CORNISH-WINDSOR COVERED BRIDGE MAP LONGEST COVERED BRIDGE MAP IN THE UNITED STATES
Builders soon learned that, without a roof, a wooden bridge won’t last long.
December 8, 1989, was a cold day in Cornish, New Hampshire, well below freezing, with winds that made it feel even colder. Still, more than a thousand people showed up to celebrate the reopening of the Cornish-Windsor Covered Bridge, the longest two-lane covered bridge in North America and the second-longest such bridge in the world.
Straddling the Connecticut River, the bridge was built in 1866 by James Tasker and Bela Fletcher, two local men who, though uneducated, successfully used their practical, often intuitive expertise to build a lasting truss structure. Three earlier bridges had crossed this spot, all of them wiped out by floods. New Hampshire Historical Society records show that to cross Tasker and Fletcher’s bridge, initially, at least, foot passengers paid a toll of two cents, a horse and rider paid six cents, and “carts drawn by four beasts” paid the highest toll of twenty-five cents. Soon the proprietors raised the tolls; during the first five years, the bridge brought in $7,171, with a gross profit of $5,879. The state of New Hampshire purchased the bridge in 1935 and continued to operate it as a toll bridge until 1943, when the toll was eliminated. I think the most important decision that was made was to restore this bridge, to strengthen this bridge and in doing so strengthen this wonderful tradition of craftsmanship, of beauty, of what New England is all about.
VERMONT GOVERNOR MADELEINE M. KUNIN, AT THE REOPENING OF THE CORNISH-WINDSOR COVERED BRIDGE MAP, 1989
The structure, a Town lattice truss, is named for its inventor, Ithiel Town (see here). Town’s 1820 framing design consisted of two layers of planks, angled to form a lattice, an overlapping triangular configuration that distributed loads and, crucial for long spans, imparted a high degree of stiffness, or rigidity. Most important, Town trusses could be built cheaply by unskilled labor. Town trusses were used well into the twentieth century.
CORNISH-WINDSOR COVERED BRIDGE MAP LONGEST COVERED BRIDGE MAP IN THE UNITED STATES Photo Gallery
Timber bridges were once common in New England, an area rich with forests and sawmills. Wood was and still is considered a particularly good material for bridge building because it gives evidence of distress long before failing. In this case, a 1908 report indicates the bridge had a 9-inch (23-centimeter) sag that had increased by 1986, when 2,500 cars crossed daily, to 17 inches (43 centimeters). Yet the bridge continued to be used. An elevation shows the Cornish-Windsor’s mortared stone pier and abutments, and eighteen of its thirty-six windows. Its total length is 450 feet (137 meters) with two clear spans of 204 feet (62.2 meters) and 203 feet (61.9 meters). The interior roadway is nearly 20 feet (6 meters) wide, with a vertical clearance of just under 13 feet (4 meters).
In 1812 Lewis Wernwag, a German immigrant, built a second span across the Schuylkill. With a span of 340 feet (104 meters), it was known as the Colossus at Philadelphia. Called a “wonder of the world” because of its remarkable length, the bridge was immortalized in numerous engravings such as this one.
Repairs were needed, but they were delayed by debates about the restoration process. Using timber to restore the bridge to nineteenth-century standards, while historically authentic, would alter its picturesque exterior. Many, including the National Society for the Preservation of Covered Bridges, objected to the transit authorities’ decision to repair it using modern materials. Although a compromise, it preserved the bridge’s historic appearance and met modern highway load ratings, allowing it to remain in service. Work began in 1988 and the bridge reopened a year later.
The Cornish-Windsor is one of the few surviving covered wooden bridges in America. The first covered bridge, the so-called Permanent Bridge over the Schuylkill River in Philadelphia, opened in 1805. The 550-foot (168-meter) span is credited to Timothy Palmer of Newburyport, Massachusetts. His original design didn’t have a roof, but he was encouraged to add one; covered, a bridge could last as long as thirty to forty years, three times longer than one without a roof. After the Permanent Bridge opened, it stood for forty-five years, and covered bridges became the rule, not the exception.
The Bollman Truss Railroad Bridge (1869), on an abandoned spur of the Baltimore and Ohio Railroad in Savage, Maryland, is the sole surviving example of the suspension and truss hybrid Wendel Bollman invented in 1850.