«Introduction The VIAS – Vienna Institute for Archaeological Science – is an interdisciplinary research unit of the University of Vienna. For the ...»
PUTTING WOODWORKING TOOLS OF
THE MIDDLE BRONZE AGE TO THE TEST
Building a gateway at the Terramare settlement in Montale, Italy
by Wolfgang F. A. Lobisser, Wien
The VIAS – Vienna Institute for Archaeological Science – is an interdisciplinary
research unit of the University of Vienna. For the past 20 years employees of the
experimental archaeological working group of the VIAS have been dealing with the evaluation of archaeological findings, implementation of prehistoric archi- tecture models and the study of prehistoric craft techniques connected to that.
The aim of our work has always been to recreate wooden buildings or other structures of the past based on individual archaeological findings with the techno- logical means and materials of the era in terms of experimental archaeology. So far all steps were carried out by using original techniques so that it was possible for us to integrate the data obtained to get concrete ideas of the technological possibilities the people of the past had but also to better assess the total effort in- volved for each project. In addition, modern tools were partly used, whereby we took care to ensure that visitors were only presented with evidence of authentic working methods from the respective eras in the finished architectural models.
To undertake large-scale empirical studies on wooden architecture, it was essential to find project partners, who in turn had an interest in such construction projects and could also provide funding. In the course of different open-air contracted research projects, in recent years employees of the VIAS have been engaged not only in practical studies on wooden architecture of the Stone, Bronze and Iron Age, but also in projects of the Roman Empire and the Early Middle Ages and have in total erected about 50 individual buildings. The result of these ventures was a classic win-win si- tuation: For archaeological research it provided the opportunity to carry out experi- mental studies on a large scale. The project partners received architectural models that were built according to the current level of research and which in conjunction with archaeological exhibitions, could be marketed for sustainable tourism purposes in archaeological open-air museums. It thereby was possible to make history visible to the public and to enable the vicitors to experience it by feeling and touching.
An archaeological open-air museum of the Terramara in Montale In conjunction with the EU project ArchaeoLive and based on results from local ex- cavations, an archaeological open-air museum of the Terramara Culture was con- structed in 2000 in Montale, a small town south of Modena under the guidance of 103 Dr. A. Cardarelli from the Museo Civico Archeologico Etnologico in Modena (BARTH et al. 2003; CARDARELLI u. PULINI 2004).Additional partners of this EU project were the Natural History Museum Vienna, where, under the direction of Dr. F. E. Barth at the Salzberg in Hallstatt reconstructions of Bronze Age buildings were erected (BARTH u. LOBISSER 2002), as well as the Pfahlbau Museum Unteruhldingen, where under the direction of Dr. G. Schöbel at Lake Constance, similar activities took place (SCHÖBEL 2005).
The Terramara refers to a cultural phenomenon in the region of the lower plains of the river Po in northern Italy, where between 1650 and 1170 B. C. almost quadrangular fortified settlements with inner areas usually in excess of 10.000 m² were built (cf. Brea, Cardarelli and Cremaschi 1997). These settlements were mostly protected by wood and earth defences with ditches and inside the villages following a regular perpendicular layout were rows of houses and streets. Special entrance systems with earthen or wooden bridges allowed access to the settlements.
In 2006, the experimental group of VIAS was invited to construct a portion of the fortification with an entrance as a new architectural model using experimental archaeological methods at the open-air museum of Montale (Lobisser 2008).
In Montale, the traces of a Middle Bronze Age terramare settlement were detected with external dimensions of about 100 m to 120 m. The ditches of the fortified settlement were clearly visible in the ground and showed rounded corners and within the walls there was evidence of house remains. There were also partial wooden structural elements preserved which give an indication of the building structure of the houses (cf. BERNABO BREA et al. 1997). In several settlements from around the same period, such as the Terramara di la Braglia or the Coppa Nevigata in Puglia, we are familiar with archaeological findings, which show that the entrances to the settlements may have been 3 to 4 m wide and up to 9 m long (see BERNABO BREA et al. 1997). One discovery from the 19th century at the Terramara di Castione Marchesi (PIGORINI 1883) allowed valuable conclusions to be made for the design of the fortified wooden constructions. It shows wooden cages in block design lined up so that the protuberances of the cages in turn formed their own compartments lengthways. The internal dimensions of the individual cages measured about 3 by 3 m and there were also several indications of associated tower-like structures.
In close cooperation with the Italian colleagues, as well as local architects and building experts, a blue print was drawn up for our reconstruction project in Montale for four wooden cages to form an entrance about 3 m wide and 9 m long leading into the interior of the settlement (Ill. 1). The gate itself was designed as a turnstile construction with two panels and positioned approximately in the middle of the entrance. It is closed at the top with a bridge and same as the cages has a palisade.
104 Fig. 1: The floor plan for our reconstruction was developed based on findings from several excavations of fortified settlements from the Middle Bronze Age Terramareculture; by A. Cardarelli.
With the practical work in Montale, it was our goal to gain a better understanding of the technical capabilities of woodworking of the Terramara. From the outset of the project there were many questions: How do we envisage the construction of a fortification from the Middle Bronze Age? How many working hours were required? How much building material was needed? Which wood joining techniques were available to the people of the Bronze Age? How resilient were bronze tools when working on solid oak trunks? What types of tools were particularly suitable for certain types of work? During the course of the work a number of questions arose especially with regards to the wooden shafts of the axe blades, which are elaborated in more detail later. We wanted to avoid using modern resources such as cranes or hoists and bring all the design elements in position by hand with the aid of levers, pulleys, and inclined planes.
For our experimental studies on wooden crafts in the Middle Bronze Age in Montale, we made tools of bronze based on archaeological originals. We made large and small flanged axes, chisels of different sizes, bronze daggers, bodkins and awls as well as wooden dividers with bronze tips. There were also a number of tools made of wood such as cleavers, mallets, levers and reels to be able to transport the poles. The large flanged axes weighed about 425 grams. The handles were made of angular grown beech and ash woods; the handle itself came from the trunk and the tool arm from the wooden knot. To attach the blades to this knotted part, they were equipped with a narrow chisel with slots in which the blades could be inserted so that the cutting edges were parallel to the handle. These connections between splice and metal blades were additionally secured by twine lashings. Some of the small blades which weighed around 125 grams were also equipped with handles in this way.
If we look at the development of woodworking from the very beginning of the Neolithic, we notice that adzes have played an important role from the beginning (LOBISSER 2013). Our practical experience of recent years has shown that adzes with their cutting edge hafted crossways to the handle are excellently suited to working on structural timbers of all kinds. In the late Neolithic period, we find a whole range of adze blades in different sizes, which differ significantly in shape from the axe blades. We only know bronze tools described as “axe blades” from the Early and Middle Bronze Age in comparison. If we assume that such an important type of tool type wasn’t simply forgotten at the beginning of the Bronze Age, we must ask ourselves the question: Where are the adzes of the Bronze Age? In the course of our work we wanted to find out if it was possible that we could not find these adzes because the metal blades do not differ from the axe blades. Based on that, we hafted some of the smaller flanged axes in a way that their cutting edges were crossways to the wooden handles to test their functionality as adzes.
Some chisels of the Terramara were noticeable by their particular size. With lengths of 25 cm or more and weighing around 300 grams, they indicate that grooves, slots and cut outs of considerable dimensions belonged to a common spectrum of wooden connections. Working from two sides, you could theoretically cut out rectangular holes from one side to the other in poles up to 40 cm thick. We wanted to use awls and bodkins as well as bronze tipped wooden dividers for marking wooden joints. Dagger blades were probably multifunctional tools and could have very varied uses in woodworking such as for carving wooden nails.
106 The construction work in practice
To get an idea of how they might have felled trees in the Middle Bronze Age, we conducted several experiments with our larger axes. We learned that oak timbers of 30 cm in diameter could be felled in just under an hour using our flanged bronze axes. In most cases we were able to make the trees fall in the desired directions by chopping notch cuts and felling cuts into the upright timbers about 60 to 70 cm over the floor level. It was important that the felling cut was slightly higher than the notch cut that would determine the direction a tree would fall. To remove the bark from the oak timbers, we successfully carried out this task using bronze axes, where the hafted angular handles provided a good grip as we could use them as a lever. One attempt to haft an axe blade on to a long straight wooden handle in order to use it as a large slick was not satisfactory because the narrow curved blade at the front slipped sideways repeatedly.
At the construction site, the first four poles were then cut to the right length with axes and positioned, whereby the first two were placed on the ground approximately 3 m apart and the other two placed at right angles on top of the first pair. Since the structure was built out in the open air, we cut out semi-circular notches at the corners of the wooden cages in the top poles, so that rain water could drain off rather than being collected in the hollowed notches and speed up the weathering process. In order to achieve perfectly fitting joints, the poles were individually customized and we used our bronze tipped wooden dividers for this. When a pole was precisely positioned, the length by which it would need to be lowered was marked with the dividers at both contact points, so that the cuts were exactly equal to the diameter of the two underlying poles (Ill. 2). Then the pole was rolled inwards and turned 180 degrees so that we could cut out the two grooves. After some practice, we managed this task very well using the large bronze axes.
Some issues arose after a while during this work because the twine lashings that connected the bronze blades and wooden shafts were affected by the sharp edges that formed at the edge of the notches of the poles.
The tight lashings became loose or came off completely, so that the axe blades were not fixed strongly enough in the hafted slots. A significant improvement could be achieved concerning the lashings by leaving a thicker sections in the wood at the forked ends of the hafted joints, to prevent the lashings from slipping down on the one hand and provide some protection Fig. 2: Withtransfer the different wooden dividers it was our bronze tipped possible to diameters of the indivion the other. We have since found dual logs exactly on to the following one, so that a close a preserved hafted angular handle joint was ensured (Photo: W. F. A. Lobisser).
108 We found out the limits of the bronze tools working on the tree knots, which left big nicks in the blades or even bent them. The rule was to avoid these as much as possible. It was actually not a big problem to straighten bent blades again. We had cold forged our blades several times over already anyway before starting work to increase their stability. Nicks and flaws had to be laboriously ground away using the grindstone, however.
Transporting and lifting the poles was largely done by hand with the aid of levers, rollers and inclined joists, over which we could roll the poles. It became clear that the people of the Bronze Age could only build regular wooden cages with almost vertical walls, if they had a method to reproduce dimensions and distances. One might consider standardized wooden rods or cords with knots. Additionally, to be able to build vertical walls they must have had a kind of plumb line.
Gate panels, bridge and palisade
The construction of the gate as a turnstile design with two panels was associated with many technical problems which had to be solved. The gate panels measured about 250 by 130 cm and without using any metal parts were to be made of approximately 5 cm thick oak planks. Turnstile designs have been found in several fortifications from the Bronze Age with perforated stone foundations in the relevant places. All structural timbers of the gate panels were worked on flat. We used the smaller blades as adzes and lo and behold, they were more than suited for this work (Ill. 4). When using adzes you can achieve a much higher accuracy than with axes because of the constant, slightly stooped posture and it was possible for us to produce very smooth surfaces, without having to make changes to the “axe blade”.
To begin with we squared off two approximately 3 meter long oak poles with diameters of about 25 cm at the thicker end into beams using the adzes mentioned.