Nitrogen gas protects a 440 year old cannon

In September 2007 a strange object was salvaged from the sea outside the harbour of Visby. A 4,5 meter long cannon from the 16th century made of iron and placed in a wooden gun carriage. The cannon is from the Danish-Lübecker fleet, which sank off Visby harbour in a heavy storm in the summer of 1566.

The cannon is an early model that was used both at sea and on shore. The wheels and the separate gunpowder cartridge are missing. Since the cannon is made of iron and wood, and has been lying on the bottom of the sea for over 440 years, it is fragile from corrosion and very sensitive to oxygen exposure.

After preservation the cannon will be put in a specially made Milox Display Case filled with nitrogen gas and then put on public display at the Gotland Museum.