WESTPORT — Thornton Owen Simmons may be a miller, but you could hardly call his job a grind.

The 67-year-old Little Compton man acknowledges that he’s got a pretty good gig running one of the country’s oldest continually operating grist mills. Gray’s Grist Mill, just over the Westport line but still claimed by Adamsville residents as their own, has been going strong for 300 years or more and has been producing Rhode Island Jonny Cake Corn Meal since 1878.

“I grind on the weekends, put the orders up during the week and send it out,” he said. “It’s four hours a day and you get to meet new people.”

But surely learning the fine craft of grinding white flint corn using 1.5-ton millstones, a “damsel,” a chaff bin and other tools of the trade must have taken many years to perfect.

He laughs. “It only took me an hour and a half. I’m not kidding you.”

Of course, Mr. Simmons has a helpful tool that wasn’t available to his 18th and 19th century counterparts: electricity. While the mill was previously powered by water and then a turbine, it now relies on a 10-horsepower motor — hidden from view, of course.

“With the electric motor, it really made it easier to control,” Mr. Simmons said.

Still, this working museum of a mill is a testament to the old way of doing things. The stones, the hopper, crane — they’re all there. You can still hear the rush of the water running from Adamsville Mill Pond across the street and under the mill where the water wheel used to be. (The mill plans on reverting back to turbine power and using the motor for supplemental power within the next few years.)

Even Mr. Simmons, wearing a vest and sporting a neatly trimmed white mustache and goatee, appears to have stepped out of the past. You can trace his lineage back to Moses Simmons, who first came to American on the ship Fortune in 1621, just a few weeks after the first Thanksgiving. A carpenter and contractor who didn’t start grinding and managing the museum and store until 2002, Mr. Simmons has, in fact, got cornmeal in his blood.

“My ancestors had the first grist mill in Little Compton — Simmons Mill Pond,” said Mr. Simmons, who believes the mill was operating by the early 1700s until it was sold in the late 1800s.

The exact date of origin for Gray’s — it got its name when Philip S. Gray bought the mill in the early 1880s — is also unknown. “They can trace the original deed back to 1717, when it was called Taber’s Mill,” said Mr. Simmons. However, he believes there was a working mill on the site by the time the town was incorporated in 1675.

Grist mills were common in those days since they provided residents with meal for livestock and flour for baking. “They needed something to grind the corn,” said Mr. Simmons.

Adamsville Mill Pond — neatly bisected by the state line — was the mill’s original energy source. “It used a water wheel originally and then they changed it over to a turbine which took a little renovation to do,” said Mr. Simmons, noting that the turbine got knocked off its foundation in the 1938 hurricane.

By the arrival of the 20th century, most grist mills had stopped cranking, but its last two owners have kept Gray’s alive. John Hart purchased the mill in 1939 and later installed a 1946 Dodge motor salvaged from a Cain’s mayonnaise truck that had hit a stone wall, according to Mr. Simmons.

“You shifted the transmission, driving the belt that was turning the stones,” he said.

The extra power was needed to supplement the water power from the pond, whose levels had become more and more unreliable.

“That was really an improvement back then,” he said. “Even now, I can open the sluice gate and that pond will be drained down in four hours. So even the old mill had to wait for that pond to fill back up. In the old days they were lucky to get about four hours of grinding.”

Gray’s was powered entirely by the Dodge engine by 1960 and a later miller used a tractor to operate the mill. “You couldn’t grind in the rain because the belt kept slipping off,” said Mr. Simmons.

Ralph Guild, a New York City resident who summers in Westport, bought the property from the Hart family in 1980 and made numerous renovations to preserve its historical integrity. “Ralph Guild renovated the mill just to keep it running and so people could come in and see how it’s done,” said Mr. Simmons.

Grinds, bags it himself

And with that he flips a switch and fires up the mill. A low rumble tickles your toes and the sweet smell of ground corn fills the air. (Mr. Simmons buys up to 500 or 1,000 pounds at a time of Narragansett Indian white flint corn — grown only in Rhode Island — that’s already shelled.)

As the whole, dried kernels are dropped into the hopper, a rotating stick called a “damsel” knocks the corn into the eye of a 56-inch granite stone. “You really got a finer grind to the corn,” said Mr. Simmons. “Most grinding stones are only four feet wide, and this one here is 56 inches.”

The stone grinds the corn to a fine consistency, and it’s further sifted through a fine mesh as the finished product falls into a large bin below. The coarser pieces of the bran (the outer layer of the corn) are separated into a separate bucket. Very little goes to waste — Mr. Simmons feeds the bran to the ducks across the street.

After that he takes the bins — they can hold up to 60 pounds of cornmeal — into a kitchen area and bags the meal himself. He works fast — “it probably takes 20 minutes to a half hour” to bag 60 pounds of meal into one- or two-pound bags, he said.

“Some people buy the meal right off the stone. I can take it right out of the bucket and bag it — there’s no additives or preservatives,” said Mr. Simmons.

The jonnycake meal — Gray’s also produces pancake and waffle mix using local yellow corn with wheat and rye — is sold on site as well as in local stores and is shipped as far away as Florida, California and England.

Keeping history alive

Most grist mills closed by 1900 and only about a dozen are still in operation in Massachusetts and two in Rhode Island, said Mr. Simmons. “But this is the oldest continuous mill still grinding and selling commercially,” he said.

Mr. Simmons, who remembers visiting the mill as a boy with his father, said he’s proud to carry on the proud tradition of his ancestors.

“It’s taken me 60 years to find a 360-year-old job,” he said.

Gray's Grist Mill

638 Adamsville Road, Westport

508/636-6075 or www.graysgristmill.com