WILLIAMSPORT, Md. (AP) You won’t find a mule named Sal in the exhibit, “Building America’s Canals.’’
This is a nuts-and-bolts affair that presents families with some of the same engineering challenges the nation’s founders faced during America’s westward expansion. Visitors can construct and operate miniature cranes, locks and aqueducts, and even analyze the costs of various canal systems.
Just because mule-drawn canal boats gave way to motorized barges 90 years ago, don’t imagine there’s nothing relevant to be learned from the traveling exhibit, which is at the Chesapeake and Ohio Canal National Historical Park’s Trolly Barn in Williamsport through Oct. 12.
“That same science, that same harnessing of physics, went into a lot of the things you see today — highways, bridges, buildings — and this is really the start of that in America,’’ said Edward Mooney, director of exhibits at the National Canal Museum in Easton, Pa.
That museum created the exhibit more than two years ago, and has sent it out on a tour that began in January at the Discovery Center in Murfreesboro, Tenn. The next stop is the Western Reserve Historical Society History Museum in Cleveland, followed by an engagement at the Works Museum in Newark, Ohio.
The 1,600-sq.-ft. exhibit includes five colorful activity stations. But children entering through the 11-foot-high wooden lock gates will probably rush to the large, low table that is the centerpiece of the display. The tabletop, 15 ft. long and 4.5 ft. wide, is a green landscape of farms, towns and forests with a coal mine at one end and a city at the other, connected by a winding blue river.
Visitors are invited to build a canal to move coal from the mine to the city along any of a half-dozen proposed routes. The catch is the cost: There is a dollar value attached to each six-inch canal segment, ranging from $100,000 for a simple length of trough to $1 million for a tunnel. Locks and aqueducts are available for getting past the steep drops that hinder river navigation.
Piecing together a route, one might agree with the late historian Ronald E. Shaw, who wrote in his book, “Canals for a Nation,’’ that “American canals were audacious achievements of engineering and construction, often in nearly impossible terrain.’’
Shaw’s book describes about 40 canals built from 1785 to 1860 in a region stretching from Maine to Illinois and as far south as North Carolina.
Aqueducts — elevated troughs that carry canal boats over obstacles such as rivers and gorges — get a lot of exposure in the exhibit, reflecting their importance in canal construction and American architecture. One station allows visitors to build a suspension-bridge aqueduct like the Allegheny Aqueduct that John A. Roebling designed for the Main Line Canal in Pittsburgh in 1845. It was the first suspension aqueduct in the United States and it led to greater things for Roebling; he went on to design the Brooklyn Bridge.
Another type of aqueduct, made of masonry instead of cables and planks, lets visitors experience the enduring strength of arches. Stone by trapezoidal stone, one constructs a two-arch aqueduct, removes the semicircular supports and marvels as the ancient design not only refuses to collapse but practically begs for the weight of a cargo-laden canal boat.
Once visitors understand the structure, they can step outside and see the real thing. The Conococheague (pronounced kah-nah-kah-CHEEG) Aqueduct, one of 11 along the C&O Canal, spans the mouth of Conococheague Creek. It is in need of repair, which will likely require financial support from both private and public sources.
Park managers and the C&O Canal Trust, a nonprofit partner group that helped sponsor the exhibit, hope it will teach more people to appreciate the complexity of building and maintaining the canal even as they hike and bike the 185-mi. towpath once used by mules pulling boats between Cumberland and Washington, D.C.
“These canals were like the interstate highways of the 19th century,’’ said William Justice, the park’s chief of interpretive services. “It’s impressive, seeing a whole bunch of kids learn about the history of canals.’’