Pattern of old wood. C/U of old trawler otter board.

The otter board is used on the mouth of a trawl net to keep it open. This board was used by a very small boat and is now in a museum. It spent its life saturated in sea water and crystals of sodium chloride and minerals like chlorine, sulfur and calcium helped to preserve the timber. Now the board is outside and the salts regularly leached with rainwater. The wood is showing signs of decay, the wood becoming brittle as outbreaks of dust like mold discolour the wood surface. The iron bolt has corroded together and iron oxide has stained the wood.