Restoration Notes – “Copper Bottomed”

USS Constitution’s copper sheathing is being replaced during the 2015-2017 restoration. This will be the fourth time in the past century that all of the ship’s copper is replaced.

On March 27, 1794, Congress passed the “Act to provide a Naval Armament” which authorized President George Washington to create the new United States Navy. Each of the six frigates that made up the new U.S. Navy was to be “copper bottomed”, i.e., covered below the waterline in thousands of pieces of overlapping copper sheets. This prevented boring mollusks from destroying the wood and allowed for greater ease in cleaning marine growth from the ships’ bottoms.

In a letter dated April 21, 1794, Joshua Humphreys, a shipwright from Philadelphia who was the principle designer of the original six frigates, listed “An estimate of the quantity of Timber Plank &c for a frigate…” the size of Constitution, including the copper needed – “12000 feet of sheet copper for bottom”.
Over the years Constitution has been re-coppered at least 12 times. Throughout the 19th century, Constitution’s copper sheathing was periodically replaced and, beginning with the 1833 docking of the ship in the Charlestown Navy Yard, souvenirs were fashioned from the copper sheathing (a miniature copper kettle was made from copper removed in the mid-19th century).

Souvenirs made from copper removed from USS Constitution are available at the USS Constitution Museum Store: Jewelry and Limited Edition Medallion.

USS Constitution Restoration 1858 – (Photo Credit:  US Constitution Museum Collection)