By the time I took my after-dinner walk it was almost 9 p.m. The light had faded from the sky, and clouds obscured the moon and stars. A head lamp turned me into a roving Cyclops; I was alone in a bright, clammy tunnel. No music, no sunshine, the air heavy with the moisture of an impending shower.

 Don’t look at the cars or you’ll blind the drivers, Tom said, instructing me on the headlamp as I walked out the garage door. So I turned my head demurely whenever a car passed. This had the additional benefit of obscuring my identity. I didn’t need my teenager to tell me how dorky I looked (though she was glad to point it out). I knew that a headlamp and a day-glow safety vest would not  win me any beauty prizes.

But the outfit — and the effort — were worth it. They made it possible to walk in the dark, to prolong the day, to pretend, just for a moment, that it was a sultry June evening — instead of a stifling September one.