Kieran Hosty,marine archaeology manager at the Australian National Maritime Museum,said two critical measurements made by divers contracted by the museum last September finally convinced them that a particular wreck was the Endeavour.

Mr Hosty,who first dived on the wreck in 1999,accepted that making the announcement “had opened a can of worms” with the Rhode Island Marine Archaeology Project,but stands by the announcement.

“We are not driven by politics,we are using scientific fact and historical information to make this deduction,” he said.

“I know they are contesting that claim and they are stating that we have jumped the gun,but we have been working there for 21 years and on this particular site for more than four years,so it is hardly premature or jumping the gun,” he said. “We have got all our evidence there,and now it is time to make the announcement.”

Mr Hosty said two consulting archaeologists in the US,Dr John Broadwater and Joshua Daniels,had identified a measurement from the bilge pump to the bow of the wreck that correlated with the historical measurement for the Endeavour.

“In the process of doing that they also found a fairly unique scarf joint[a method of joining two timbers end to end] where the bow of the ship attaches to the keep of the ship and this bow scarf is shown on archival drawings of Endeavour,” he explained. “What they saw on the sea bed corresponds to exactly with what is seen on those plans. So,we have two very unique measurements.”

He said Dr Abbass’ team was unrealistically concerned with finding a “particularly unique artefact” - such as a ship’s bell - that could definitively identify a wreck as the Endeavour.

As for a separate claim that the museum had breached its contract with the Rhode Island Marine Archaeology Project,he said a contract between the museum and the group had in fact expired in November.

The Endeavour was originally launched in 1764,albeit under another name:the Earl of Pembroke.

Four years later it was renamed by the British Royal Navy and spent the next few years voyaging to the South Pacific and Pacific,firstly to record the transit of Venus in Tahiti in 1769 before charting the east coast of Australia and the coast of New Zealand in 1770.

Sold in 1775 and renamed Lord Sandwich 2,it was ultimately scuttled during a blockade by the British military in an American harbour in 1778 during the American Revolutionary War.

The discovery could also spark a cross-continent tussle over where to store the historical wreckage,with Mr Sumption noting that the vessel’s role in exploration,astronomy and science “applies not just to Australia,but also Aotearoa New Zealand,the United Kingdom and the United States”.

James Cook University history lecturer Claire Brennan said she did not believe it was greatly important whether the wreck discovered off Rhode Island was actually the Endeavour.

“As a historian,for me,the important thing about that voyage are the journals that are produced,that record what’s actually going on at the time of the voyage,” Dr Brennan said. “Finding rotten pieces of wood at the bottom of the harbour is not going to give me that kind of detailed insight into what went on in that voyage.”

With Cassandra Morgan

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