The canister looks like metal, and isn't airtight anymore. It has barnacles on one side, which makes it likely it was probably floating, rather than sitting on the seabed.
How did it manage to float so long without sinking? It looks structurally compromised from the photograph.
Maybe it was on the seabed and the barnacles were working their way up when it was brought to shore tumultuously? Or maybe it was floating and the processes that brought it to shore caused that damage?
The canister looks like metal, and isn't airtight anymore. It has barnacles on one side, which makes it likely it was probably floating, rather than sitting on the seabed.
How did it manage to float so long without sinking? It looks structurally compromised from the photograph.