16th International Symposium on Boat & Ship Archaeology

46 16 th International Symposium on Boat & Ship Archaeology Robert Domzal National Maritime Museum in Gdansk, Gdansk, Poland Boats from the Silesian coal mine We are used to perceiving wrecks to be the objects found underwater or in the proximity of waterways. In January and April 2013 two unique boats were discov- ered in the layer of silt in a 200-year-old adit in the area of Zabrze (Silesia, southern Poland). They lay in a disused gallery of the adit about 22 m underground. The boats are similar in size: 5 metres in length and less than a metre in width. They had been made from the Douglas fir wood and were not used to transport the coal, as one might assume, but to carry the miners, tools and materials, possibly also for inspec- tions of the mine site. Vessels of this kind might have been used in mining from the middle of the 19 th century until the second half of the 20 th century. Despite numer- ous distortions, the condition of the boats can be considered to be good. Why did these vessels occur at such depth under the ground? At the end of the 18 th century the construction of the Main Key Hereditary Adit begun. It served as a drainage adit and as an underground water canal between Zabrze and Królewska Huta in Upper Silesia at the same time. It is one of the longest heredi- tary adits in Europe and the longest hydrotechnical construction in European coal mining. It is presumably one of the oldest galleries carved out in coal in the world. Author discusses the circumstances of the discovery of the boats, their construction and their utility details. Both artefacts are the property of the Coal Mining Museum in Zabrze. The National Maritime Museum in Gdańsk is now preserving the objects, which is not an easy task considering the combination of wood and metal. Part of the research revealing the inner construction details is conducted with the use of a special digital radiography lamp. 3D models were made with the Artec Eva optical scanner.