon experimental archaeology at the University of Reading’s Department of Archaeology. Research by Professor Martin Bell, Dr Wendy Matthews, Professor Steven Mithen, and Dr Rob Hosfield, amongst others, has utilized experimental approaches, with projects exploring topics ranging from handaxe butchery to the modification of buried soils. This research has involved a mixture of academic staff, doctoral research students and undergraduate students, with experimental archaeology helping to engage dissertation students with practical and science-based archaeology. In 2007–9 the School of Human & Environmental Sciences at the University of Reading is supporting a new project, Developing Experimental Approaches in Archaeology, designed to explore ways of developing experimental archaeological approaches in our research and teaching. The project is led by Professor Martin Bell and Dr Rob Hosfield and also involves Rowena Banerjea, Dr Alex Brown, Professor Stephen Nortcliff and Dr Wendy Matthews, drawing together the Department and the School’s research expertise in experimental archaeology. The project is also developing new inter-disciplinary links (including colleagues from the School of Human & Environmental Sciences at Reading, and other UK and European experimental archaeological sites), and conducting new pilot research projects in experimental archaeology.
Butser Ancient Farm
Butser Ancient Farm was set up by the late Dr Peter Reynolds in 1972, near Petersfield in Hampshire. Since then it has focused mainly on issues of Iron Age archaeology and has played an important part in developing understanding of the construction of roundhouses, grain storage in pits, crop yields, and weed floras, and has increased understanding of many other aspects of the archaeological record. Since Dr Reynolds’ death in 2001 Butser has continued to develop, with the addition of a Roman villa created as part of a Discovery Channel television series. Butser has also been more influential than Peter Reynolds may ever have envisaged: many of the comparable prehistoric experimental sites in Britain are based quite closely on the model he created at Butser. For more information on Butser, including opening times, see: www.butser.org.uk
Roman metal working, weapons and body armour
This booklet introduces aspects of the experimental archaeology with which we are involved at Reading, and offers our observations about how experiment in archaeology may be developed more widely in the future. Our purpose is to encourage a renewal of interest and involvement in experimental archaeology, and to stimulate students to think about possible experimental questions and projects for dissertation and doctoral research at both undergraduate and postgraduate levels.
Dr David Sim is a skilled professional blacksmith and archaeologist who did his PhD at Reading on Roman iron working. He has carried out experimental studies of the production methods and effectiveness of weapons such as the Dacian battle scythe, and Roman armour. Dr David Sim gives demonstrations of iron working at the Silchester field school in July each year. For more information about the field school and its open days see: www.silchester.reading.ac.uk
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Experimental archaeology in teaching and learning Experimental archaeological sites and projects offer ideal contexts for teaching and create excellent possibilities for synergies between teaching and research. The opportunity to observe examples of buried soils formed over a known period of time under known conditions has been especially invaluable to our MSc Geoarchaeology students here at Reading, while experimental contexts focus the mind of the fieldworker on the formation processes of the record under excavation.
Mesolithic tools, foods and structures Martin Bell & Steven Mithen Preparing the report (Bell 2007) on our recent campaign of excavations on Mesolithic sites in the Severn Estuary threw up all sorts of questions about how things were made and done in this period which could be partly addressed using experimental methods. We subsequently organised a Mesolithic experimental weekend at Butser, involving Reading students and volunteers in a mixture of teaching and research activities (below left). In our Severn Estuary excavations we had found artefact distributions suggesting the existence of small, circular tepee-like structures. Our work at Butser showed that such a structure could be erected in less than a day and could provide sleeping accommodation for a nuclear family of 4 or 5. Our excavations had also produced many heat-fractured stones and we discovered that these provided a very effective way of cooking a salmon. We also conducted experiments replicating the wear traces left on bone artefacts used to prepare hides and work wood: these were helpful in interpreting the wear traces found on our Mesolithic bones. Although these were only small-scale, two day experiments (which we would like to take further) the exercise was extremely valuable, at a key stage in the post-excavation process, for thinking through in a practical way some of the problems of interpretation. Experimental methods were also similarly important in another of our Mesolithic projects: Professor Mithen’s Southern Hebrides Project (Mithen 2001). Here a series of experiments explored flint knapping, tool manufacture and usages, and food preparation. Once again the experimental results aided in the interpretation of the project: for example the hazelnut roasting suggested that the most effective ovens are relatively shallow pits (combined with limited roasting times), and suitably small pits were identified at the site of Staosnaig (below left). The manufacture of an ‘Obanian’ harpoon took a total of six hours, suggesting that such items were curated, but also revealed that the required techniques could be quickly discovered and mastered with limited practice (arguing against the need for specific antler crafts‘men’).
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Experimental archaeology and student research Experiments can also form the core of first rate student dissertation topics at all levels, promoting well-defined problems, providing opportunities to combine field and laboratory work, and producing original and innovative data amenable to robust graphical and statistical analysis and interpretation. In the last few years there have been increasing numbers of experimental archaeological research projects undertaken by Reading Archaeology undergraduate and postgraduate students. Recent and current examples include investigations of:
• The role of spoken language in the learning of basic knapping skills (Adam Donnelly) • Handaxe manufacturing decisions as evident in refitting sequences from replicated examples (Faye Nash) The following pages include short summaries of four student projects in particular: experimental archery exploring the effectiveness of later prehistoric arrowheads (Tom Williams); experimental use-wear analysis investigating the functions of Early Neolithic ‘projectile points’ (Dr Sam Smith); woodworking experiments with later prehistoric axes (Anna Ward); and experimental butchery assessing the impact of varying handaxe symmetry upon performance (Dr Anna Machin).
• The geoarchaeological and forensic properties of pits (Robert Power) The effectiveness of later prehistoric arrowheads (Tom Williams) A 2007/8 undergraduate dissertation by Tom Williams (BA Archaeology, 2005–2008) used experimental archaeology to investigate the effectiveness of different types of flint arrowheads from the Neolithic and early Bronze Age periods. The experimental research formed part of a wider investigation into later prehistoric arrowheads, including the form vs. function debate and the potential of the individual types to function as effective projectile points. The experiments specifically explored: • The penetration and accuracy of the arrowheads • The potential for re-use of the arrowheads and the nature of their user-wear and damage
ratings, generating similar draw weights and characteristics to later prehistoric bows. The target was a pig carcass (representing a typical later prehistoric hunted species), with each arrowhead type shot from each of the three longbows over 20 yards range. Arrowhead accuracy (hit/miss) and penetration depths were measured. The experimental results provided a number of valuable insights into each arrowhead type: • 25 out of 82 arrows shot hit the target (30% success rate) • Average penetration was 15.87cm
• The relationships between the effectiveness of arrowhead types and bow poundage
• The barbed and tanged arrowheads were the most effective (measured by accuracy and penetration) across all three bows
The experiments used a range of replica arrowhead types knapped by John Lord (barbed and tanged, chisel, oblique, and petit tranchet), hafted with bitumen and nettle fibre rope onto modern shafts with modern fletchings (to reduce the number of experimental variables). The arrows were shot from three modern longbows with different poundage
The experiments suggested that barbed and tanged arrowheads were the most effective and represent an ‘optimum’ later prehistoric design. This supports the concept of evolutionary development in flint arrowhead design and challenges earlier suggestions of the non-utilitarian role of barbed and tanged arrowheads based on funerary associations.
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Making and using stone tools (Sam Smith) Sam Smith’s doctoral research (2000–2006) undertook a detailed study of chipped stone points from Early Neolithic (c. 11,500 BP) sites in Southern Jordan. Traditionally, the function of many of these pieces had been assumed to correlate with typological classes, for example ‘projectile points’ were assumed to have been arrowheads. The research tested this assumption through a microscopic examination of tool edges, in an attempt to ascertain their function. A key aspect involved a programme of experimental replication of point manufacture and use. Working with the skilled flint knapper John Lord, Sam created several hundred replica tools and used them for a range of tasks. The experiments indicated that the wear traces found on many of the archaeological ‘projectile points’ were actually the result of them being used as drill bits or perforators. These conclusions facilitated a new understanding of this artefact type and have significant implications for the interpretation of Early Neolithic chipped stone assemblages.
Distinguishing axes through woodworking (Anna Ward) Anna Ward prepared her 2006/7 undergraduate dissertation on an experimental study of the facets left on wood worked with replica later prehistoric axes of flint, bronze and iron, combined with an analysis of the woodchips and other debris produced by pointing hazel roundwood billets using the different tool types. Facets produced by using a bronze axe were closely comparable to those on Bronze Age timbers from the Severn Estuary. Digital microscope photography was used to record the facets produced by flake removals and metrical analysis was carried out on the facet and chip dimensions. The data produced was examined statistically enabling Anna to accept the validity of the two hypotheses posed at the outset: that both the facets and debris produced by different types of axe can be distinguished. This is important because wood worked with particular metals (eg. copper or iron) is not infrequently attested well before the earliest dated use of implements of those metals in specific areas. This is presumably because of the curation and re-use of materials: the wood evidence can thus provide a new perspective on dates of material culture change in particular places. 6
The implications of handaxe symetry for experimental butchery (Anna Machin) As part of her doctoral research (2003–2006) Dr Anna Machin sought to establish clearly the relationships between the degree of handaxe symmetry and their effectiveness as butchery tools, through large-scale, controlled experiments. The experimental methodology included a series of quantitative and qualitative components: • 30 fallow deer were butchered (ages and weights were restricted to animals under 2 years old and 50– 60 lbs to reduce carcass variability). • The methods used by each butcher (a professional game butcher and a Palaeolithic archaeologist) were distinct but internally consistent. • The handaxes were all capable of butchery (i.e. all had a length of cutting edge) but all exhibited variability in frontal and side symmetry (measured digitally after Marshall et al. 2002). • Handaxe morphology and dimensions were also recorded. • The butchery sessions were videotaped and logged, generating butchery timing data for each carcass and the individual activities (e.g. skinning, filleting etc). • The butchers also “thought aloud” to produce a verbatim record, and scored each handaxe (e.g. weight distribution; ease of use). The timing data were modelled to remove the impact of increasing butchery skills over the course of the experiments. Regression analyses and rank correlation were applied to the resultant data: • There was only partial evidence that increasing frontal symmetry increases the effectiveness (i.e. reduced butchery times) of handaxes as butchery tools.
The statistical analyses of the data suggested some influence of frontal symmetry upon handaxe effectiveness. However, there are several qualifiers concerning replicability, outlier exclusions, and the strength of the observed relationships. The partial influences may reflect slight gains in efficiency linked to the reduced amount of time it takes to locate a good handhold on a symmetrical handaxe following rotation, or that certain butchery methods render symmetry advantageous. In summary, factors other than functional considerations for animal butchery may be playing a key role in the decisions by hominin stone knappers to impose high degrees of symmetry on some of their handaxes.
• These results were also mitigated by a series of factors, including the removal of outliers from the data-sets (Machin et al. 2007), and the limited replication of significant results (for the role of symmetry) across the data sets for both butchers. • The majority of the variation in butchery time could not be explained by any of the handaxe morphology variables. • Although side symmetry was not statistically significant for butchery, the verbatim record did refer to the importance of cutting edge symmetry (e.g. ‘the angle I’m finding really hard because it’s kind of asymmetrical’) and other aspects (e.g. degree of refinement, angle, degree of curve) which may contribute to the unexplained variation.
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Experimental approaches and the formation of the archaeological record Recent research at Reading has highlighted the contributions which experimental approaches can make to our understanding of the formation and modification of the archaeological record, whether dealing with built structures (ranging from the construction and destruction of buildings to the sedimentary, micromorphological and biological evidence for human activities within them) or artefact scatters associated with structures and activity areas.
Archaeological buildings: the Longbridge Deverill Roundhouse Martin Bell In 2006 the main roundhouse at Butser Ancient Farm, the Longbridge Deverill Cowdown roundhouse, began to collapse. As it was dismantled we had the opportunity to carry out the small-scale excavation of a trench across the structure (below left). These excavations enabled us to explore the hypothesis that the structure may have failed just 14 years after construction because, due to timber availability when it was made, the inner post ring of this double ring roundhouse was of ash rather than oak: the latter would have lasted longer. Notably, the two inner posts we sectioned had rotted and cracked just below the ground surface. The building was originally erected on the surface of a ploughed field without a terrace being created. The floor had stones evenly dispersed through the top 20cm as a result of earlier cultivation, whereas outside the building, where the surface had since been vegetated, a 40mm thick earthworm-sorted stonefree horizon had formed over the previous 14 years. A central hearth created on the roundhouse’s ground surface had been in very regular use over the 14 year life of the building, and when sectioned it showed remarkably superficial sub-surface traces of heat reddening. Charcoal was sparse and the maximum depth visibly affected by heat was 130mm. The trampled floor only retained its distinctive form where protected from the elements; where wetting and drying occurred subsequent to the removal of the roof, earthworms had begun to appear and trampled floor layers were indistinct after just a few weeks exposure. Overall, many traces of the building such as the floor, hearth, wattlework, and drip feature from the roof produced only superficial traces which might not survive over archaeological timescales, especially if the site was subsequently cultivated. In May 2008 we obtained a small number of comparable samples from experimental structures at the Somerset Levels and Moors Centre (these structures are based on buildings originally excavated at Glastonbury Lake Village).
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Life-history of buildings and site-formation processes Wendy Matthews, Stephen Nortcliff, Alex Brown & Rowena Banerjea Studies of traditional architecture suggest that archaeologists can readily identify activity areas and explore the creation of social settings and the histories of events within buildings and settlements through greater attention to the study of architectural surfaces and micro-residues in sediments, where preservation is sufficiently good. Microstratigraphic and micromorphological analyses enable high-resolution analysis of four independent lines of inquiry in the study of the life-history of buildings: • The origin, manufacture and properties/affordances of building materials and surfaces on floors, platforms, walls and, potentially, ceilings in upstanding buildings. • The impact of activities and natural agencies on these surfaces, including impressions of mats and floor coverings. • The multiple biographies of the mineral, biological and artefactual micro-residues on surfaces through in situ micro-contextual study of the traces of the pre-depositional and depositional histories of each component including: source material, abrasion, fragmentation and burning.
• Elemental enrichment in metal-working areas The outputs of these experimental analyses are being compared to multi-period archaeological sites, including Silchester and Çatalhöyük. A wide range of interdisciplinary experimental and ethnoarchaeological research is being conducted by the international team at the Neolithic site of Çatalhöyük in Turkey in order to widen our knowledge of materials, architecture and environment. This work, conducted with the local community, includes construction of an experimental house (www.catalhoyuk.com). Such studies of traditional practices and knowledge are urgently needed in the face of rapid urbanisation and environmental change. These are particularly vital to our understanding of the interrelationships between different materials, activities and ecological zones over seasonal, annual, and longerterm cycles. Research at Reading has included study of: the properties, technology and life-histories of architectural materials and buildings; animal penning; and the sources and combustion of different types of fuel for food preparation and cooking.
Thin section (B) from Building 2, Çatalhöyük (A), showing plaster floor (1) and fuel raked out: charred wood (2) and dung ash (3).
• On-going post-depositional histories. Recent geoarchaeological and palaeoenvironmental analyses have highlighted a series of major problems in the interpretation of material assemblages, siteformation processes and settlement space. Central to these problems are the wide range of variables that affect pre-depositional, depositional and post-depositional histories of micro-artefacts, sediments, plant remains and organic matter, including: environment, human agency, materials and timescales. Current research at Reading is seeking to identify these variables and design research strategies for their measurement and examination through inter-disciplinary and multi-proxy characterisation of experimental archaeological spaces and taphonomic processes. Our experimental analyses are specifically focusing upon:
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• Improved interpretation of soil micromorphology on archaeological sites by establishing key comparative data sets • Taphonomy of phytolith and pollen assemblages • The nature and taphonomy of organic matter and black carbon using 13C NMR and BPCA Black Carbon analysis
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Sampling buildings and activities at Lejre, Denmark Rowena Banerjea In August 2007, research student Rowena Banerjea carried out fieldwork at Lejre Historical and Archaeological Research Centre, Denmark (www.lejre-centre. dk) as part of the Life-history of buildings and siteformation processes project. Her work is generating experimental data to compare with early Roman occupation deposits from Insula IX at Silchester (Hampshire, UK). The fieldwork samples targeted soil micromorphological (Banerjea) and plant micro-fossil (Banerjea and Dr. Alex Brown) assemblages, geochemical traces (Banerjea), and the nature of organic matter (Prof. Stephen Nortcliff) in activity-related occupation deposits within experimental archaeological buildings. Samples were collected from two buildings within the reconstructed Iron Age village: the disused ironworking forge (right) and the ‘peasants’ building. With the latter were a disused cattle stable (in use 1965–early 1980’s), a crop grinding area and a hearth used for heating and cooking. Building materials such as daub, thatch and straw were also collected as reference materials.
In addition to the geoarchaeological sampling, consultations with the Lejre staff documented the construction, repairs to, and decline of, the individual buildings and the duration and frequency of the range of activities which took place within them. The outputs of these consultations will assist in formulating a framework for future experimental archaeological research which analyses activity areas and the formation processes of archaeological deposits within buildings.
Pollen, phytoliths and human activities Rowena Banerjea & Alex Brown
Buildings within the reconstructed Viking village provided an excellent opportunity to study the changing use of space and spatial variations in occupation deposits, due to differing stages of building collapse. A sunken-shack (below left) previously used for goat and sheep penning and bone-working was sampled, with roof failure resulting in soil development across half of the structure (below right).
Pollen dispersal by wind and insects results in its trapping within soils and sediments as they accumulate over time. Where pollen is preserved in oxygen-free (anaerobic) conditions, it can be analysed to reconstruct past vegetation and the activities of humans in the landscape over a variety of timescales and, in this research, to understand past rural and urban settlement ecologies.
The comparative analysis of experimental archaeological samples, archaeological occupation deposits, and external controls will provide valuable information regarding the taphonomy of micro-refuse and plant micro-fossil assemblages in the archaeological record, as well as increasing knowledge of the geochemical enrichment and behaviour of phosphate and heavy metals in activity areas (e.g. metalworking and stabling).
Phytoliths form in the cellular skeleton of plant tissue from the silica which is deposited while the plant is alive. As plants decay the mineralised cells (phytoliths) remain in the soil, resulting in a localised distribution which is particularly useful for identifying ancient activity areas which have utilised plants. Experimental analyses play an important role in understanding the depositional pathways and formation processes of pollen and phytolith records in modern occupation
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deposits, as an aid to investigating traces of activities in a diverse range of archaeological settlement contexts. Pollen samples have been analysed from Lejre and Butser. At Lejre the Iron Age Zone building 2 and the Viking Age sunken hut include stable areas for cattle (IA zone) and sheep and goat (VA zone). High levels of grass pollen were recorded in both samples, most likely derived from grasses growing in proximity to these buildings and blown through the entrances, but it is also included in the animal dung (VA zone) that litters the floors. Cereal pollen in Iron Age building 2 is most probably derived from hay used as cattle fodder. The Viking Age sunken hut also produced two grains of Cannabis pollen, derived either from a herb patch 30m away, or resulting from hemp production. Samples from the Longbridge Deverill roundhouse at Butser include significant amounts of cereal pollen (entrance and internal eaves samples), and are closely related to areas of crop processing (entrance) and storage of thatch and hay (internal eaves). The hut floor is a compacted agricultural soil rather than a prepared surface, so the cereal pollen may derive from agricultural activities prior to the construction of the roundhouse. However, analysis of the floor sample did not produce any cereal pollen, so it is probable that the cereal pollen recorded elsewhere relates to specific activities/activity areas within the roundhouse. This is being tested through analysis of further samples within the roundhouse, from the buried soil exposed beneath the boundary bank, and from external control samples. Phytolith analysis will help to test the pollen observations, as this technique enables cells from different parts of the plant to be identified (e.g. husks from crop processing activities). Soil micromorphology and analysis of control samples will assist with understanding the depositional pathways of plant remains in these various contexts, in particular when deciphering assemblages that may consist of a mixture of residual plant remains from falling thatch, animal dung, animal fodder and crop processing activities.
Destruction by fire Karl Harrison Karl Harrison is a part-time PhD student at Reading who works as a professional forensic scientist. As part of his forensic work he has had to investigate burnt structures and develop an understanding of the sequence of events which produce the observable traces of fire. His doctoral research involves investigating the effects of fire on structures. Karl uses modern fire science techniques to help interpret the evidence of burnt structures in the archaeological record, and archaeological approaches to stratigraphic excavation to inform the development of new methods for the forensic investigation of fire. Burnt experimental structures have been an important element in developing this approach, especially a construction based on an Anglo-Saxon sunken floor building at West Stow, Suffolk, which was recently burnt down, apparently by arson. Karl and a team from West Stow were able to carry out one of the first detailed recording exercises of a burnt ‘archaeological’ structure, which has enabled him to document a detailed reconstruction of the course of the fire and the physical effects of its various stages, including modifications of the magnetic properties of the adjacent soils.
(Left) Rowena Banerjea sampling the floor of the Longbridge Deverill roundhouse at Butser for pollen and phytoliths.
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Experimental earthworks Martin Bell These experiments have played an important role in developing our understanding of how soils and the biological evidence within them change as a result of burial. Other related research questions concern the investigation of the decay and preservation processes affecting buried artefacts, and the processes of erosion and sedimentation affecting bank and ditch earthworks themselves. Of particular significance in this area of research have been two linear experimental earthworks: Overton, Wiltshire (constructed in 1960 on chalk) and Wareham, Dorset (in a sandy heathland environment). Professor Martin Bell has been responsible for the most recent excavations of both of these earthworks. A second generation of octagonal experimental earthworks were set up by Peter Reynolds in the mid 1980s. Those experiments were principally concerned with vegetation colonisation, weathering and sedimentation in relation to aspect, hence the octagonal form. Although relatively little has been published on the octagonal earthworks to date, we are now embarked on a programme of excavations to look at the buried soils, earthwork erosion and ditch sediments at these sites. An earthwork on Upper Chalk within the present day Butser site at Bascombe was subject to small-scale excavation by Reading students 16 years after construction, in December 2007. The buried soil had been cultivated up to the point of burial and was low in organic matter, making it unattractive for faunal activity, such as earthworm sorting and mixing.
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The analytical properties of the buried soil are currently being investigated at Reading by Amy Poole and Chris Speed as part of research into the chemistry of buried soils. The surface of the bank showed the early stages of soil development and humus incorporation and there were clear signs of calcium carbonate leaching and deposition within the bank. The ditch sediments were markedly asymmetrical with a greater volume of sediment coming from the outside than from the bank side. This confirms earlier observations by Peter Reynolds and is the opposite of what archaeologists normally expect. The probable explanation concerns aspect and compass direction, emphasising the significance which Reynolds attached to this parameter in his original design for the octagonal experiments. Further work will be following up these investigations with excavation of the octagonal earthwork (on brickearth over clay) which Reynolds’ created in 1986 at the Roman Palace site at Fishbourne, West Sussex. This will provide an opportunity to observe, record, and analyse a buried soil of a type not previously investigated experimentally, and to record the weathering and sedimentation process of the bank and ditch. An earthwork constructed on Lower Chalk at Wroughton, Wiltshire has also recently been investigated by Emma Gilbert for her MSc Geoarchaeology dissertation. She compared the micromorphology, chemistry, land snails, and earthworm granules in the 20 year old buried soil with those in the present-day unburied soil. Like Overton, Wroughton highlighted the significance of vegetation matt and soil chemistry for molluscan presence and survival, even on sites of calcareous bedrock: under certain vegetation condi-
tions, periods of stasis will be under-emphasised and periods of calcareous subsoil disturbance over-represented in the molluscan record. This earthwork research has emphasised the role of faunal agency, particularly earthworms, in the formation of the archaeological record, thus revisiting the pioneering earthworm research of Charles Darwin which has been a formative influence on the development of experimental geoarchaeology.
Artefact scatters in slope environments Rob Hosfield A key branch of experimental archaeology has concerned the modification of artefact scatters and applications of the resulting data to taphonomic interpretations. While an important element concerns the fluvial transportation of lithic artefacts (e.g. Hosfield & Chambers 2005), there is also the issue of artefact supply from fluvial floodplain and valley slope surfaces into active channel zones. Recent research has therefore been undertaken as a first step in seeking to improve understanding of the potential time-lags between artefact discard (behaviour) and their fluvial re-deposition (assemblage formation). This work is exploring the re-working of multi-period/ multi-material artefact scatters on low-angled slopes within a lowland river valley environment. The experiments were conducted at the University of Reading’s farm site at Sonning, on the southern floodplain and lower terraces of the Middle Thames. The experimental artefact sets included replica flint flakes, Roman ceramic building material fragments, and Roman pottery fragments, derived from spoil heap material (at the University’s Silchester excavations) and experimental knapping programmes. The artefacts were emplaced in October 2007 on a low-angled terrace slope, which was a mixture of exposed plough soil and low agricultural scrub. Recording and monitoring of the artefacts between October 2007 and February 2008 indicated no movement of any of the scatters, despite varying climatic conditions during this period and the range of artefact sizes and weights. There was also very little evidence of artefact fragmentation.
The low-angled experimental slope and an experimental lithic scatter at Sonning Farm, Reading.
The results of this pilot experiment indicated the potential stability of different artefact scatters upon a partially-exposed low-angled slope surface during interglacial-type autumnal and winter conditions at 50° latitude. Further studies will continue to explore artefact movement in different climatic (e.g. periglacial) and topographic (e.g. steeply angled slopes) settings, and over longer time-spans.
Opposite page: Professor Stephen Nortcliff and Dr Wendy Matthews discuss the 16 year old buried soil below the Butser octagonal earthwork (left). The soil buried for 20 years by the Wroughton octagonal earthwork and investigated for Emma Gilbert’s MSc dissertation (right).
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New horizons and collaborations Experimental crop growing Emma Jenkins The Water, Life and Civilisation project’s crop growing experiments are being conducted in Jordan in collaboration with NCARTT (National Centre for Agricultural Research and Technology Transfer). They are designed to evaluate and develop Rosen & Weiner’s (1994) proposal that the number of con-joined cells in multicelled wheat phytoliths can be indicative of irrigation, by introducing additional variables into the experimental design which Rosen and Weiner employed.
Garden Agriculture on Easter Island (Louise Jones)
Recent and ongoing multidisciplinary research into garden agriculture on Easter Island, in particular the use of rocks (both on the ground surface and as a lithic mulch), is contributing towards ongoing debates into the adaptive responses to natural and/or anthropogenic environmental change, landscape management, and issues of sustainability. Louise Jones’ MSc Geoarchaeology dissertation research is using multiple geoarchaeological methods combining pollen, phytolith and starch residue analysis to identify the crop plants grown in archaeological gardens, with micromorphological analysis of the soils’ microstructure and inclusions identifying features not observable at the macro-scale. By comparing samples from archaeological garden sites located on exposed slopes (and subject to disturbance from cows, horses, and people) with a restored archaeological garden (surrounded by trees, containing crop plants and protected from disturbance), this research is examining differences in the archaeological record and therefore key issues of preservation and interpretation.
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Three different crops are being grown: durum wheat (T. durum), common barley (H. vulgare) and sorghum (Sorghum halapense). In the first year of experimentation these were grown under four different irrigation regimes: no irrigation (0% of the crop water requirements), sub-optimal irrigation (80% of the crop water requirements), optimal irrigation (100% of the crop water requirements) and over-optimal irrigation (120% of the crop water requirements); in the second and third year an additional sub-optimal category of 40% was added. The experiments are being conducted in three different crop growing stations: Khirbet al-Samra is located to the northeast of Amman and has an annual rainfall of approximately 150mm per year; Ramtha is in Northern Jordan and has approximately 300–350mm rainfall per year; and Deir ‘Alla is in the Jordan valley and has approximately 250mm of rain per year. Each plot measures 5m x 5m with a space of 1.5m between plots. A drip irrigation system is employed and reclaimed waste water is used at Khirbet al-Samra and Ramtha whilst mixed water is used at Deir ‘Alla. Water analyses were conducted before experimentation began, showing that the water was within the Jordanian standards for use in crop irrigation. Meteorological data are available for all three stations and soil samples were taken from the plots prior to and during each year of experimentation. The experiments are currently ongoing: for up-to-date news see the project website: www.waterlifecivilisation.org.
The way forward Perhaps the most important role which experimental archaeological sites play is educational and experiential, helping school children and the public to think about past ways of life in a tangible and accessible way. We are often told by undergraduates that their interest in archaeology was sparked by a visit to such a site. The prominence of experimental sites and activities in archaeological television programmes also highlights their key role in archaeological outreach. The Developing Experimental Approaches in Archaeology project has enabled us to take stock of the current state of experimental archaeology in Britain and to form the view that more needs to be done to encourage active engagement between the research community and experimental sites. Experimental sites are of huge importance in terms of education and outreach but those running them are often concerned that the demands of these roles leave little opportunity, or resources, for active experimentation. Yet an active experimental programme is clearly an important part of what makes these sites interesting for children and the public alike. We feel that one solution is to encourage university and other research organisations to make more active use of the resource represented by experimental archaeology sites. As we demonstrate in this booklet these sites are excellent venues for learning how to excavate, appreciating how the archaeological record forms, and carrying out
References Bell, M. 2007. Prehistoric Coastal Communities: The Mesolithic in Western Britain. Council for British Archaeology Research Report No. 149. York: CBA. Hosfield, R.T. & Chambers, J.C. 2005. River gravels and flakes: new experiments in site formation, stone tool transportation and transformation. In M. Fansa (ed.) Experimentelle Archäologie in Europa, Bilanz 2004, Heft 3: 57–74. Isensee Oldenburg: Verlag. Machin, A.J., Hosfield, R.T. & Mithen, S.J. 2007. Why are some handaxes symmetrical? Testing the influence of handaxe morphology on butchery effectiveness. Journal of Archaeological Science 34: 883–893. Marshall, G.D., Gamble, C.S., Roe, D.A. & Dupplaw, D. 2002. Lower Palaeolithic technology, raw material and population ecology. http:// ads.ahds.ac.uk/catalogue/specColl/bifaces/index.cfm (10 January 2005). Mithen, S. (eds.) 2001. Hunter-gatherer landscape archaeology: the Southern Hebrides Mesolithic project, 1988–1998. Cambridge: McDonald Institute for Archaeological Research. Rosen, A.M. & Weiner, S. 1994. Identifying ancient irrigation: a new method using opaline phytoliths from emmer wheat. Journal of Archaeological Science 21: 125–132.
original dissertation and doctoral research. It is this objective of encouraging more experimental activity through sites such as Butser that motivated the project’s one day workshop (to be held at Butser Ancient Farm in June 2008). The goal of the workshop is to provide a context in which representatives from experimental archaeological sites can explore key issues for the future of experimental archaeology: means by which experimental work can be encouraged at heritage sites, developing contributions from academic research staff into experimental projects, identifying and promoting opportunities for student dissertation research and field experience, and exploring relationships between higher levels of experimental activity, the development of the sites, and the provision of funding. We hope that a key output of the workshop will be contributions to the development of best practice and the growth of beneficial links between the experimental sites themselves, and a summary of the workshop discussions will be posted on our project website (post-July 31st 2008): www.reading.ac.uk/SHESresearch/Archaeology/Science/ Experimental.html Two papers summarising aspects of our current experimental research at Reading are also to be presented at the World Archaeological Congress in Dublin in July 2008 and we hope that these papers and the circulation of this booklet will also help to stimulate international discussions concerning the way forward for experimental archaeology.
Contact details Professor Bell, Dr Matthews, Professor Nortcliff, Dr Hosfield and Professor Mithen would all be delighted to talk to potential doctoral research students about possible PhD topics in experimental archaeology (Bell, Hosfield, Matthews, Mithen) and soil science (Nortcliff). For more information about our undergraduate and postgraduate degrees, please contact: SHES Teaching Office Geoscience Building University of Reading Whiteknights Box 227 Reading, RG6 6AB
[email protected] Tel +44 �0�118 378 7966
[email protected] Tel +44 �0�118 378 6713 This document is © Copyright University of Reading 2008. It was designed by Frances Taylor and printed in June 2008 by Herald Graphics.
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Acknowledgements We are grateful to Christine Shaw, Steve Dyer, Maureen Page, Simon Jay, Joyce Herve, and Dai Morgan-Evans for facilitating and encouraging our work at Butser. We are also grateful for collaboration from the Science Museum (Wroughton), Fishbourne Roman Palace, West Stow Country Park, and Somerset County Council: Levels and Moors Centre, and the Çatalhöyük Research Project. Rowena Banerjea acknowledges funding and collaboration with Lejre Archaeological and Historical Research Centre, Denmark. Thanks also to all of the Reading undergraduate and postgraduate students and other volunteers who have been involved in these experiments. Earlier work on the Overton and Wareham experimental earthworks was funded by NERC and English Heritage. For their involvement in, and support of, the experimental handaxe butchery project, thanks
Reading Archaeology For further details about the Developing Experimental Approaches in Archaeology project or other experimental archaeological work at the University of Reading, please contact: Professor Martin Bell (
[email protected]) Dr Rob Hosfield (
[email protected]) Department of Archaeology University of Reading Whiteknights Box 227 Reading, RG6 6AB
[email protected] Tel +44 �0�118 378 7966 www.reading.ac.uk/archaeology
to the butchers (David John and Dr Matt Pope), Dr Gil Marshall (handaxe symmetry measures), Colin Grayer (Statistical Services Centre, University of Reading), John Lord (the experimental handaxe assemblage), and the British Academy (Small Research Grant SG-40888). Rob Hosfield would also like to thank James Lamburn (Sonning Farm Director, University of Reading) for permitting access to the Sonning Farm site as part of the experimental scatters work, and to Rebecca Kiff (Crops Research Unit, University of Reading) for supplying data from the Sonning and University weather stations. Images for Karl Harrison’s text supplied by West Stow AngloSaxon Village and St. Edmunds Burough Council. The Developing Experimental Approaches in Archaeology project has been funded by the School of Human & Environmental Sciences, the University of Reading.
