I have posted photos from some of the Forgotten Chicago tours of the industrial Calumet River area of the lift bridges that, when the track is down, span the river, but are kept well above the height that freighters need to maintain clearance and keep the river traffic moving.

It’s hard to reduce the scale of those bridges, which are immense, to a little photo on a little blog. On my last of those trips, I was happy to see this view of one of the wheels that actually moves all of that metal. Even these wheels — essentially the pulleys that move much of the mechanism — are staggeringly large. They have counterparts atop the structures and at some point, I’ll post one of those, which will lose the sense of scale we see here but show how it all fits together.

July 21, 2013. Nikon D7100 (DX sensor), Nikon 70–300mm lens at 70mm (35mm equivalent: 105mm), f/4.5, 1/8,000, ISO 1,250.