This visualization takes Minard's famous chart that shows many things about Napoleon's campaign to and from Moscow. We can see the number of troops left in the thickness of the path, the geographical route takes from the location of the path and for the return journey we can also find the temperature in the small line chart at the bottom. I adjusted this from the Wikipedia version to give it back its older feel, but mostly I added an animated gradient to make the direction of the troop movement a bit more intuitive. The brown section is moving towards Moscow, whereas the black path is moving away from Moscow
Other examples of animated gradients can be found here
Note that Safari cannot handle the spreadMethod reflect, thus the gradient looks a bit weird in Safari. Try looking at this in Chrome or Firefox
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