Walking the Line

In search of Mason, Dixon, and the boundary that changed America

?Todd Babcock walks down on a hill with his tripod.

Credit: ?Cameron Davidson

Under a dazzling blue sky, Todd Babcock and I are driving down a gravel road through rural Maryland, following the trail of two Englishmen who passed this way more than 200 years ago. It's a warm late-summer day, and after descending into a tree-lined valley framed by rolling hills, we reach a wood fence and park our silver pickup. Babcock, wearing jeans and black sunglasses, grabs a tripod, GPS receiver, and machete from the bed. Two bucks amble by, then head off into the surrounding tangle of brush. Babcock points to a grassy swath bisecting the valley—an old underground pipeline. "We can head down to the bottom of the hill there," he says, "and search for it."

We have come to find one of the stones marking the border between Maryland and Pennsylvania, otherwise known as the Mason-Dixon Line—the infamous divide between North and South during the Civil War. As the unofficial boundary between free and slave states, the line came to symbolize our fractured nation, taking on a near-mythic life of its own. The two men behind it, however, are often overlooked—and their story predates Antietam and Gettysburg by a century. Charles Mason was an astronomer, Jeremiah Dixon a surveyor, and in 1763 they came to the New World and ended a bloody dispute between Pennsylvania and Maryland by establishing the line between the two colonies. Their survey stands among the greatest scientific achievements of the time.

Today, aside from various artifacts and documents, the limestone boundary stones that the two men set are the most tangible reminders of their accomplishment. Todd Babcock, the chairman of the Mason and Dixon Line Preservation Partnership, has spent nearly two decades cataloguing and restoring the stones, and he's a little giddy at the prospect of finding a new one. "I always just want to touch them," he says. "They're a connection to the past, to Mason and Dixon."

Babcock checks his U.S. Geological Survey maps, pinpointing our location, then leads the way, a carved limestone marker lying somewhere in the woods ahead.

Establishing boundaries in the New World was no simple task. Imagine wandering through uncharted wilderness with maps notoriously vague and incorrect, no GPS device or Google Earth to confirm your bearings.

The boundary between Pennsylvania and Maryland should have been the 40th parallel of latitude, according to the royal charters that established the two colonies in the 17th century. The problem? Colonists were confused about where the 40th parallel ran. William Penn, the proprietor of Pennsylvania, realized that because it likely ran through Philadelphia, he stood to lose vital access to the Delaware River, which he desperately needed for trade.

Penn pushed for a boundary farther south, and for decades, the two colonies bickered about it, finally coming to blows. In the 1730s, a frontiersman named Thomas Cresap parceled out land for his fellow Marylanders along the Susquehanna River, harassed the Pennsylvania farmers who already lived there, and even killed one in a border skirmish.

Pennsylvania retaliated. After burning down Cresap's log cabin and murdering one of his men, a posse captured Cresap himself. A boisterous crowd gathered in Philadelphia to see the notorious rabble-rouser escorted to jail. "Damn it, Ashton," Cresap reputedly uttered to a guard, "this is one of the prettiest towns in Maryland."

In the end, Pennsylvania and Maryland agreed to a line 15 miles below the southernmost point of Philadelphia. The colonies eventually entrusted the job of delineating it to two preeminent men judged to be "intirely [sic] accomplished and of good character."

Mason and Dixon had just won international acclaim for readings they took during the astronomical event known as the Transit of Venus. Mason was clinical and reserved, Dixon, a free spirit. Upon their arrival, they first marked the north-south boundary between Maryland and modern-day Delaware. Then they embarked on a far greater challenge: the line heading west, the longest linear survey ever attempted.

Their team grew to 115, including cooks, shepherds, instrument and tent carriers, even a milkmaid. Using a device with a six-foot-long brass telescope that allowed them to establish their position in relation to the stars, the Englishmen observed the night sky during frigid winters and oppressive summers, making their calculations as lumbermen axed a narrow swath through the forest. The work was backbreaking and occasionally deadly—a falling tree killed two men. And the threat of hostile Native Americans was real. But Mason and Dixon persevered for nearly five grueling years, surveying more than 230 miles of the boundary between Maryland and Pennsylvania. (They stopped 21.5 miles short of their goal, to avoid confrontations with local tribes.) It was, says Edwin Danson, author of Drawing the Line, "the greatest engineering achievement of the American Enlightenment."

Babcock and I struggle through a thicket and come to a tree-lined gravel road, searching for the marker that Mason and Dixon established 138 miles from the boundary's start. Babcock is a full-time surveyor for Forino, a Pennsylvania-based developer, and on weekends, he squeezes in his work with the Mason and Dixon Line Preservation Partnership (an official project of Save America's Treasures; see page 40). He has inventoried about 200 of the 230 miles that Mason and Dixon marked, repairing broken stones and replacing lost ones with granite replicas.

"I guess we just walk down this way and keep an eye out," says Babcock. Sure enough, a few minutes later I see a stone standing about two feet high. "There it is!" I shout. We've discovered a milestone, set by Mason and Dixon, with an M on one side and a P on the reverse. (Every five miles, they established crownstones, which were carved with the coats of arms of the Calvert and Penn families.)

Babcock uses his machete to clear away the thick brush. "It's in pretty rough shape," he says, pointing to a missing chunk from the Pennsylvania side of the stone, which may be weathered and damaged but still looks distinguished. A tree trunk sits within inches of the Maryland side and appears to have protected it, as Babcock discovers to his delight: The engraved M is pristine. "I'm sure glad we came for this one," he says, as he traces the letter with his finger.

Babcock sets up his tripod with the GPS receiver over the marker and uses a wireless touchpad to turn on the device. The receiver gathers signals from satellites to establish the stone's coordinates to within a centimeter. "What I can do here in 15 minutes would have taken Mason and Dixon two weeks of nightly observations and calculations," Babcock says. "But you know, everything we're doing here is built on what they did. They were laying the groundwork."

Recording a precise location is vital because of the threats posed by vandalism, theft, and the occasional wayward tractor or snow plow. Indeed, some of the stones have been removed. "Once a marker is gone," says Babcock—if someone steals a stone to decorate a back-yard garden—"you've lost the work that Mason and Dixon did."

How to guard against such threats? Babcock relies on education. By spreading the story of Mason and Dixon and talking with homeowners who have stones on their property, he hopes he'll inspire people to look after the markers. For Babcock, that process often involves debunking myths: that Mason and Dixon were English spies, and that the word "Dixie" was derived from Dixon's last name. The most enduring legend? That Mason and Dixon marked a boundary accurate to within inches. In fact, they didn't understand the effect gravity had on the plumb bob that dangled from the bottom of their zenith sector. Attracted by large bodies of mass such as mountains, the plumb bob sometimes slanted to one side and caused Mason and Dixon to miss their mark by more than 800 feet.

The Mason-Dixon Line, Babcock discovered, actually resembles a sound wave, alternately curving above and below the intended location. Because commissioners from both colonies approved the boundary, it stands today. "When you account for that error," says Babcock of the plumb bob, "their accuracy was amazing."

In the late-afternoon sun, Babcock and I find ourselves with maps in hand once more, heading down a private driveway in search of stone number 139. We discover the marker—a milestone—on a farm that straddles the Mason-Dixon Line: The barn sits in Pennsylvania, an adjacent white two-story house in Maryland. "Someone did unfortunately paint the stone," says the goateed gentleman who answers the door. "My father-in-law threw a fit."

The engraved M is colored a bright red, the P a more sedate yellow. As Babcock sets up his GPS receiver over the stone, the father-in-law, Alton Hoopengardner, emerges from the house. A retired history teacher with an imposing white beard, Hoopengardner says his ancestors settled here in the 1840s—they lived in a log cabin down the hill—and his great-great-grandfather fought for the Union during the Civil War. As Babcock shares the details of his project, Hoopengardner nods in approval: "Symbols of our heritage are worth preserving," he says. "This was a wilderness area when those men came through here. If you read the stories of their travels, this was rough going."

Nearby Sideling Hill offers a prime example. The gradient was so steep that Mason and Dixon's men couldn't drag their wagons, laden with boundary stones, up the side. So they left the stones behind and used wood posts to mark the line the rest of the way. In the early 1900s, surveyors replaced many of the makeshift markers west of the hill with the original stones. (Exactly where the stones were deposited during the intervening 140 years remains a matter of dispute: either Fort Frederick, a French and Indian War outpost along the Potomac River, or Capt. Evan Shelby's farm, near present-day Hagerstown, Md.)

During the most trying times of their expedition, Mason and Dixon very likely thought about Harlan House, their one assured place of comfort and repose. They first visited the house soon after arriving in America. And they returned every winter, when the weather forced them to suspend the survey, giving them the chance to steel themselves for the hard work ahead.

A few weeks ago, I drove the winding backcountry roads near Embreeville, Pa., to Harlan House, a two-story stone structure adorned with gray-blue shutters. "I was looking for an old house, and I stumbled upon it," says its owner, Kate Roby. "I didn't have a clue what its significance was."

Roby, a veterinarian, fell for the place "like a ton of bricks." That was in 1983, she says, her glasses perched atop her jet-black hair as she shows me the house's original core, built in the 1690s. Though the inside was largely changed in later renovations, the oak beams and floors are original. So is the fireplace, in front of which Mason and Dixon made calculations and traded stories with the Harlan family, alcohol flowing freely.

"Mason and Dixon are notorious for being serious hardcore partyers," Roby says. Legend has it that a nearby creek was named Punch Run, she says, "because they had some big ol' party over there and made some serious punch." Another myth? Perhaps. But the surveyors did drink quite a bit. One of their supply lists called for "120 gals spirits, 40 gals brandy, 80 gals madeira wine."

Roby has done what she can to preserve the house. She replaced its roof and tore down a dilapidated Victorian porch in front. But despite the house's star turn in a momentous historical drama, Roby worries that eventually, no one may want to live here. That's because traffic on Stargazers Road, where the house sits, has gotten considerably worse.

We walk up a grassy incline to Stargazers' Stone, not a boundary marker but a point Mason and Dixon used to calculate their position some 15 miles north of where they started marking the line. A small rock monument built a century ago by the Chester County Historical Society surrounds the stone. Linda Kaat, a local preservationist, hopes to spruce up the site and build parking spots so that it's easier for people to visit. Roby worries that the construction might alter the landscape. But Kaat says she envisions a small parking area made of wood chips, nothing that would mar the view of the grassy plain that leads to the Brandywine River below and the bucolic hills beyond.

Landscape, after all, figures prominently in the story of Mason and Dixon. Mason was certainly inspired by the terrain the group encountered as it headed west. In his journal, filled with rows of scientific calculations, he described the view from the Appalachians in a rare moment of poetry:

From the solitary tops of these mountains, the Eye gazes round with pleasure; filling the mind with adoration to that pervading spirit that made them.

As I venture with Babcock into the rolling hills along the western part of the line, I discover that it's still possible to envision the pristine landscape that awed and inspired Mason and Dixon. With every passing mile, their achievement becomes even more staggering.

Of course, by settling the boundary conflict, Mason and Dixon enabled wary settlers to venture into previously disputed lands, and they gave later surveyors the scientific tools to chart an untamed wilderness. The beautifully carved stones that Todd Babcock is preserving are more than mere markers. They take us back to an earlier time, when two brilliant Englishmen helped transform the American frontier.

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