Curtis Mill Road and P and D. R.R. Baltimore and Ohio Railroad Company. Philadelphia Division. Railroad bridges -- Delaware. Truss bridges -- Delaware. Depicts a railroad bridge with both a deck plate girder and through truss design. March 1891. Cyanotypes 1890-1900 digitool:36612 Library Company of Philadelphia Print Dept. albums - B&O [P.9945.57] P.9945.57 Part of B & O Railroad Album Part of B & O Railroad Album: "Bridges and buildings, Philadelphia Division, Baltimore & Ohio Railroad, 1891."