Conclusions

In the articles on the construction of Tilia, we have covered many different aspects of the reconstruction of the Hjortspring boat. The conclusions of the results of the work partly cross-cut the division here.

Dividing the work into groups that dealt with different topics proved to favour the work and its quality in many ways. First and foremost, it helped attract people with specific interests that they could nurture and develop in an interesting context. A sense of belonging was formed between group members, which developed into a comradely community. As most active members were members of several groups, a network of contacts was formed across the guild. This was important not only for group work, but also for solving major tasks that went beyond the scope of individual groups. The main governing unit was the monthly meetings, where each group was expected to report to all those who attended.
The purpose of the monthly meetings was to give all members present an impression of the project as a whole, an impression that could influence the choice of solutions in each group. An atmosphere was created where everyone talked about everything, commented on the reports and felt at home among equals, no matter how different we were.
The somewhat formal organisational chart was put on the overhead projector at each meeting, which kept the integrity of the project intact.
The group division, the monthly meetings and the continuous use of the organisation chart contributed significantly to the quality of the work.

The choice of ongoing documentation in the form of photos, videos and reports for the member folder has proven to be the right one. It wasn't just a boat we were building, it was a body of knowledge we were generating in the form of the boat. The member folder came to contain all the final conclusions and choices, often in sketch form.
The contact with museums and educational institutions that had been established was favourable. Our method of sending each member of our ‘scientific network’ a membership folder and then regularly sending them our reports made it more legitimate to disturb individual museum employees when we were in doubt about solutions.

The financial management of the project and guild is working satisfactorily. The accounts and budget are divided into two: The building accounts and the guild accounts. The latter is financed by the membership fee, which has remained unchanged for all years. (100 kr./year). The money in the guild fund is used to send out reports and for administration. No funds are sought for this. A spirit has developed whereby small amounts, mileage, tractor loans, etc. are paid by the member involved in the matter. Our overheads have been very modest.
The construction accounts include everything related to the building of the boat and projects related to the interior design of the Linde Shipyard. It was financed primarily by foundations and secondarily by own income. The division into a guild and a building account meant that we could in good conscience inform foundations and visitors that their contributions went entirely to the purpose (and not to club activities).

It can be concluded that the organisational method worked well and was conducive to the purpose. It worked even though the guild members are very diverse in terms of background, personality and interest. Very few have left because they were offended by the working method or the prevailing ‘good-natured cordiality’.

The boat building was primarily based on Rosenberg's description of the find, Johannessen's drawings and the findings from the National Museum's latest installation of the boat. However, during the course of the work, deviations or additions were made that, after much scrutiny, were deemed to be more accurate.
One significant deviation from Johannessen's interpretation is the increased sheer we had to give the boat in order for our logs to contain the railing planks. It is also unlikely that in the Iron Age there were linden tree trunks with a diameter as large as 1.35 metres at a height of 10 metres, let alone curved trunks.
Another anomaly was the use of the tension rope. We haven't proven that it was necessary, but intuitively we feel that it strengthens the boat considerably and prevents keel cracking.
Landing the side and railing planks outside the stem pieces instead of inside, as Johannessen had suggested, worked well and without problems. The use of ‘rigging screws’ to hold the topsides down was a necessary measure.
Choosing bast as a lashing material instead of birch roots is not necessarily the right choice. All we can say is that the bast cords have been strong enough. Not one has broken or become loose in the binding during the four years of sailing.
The sealing material, wool cords saturated with cowhide and linseed oil, has worked reasonably well. We think that resin would have provided a more slip-resistant joint.

The Hjortspring boat is highly refined in all its details. For example, the optimisation of the strength-to-weight ratio shows that the boat must have been one in a series of increasingly elegant designs, with knowledge passed down from man to man. It must have been built in a shipyard by professional boat builders. This is not a ‘do-it-yourself’ boat.
No practical use has been found for the horns, so it must be concluded that these are to be regarded as decorations that perhaps carry the designs of the past. The spires of Roskilde Cathedral do not have any real function either. Over longer distances and in moderate seas, the boat can sail at a speed of 4.5 knots, its range in calm weather would have been up to 40-50 nautical miles per day. Over a short distance, the boat can reach a speed of 8 knots.
The Hjortspring boat has a high load capacity. With its own weight of 500 kg, it can carry a load of 1,000 kg in addition to the crew, a total load that is five times its own weight. It is described as a war canoe, but it could just as well be called an armoured coastal boat that, with a powerful engine (20 paddlers), could transport one tonne of cargo over long distances at an acceptable speed.
The boat is highly manoeuvrable. A turning diameter at speed of 30-40 metres is excellent for such a long boat. The braking distance in heavy shunting is less than a boat length.
Directional stability is poor, so a steering stretcher is necessary.
Stability is poor. It is especially felt when the boat is boarding. During sailing, the instability is not felt, so ballast has hardly been used.
There is no indication that the boat carried a mast and sail. The general opinion among archaeologists is that sails first arrived in the Nordic countries in the 5-600s AD.
With the wind on the windward side, you might want to put a cape between a pair of spear poles.

Only a few rock carvings have hints of masts. Here we show a pair from Horsahallen in Möckleryd near Torhamn, the south-eastern corner of Blekinge.
The curved keel and railing lines show that the carving is from the Late Bronze Age or Early Iron Age.

Linden wood is an easy material to work with, a wood carving material that is used for altarpieces, among other things. After trials, the cutting angle of the axes and steels was chosen to be as low as 15 degrees.
Broad axes were used very little, as the cutting direction was mainly across the grain. Here, the ‘Mästermyr’ cross-cut axes worked excellently, even when cutting curved planks. However, the so-called ‘Hjortspring iron’ became the preferred tool. It was shanked as a chisel instead of a crosscut axe. The choice of chiselling as a chisel rather than a cross-axe certainly had to do with our limited skills. There is little doubt that if we had mastered the chopping technique, the production of the planks would have been faster.
The demand for tools fuelled the blacksmith group, which quickly attracted several interested members.
Beating the lime bast cords followed ‘modern’ methods. Bast cords were now also made entirely by hand. The result of this production was neither worse nor better than with the ‘machine’ method.
When sewing the plank joints, or rather when tightening them, we initially used a copy of the S-shaped wooden tool that was part of the find. It worked very well and can therefore be considered a tool that belonged to the boat's equipment.

It took two years from the time we had secured a place to build the boat until the big logs arrived. This was fortunate in a way, as we were almost forced to do some preparatory work. We learnt how to handle Iron Age tools, we got the properties of linden wood into our blood, and we studied and chose the design of the construction details.
At the same time, the construction crew was imperceptibly divided according to skills and interests into different tasks such as rough chopping, finishing, tool sharpening and cleaning up. The latter was especially important, as a tidy, organised workshop immediately resulted in higher quality and greater personal safety. After having three axe blows to the legs, we wrote a safety guide and since then we have largely avoided accidents.
Making replicas of the find's wooden parts, such as shields and turned canisters as practice pieces gave a boost to the group that handled the historical part of the project.
The production of the two test pieces convinced ourselves and those around us that we had a realistic project on our hands, while the construction group resolved several unresolved questions regarding the assembly.

Even though we had got a good grasp of the boat's many details during the exercises, several new problems emerged during the actual boat building. One major difficulty lay in the quality of the logs. The loose cores in the logs and subsequent gluing was a lot of extra work. Stretching the bottom plank using fire was a likely method in ancient times. We just didn't dare.
The clamping of the keel and then the stem and planks was a particularly important task that was successfully completed. The boat lay perfectly straight in the water.
Our logbook shows that we spent 10,000 man-hours building the boat. 2,000 of these hours were spent on coffee breaks, where the topic of discussion was often small detail problems. A lot of time was also spent talking about the design during the actual work. We estimate that a total of 3,000 hours were spent because we had never built a boat like this before, unlike our predecessors.
The gluing, or rather especially the preparation of it, swallowed another 1,000 hours.
Another time-consuming factor was that we had to build an exact replica of the found boat. Our predecessors probably adapted their boats to some extent to the trees they had available.
If we had built a new boat right after launching Tilia from sufficiently large and healthy trees, it would probably have taken around 5,000 man-hours.
We estimate that our predecessors, who, as we claim, worked in a shipyard, would have spent 3-4,000 man-hours. That's the equivalent of ten men for a couple of months. The biggest problem must have been transporting the logs to the shipyard.
The boat was convincingly elegantly built. Every detail had been taken care of. They were professionals, the boat builders of the time.

The history group aimed to answer the questions:

Where did they come from?
Who were they?
Why did they come?
Who did they meet?
What happened to them?

It was an ambitious goal, and the questions were not convincingly answered. The interpretation of the various artefacts and the boat's sailing characteristics point in very different directions.
The boat could have come from far away. It is Scandinavian in its construction. The swords are of East Germanic design. The turned wooden boxes and chain mail point to Celtic culture. The shape of the spearheads points to the Swedish east coast. The jar points to the Jasdorf culture near Hanover. The shields have a Celtic shape, but may also be a widespread fashion in Scandinavia.
The many directions that the parts of the find point to could well emphasise that there was widespread trade and exchange of goods and gifts in the Northern European region. If this statement is correct, only a few characteristic parts of the find can be used as a ‘Leitmotif’, namely the boat, the turned cans and the chain mail. The iron weapons may have come from the Celtic area or from the German/Polish Baltic coast. It was realised that the crucial prerequisite for a credible answer to the question: ‘What happened?’ is knowledge of the population density on Als in the Celtic (Pre-Roman) Iron Age.
Assuming that several thousand people lived on Als at the time and that there was a societal structure with a chieftain and a hird, we can support the hypothesis that there was an actual battle between the established Alsatian society and an army that invaded Als in several boats. (Kaul, Fl., Randsborg, K., Rieck, Fl.).
Whether we assume that there were 3-4,000 or only 3-400 people living on Als at the time, another hypothesis is also possible:
A group of merchants or emissaries from the Celtic area in southern Germany travelled in their riverboat down the Oder to the coast of the Baltic Sea. Here they chartered a coastal boat of Nordic origin with crew. The purpose was to head north along the east coast of Jutland to introduce the latest weapons technology, sell these weapons or use them as gifts to establish a sense of belonging. The turned bowls and cans have been samples.
Along the way, they have had to dock at the Alsatian coast for the night or due to bad weather. The boat may have had a leak. The natives, the Alsatians, discovered their campfire on the beach, attacked them with their longbows and killed them. Naturally, the Alsatians did not want their neighbours in Jutland to rearm.
According to tradition, weapons and equipment had to be given to the gods by immersion in the holy lake.
Perhaps a Hjortspring boat with other Celtic goods, such as the Gundestrup vessel, successfully crossed Alssund and Alsfjord at another time.
The Dejgbjerg wagons could also have been cargo on board a Hjortspring boat when disassembled.
Sailing was once the easiest method of transport.

Imagination has no limits, other than those derived from concrete knowledge.

Hvad Haanden former er Aandens Spor.