December 5, 2013

I THINK ANN ALTHOUSE HAS WRITTEN ABOUT THIS: How Our Ancestors Used To Sleep Twice A Night. “We used to sleep in two shorter periods, over a longer range of night. This range was about 12 hours long, and began with a sleep of three to four hours, wakefulness of two to three hours, then sleep again until morning.”

UPDATE: Ah, Althouse’s posts are here and here.