Zalai Múzeum 12. 50 éves a Nagykanizsai Thúry György Múzeum (Zalaegerszeg, 2003)

Mc Quirkné Glattfelder Lucia: A Hahót–Telekszeg-i 15–16. századi vízzel telítődött favödör konzerválása cukoroldattal

A Hahót - Telekszeg-i 15-16. századi vízzel telítődött favödör konzerválása cukoroldattal 179 The conservation of a 15-16^ century waterlogged wooden-bucket from Hahót - Telekszeg using sucrose-solution treatment Judit Kvassay, archaeologist of the Museum of Zalaegerszeg, made excavations between 1987 and 1992, as a part of the Microregion Project of the Hungarian Academy of Sciences. During this period she found different objects from the Bronze Age, Árpád Age and late medieval period. In a late medieval house she found a well in which at a depth of 184 cm, on the eastern side, bungs and bottom-pieces of a wooden bucket were lying. I had the pleasure to do the conservation and restoration, applying a quite new method, using sucrose-solution. The process started in 1993. At that time a lot of waterlogged wooden objects were found all over Hungary, and were waiting for conservation. This fairly new conservation method was experimented by a collague András Morgós, National Museum and I in the 80s, because there was a real need to find a cheap, short period process, usable in the case of a big amounts of wood, and ready to work by this method in poorly equipped conservation labs everywhere in the country. In contrast to the widely used PEG-method , this process, using sucrose-solution gives a more favourable result, the treated wood retains a natural look, can be glued and fixed with different adhesives and can be completed if necessary. One further advantage of this method is, that it does not need heating during conservation. The only problem of this method is to find a safe biocide, which prevents the sucrose-solution from fermenting. After completing our experiments at the end of the 80s, I succesfully conservated waterlogged wood found in a medieval well of Márianosztra-Toronyalja, in Northern-Hungary. So I started the process using this method to preserv the wooden-bucket of Hahót-Telekszeg with an other wood-material found during motor-way excavations in Western Hungary. After taking photos, making drawings, numbering the wood-pieces and measuring their weights in the Autumn of 1993,1 started the conservation. In this way I could follow the building-in of the sugar and the loss of water. Because of the osmotic pressure, the condensed sugar-solution forces the water out and replaces the water which worked as a static holder for the deteriorated wood-structure. During the sugar crystalizes within the capillars of the wood, working as supports, giving strength to the demaged wood. Without this process, the wood would have cracked, shrank and collapsed irreversibly. Using biocide to protect the sugarsolution is always a very delicate task. The conservator has to face life hazards using strong biocides while producing poisonous solutions which are enviromentally hazardous, thus requiring special treatment. If the biocide is not effective enough, the solution can easily go bad and will not be able to strengthen the deterioreted wood. To find the proper biocide and to use it in a safe way needs more time and experimentation. In my case, using NEOMAGNOL pills again and again, I could avoid the fermentation of the solution. The conservation took part in a metal bath using 60 liters of water and 70 kg sucrose, which was added to the water with a 5% sucrose 3 days frequency. After I achieved the right concentration, I left the wooden objects in the solution till their weights stabilized. During the conservation, the pieces must be measured many times to check, how the process is progressing. On the 10th of March 1997 I took out the woodfinds from the liquid and, coverd them with clear textiles and put them under sand to dry. The aim of drying the wood under sand is that in this way the inner and outer structure lose water and humidity simultaneously and very slowly so no cracks, shrinkage or other kind of demage will occur to the wood after drying. Of course, during this period measurements must be carried out as well to control the loss of water. When the weight of the wood-pieces has stabilized, the conservation is finished. In my case it finished in August of 1999. After lifting the wood out of the sand, I completed the missing parts using EPORAPID two-component epoxy-resin, mixed with sawdust. The bucket-bung surfaces did not show any apparent signs of a once used hoop, because in order to hold the bungs together, they used willow branches, which were widely used at that time. To keep the bungs together, I used UHU-COLL adhesive. One of the main advantages of this sucrose-solution method is that the treated wood-pieces can be glued together without any diffidulty. Nowadays conservation and restoration require such methods which are reversible and do not provide a final solution to the problem of preserving an archaeological object. Chemistry and modern sciences can maybe provide tomorrow or in a year a much better way or method, so we have to be ready to find better and better solutions which can preserve the finds without losing their natural appearance, information-holding surface and role to be a messenger between what once was and today man.