Sailing with Copper

Back in the days of wooden ships it was normal practice to sheath the lower hull in copper, this was done to protect the wood. Copper handles salt water better than wood does, copper also protected the wood from sea creatures such as worms and barnacles. 

If you need proof as to the longevity of copper vs wood in the ocean, here's a picture of a sunken ships hull, tell me...you see much wood left?