The gravel track down the street has been my good friend during the quarantine. My days are much happier and productive if I start with a quick walk to and from the track and a few laps in the morning air.
When I'm running on the track, keeping my head up and my eyes looking out, I see lines of lighter gravel clearly marking several jogging lanes. Although these lines are smeared and messy—it would be tough to find a definitive start and end to a given line—the division between lanes is surely visible.
But when I looked down directly below me in a section of the line as small as a square foot, the lighter stones and darker s...