When you look at the bridge, it should become rather clear that something happened. Clearly one of these spans was not originally erected here. The two completely different truss spans does give some signal of an accident, or a disaster. Just makes one wonder...
Thank you Douglas, I will add the photograph and the historical information.
I posted a photo of this bridge on Wikimedia Commons (to illustrate the Wikipedia entry for lattice truss bridge). The URL is:
Further details about this bridge: This was originally the mainline of the Iowa City and Western Railroad, later the Iowa City division of the Burlington Cedar Rapids and Northern Railroad and then a minor branch of the Chicago, Rock Island and Pacific Railroad before the CRANDIC took over the line.
The east approach to this bridge crosses the Iowa River floodway on a wooden trestle, I also photographed this and put it on the commons:
I put these photos in the public domain (see the Wikimedia Commons copyright notices) so if anyone thinks copies should be placed in the Bridgehunter database, they're free to do so.
The Lattice truss looks like a possible M. Lassig product. The laced diagonals and pedimented portal bracing both indicate this. I am not seeing the porforated knee bracing, but this could have been removed at some point.
Luke, It looks like a Warren from what I can see. The verticals in each panel may be as much for supporting the floor beams than part of the truss.
Tony or someone should figure out what truss type the other span is, because I honestly have no clue other than it's CLEARLY a truss.