A LITTLE GIRL in a puffy pink coat skipped along the grimy sidewalk under the dead gray morning sky, as withered leaves scuttled by her feet. The hoodie and the parka came off their separate hangers to be reunited as a necessary set of layers. The clouds opened out to a sky of blue and feathery white, with dull yellow-gray where the low sun made its way across the south. Squirrel nests stood out lumpily in a bare tree. A black dog in a vest capered with a long stick in its mouth. The cold stung the ears, but the puddles were still liquid. Each end of one crosstown block had a virus-testing station at it, and the lines stretched toward each other till they overlapped. The surgical mask stayed on between errands, as a welcome piece of insulation; if it came off, the condensation inside it became disgustingly clammy. The sun weakened and the chill rose as the only tree vendors in sight tried to drive their hardest bargains. Eight or nine blocks further uptown, though, the trees cost about half as much, and the daylight endured.