Exposed (but not for long): a relic from the exploration age

One of the most tantalising relics of Britain's seafaring history – a sunken 18th-century collier of the kind that took Captain James Cook to Australia – is being studied by archaeologists.

The vessel was exposed by low tides at Seaton Carew, near Hartlepool, seven years ago. Now the same tidal patterns have revealed the ship again, giving archaeologists a short period in which to work before she is covered again.

The collier has been described as the "articulated lorry" of the 18th century seas. Its robust form persuaded Cook to take two, including the Endeavour, on his voyages. After sailing to Botany Bay and back, Endeavourwas still in good enough shape to be refitted and returned to her original role transporting cargo.

The Tees Archaeology group has found the Seaton Carew ship was patched up at least once. She carried up to 100 tons of coal from Newcastle upon Tyne to London and the Continent and returned with timber.

There is a frustrating lack of evidence about the vessel. Newspaper records make no reference to a wrecked collier off Hartlepool, though the ship's position – pointing up the beach – suggests she was deliberately run ashore when her crew was in danger. Damage to the hull suggest it was battered by storms.

"Our main task yesterday was to take wood samples from the ship for the purposes of tree- ring dating, which will establish an age," said Robin Daniels of the archaeology group.

Several colliers in better condition have been found off eastern North America, where at least one has been preserved at an underwater national park. Endeavour was found by marine archaeologists searching Newport Harbour, Rhode Island, a few years ago.

The costs of removing the Seaton Carew vessel would be prohibitive but archaeologists fear the sea could wash the vessel away. "We've thought about putting sandbags in there but a few strong waves and they'll be gone," said Mr Daniels.