Bounded, dense, impish, intense … the Isle of Wight

Bounded, dense, impish, intense … all words which surfaced in discussions about the Isle of Wight when Miranda and Anwen met up with local researchers to discuss the potential shape of the Englaid project case study.

Binstead beach, north Wight
Binstead beach, north Wight
St Lawrence beach, south Wight
St Lawrence beach, south Wight

During a fleeting visit, we traversed the island, trying to absorb its tremendous variability. We traveled from a benign north coast, where England felt so close and where wooden trackways, fish traps and post alignments have been assembled in the intertidal mud since the Neolithic period, to an almost malevolent southern one, where Iron Age and Roman burials have been recovered, numerous ships have been wrecked, and where the sea was whipping itself up into a weekend storm. We were struck by the strong presence of the geological basis of the island, running broadly in strips from east to west. Yet it was also clear (and became more so through our discussions with researchers) that the east and west of the island had distinct characters – closed and open, respectively, in feel.

Lines made with undercliff clay and sandstone
Lines made with undercliff clay and sandstone

We focused on some of the island’s fabrics – clay, sandstone, limestone, chalk, flint. Miranda drew lines with beach clay and mudstone.

Sandstone outcrop, Brighstone
Sandstone outcrop, Brighstone

This fiery sandstone outcrop caught Anwen’s eye as we flashed by.

Pebble in the undercliff clay
Pebble in the undercliff clay
Pebble made from undercliff clay
Pebble made from undercliff clay

We were impressed by the force represented by the sea and pebble battered clay along the undercliff coast – pebbles pressed into the clay and even clay pebble pummeled out of its matrix.

Flint, sandstone, limestone, chalk, clay - farm building at Alverstone
Flint, sandstone, limestone, chalk, clay – farm building at Alverstone
Clay, flint and limestone rubble - Brading Roman villa
Clay, flint and limestone rubble – Brading Roman villa

Also striking was how materials gathered from across the island’s landscapes were assembled in its architecture – in Roman villas and more recent farm buildings. The Isle of Wight landscape, and islanders’ relationships with this landscape were apparently condensed within its buildings.

Isle of Wight researchers
Isle of Wight researchers

During our very productive discussions with researchers Frank and Vicky Basford, Becky Loader, Rosie Edmunds and Owen Cambridge we were able to crystalise some of these thoughts. We discussed the rapid rate at which finds data, particularly coins, are currently being produced on the island; how having a distinct edge (the coast) had affected the character and development of the island’s archaeology; and how islander’s contacts with mainlanders on both sides of the Channel had toed and froed over our study period. We came away armed with further lines of enquiry to follow, a plastic bag of bluish clay, some rapidly penciled line drawings, and an appetite to return for a more sustained visit!

Extracting trends (VII)

Further to my previous post, I have now had another go at constructing trend surfaces for the four broad main periods covered by this project.  This time, however, I have filtered out records that are explicitly related only to artefact findspots (for each period).  This was in an attempt to downplay the influence in the previous trends from differential inclusion of PAS material between HERs.  The remaining records should, hopefully, thus primarily relate to sites with other archaeological evidence beyond just one or more artefacts.

Here are the results (to the same attribute scale as previous):

Trend surface for Bronze Age HER data, exc. findspots
Trend surface for Bronze Age HER data, exc. findspots
Trend surface for Iron Age HER data, exc. findspots
Trend surface for Iron Age HER data, exc. findspots
Trend surface for Roman HER data, exc. findspots
Trend surface for Roman HER data, exc. findspots
Trend surface for early medieval HER data, exc. findspots
Trend surface for early medieval HER data, exc. findspots

Comparing to the previous surfaces, we can see a general reduction in trend peaks, especially over Norfolk and Yorkshire.  The Bronze Age remains similar to previous; the Iron Age also, albeit with much lower peaks; the Roman period shows an increasing strength across Gloucestershire; the early medieval shows the most distinct reductions in eastern regions.

Chris Green

Extracting trends (VI) and national synthesis update

This post follows on from my previous posts on trend surface modelling (I)(II)(III)(IV)(V) and my posts on synthesis of multiple datasets using grid squares (I)(II)(III)(IV).

As our HER dataset is now nearly complete (only Merseyside is expected from now on; North Somerset and Bath & North East Somerset are unable to provide data), we are finally able to begin attempting to study the data which we have gathered on a nationwide scale.  Broad period classifications (Prehistoric; Bronze Age; Iron Age; Roman; early medieval; uncertain; “bad date” [i.e. outside our period]) were calculated for the HER data using a script (based upon the multitude of period designations applied by individual HERs or upon start / end dates) and the data was converted to shapefile format and merged into a single point layer.  This shapefile layer can then be very coarsely queried to produce distributions of records of different periods.

As an initial method for investigating this mass of data (around 400,000 records), I experimented with the production of a few trend surfaces.  First, one for all of the data received:

Trend surface for all EngLaId HER data
Trend surface for all EngLaId HER data

I think that there are two major factors at play in this trend.  The first is the general bias in English archaeology towards greater density of (probably) settlement and (certainly) fieldwork in the south and east of the country.  The second (possibly more dominant?) is the variation in recording methods used across the country.  Even where the same software is used, different HERs catalogue their data somewhat differently: some like to split everything up into individual periods and types, others like to collate into multi-period sites; some cast their nets wide to include as much data as possible (e.g. PAS data, MORPH data), others like to only include sites of certain and clear provenance.  This means that the density of data across the country is as much about modern practice as it is about activity in the ancient past.

We can then produce similar surfaces for our broad periods (all to the same numerical scale):

Trend surface for Bronze Age HER data
Trend surface for Bronze Age HER data
Trend surface for Iron Age HER data
Trend surface for Iron Age HER data
Trend surface for Roman HER data
Trend surface for Roman HER data
Trend surface for early medieval HER data
Trend surface for early medieval HER data

These four surfaces still reflect to some extent the differences seen in modern practice, but they are closer to the genuine distribution of past activity.  The Bronze Age surface seems to be biased towards uplands and towards Wessex.  The Iron Age surface has a clear bias towards the south east.  The Roman surface is biased towards lowland Britain but also towards the pockets of military activity in the north of England.  The early medieval surface is biased towards the eastern parts of England.

However, the distributions behind all of these trends are still heavily influenced by modern archaeological and CRM practices.  This is only going to get worse when we begin to produce duplication in our dataset by building in English Heritage NRHE data and other datasets.  As discussed in previous posts, one way in which to minimise these modern effects and reduce the influence of duplication is to collate data by 1 by 1 km grid cells.  This requires the application of a thesaurus containing simplified monument terms and the step already undertaken of assigning standardised period terms.  The result is a tessellation of 1 x 1 km grid squares across England recording the presence of different types of archaeological site for each of our broad periods, which we can then query and use to produce maps.

As an example, I constructed a few more trend surfaces, based upon the presence / absence of evidence for sites within our broad “domestic and civil” category.  This category includes: town, burh, civitas capital, colonia, hamlet, village, vicus, canabae legionis, oppidum, hillfort, anything defined using the word “settlement”, midden, timber platform (several of these sub-types belong to more than one broad category).  We can then look at how the underlying trends behind this category changed over time (these trend surfaces are logistic rather than linear, reflecting the probability of binary presence / absence relationship rather than density):

Trend surface (logistic) for synthesised data: Bronze Age "domestic and civil" category.
Trend surface (logistic) for synthesised data: Bronze Age “domestic and civil” category.
Trend surface (logistic) for synthesised data: Iron Age "domestic and civil" category.
Trend surface (logistic) for synthesised data: Iron Age “domestic and civil” category.
Trend surface (logistic) for synthesised data: Roman "domestic and civil" category.
Trend surface (logistic) for synthesised data: Roman “domestic and civil” category.
Trend surface (logistic) for synthesised data: early medieval "domestic and civil" category.
Trend surface (logistic) for synthesised data: early medieval “domestic and civil” category.

There is still some bias in these trend surfaces from the amount of data recorded by different modern archaeological entities (e.g. Northamptonshire is a very “completist” HER, which partially accounts for it showing up so strongly in many of the trend surfaces seen in this blog post), but the patterns are still quite interesting.  The Bronze Age is heavily influenced by the very high number of records present on Dartmoor and Bodmin Moor.  The Iron Age is probably mostly interesting for the low probability area across the “waist” of England from Cheshire to Lincolnshire.  The Roman is pretty much how I would expect it: high likelihood in the lowland zone and around Hadrian’s Wall (this includes “native” sites [whatever that means!] of Roman period date).  The early medieval is fairly flat, showing settlement across the country with greatest probability in central and eastern England (the peaks in Devon possibly need further investigation).

All of this is just a very preliminary, very coarse analysis of what is a very large and detailed set of data.  Some interesting patterns are beginning to emerge, but these may diminish as we continue to work on our material.

Chris Green

Happy Christmas and Thank You

Before we all sign off for Christmas, let us take this opportunity to thank the following HERs for kindly providing us with data over the last few months: Leicester City, Canterbury, Yorkshire Dales, Lake District, Plymouth, Nottinghamshire and Portsmouth. Special thanks must also go to Keith Westcott of ExeGesIS for helping with running the query in a few instances. This makes our HER data for the entire country almost complete!

Thanks as well to Helen Saunders from Essex HER for providing us with NMP data, and to Simon Crutchley, Lindsay Jones and Poppy Starkie for completing our NMP / NRHE data supply, and to Simon Crutchley and Mandy Roberts for taking the effort to visit us in Oxford. Finally, many thanks to the organisers of the HLC conference in London earlier this month for inviting us.

Last but not least, the EngLaId team wishes everyone a VERY HAPPY CHRISTMAS, and a wonderful start of 2013!

Red wine at Xmas

Almost there with data collecting!

Many thanks to the various people who have provided data for the Englaid project over the last month. It really feels as if we are coming to the end of the data gathering stage of the project now and can begin to work with all this information, which is quite exciting.

With a few exceptions (mainly due to changes of personnel and HER closures) we now have the HER data for the vast majority of England (see below). We are particularly grateful to Julia Wise (Buckinghamshire), Ian Scrivener-Lindley (Chichester), Gill Stroud and Nichola Manning (Derbyshire), Claire Pinder (Dorset), Pete Boland and Jennifer Mincher (Dudley), Alison Bennett (Essex), Andrew Armstrong (Gloucester City), Mark Bennet (Lincolnshire), Susan Lisk, (Oxfordshire), Alison Yardy and Richard Hoggett (Norfolk), Chris Addison (Northamptonshire), Ben Wallace and Caroline Rann (Solihull), Ken Crowe (Southend on Sea), Suzy Blake (Staffordshire), and Ben Wallace and Caroline Rann (Warwickshire) all of whom have sent HER data through to us over the last few weeks. Thanks, once again, to Keith Westcott at Exegesis for his continued efforts to assist HER professionals in processing the Exegesis data query.

Further thanks go to Simon Crutchley and Poppy Starkie at English Heritage who have provided additional tranches of NMP data (we now have NMP data for all but the north west and north east of England), and to Caroline Keay and Sara Larman at the National Soil Resources Institute (NSRI), Cranfield University, who have kindly provided digitised maps of the 1983 soil survey of England, which (as you’ve probably gathered from Chris Green’s recent postings) have provided plenty of food for thought!

Assembling more data, thinking through case study areas …

Over the last month, members of the Englaid team have been involved in a couple more regional HER meetings and have engaged with the broader research community at a workshop in Oxford on Landscape and Scale (more to come on this in a separate posting …).

Firstly, we would like to thank those who hosted to the south west and eastern regional HER meetings – in particular Chris Webster in Somerset and Vanessa Clarke in Bedford Borough – for having us along to these forums. We are also extremely grateful to all who attended these meetings for providing such thoughtful and constructive feedback on the project’s work so far as well as on its broader aims – your collective input is very much appreciated and as the following discussion hopefully shows we are considering your suggestions very carefully.

One outcome of our broader consultation with HER officers and the wider research community has been that we have begun to review the project’s original case studies (those set out in the original project design). The form and location of the project case studies has become a topic of considerable interest and we have now received a wealth of good suggestions as to how to reshape the case studies in order to satisfy our key aims of:

1) providing a sense of regional landscape variability across England
2) foregrounding data from under-exposed research areas
3) showcasing particularly rich combinations of data from the various sources consulted
4) linking into regional research agendas

The provisional results are illustrated below (the original case study areas are outlined in pale yellow).

The main outcome of this broader consultation is that many of those we have talked to felt that it was important for our case studies to traverse different landscape zones rather than focusing on areas defined either geographically (such as the Yorkshire Wolds) or by modern political boundaries (counties such as Suffolk or Norfolk). One particularly bold consequence of this is the new case study area which traverses the middle of England from east to west (a suggestion which came from the East Midlands regional HER meeting – thanks in particular to Ken Smith of the Peak District National Park Authority). We have also included a greater number of river valleys (for instance the Alne valley in Northumbria, the Lea Valley in Hertfordshire, and the Humber estuary), and a distinct island – the Isle of Wight – in part, to balance out a previous emphasis on upland areas. Two more interpretatively-led additions are a case study revisiting Hoskins’ Lincolnshire, rendered so evocatively in his seminal work The Making of the English Landscape, together with a strip of land traversing Hadrian’s Wall in order to explore the affects of this substantial piece of landscape architecture. It is also worth emphasising that the revised case studies are not fixed. Other than the case studies which we have already begun work on – the Dartmoor and Tamar Valley, Devon, and the Mendip Hills, Somerset – we would continue to welcome further ideas regarding the areas we have (re)defined. However from this point onwards, most revisions we make to the case study areas are likely to be exercises in fine-tuning rather than substantially reworking.

Finally, we have received another wave of datasets over the past month and would like to express a huge thanks to those involved in producing them. We are extremely grateful to Victoria Brown (Humber), Stuart Cakebread and Mel Bell (Greater London), Nick Crank (Milton Keynes), Sally Croft (Cambridgeshire) Ben Croxford (Kent), Lucie Dingwall & Melissa Seddon (Herefordshire), David Evans (S Gloucestershire), Jonathan Goodwin (Stoke), Teresa Hocking (Berkshire), Beccy Loader (Isle of Wight), Sarah Orr (W Berkshire) John Oxley (City of York), Sheena Payne-Lunn (Worcester), Colin Pendleton and Sarah Poppy (Suffolk), Rachel Salter (W Sussex), Mike Shaw (Black Country), Isobel Thompson (Hertfordshire), Liz Williams (Northumberland) and Julia Wise (Buckinghamshire) for sending through the HER datasets for these areas. Thanks, once again, to Keith Wescott at ExeGesIS for his continued support with processing the Englaid query for HBSMR-users.

The receipt of a new tranche of NMP data from English Heritage for the East Midlands region is much appreciated – we have now collated the NMP data for roughly half of England and are very much enjoying exploring its potential. One other more specific dataset we have kindly been given is Janice Kinory’s database of (mainly later prehistoric) salt-working sites, produced as part of her doctoral research. As the attendees of recent regional HER meetings have seen, we are now in a position to start interrogating in further detail the correspondence between various datasets and also their particular qualities.

A flood of data!

Many thanks to HEROs across England for their recent efforts to collate the Englaid data – we have now received data from almost half of the English HERs (see below). Particular thanks go to Graham Lee (North York Moors), Louisa Matthews (North Yorkshire), Rebecca Casa-Hatton and Sarah Botfield (Peterborough City), Rob Edwards (Cheshire), Jennifer Morrison (Tyne and Wear), (Exmoor), Stephen Coleman and Sam Mellonie (Luton & Central Bedfordshire), Vanessa Clarke (Bedford Borough), Dr Mike Hodder (Birmingham), Graham Tait (Devon and Dartmoor), Alison Bishop (Sandwell), Jason Dodds (West Yorkshire), Ingrid Peckham (Southampton), Alex Godden (Hampshire), Ian Scrivener-Lindley (Winchester), Jo Mackintosh (Cumbria), all of whom have sent through data in the last couple of weeks.

Following advice from several HER officers, the commissioning by the EngLaId team of an ExeGesIS query has, as hoped,  greatly facilitated the process of extracting the EngLaId data for HER officers using HBSMR software (at least 75% of English HERs). Regarding this, we are greatly indebted to Keith Westcott (ExeGesIS) for facilitating both the creation and application of this query. Equally, we would like to say that we appreciate doubly the efforts of non-HBSMR-using HER officers who have produced the EngLaId data without the aid of a specifically written query.

Finally, we are extremely grateful to Dave Yates who has provided us with a database of Later Bronze Age sites in southern England (as of 2003) drawn from the results of developer-funded archaeology. These data provided the basis for his 2007 volume Land, Power and Prestige.

The EngLaId IT specialists are now busy uploading all these data into the project database. Meanwhile the EngLaId researchers are really looking forward to analysing them in detail!