An archaeologist is taking a second look at a small cannon found by fishermen off the Virginia coast more than two decades ago in hopes of determining how it got to the bottom of the ocean — and who left it there.

Rod Mather, a professor of maritime history and underwater archaeology at the University of Rhode Island, has studied the 25-square-mile area surrounding the site where the cannon was found the past two summers.

Some historians believe the 4-feet-long, 300-pound cannon, which was loaded when it was found 24 years ago, is an English cannon from the 1580s, making it one of the oldest English artifacts ever found in the Americas.

Others argue that even if the cannon dates back to the 1580s, it could have been in use in the early 17th century when more ships were up and down the Virginia and Carolina coasts.

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"If it's a shipwreck, and it's an English shipwreck, it would be the earliest English shipwreck in the New World," Mather said. "If you think about what we know about American history, the fuzzy part is the part about the early exploration of America."

Mather also questions if the cannon could have even more significant historical value — possibly answering the question of what happened to the so-called Lost Colony.

The "disappearance" of 117 English colonists in the late 1580s on what is now Roanoke Island in North Carolina has baffled experts.

Mather suggests the cannon possibly could have been left by the colonists — either because their ship sank or by simply falling overboard — as they fled in search of better living conditions.

Curators at East Carolina University in the mid-1980s — where Mather was a graduate student who worked on the cannon — dated it to 1587 and determined it was an English, land-based piece called a "falcon."

John White, whose 1590 expedition to Roanoke discovered that the colonists were no longer there, wrote in his journal: "From thence we went along by the water side, towards the point of the creek to see if we could find any of their boats or pinnaces, but we could perceive no sign of them, nor any of the last falcons and small ordinance (sic) which were left with them, at my departure from them."

"It's easy to run wild with that," Mather said. "But it's also true."

Many historians believe a faction of the Roanoke colonists fled the island, possibly to the Chesapeake Bay or other nearby areas.

While Mather doesn't necessarily favor the Lost Colony theory, he hopes to find evidence of a shipwreck.

He is aided in his search by the National Oceanic and Atmospheric Administration ship Thomas Jefferson, based in Norfolk. The ship's advanced side-scan sonar capabilities and other devices help him map the ocean bottom to find any irregularities that might indicate other artifacts or ballast stones from a ship.

The NOAA's Office for Ocean Exploration funds Mather's work, which is in its early stages.

He has yet to find anything that demonstrably appears to be a shipwreck, but Mather is undeterred. Still, he has his doubters.

Ivor Noel Hume, former chief archaeologist at Colonial Williamsburg and noted author on America's early English settlements, doesn't believe the Lost Colony possibility.

"There is nothing to be said about it," Noel Hume said. "It's a loose cannon. It really is."

Noel Hume said the cannon more likely was jettisoned during a storm, possibly after it had been in use for decades, off any of a number of ships sailing up and down the coast after the 1607 founding of Jamestown, England's first permanent settlement in North America.

"A lot of ships went up and down the East Coast. A lot of ships sunk that we don't know about," he said.

"A pirate would take on cannon and put it on another ship. They would keep on using them. You could argue that gun was still on a ship in the 1620s."

He also said he doesn't agree with the cannon's 1580 dating: "You can't date it that closely, I think."

Mather and his colleagues face months of work to analyze the data collected for his July trip to the site, which will determine if he returns to the site.

"We have different sensors that we're using that are starting to point to specific areas," he said. "There's some cause for optimism."