Captain Cook's Endeavour may be found

A shipwreck found at the bottom of a US harbour is looking increasingly likely to be the Endeavour.
A shipwreck found at the bottom of a US harbour is looking increasingly likely to be the Endeavour.

The search for Captain James Cook's Endeavour may soon be completed, with archaeologists announcing a shipwreck found at the bottom of a US harbour is increasingly looking like the historically significant vessel.

A joint US-Australian effort to identify the sunken ship has been under way for more than a year in Newport Harbor, Rhode Island.

"We have definitely entered that exciting phase now," Australian National Maritime Museum director Kevin Sumption told AAP on Sunday.

An event was held in Rhode Island on Sunday to announce the latest developments.

Divers have been looking for clues to either confirm or rule out the wreck as the Endeavour, but everything is pointing toward it being the ship Captain Cook sailed on his historic voyage to Australia and the South Pacific from 1768 to 1771.

The results of the joint investigation by the ANMN, the Rhode Island Marine Archaeology Project and SilentWorld Foundation could be completed by Christmas.

The dive teams have carefully dug thin trenches along the ship to examine the shape of the hull and the keel.

The keel is critical; the Endeavour's was made of elm.

"The forensic wood sampling we will be doing over the next couple of months will be rather critical - if this particular piece of the keel turns up to be elm, that will be part of the puzzle that kind of allows us to say 'Yes, this is Endeavour'," Mr Sumption said.

The Endeavour's colourful history continued after Captain Cook's expedition.

The vessel was re-fitted into a transport ship and renamed the Lord Sandwich II.

It is believed the British sunk the Lord Sandwich II and 12 other British ships in Newport Harbor as a tactic to block the French Navy, allies of rebelling American colonists, from entering in 1778 during the American War of Independence.

Australian Associated Press