The use of copper sheeting to prevent boring mollusks from ruining the wood of ships was a relatively new technology at the birth of the US Navy, but was quickly adopted world wide.
England’s Royal Navy began experimenting with copper-cladding its warships in the early 1760s and found it extended the life of the ships by preventing boring mollusks from destroying the wooden hulls. Below-the-waterline copper sheathing also allowed for greater ease in cleaning barnacles and crustaceans from ships’ bottoms. USS Constitutionand the other five frigates of the original U.S. Navy were each copper-clad before launching, per the instructions of Joshua Humphreys, the frigates’ designer.
When coppered in the summer of 1797, Constitution‘s lower hull required “12,000 feet of sheet copper” and thousands of copper nails. There is no 18th century plan of the layout of the copper sheathing, but it is probable that the workers at Edmund Hartt’s shipyard began at Constitution‘s stern, down at the keel, and worked their way both forward and upward with row upon row of copper. Each sheet would have overlapped one inch on all sides, with the vertical joints between the sheets facing aft. This created a smooth “fish scale” affect to the hull, thereby preventing the sheets from being lifted by the action of the water. It is understood that the Royal Navy laid its warship copper with the horizontal joints facing upwards and it is possible that Constitution‘s copper was so installed, as depicted in the illustration below.
One minor bit of trivia that always amuses me- the US Naval Surface Weapons Center at Crane, IN, maintains a section of white oak specifically to support repairs to USS Constitution.
XBradTC 
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