-- Historic American Engineering Record
Given the location of this bridge, and the date of its construction, I strongly believe that "J. B. White" is a typo, and should refer to T. B. White and Sons of New Brighton, PA. This haer documentation http://lcweb2.loc.gov/master/pnp/habshaer/oh/oh1600/oh1600/d... for a different bridge noted that White did build timber bridges, and originally was a carpenter.