I was reading that old ships of the 1800's were 'sunk for preservation'. Anyone know why?

Question

i.e. US Brig Niagara was sunk at Misery Bay. Why wouldn't the water eat away at the ship too?

Answer 1

To keep them from being commandeered or destroyed by the enemy.

Answer 2

Boat wood (especially) when exposed to wind, sun, waves etc can get really beaten about.  If a boat is sunk. the sand action often rapidly covers the boat, - preventing any mechanical damage to the boat and obviously protecting it from the sun.  The deper it is buried in the sand, the less critters can get at it too.  Even rusting stops once there is no / little oxygen to act on the metal.  So yes - sinking/burying a boat really does perserve it.  

To preserve a (historical) boat one it is on the dry needs extensive and expensive  processes to remove salt water, and then to preserve wood with various preservatives..

Answer 3

well i believe what it meant to say was preservation of wildlife, that is why ships ar sunk, they make excellent habitats for animals and make great fake reefs and r fun to dive into.