Waldemar Ossowski - Archaeologist, curator, certified diver. Graduate at Institute of Archaeology and Ethnology at the University of Nicolaus Copernicus. Dives since 1986, recently mainly as a professional diver. Since 1994 he has worked in the Underwater Research Department in Maritime Museum. His work is mainly based on boats and ships research, both in Polish sea areas and on inland waters. Author of over 80 scientific publications, outreach articles and two monographs about monoecious boats and river vessels. He headed the English underwater studies about “General Carleton” wreck, which sank in 1785 near Dębki in Poland. He was editor and co-author of a book publication, which presents the results of research of this ship, published in 2008. In recent years, he was involved in newly discovered archaeological objects in the vicinity of the port of Gdansk, in the “Dead Vistula” and studied the remains of a medieval ship called The Copper.