GROTON -- Earl Carter's garage sits in a quiet, heavily wooded neighborhood along Lost Lake. The garage doubles as a workshop, and it shows decades of use. Piles of seemingly random scrap metal line one wall; old, steady tools sit ready to continue the work they have done for years.

The entire upstairs floor of the building is a miniature museum of Groton history, packed floor-to-ceiling with pictures and trinkets and old documents, like the first tax bill that Groton received from the newly formed state of Massachusetts. Carter sometimes calls it his "Myseum," a play on the fact that he runs it all himself.

And then, in the middle of the garage lies what Carter calls a "national treasure" -- a 1,200-pound cannon that militia, including members from Groton, looted off of a British ship during the Revolutionary War's first naval battle using it at the Battle of Bunker Hill, now sitting atop a replica carriage Carter constructed with two-century-old wood left over from the construction of the USS Constitution.

The cannon's cast-iron barrel survived in Groton for the next 230 years, occasionally bouncing from one location to another and often being forgotten. So last year, Carter, who said his fourth great-grandfather Ralph Farnham was the last living survivor of Bunker Hill, decided to begin restoring the cannon.


And the barrel is in such "pristine" condition that Carter now believes the cannon -- which he affectionately nicknamed "Pit Bull" -- is one of the finest of its kind in the country.

"There are no museums that have anything this nice," he said. "The head curators of the museums all want it."

Carter will display the cannon at this month's Grotonfest, and it will be the first time it is shown in public since he began his project.

He traces its history all the way back to the Battle of Chelsea Creek, a small naval engagement that took place in May 1775 midway between the fighting at Lexington and Concord and the Battle of Bunker Hill. An article in the New England Quarterly called the events of Chelsea Creek "The Revolutionary War Battle America Forgot."

The battle started, according to the article, when a number of provincial forces attempted to herd livestock off of Hog Island and burn bales of hay near Chelsea, thereby damaging supply lines on which the British troops depended. But columns of smoke alerted the British, and so the HMS Diana was ordered to sail up Chelsea Creek and prevent the militia from escaping.

Little did the British commanders know that would prove a costly decision. The Diana got dragged into a lengthy skirmish with militia who were dug in on land, and by nightfall the tide went out and the wind died, leaving the ship stuck in the mud with no escape. British troops eventually fled, and the colonial fighters -- including a group led by Groton's Capt. Asa Lawrence -- stole the Diana's cannons and then razed it.

Carter said four of those cannons went on to be used about a month later at the Battle of Bunker Hill, but three were lost in the carnage, leaving just one.

And now that one sits in Carter's garage.

Victor Mastone, director of the state's Board of Underwater Archaeological Research, described Carter's project as "very important" and said in his time on the board, he had only ever heard of one cannon from the era being found underwater.

"We've been studying (the Battle of Chelsea Creek) and we really haven't gotten any battlefield remains," he said. "This is like genealogical research or DNA. You don't always get these real, direct connections with objects ... That it's (also) associated with the Battle of Bunker Hill makes it an even more exciting piece."

After Bunker Hill, Carter said the cannon came to Groton. He tells the story like this: it wound up at Mathias Farnsworth's farm, near what is now Route 119, for safekeeping so that the British could not find it. It was shuffled around town a few times. Carter said a number of Groton historians stretching back more than a century mention the cannon's existence in their accounts.

In 1972, the Groton Historical Society re-discovered it behind a building near Lawrence Academy. Someone had built a miniature outdoor display for the cannon, but by the time the Society found it, the barrel was covered in vines "30 to 40 years old," Carter said.

Carter, who is a former curator of the Historical Society, did not see the cannon until 1995 or so, and he did not start restoring it until about a year ago.

"I knew it was still there," he said. "I figured I wanted to take it and do something with it ... Then I started to realize what I had here, and I said, 'Oh my God.'"

Although the carriage on which the cannon sat had completely decayed, the barrel itself was in excellent condition and needed only light sand-blasting and an enamel coating.

Carter shows photographs he took of naval cannons from a similar era on display at various museums in Washington, D.C.; most have rugged, uneven surfaces or small chunks clearly missing, which Carter said is likely because most spent some time submerged in saltwater before being recovered.

But his cannon, because it was looted off of a ship and then hidden in Groton, never was underwater. Its surface is comparatively smooth, and the details are sharp, like the crown seal honoring King George III and the numbers indicating the barrel's weight.

"I wouldn't be surprised if it's one of the finest in the country," Carter said.

His project did not end with the barrel, though. He wanted to build a replica carriage that would be as authentic as possible to what was aboard the Diana, both in terms of design and material. So he used old nails and fixings and even build a kiln so he could forge the trunnion caps.

By a stroke of luck, a friend of his had just purchased some logs of "early-growth live oak" from the Charlestown Navy Yard that Carter said were leftover from construction of the USS Constitution and were buried in a swamp for preservation for more than 200 years.

"These are the logs that were saved after building the Constitution," Carter said. "I said, 'That's the wood I want to use!' So you gild the damn lily with wood from the Constitution. How can you beat it? People won't believe when you say it. But I'll prove it."

It has been a labor of love for Carter, who estimates he has spent about 1,500 hours on the whole project. But that is worth it for something with as much historical significance as he says there is.

"I don't think there's another object I can think of here in New England that is anything like it, that was taken off of a British ship and used (by the Americans) and is still in relatively pristine condition," said Michael Roberts, an archaeologist and member of the Groton Historical Society.

Groton has a number of connections to the Revolutionary War, and smaller artifacts from that era such as buttons from a jacket are not altogether uncommon, Roberts said. The cannon, though, is in "a totally different category."

"This is a touchstone to the Revolutionary War," he said. "You can put your hands on it and go right back to that war and be standing in the midst of history."

While Carter has extensively traced the cannon's past, its future is uncertain. He will unveil it to the public at Grotonfest on Sept. 24, but no one knows where it will go beyond that. Carter wants to keep it in Groton, but thinks it could be "right at home" in a national museum. Mastone said his philosophy is "the more local, the better" and supported the cannon staying in town.

One thing is clear: there's no more room in his upstairs museum for Carter to put his latest discovery.

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