English East Indiaman the President came to grief against Loe Bar in Mount’s Bay in 1684, losing most of her crew and what was described at the time as a “very rich lading, modestly judged of no less than a hundred thousand pounds… with much treasure of pearl, and diamonds”.

The wreck was even marked on a contemporary map of Cornwall produced by famous Dutch cartographer Van Keulen.

First reported by divers 20 years ago, the President was designated a protected site, with local divers Mark Milburn and David Gibbins of Cornwall Maritime Archaeology licensed to monitor it. Milburn's views on the threat posed by a new pipeline to the Anson wreck, also on Loe Bar, appeared on Divernet last week.

For many years the President's remains were covered by sand.

“Loe Bar is usually a dangerous place to dive, but the recent period of calm weather has allowed us to get in for the first time in months,”  says Gibbins.

“We were thrilled to see seven cannon and an anchor, and quickly realised that we were looking at a new part of the site that had never previously been recorded.

"You might think that most of the important wreck artefacts off this coast will have been found by now, but that is not the case. With every storm the sand can shift to reveal new treasures.”

The President’s last voyage was detailed in a contemporary pamphlet based on testimony of survivors William Smith and John Harshfield.

It includes a description of a battle with six pirate ships off India’s Malabar coast, with a roundshot from the President penetrating a pirate ship's powder magazine and blowing up the vessel.

“Cannon are common finds on the wrecks of merchant ships from the Age of Sail, when most ships were armed, but it’s very unusual to know that guns on a merchantmen were actually used, especially in such a colourful action and on the very voyage on which the ship was wrecked,” said Gibbins.

“It gives a special excitement to seeing these guns for the first time under water”.

Further diving is planned at the site - find out more at facebook.com/CornwallMaritimeArchaeology.

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