When you look at one of the world’s great rivers on a map, you assume that the path it cuts through the land is fixed. But rivers like the Mississippi actually change course quite dramatically over time thanks to flooding and other factors. In 1944, a cartographer named Harold N. Fisk commissioned an epic study of the Lower Mississippi River, charting its ebbs and flows over time. His maps sandwich color-coded layers (each one depicting a distinct path the river took at one point in time) on top of each other, providing ecologists and planners with a distinct view of each flood path but also a gestalt visualization of the mighty river’s swath through the landscape. It’s part Edward Tufte, part Jackson Pollock.
The idea of superimposing distinct visualizations of one phenomenon on top of each other seems more appropriate to our digital, Photoshop-enhanced age than the world of 1944, in which every one of Fisk’s ultradetailed studies had to be drawn by hand. (You can download them all in high resolution by clicking here.)
In fact, seeing these images makes me wish some industrious map-loving designer would take Fisk’s raw material and rework it into an interactive display, so that the lovingly hand-colored layers could be controlled and manipulated at will to reveal the subtle narratives embedded in the drawings. That’s not to say that an eagle-eyed viewer can’t discern those narratives for themselves just from Fisk’s originals, of course. And even those of us who don’t know a whit about Northern American seasonal topography can appreciate these stunning visualizations as fine art in and of themselves. Either way, Fisk’s maps can rightly stand with Charles Minard’s chart of Napoleon’s doomed Russian campaign as infographics for the ages.