A Copper Confessional

Sometimes history does not cooperate. Just when you think you’ve settled on a comfortable narrative of historical events, another stray fact appears to sabotage your conclusions. This one is about the copper bolts used to construct USS Constitution in the 1790s.

For many years people assumed these bolts had been manufactured by Paul Revere. Additional research revealed that he could not have made the bolts, but was hired to reduce the diameter of the British-made bolts by half an inch. At the same time, researchers at the USS Constitution Museum were certain that a number of bolts drawn out of Constitution’s keel in the 1990s were, in fact, some of the very same bolts Mr. Revere had reduced in 1795.

Here things stood until last fall, when the Museum was visited by Peter Hold and Mallory Haas, two archaeologists working for The SHIPS (The Shipwrecks and History in Plymouth Sound) Project. During a survey, the team discovered the remains of HMS Amethyst, a frigate lost in 1811 on the shores on the northeast side of Plymouth Sound. They recovered a number of artifacts from the wreck, including some copper fittings marked with the manufacturer’s name.

This led the USS Constitution Museum’s staff to look at the bolts drawn out of Constitution’s keel. On one side of the bolt was a curious marking. Although covered with verdigris, there were letters stamped into the copper. The first part of the inscription was abraded, but the remaining letters clearly spelled “YS MINE CO.” Inspection of a second bolt removed at the same time revealed the same marking, dispelling the former conclusion that Paul Revere had reduced the diameter of the bolts. Any attempt to reduce the diameter would have eradicated the markings, clearly establishing they could not have been manufactured or reduced by Paul Revere.

A search of British manufacturers led to the discovery of the Parys Mine Company of Greenfield Valley, Holywell, North Wales (the “PAR” of Parys was missing from the bolt stamps, possibly as a result of the workman rolling his hand as he struck the die with a hammer). Wales has rich deposits of copper ore, and in the late 18th century, Welsh mines produced huge amounts of the strategically important material. One of the largest concerns operating in the region was the Parys Mine Company.

By 1780, the Royal Navy and the British merchant fleet had a ferocious appetite for copper. Sheathing, bolts, nails, rudder fittings and a whole host of other ship fittings were made of the metal. But how did a product of the Parys Mine Company end up in Constitution’s hull. Unfortunately, so far the Museum has only been able to establish that the US Treasury Department ordered copper bolts from Britain in 1795. These were shipped from Liverpool, which was only a short distance from the Parys copper works. Beyond this, Museum researchers have been unable to discover contracts, receipts, bills of lading or other documents that might shed more light on the copper manufacturer who supplied the bulk of the bolts and sheathing for the new frigate. Nevertheless, the Parys Mine Company stamp on the two Constitution bolts prove that at least one of the shipments came from Wales.

(From Log Lines, USS Constitution Museum)

The two Parys Mine Co. marked bolts removed from Constitution’s keel in the 1990s.  (USS Constitution Museum Collection, US Navy Loan and Naval Heritage and History Command Boston)

The two Parys Mine Co. marked bolts removed from Constitution’s keel in the 1990s. (USS Constitution Museum Collection, US Navy Loan and Naval Heritage and History Command Boston)