Two years ago, I wrote in these pages about an ambitious project to resurrect a c.1,400-year-old ghost. Our charity, the Sutton Hoo Ship’s Company, was founded in 2016 with the aim to reconstruct the celebrated 7th-century ship that was excavated at Sutton Hoo’s Anglo-Saxon burial ground in 1939 (a discovery that is now the subject of a major film on Netflix, The Dig – reviewed in CA 373). The prospect of recreating the 27m-long, clinker-built vessel and returning it to the waters of the River Deben and even the North Sea is an exciting one, but it is also an undertaking with a serious scientific purpose.
As I explained in CA 356, the initiative is being run as an experimental archaeology project in which, as far as we realistically can, we have been using contemporary tools and techniques (although building on a concrete floor, under electric lights). That initial article set out the thinking and the research that had gone into developing our design; the process began by mapping the original positions of the 7th-century ship’s rivets, each of which had been measured by Commander Hutchison, an engineer from the Science Museum who had been part of the 1939 investigation team. Now for the technical bit: since then, our researchers have created a lines drawing of the ship by digitising those rivet positions and using clever software – plus an experienced hand – to develop what a naval architect would describe as a ‘minimum reconstruction drawing’. (This stage of the project was published in the International Journal of Nautical Archaeology, see ‘Further reading’ on p.49.) This is now being used, together with a series of measurements (‘offsets’) that our shipwright has calculated from the drawing in order to ‘loft’ the ship – that is, to draw it out to full size on a series of boards, giving both head-on and side views. By interpolating each drawing, it is possible to see if the dimensions really do produce a buildable ship.
We are trying to build our replica as authentically as possible – an aim that requires a great deal of discussion, and sometimes compromise, which includes weighing up how our decisions might affect the sea trials, which we hope to begin in 2023. In some cases, we take our lead from research at other centres. For example, at the Viking Ship Museum in Roskilde, Denmark, their reconstruction-builders have started to use copper rivets instead of iron because their Viking recreations were deteriorating and falling apart. Do we have to relearn that lesson, when such a reputable shipyard has made the change? The density of copper is not far from that of iron, so even though there will be hundreds of kilograms of metal fixings in our finished ship, the trim and waterline will not be affected. And, as an added bonus, it also means that the reconstruction is less likely to fall apart halfway across the North Sea!
So where is the experimental archaeology in that? The timbers of the original Sutton Hoo ship had completely rotted away in the acidic Suffolk soil, meaning that the only parts of the vessel that remained to be recovered during the 1939 excavation were the rusty residues of thousands of rivets that had held the long-vanished planks together. Some of these rivets are now held by the National Trust at Sutton Hoo and the Sutton Hoo Society, and our partners in the Institute for Digital Archaeology (IDA) in Oxford have taken some, and are now subjecting them to a battery of tests never used before on these materials. An early finding of the way that the rivets oxidised gives us more exact dimensions of the cross-sections, length, and head, but we hope there is much more to come. Roger Michel, Director of the IDA, said recently: ‘In addition to learning more about where, when, and how the rivets were produced (and how we might produce rivets of our own using traditional materials and techniques), we may also have an unexpected opportunity to uncover some very specific data about the wood used to construct the ship.’
An experimental process
No build decision is taken lightly. At each stage, the usual process is that our in-house researcher, Joe Startin, surveys the literature on the matter in hand, writes it up with conclusions, offers it for review, and brings the issue to a meeting of interested Directors and volunteers – and, most importantly, our Master Shipwright, Tim Kirk. The fat then gets chewed several times before we make our decision – a conclusion that will have been subject to tests of affordability, authenticity, and practicality. Key questions for this latter test are: how easy is it to obtain the materials, what are the labour consequences, and what skills might be needed to work this way.
It is also key that every decision we make and everything we do in practice (including how difficult tasks are, unexpected events, impromptu improvements, serendipitous moments, and so on) should be recorded in detail, using words, video, and photographs. All components are measured, labelled, and re-measured and re-categorised as they are worked on. So, if a plank in, say, the third strake on the port side fails in some way (warping, splitting, rotting) we will know which tree it came from, where the tree was grown, when it was felled, and the dendrochronology. Admittedly, in some cases we do not know what use some of the data we are recording will be, but it is important to document as much as we can – who knows what archaeologists in the future will want to know about the reconstruction?
That is not to say that it has all been plain sailing. When do we – or how do we – realise we have an issue? In three ways. First, we have a (now quite complex) plan of the processes and actions to complete the build. Realistically, it is detailed about six months ahead (and then it gets very scanty). Second, our modeller is building a 1:5 model – upside down, using modern techniques and materials – and the aim is to keep the model development just ahead of the build process, so that we are assured, freshly, at every step, of the rightness of what we are doing. That aspect is already showing up some fascinating issues, as illustrated here by the words of Tim Kirk:
We have had concerns regarding the profile of the stem on our plans. This relates to the shallow depth of the stem outboard of the planking (below the rabbet line) which not only looks different to the archaeological photographs and the previous drawings, but may have an impact on the handling of the ship. This area – the ‘cut-water’ – plays a major part in any ship being able to ‘grip’ the water and to both turn and maintain a straight course. In completing the stem of the model, our modeller’s concerns have been reinforced due to the wide, flat face which the current layout will give to the bottom of the stem rather than the slimmer, more pointed sections as shown in Vol.1 of Bruce Mitford’s The Sutton Hoo Ship Burial [this huge, three-volume work, published in 1947, has been our Bible throughout the project!]. There are two possible ways of dealing with this in the full- size ship: build it as drawn and, if necessary, add area at a later date; or to experiment now at model scale by building a second.
If I can expand, the essence of the problem is that, as well as having less grip because of the shallow profile, the part of the keel that would hit the beach when grounding has been revealed to be the weakest part. So there is no logic to following the plans, which are based on the imperfect excavated shadow of the ship and the rivet positions, as extrapolated by experts. It appears that the ship remains may have become distorted after burial. In this sort of issue, the final decision must be left to the shipwright – so we will do a little more exploration but make a deeper, stronger stem that could be later pared back.
The third way that we have been investigating potential issues is by creating a mock-up, to full scale, of the middle section of the ship. It is 12’ long (in Anglo-Saxon measures) or about 3.5m. On the starboard side, we have planked with green oak – not riven, but sawn from an otherwise unusable log (as described below) and rivetted in copper. This has given our volunteers a good amount of practical experience, including the use of augers. On the port side, we have screwed plywood planks on to the frames, added a floor and temporary thwarts, and have had a first go at making tholes – the projections which are the ancient equivalent of rowlocks. While this construction is in no way authentic, it is an impressively large object and, as well as learning invaluable techniques in the process of creating it, we are already exploring the rowing dynamics with our hand-made 15’ ash oars. We have already found that our guess at the floor height and thwart height does not give a decent rowing position and the tholes will need modification. We need to get this right so that, in the end, rowers can take full advantage of their strength to propel this beautiful vessel down the River Deben and out to sea.
What else have we learned? A huge amount about running a project as tightly as possible but without compromise on materials and techniques. We have learned much about negotiations and working with volunteers. How to make friends with like-minded people. The ability to write a book about the distribution of oak in northern Europe and Scandinavia (if we had time). And lots about the character of green oak. While it does not pay to look a gift horse in the mouth, the oak we need has special qualities. The trees need to be generally about 150 years old and to be knot-free with a straight grain. (Intriguingly, there is no evidence that the Anglo-Saxons had wood saws of any size. The Romans did; later, the Vikings did. But known archaeological evidence suggests that the Anglo-Saxons did everything with axes.) You can usually make a judgement about that, but sometimes when we split, or rive, the oak as the Anglo-Saxons did, we get a surprise and the oak is not much use if you are trying to make straight plank-runs with it. And… we are up to our necks in experimental archaeology, which is where we wanted to be – watch this space for further updates!
Philip Leech is Chair and a Director of the Sutton Hoo Ship’s Company. For more on the project, and to follow its progress, see https://saxonship.org.
Pat Tanner, Julian Whitewright, and Joe Startin, ‘The digital reconstruction of the Sutton Hoo ship’, International Journal of Nautical Archaeology 49, 1 (March 2020).
Other papers produced by the Sutton Hoo Ship’s Company can be found at https://saxonship.org/archaeological-research/.
All images: courtesy of Philip Leech.