Probably at the beginning of the 30-year war, an interesting new development appeared – leather cannon. It consisted only of relatively weak metal barrel, which was panelled with wood and wrapped in a few layers of wet bull skin. After it dried, the skin perfectly clinged to the barrel. A gun constructed in this way was fairly light and easy to move. Its disadvantage was its a low durability of the barrel. A barrel long 90 cm and weighing 8,5 kg bears in an oval coats of arms with a cartouche and a crown the symbol of the Duke of Tuscany Ferdinanda II. Medici (1610–1670).