Since The Day started CuriousCT in February, readers have submitted more than 350 questions. Reporters have answered many of them, some about how government spends our money and others about an empty building in their town.

These three questions we're calling "This and That."

How do you mow that?

Fort Trumbull, the five-sided fort built to protect New London Harbor, is an imposing structure constructed mostly of granite quarried from nearby Millstone Point.

Earthen strips top the walls at two sides of the fort and, at this time of the year, are covered with grass and wildflowers.

A reader sent a question in to The Day as part of the CuriousCT initiative asking how those grassy strips are maintained.

The answer, says Michael Gore, an interpretive guide at Fort Trumbull State Park, is a string trimmer. About once a month, maintenance crews climb to the top of the fort with a weed wacker and trim back the grass to a reasonable length.

There is a steep slope on parts of the grassy area, and workers use a harness in spots for safety.

Those earthen sections were part of the original design of the existing fort, which was built between 1839 and 1852, to absorb the impact of cannonballs during an attack. Visitors can access two stone spiral staircases, along with an elevator, to get to the top of the fort.

The grass-topped section of the adjacent ravelin — an angular stone structure at the front of the fort that protects the entrance from attack by land — is trimmed in the same fashion.

The fort is part of the 16-acre Fort Trumbull State Park and is the third structure built at the site. The original fort was built in 1777 to protect the harbor from British attack.

It subsequently served as a recruiting station during the Civil War and was rebuilt as part of a coastal defense system in advance of the War of 1812. In 1910 it became home to a program of instruction for the Revenue Cutter Service, the predecessor to the U.S. Coast Guard.

In 1917, to counter the threat of German U-boats torpedoing U.S. ships during World War I, the U.S. Navy and the National Research Council established an antisubmarine research center at the fort, called the Navy Experimental Station at New London.

During the Cold War, Fort Trumbull also was home to a research site known variously as the Navy Underwater Sound Laboratory, Naval Underwater Systems Center and Naval Undersea Warfare Center.

The park is maintained by the state Department of Energy and Environmental Protection and open Wednesday through Sunday from 9 a.m. to 5 p.m. from May 21 through Labor Day. The Fort is closed between Labor Day and Memorial Day Weekend.

— Greg Smith

Why blast the train whistle?

Anyone living near the train tracks running through the southern end of Niantic knows that trains passing through the area tend to blare their horns at seemingly random times both day and night.

Two readers sent in questions to The Day as part of the CuriousCT initiative asking why trains sound their horns throughout the area, despite no nearby road crossing.

The most common reason, according to Jason Abrams, a spokesman for Amtrak, is most likely due to railroad workers on the tracks.

"We do most of the track maintenance at night, so our night train and the freight train that (also) runs at night are most likely sounding (their horns) for workers on or near the tracks," Abrams said, while also explaining that besides Amtrak trains, Shoreline East trains and Genesee & Wyoming, or GWRR, freight trains also run through the area.

Abrams also said that trains do not blow their horns for the person sitting in the control cabin of the Niantic River train bridge, who is an Amtrak employee, but will sound their horns if they see an employee or person near the bridge.

According to Federal Railroad Administration regulations, trains approaching "any roadway workers or roadway maintenance machines" on the track must sound an initial horn warning, and subsequent warnings, if necessary.

FRA's train horn rules also state, "locomotive engineers must begin to sound train horns at least 15 seconds, and no more than 20 seconds, in advance of all public grade crossings."

If a train is traveling faster than 60 mph, engineers will not sound the horn until it is within a quarter-mile of the crossing, even if the advance warning is less than 15 seconds.

There is a "good faith" exception for locations where engineers can't precisely estimate their arrival at a crossing and begin to sound the horn no more than 25 seconds before arriving at the crossing.

Train horns must be sounded in a standardized pattern of two long, one short and one long blasts. The pattern must be repeated or prolonged until the lead locomotive or lead cab car occupies the grade crossing. The rule does not stipulate the durations of long and short blasts.

The maximum volume level for the train horn is 110 decibels, which is a new requirement. The minimum sound level remains 96 decibels.

— Mary Biekert

Mystic is many things

Mystic is a village, a fire district, a sewer service delivery area, a ZIP code and a census-designated place, Stonington Director of Planning Jason Vincent said.

And so there is no single answer to a reader's question: What are the true boundaries of Mystic?

Under the village concept, the area in Groton and Stonington doesn’t have a defined geography, Vincent said.

“It could be argued that the many historic districts comprise the village, but it would leave the more modern expansions of the village out,” he said.

Groton Planning and Development Director Jon Reiner agreed that a village — a characteristic common in New England — really comes down to a sense of place, rather than an area with official boundaries.

“Many people describe and define villages and their boundaries in different ways,” Reiner said. “To some it is a place; to some it is a ZIP code, 06355; to others it is home, or a village or a tourist center.”

Mystic also is a fire district, a form of local government in Connecticut, and most people probably use the fire district boundaries to define Mystic, Vincent said.

Mystic Fire Chief Frank "Fritz" Hilbert agreed that Mystic, in general, is broadly defined. The Mystic Fire District, however, follows specific boundaries and is south of the Old Mystic Fire District.

Mystic Fire District's boundaries are laid out in maps and a legal description — but they can be convoluted.

On the Groton side, the Mystic Fire District is bordered on the east by the Mystic River and stretches as far west, at points, as Flanders Road. Its northern boundary zigs and zags but extends as far north as just below Sandy Hollow Road at points.

On the Stonington side, the fire district is bordered on the west and south by the Mystic River. On the east, it borders the Quiambaug Fire District, with the Pequotsepos River cutting diagonally through the southeastern corner. Roughly, the Mystic Fire District extends as far north as the southern line of the Elm Grove Cemetery and Morgan Street, where it borders the Old Mystic Fire District.

The reader who posed the question said people as far away as Flanders Road, and north of Gold Star Highway state they live in Mystic — and asked: "Is that true?"

Hilbert said that depending on where people live on Flanders Road, they could live within the Mystic Fire District's boundaries, but north of Gold Star Highway is considered part of the Old Mystic Fire District.

The 06355 ZIP code is not pertinent to the fire district and extends well past the district's boundaries, he said. It covers an area more than twice as large as the fire district, extending to the north and east, and as far south as to encompass Ram Island.

There is also a U.S. census-designated place classification for Mystic, Vincent said, with a map showing different boundaries than the fire district, extending much further east into Stonington. On the west, it includes less of Groton.

And then there's the Mystic Sewer District in Stonington, which covers the eastern side of the community.

— Kimberly Drelich