Tilton Island Bridge, New Hampshire
Although it is not a through-truss bridge, the 1881 Tilton Island Park Bridge in New Hampshire has ten cast-iron builder plaques used as joint covers on the railing, and these display the patent date of 1856. These plaques are heavily rusted, but all ten of them also, quite legibly, display the construction information in letters cast into the iron. The construction information clearly reads “A.D. BRIGG & CO. UILDERS.” Not “BUILDERS” but “UILDERS,” capturing what appears to be a major typographical error and still displaying it for posterity almost 150 years later.
I have posted a few photos of the bridge, including close-ups of the plaques, onto www.bridgespotting.com.