Keep Watch

According to a sleep researcher, historically, humans naturally slept during the night in two shifts with a time of wakefulness for one to three hours. “The period of wakefulness that followed was known as ‘the watch’—and it was a surprisingly useful window in which to get things done. ‘[The records] describe how people did just about anything and everything after they awakened from their first sleep,’ says Ekirch. … For peasants, waking up meant getting back down to more serious work—whether...