http://66.213.124.233/files/original/673a07de1a07818e5145b017da8c5613.jpg 322490ad138926b73fdd1393a597441e Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Description An account of the resource Unique Covered Bridge in Delaware County By David A. Simmons Ohio Historical Society How do specific bridge designs be- come popular? During the nineteenth century, much as today, promotional literature and sales personnel were important influences in encouraging contractors and public officials to use a specific design or product. The Chambers Road Covered Bridge, Del- aware County's only remaining wood- en truss, owes its design to neither and may, in fact, be unique for its role in the history of Ohio bridge con- struction. The builder of the Chambers Road bridge was Everett S. Sherman, who was born in 1831 to a bridge-building family in Delaware County. The two- story frame house built for his father, David T. Sherman, still stands in the tiny community of Berkshire, where recent renovations uncovered the massive framing -enormous even by nineteenth-century standards-of a rear wing built in the mid 1850's. Like modern contractors, the Shermans had incorporated leftover bridge ma- terials into their new residential addi- tion. The first known work to have been done by Everett Sherman alone was the erection of a bridge at Sunbury in 1867. The Howe truss system, whose heavy wooden diago- nals and vertical iron rods were a familiar sight on American railroads in the middle of the century, was used by Sherman in the 1870's. After mov- ing to a farm on the outskirts of Galena in the early 1870's, he re- ceived a patent for a simple bridge intended for small stream crossings on rural highways, It incorporated wooden beams and iron rods, a struc- tural type known at the time as "a combination bridge." [photo: Delaware County's last covered bridge, the Chambers Road Cov- ered Bridge, was built in 1883 and named for the nearby Chambers family homestead seen here in the right rear.] The Chambers Road Covered Bridge combines wood and iron in a system patented in 1846 by Horace Childs, a prominent New Hampshire railroad bridge builder. A Childs truss had diagonal wooden braces in com- pression that were crossed by diago- nal iron rods, or "counterbraces." Nuts on these rods held the braces against the top and bottom chords- a vital maintenance consideration with wooden structures susceptible to shrinkage - and could also be tight- ened to add camber to the structure. [photo: Based on a rare patent devised in 1846 by a new England railroad bridge builder, the Chambers Road bridge has wooden diagonal members in compression which are crossed by iron rod tension members.] [photo: Delaware County forces, under the direction of County engineer Fred Stults, renovated the bridge in time for its one-hundredth birthday. New concrete abutments and a concrete pier were in- stalled to support a group of concealed steel I-beams that actually carry the loads across Big Walnut Creek. New siding and roof were were also added to protect the old historic trusses.] Historians have long puzzled over Sherman's use of the Childs truss in the late nineteenth century when it was already an antiquated structural system that apparently never saw much use even by its own New En- gland designer. Assumptions were made, now known to have been wrong, that Sherman,like Childs, was a native of New Hampshire and must have learned of this obscure truss from the older builder himself. The real reason, I believe, is much simpler: Sherman had read about it. In October 1882, a Washington, D.C. patent attorney began a series of illus- trated articles in Engineering News on truss bridge patents whose period of protection had elapsed, and which Title A name given to the resource Unique Covered Bridge in Delaware County (p. 1) Publisher An entity responsible for making the resource available Ohio County Engineers News http://66.213.124.233/files/original/0bb1382d83502745c5e2054fd03ddcfd.jpg a4e3eaeede720b9330d74a397aaed417 Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Description An account of the resource Unique Covered Bridge (Continued from Page 10) were then "public property." The twenty-nine part series began with Theodore Burr's 1817 patent and ended with a suspension truss dating to 1866 whose patent expired in De- cember 1883. The December 16, 1882, installment included a descrip- tion and drawing of the "Childs Bridge." Sherman, already conversant in the use of wooden and iron con- struction, apparently read the article and resolved to try the system with his next bridge contract. The Chambers Road Covered Bridge, using an ex- pired patent for which no royalties were owed, was built by Sherman the following year. Sherman did more than simply re- vive a defunct bridge truss; he im- proved it. In 1886 he moved to Eaton at the invitation of the Preble County Engineer, who was also a native of Delaware County, to assist in rebuild- ing the bridges recently destroyed in a "cyclone." The Childs design came from the empirical age of craftsman who built without the benefit of scien- tific truss analysis, and the original specifications called for braces of uni- form size. Sherman's Preble County bridges (only six of his original fifteen remain) were built with diagonal com- pression members, the dimensions of which increased toward the ends of the truss to accommodate the greater load carried by each-evidence of Sherman's efforts to mathematically proportion the components of his bridges. No other Childs trusses are known to have been built anywhere in the nation except for Sherman's Ohio bridges. The Chambers Road Cov- ered Bridge, representing Sherman's initial use of the Childs truss and closely following the original design features, is thus an important trend- setter in Ohio and national engineer- ing history. The author would like to acknowledge his debt to the research on Sherman done by Miriam Wood, historian of the Southern Ohio Covered Bridge Association. Title A name given to the resource Unique Covered Bridge in Delaware County (p. 2) Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Porter Township Description An account of the resource The Porter Township Collection contains the Unique Covered Bridge in Delaware County, an article written by David Simmons about the Chambers Road Bridge, a video of the Porter Township School, photographs of historic homes including the birthplace of famous aviator Foster Lane. Text A resource consisting primarily of words for reading. Examples include books, letters, dissertations, poems, newspapers, articles, archives of mailing lists. Note that facsimiles or images of texts are still of the genre Text. Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Unique Covered Bridge in Delaware County Description An account of the resource This article describes the construction method used by Berkshire resident Everett Sherman, builder of the Chambers Road bridge in Porter Township. Publisher An entity responsible for making the resource available Ohio County Engineer Number 1 Spring 1991 Date A point or period of time associated with an event in the lifecycle of the resource 1991 Type The nature or genre of the resource Still Image Text Format The file format, physical medium, or dimensions of the resource Magazine article Identifier An unambiguous reference to the resource within a given context 92961004 Language A language of the resource English Creator An entity primarily responsible for making the resource Author David A. Simmons; Ohio Historical Society Rights Information about rights held in and over the resource http://rightsstatements.org/vocab/NoC-US/1.0/ Subject The topic of the resource Bridges--Construction--Delaware County--Ohio History--Berkshire Township--Delaware County--Ohio Porter Township--19th century--History Contributor An entity responsible for making contributions to the resource Miriam Wood, historian of the Southern Ohio Covered Bridge Association.