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      The longest of three remaining bridges in Sullivan County, Pennsylvania, the 186-foot-long Hillsgrove Bridge was built around 1850 by Sadler Rodgers of nearby Forksville. This splendid Burr truss span was nearly lost when floods caused by Tropical Storm Lee’s 12 inches of rain in September 2011 caused a house to strike the bridge, requiring extensive renovation. As work progresses, visitors can better see the exposed trusses. (A. Chester Ong, 2012)

      UTILITARIAN CROSSINGS FOR A NEW CONTINENT

      Although they are commonly called “covered bridges,” the essence of such bridges is what lies beneath and is protected by the roofing and siding. The full name would more accurately be “covered wooden trussed bridges” because the last two elements—the trusses and their material, wood—are essential. While the enveloping roof and siding are critical to the survival of a trussed wooden bridge, they no more define it than our own skin, also critical to our survival, defines us as a human being. Consequently, in order to pursue a full understanding of covered bridge history and development in the United States and Canada, it is necessary to consider all wooden bridges, whether covered, uncovered, partially covered, or even those blending wood and iron.

      Covered bridges as defined above are not unique to North America. Historically speaking, the covered bridges of central Europe and southern China have much longer histories than those considered here, but the North American (hereafter “American”) covered bridge appears not only to have developed independently of these older traditions but along a radically different path.

      What makes this so is not the phenomenon of having covers but the nature of the wooden trusses that supported the bridges. Indeed, Chinese covered bridges (langqiao, meaning “corridor bridge”) have no trusses in the conventional sense, their support being provided beneath the deck and built to accommodate only pedestrians, animals, and small carts (Knapp, 2008). European bridges appear to have originated during medieval times, only developing into vehicular bridges after several hundred years. Their truss systems are mostly unlike those that were developed in the United States. From the beginning, American covered bridges, on the other hand, were intended for vehicular traffic such as wagons, as well as for pedestrians and animals, yet in time they came to include use by even railroad trains and canal boats. Several European countries are known to have built wooden rail bridges but mostly under American influence, while China never had covered bridges carrying trains or boats. While wooden truss bridges, covered or uncovered, did not originate in the United States, the designs that emerged of such bridges were uniquely American.

      Luzerne, Switzerland’s Spreuerbrücke, spanning the River Reuss, although built in 1566 by Kaspar Meglinger, exemplifies the Medieval bridge technology of Germany, Austria, and Switzerland. Besides having a chapel midstream, there is a series of sixty-seven paintings under the roof painted between 1626 and 1635 depicting “The Dance of Death.” (Terry E. Miller, 1974)

      Spanning the River Ilm in the village of Buchfart, Thuringia, Germany, this two-span bridge was built around the year 1817. Each span uses a queenpost truss with a clear span of 53 feet of a total of 123 feet. (Philip C. S. Caston, 2004)

      Unidentified Austrian bridge with castle above as photographed from a moving train by the co-author’s father. (Max T. Miller, 1980)

      The Santiao Bridge in Taishun County, Zhejiang Province, People’s Republic of China, straddles a rock-strewn chasm. It was built in 1843 on the site of nearby older bridges that helped link the stone-lined footpaths in this remote area. (A. Chester Ong, 2007)

      Seen from beneath, the Santiao Bridge is lifted by major and minor timbers that are woven together to raise the structure some 10 meters above the streambed. (A. Chester Ong, 2007)

      It is commonplace to describe “the past” as simple, uncluttered, and stress-free. We are inclined to idealize the eighteenth and nineteenth centuries as slower paced and more personal, and believe that the absence of distractions such as telephones, audio systems, computers, and traffic congestion made life more relaxing and peaceful. The European immigrants who arrived at various places on the eastern coast of North America in ever greater numbers during the seventeenth century were confronted with a relatively pristine natural environment but had enormous challenges ahead of them. Except for Indian trails, there were no roads through the vast forests or over the mountains. Even in 1837, when English civil engineer David Stevenson traveled throughout the eastern United States and published his Sketch of the Civil Engineering of North America, the American road system was deplorable. Writes Stevenson: “Road-making is a branch of engineering which has been very little cultivated in America, . . . direct[ing] their whole attention to the construction of canals, as being much better adapted to supply their wants.” And also: “The roads throughout the United States and Canada, are, from these causes not very numerous, and most of those by which I travelled were in so neglected and wretched a condition, as hardly to deserve the name of highways, being quite unfit for any vehicle but an American stage, and any pilot but an American driver. In many parts of the country, the operation of cutting a track through the forests of a sufficient

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