British

Archaeology

The voice of archaeology in Britain and beyond

Cover of British Archaeology 106

Issue 106

May / June 2009

Contents

news

Breton hoard of stone axeheads is first for UK

Flint finds point to Scotland's first people

Antiquities Scheme unearths second Roman pan

In the press

In Brief & Phase 2

features

Beneath the Sea Special: Part 1
Discovery and work on HMS Victory

Beneath the Sea Special: Part 2
Underwater landscapes and the Swash Channel wreck

THE BIG DIG: Wallingford
Community research project in this historic Oxfordshire town, said to have been founded by King Alfred

The Nighthawing Report
While most metal detectorists give positive contributions to the archaological world, nobody is perfect. Pete Wilson considers tackling the rogues

spoilheap

Proud of all humanity – and Homophobic (Latin or Greek?)

on the web

Recommended websites
Discovering historic landscapes, and a major Gallo-Belgic pottery resource

letters

your views and responses

CBA Correspondent

Gill Chitty introduces some recent examples from the CBA's advocacy files

 

ISSN 1357-4442

Editor Mike Pitts

features

Beneath the sea

Underwater landscapes

Think of maritime heritage, think of shipwrecks: but Caroline Wickham-Jones says there is much more to the history that surrounds our shores, and understanding and protecting it are major challenges.

If you travel round the coasts of Europe you will hear tales of sunken cities, and of bells that toll underwater as the sun sets. There is a different story in Orkney. Divers there talk of a mysterious submerged structure uncannily like a prehistoric chambered tomb. Some claim to have entered it, and there are rumours of creel men bottoming their boats at low tide.

Perhaps this is just a reflection of the prevailing local culture – every region has its Atlantis myth, and in Orkney the neolithic stone circles, tombs and houses figure strongly in local identity. But could it be true?

If we go back some 12,000 years to the end of the last glaciation, Britain was a peninsula of north-west Europe. Lower relative sea-levels in many places meant that the look of the land was quite different. This is due to a phenomenon known as differential crustal rebound. Put simply, land is not rigid. The nearer to the maximum depth of ice, the more it got pushed down during the ice age. As the ice melted, so the land started to rebound, but because the weight of ice varied greatly across the country, so did the movement.

At the same time, the waters released from the ice entered the sea to increase its volume. The net effect of differential crustal rebound means that in some places, such as the west coast of Scotland around Oban, the sea at the end of the last ice age lay higher than today, forming prominent raised beaches. In others, such as Orkney, areas now underwater were dry. Since then a complex rebalancing between sea level and land has exposed terrain around Oban, while considerable tracts have been submerged around Orkney.

Drowned prehistoric sites have been acknowledged before. In 1893 Walter Traill Dennison recognised the evidence that once-forested parts of Orkney had become submerged. In 1913 geologist Clement Reid published Submerged Forests, in which he argued that around Britain "the antiquary" ought to find "no complications from rifled tombs", and "implements of wood, basketwork, or objects in leather, such as are so rarely preserved in deposits above the water-level".

Only recently, however, has work taken off through a happy combination of funding, such as the aggregates levy for England, and technology. Hightech computer analysis such as that of Vince Gaffney and his colleagues at the VISTA Centre in the University of Birmingham, has combined with developments in remote sensing and recognition, such as those employed by Wessex Archaeology in their Seabed Prehistory Project, to provide a wealth of information. This is assisted by close collaboration with our colleagues in geosciences – in order to understand just how much the topography around the coasts of Britain has changed it is necessary to understand the geophysical processes which have driven that change. This is not only a case of looking at ice cover and elasticity of the land; we need to use a whole suite of techniques to visualise these earlier landscapes.

The seabed is in demand today, however, and this means that there is plenty of relevant data, though it is not always easy to analyse and sometimes has to be hunted out. Mapping Doggerland, by Vince Gaffney, Ken Thomson and Simon Fitch (Archaeopress 2008), shows just how esoteric the information and how bizarre some of the archaeological partnerships can appear at first: the project began with a call from an archaeologist to a commercial survey company explaining that "All we need is several million dollars worth of your 3D seismic data!"

Research is still in its infancy, and it is hard to quantify the whereabouts of archaeological potential. But the potential is there. Back in the palaeolithic large tracts of now submerged land, particularly to the south and east, were available for settlement (Doggerland, now under the North Sea). A glance at the abundant seabed finds from other countries, such as the Netherlands, indicates what could be recovered. Chance artefacts, such as the small flint scraper taken from an oil core between Norway and Shetland in 1986, or the 28 handaxes dredged from the southern North Sea (News, May/Jun 2008), confirm the existence of material in British waters. More recent evidence may survive according to the complex sea level history of an area. Dating any submerged land surface is specialist work, and many finds are still subject to the relative dates suggested by modelling – in itself an inaccurate science.

Funding problems mean that existing projects are mostly small scale and sporadic, not a good way to build a database, especially one to be used for management. Work in Orkney, Scilly and the Solent (News, Jan/Feb 2009) has demonstrated the possibility of archaeology from periods such as the Mesolithic and Neolithic (10,000–2200BC). In Orkney sediment dates suggest that sea level reached present levels only around 2500BC, opening the possibility of a submerged prehistoric landscape to rival well-known sites such as Skara Brae or the Ring of Brodgar. Of course not everything survives submergence, and the mechanics of preservation are complex, but work in countries such as Denmark demonstrates that the greatest potential lies in island groups such as these.

Where sites do survive underwater it is worth noting that preservation levels are often high, yielding unusual detail to add colour to our interpretations of prehistoric life. Submerged landscapes and sites are not, therefore, simply a management problem. We ignore a valuable part of the resource. We are loosing academic information and we are loosing the potential for public interpretation.

The enthusiasm and work of a dedicated band of specialists means that Doggerland is, in general, well known. But it is one thing to study an area, and quite another to manage it. Increasing demands on the seabed from activities such as energy installation, aquaculture and dredging mean that submerged cultural remains are under threat. Heritage bodies are well aware of this. English Heritage's historic seascapes programme provides historic and archaeological management information based on characterisation of the seabed, but it has yet to reach beyond England, or, it seems, have much influence on Natural England's current undersea landscapes campaign.

The study of wrecks and other maritime remains has made us, as a nation, culturally aware of our waterlogged resources, and submerged dry-land sites have been able to piggyback on the back of this. Historic remains are thus covered, at least in principle, by the marine and coastal access bill, which broadly covers England, Wales and aspects of related matters in Northern Ireland, and the marine bill (Scotland) – both currently going through their respective governments (see other feature).

However, it is worth reflecting that even when the first Ancient Monuments Protection Act was passed in 1882, Britain had a respectable history of archaeological and antiquarian research to provide basic information on the resource. By the time of its most recent incarnation in 1979, as the Ancient Monuments and Archaeological Areas Act, there was an extensive site database. With regard to submerged cultural sites and landscapes, we are by comparison in the dark. Although some sites have been recorded, they are few and not geographically or chronologically representative. Despite numerous protocols and guidelines, and even nascent marine bills, it is hard to see how we will succeed in managing a resource we know so little about.

A common feature of all the existing legislation is that it appears to have been driven by the demands of maritime archaeology, in particular of shipwreck sites. Submerged sites and landscapes are certainly covered, but the current documentation reads as if they were an afterthought, undoubtedly reflecting the expertise and interests of most of those with responsibility for the underwater heritage. It could be a dangerous weakness. Wreck sites are important, but current research has highlighted the potential and fragility of drowned landscapes, ruins and sites around our coasts. The identification, understanding and preservation of these sites require a different suite of, albeit related, skills and interests.

If we are truly concerned with the wellbeing of our marine heritage, we need to give submerged sites and landscapes equal status, likelihood and interest as wrecks. At the moment a marine environmental impact assessment in UK waters can claim to have covered the archaeological record with a wreck search. As one involved with submerged archaeology, I am questioned in detail about propellers, spars, or sheets of aluminium, but not the much older landscape changes or submerged prehistory. It is a matter of awareness; we are only just beginning to explore all that the submerged world has to offer us, something that this sort of train-spotting mentality will not protect.

Underwater cultural heritage is also covered by international legislation. The Valetta Convention (1992), the United Nations Convention on the Law of the Sea (1994) and the UNESCO Convention on the Protection of the Underwater Cultural Heritage (2009) all address aspects. As yet the UK has still to validate the latter convention, and yet again it could be argued that the driving forces reflect the abundance and visibility, and potential value, of wreck sites.

In Britain, the UK and Scottish marine bills do acknowledge a wide variety of cultural remains. The issue of landscapes and sites, however, is still by and large theoretical: these bills are designed to protect a resource that is not understood. This is going to be difficult. In England, work by English Heritage and others has started to highlight the potential. In Scotland such work has still to take place.

The impact of the bills is significant, however, in that they provide the opportunity for truly integrated conservation. The UK bill incorporates measures to set up a marine management organisation (MMO); in Scotland, Marine Scotland will take on the role. The precise remits of these bodies have yet to be clarified, but it is vital that they incorporate archaeological expertise and the ability to manage the protection of submerged cultural heritage in-house.

On land, archaeological sites are too often the poor relation of birds, peatland drainage and flora where planning applications are concerned. This is hardly surprising when they are championed apart, by their own, separate, body. Yet the people of the past lived in the natural world. The divide between human and nature does not make sense if we are to understand and manage our archaeology properly, below the sea as much as above water. The success of organisations that incorporate archaeological expertise should point the way forward. It is to be hoped that the opportunity to set up effective management of the underwater heritage wherever it occurs in UK waters will not be lost.

It is good that we are taking cognisance of the underwater world. But we have a long way to go before we can fully understand it, never mind protect it, whether wreck or tomb. And to return to those Orcadian myths, we are looking for that tomb. There is more to the seabed than most of us realise.

Caroline Wickham-Jones is a lecturer at the University of Aberdeen, co-editor with Karen Hardy of the SAIR Scotland's First Settlers project and co-director with Sue Dawson (University of Dundee) of The Rising Tide, a project to investigate former sea level change and the early settlement of Orkney.


The wreck in the Swash Channel

An important 17th century shipwreck off the Dorset coast has been under observation for five years. As Dave Parham and Paola Palma explain, its legal protection cannot slow its rapid natural degradation. Can it be saved?

In March 1990 the Dutch dredger Scaldis hit an obstruction whilst undertaking maintenance dredging close to Buoy No 3 in the Swash Channel, part of the approaches to Poole Harbour in Dorset. Substantial timbers and a single iron cannon were brought to the surface. Having used a grinder to clean up the gun, the crew reported the finds and the cannon ended up in Poole Museum store. Maritime archaeological activity in Poole at the time was focused on the Studland Bay wreck, a late 15th/early 16th century site located around 500m from Buoy No 3. The new find was forgotten in the struggle to keep the Studland project on track.

In 2004 more dredging was planned for the Swash Channel to allow large, cross-channel ferries into Poole. Poole Harbour Commissioners required an environmental impact assessment for such a capital dredging scheme, the archaeological component of which was undertaken by Wessex Archaeology. The 1990 cannon find forgotten, a geophysical survey was undertaken of the channel which revealed, amongst other things, a large, perhaps 20m long, anomaly with smaller outlying features close to Buoy No 3.

A dive on the site revealed the remains of a large, wooden shipwreck and some initial investigations suggested that it was of late 16th/early 17th date. Typically the site was reported to be the wreck of the Spanish Armada vessel San Salvador, lost in the area in 1588 – the immediate candidate whenever a wooden wreck is found anywhere near Poole. Under the Protection of Wrecks Act 1973, it was designated on December 10 2004, when heritage minister Andrew McIntosh said:

This is an important wreck… it is likely to be well preserved and rare in terms of its quality and the quantity of the surviving structure… This order is particularly timely as the location of the wreck has been publicised and we need to protect it from potential damage by divers visiting the site.

Wessex Archaeology undertook a designated site assessment for English Heritage, recording a zone of structure some 20m in length and reporting that further remains were known to exist in the area. The structure included parts of the ship's forecastle, complete with galley and gunports, an extremely rare survival as ships' upper works are usually destroyed during the wrecking. Importantly the structure showed signs of being recently exposed, and after a short time it was seen to be degrading. Further work undertaken by Wessex involved the temporary protection of part of the site by sand bagging in advance of the dredging work, and the recovery of small concretions seen on the surface.

With the site characterised and shielded from dredging, there was an urgent need to establish the character of sediment movement and biological attack. English Heritage and Poole Harbour Commissioners approached Bournemouth University to monitor the level of physical and biological degradation. This was to be undertaken by a combination of university staff specialist skills, research use of its extensive laboratory base and the incorporation of work on site into a taught unit on Bournemouth's marine archaeology programme. The combination of management funding, staff expertise and student involvement, achieved management, research and educational aims beyond the sum of the parts. Since 2006 the bulk of the work on site has been undertaken by Bournemouth students acting under staff supervision.

In May 2006 we located the site and discovered that the protective hessian sandbags had degraded, and the wreck was once again exposed. In addition, new structure could be seen: the site was considerably more extensive than first thought, covering an area of some 50m×40m with extensive structural remains over 40m×20m. It was evident that much more work than was originally anticipated was required. With no further funding available, Bournemouth University negotiated sponsorship with a number of local organisations in attempt to encompass this extra work.

Scientific monitoring showed extensive evidence of physical, chemical and biological degradation of the archaeological material. As more of the ship's hull is exposed it is subject to severe attack by shipworm (a marine bivalve mollusc notorious for boring into and destroying wooden structures). Also discovered on site was Lyrodus pedicellatus, a rapidly destructive, warm water shipworm. Increases in UK sea temperatures due to global warming have allowed this native of southern waters to thrive here. The species had already been identified on the Mary Rose site by Palma: it would appear that this borer is quickly spreading along Britain's southern coasts.

Because of the clear evidence of rapid degradation in 2007, English Heritage commissioned and partfunded a trial using the Swash site as a case study for establishing the most cost effective method of in situ stabilisation. Different strategies were deployed over a 12 month period. Rather than just focus on sacrificial samples which could offer limited results, the innovative methodology involved study of the timber decay of the original hull and the efficiency of different protective methods.

We also showed that new exposure of the ship's structure was proceeding faster than it could be recorded, and during 2008 English Heritage funding made possible a complete photographic resurvey of the entire site, allowing, for the first time, a full understanding of its distribution. By the autumn sediment monitoring had shown lowering sand levels across the site, by up to 350mm in some areas. The gradual exposure of new material has reached the point where extensive archaeological deposits that contain extremely vulnerable organic material are being exposed, rapidly degraded and eventually lost.

The main threat to the site is not the rogue divers referred to by the minster, but the natural environment, which traditionally pays little respect to acts of parliament. Initially it was agreed with English Heritage that no material would be raised. However, as experience quickly showed that leaving exposed material in situ results in its degradation or loss, an agreement was reached with English Heritage and Poole Museum, the receiving museum for the site, whereby material is recorded in situ and recovered if deemed to be at risk.

Items raised to date include silver spoons, pottery, butchered cattle bone, a copper alloy hand bell, a copper alloy skillet, a wooden carving of a merman, leather shoes, lead shot, rigging elements and a wooden tool handle and a gun carriage. Material known to exist on site (in addition to ship's structure) includes an 8m long rudder with a carved human face at its head, a further small carving, seven iron guns, three barrels, numerous elements of rigging including block (with running rigging still rove through them) and standing rigging, cannon balls, ballast, the remains of a galley and possible pump elements. The material currently left in situ is temporarily protected to one degree or another: but work since 2006 has demonstrated that the site lies within an eroding seabed, and that each year more of the wreck is exposed and rapidly decays.

Research is at an early stage and has yet to provide an historic reference for the loss, but the significance of the site can perhaps be examined by one single aspect of the project. Rudders are only in place on a small number of historic wrecks in the British Isles: the rudder of the Mary Rose (1545), missing its upper portion; that of the Spanish Armada-requisitioned merchantman La Juliana at Streedagh Strand in Eire (1588); that on the Alderney Elizabethan wreck site (c 1590), which is missing its lower portion; and that of the Royal Navy brig HMS Primrose (1809), which is incomplete. Carvings are even less usual, being known only from the wrecks of HMS Colossus (1798) and the Duarte Point wreck site (1653).

The dates would suggest that the ship carvings from the Swash are the earliest such examples in the UK, and amongst the earliest in the world. On none of the other UK sites are these two features (ie a carved rudder) combined. The only parallel that has been discovered to date is that of the rudder of the Swedish warship Vasa, which has a carving attached to the rudderhead. At c 10m this is somewhat longer than the Swash Channel rudder, but is superficially similar in form. Describing a rudder, Mainwaring's Seaman's Dictionary of 1622 mentions four, five or six pintles (the iron strapping and pins that connect to the hull), presumably depending on a ship's size. On this basis, with six pintles the Swash feature is from one of the larger ships of her day, confirmed by using the rudder's length to estimate the vessel's size.

The limited archaeological evidence points to a relatively high status armed ship lost in the first quarter of the 17th century, perhaps around 1620. The small number of guns and the position of the galley, in the forecastle rather than the hold, suggest a merchantman rather than a warship. Research also shows that the site is naturally eroded and degrading at an alarming rate. So perhaps the most important question is what happens next? Work to date has been funded by a combination of bodies with sponsorship from local marine industry. However, the scale of the problem is such that this ad hoc arrangement can no longer match the problem, and discussions are underway with English Heritage to find a more permanent future for the site.

Dave Parham is senior lecturer and Paola Palma is lecturer, both in marine archaeology at Bournemouth University. An event was held at the University on 2 May to meet the authors and see artefacts from the wreck.

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