Mallaham Bridge, County Route M-6 spanning Riley Creek, Pandora, Putnam County, OH
Significance: The bridge is an example of "Morrison's Patent Wrought Iron Arch Truss Bridge," based on a patent granted David H. Morrison in 1867. Unique among bowstring arches, this design used vertically-oriented I-beam flanges to form the bow. Morrison, founder of the Columbia Bridge Works of Dayton, Ohio, was one of the most important bridge engineers and manufacturers in 19th century Ohio.
Unprocessed Field note material exists for this structure: N38
Survey number: HAER OH-88
Building/structure dates: 1876 Initial Construction