One of several things I learned on Saturday's trip on the Mississippi: just how big can the barge flotillas be and how much they can carry. The overall size is limited by the size of the locks. Each barge is a standard size. The locks can hold three across and five long, plus the push boat. We were told that the whole assembly can hold the equivalent of 900 US truck trailers. It's mostly fungible stuff, usually coal or grain. As we were disembarking, we saw one go by with 18 of the enormous fan blades used in new-style wind generators.
The light was terribly dull so I decided that B&W was the lesser of two evils. There are some shots that came out well in eerie, muted color.