Sleeping in two distinct blocks opens an ancient portal to the other side of midnight, reports The New York Times.
Soon insomnia knocked me totally out of sync, and I compensated one night by nodding off at 8 p.m. That caused me to wake up at 2 a.m., disoriented. I spent a few hours brooding, then slept again until 6, when I got up, had coffee and showered. Tired again at 8 p.m., I repeated the pattern the following night. And the next, and the next, until I was regularly entering the forgotten, ancient tunnel to the other side of midnight: segmented sleep. It looked embarrassing in a modern context, but it was once the most normal thing in the world.