Dark Was The Night: Sleep

For about 10 years, I’ve wanted to write — or at least read — a good nonfiction book about Night. According to a review in the New Yorker (which seems to take all my best ideas), it looks like I’ve got my chance — “At Day’s Close: Night in Times Past” by A. Roger Ekirch has just been published by Norton.

As I’ve written before, for most of human history, Night was dark. On a moonless night, you couldn’t see your hand in front of your face or where your feet were stepping. In the largest capital cities in the world, the buildings around you appeared as little more than silhouettes against the stars of the Milky Way. (That is, Night in the past is something you need to research if you want to understand it.) If and when I read Ekirch’s book, I’ll tell you more, but the New Yorker focuses on Ekirch’s discussion of the “first and second sleeps,” mentioned by writers from Plutarch and Virgil all the way through John Locke.

Through artificial lighting, we’ve expanded Day to encroach on Night as far as we possibly can. When we finally turn off the light and go to sleep, we insist on sleeping continuously right through to the alarm.

But people — or at the very least, Western Europeans of a certain class — used to find themselves quite in the dark as soon as the sun went down. Any light had to come from an open flame of some sort. So they would go to bed, enjoying several hours of good, deep, REM sleep, and then they’d wake up around midnight or so. This was the first sleep. After one to several hours, they’d experience the second sleep, which would take them to the rooster’s crow. Between the first and second sleeps, they’d get up and do chores, or talk, study, pray, reflect, or, one supposes, have sex.

The National Institute of Mental Health recently did a study in which it deprived subjects of artificial lighting for up to 14 hours for several weeks at a time. They found the subjects naturally gravitated toward a first and second sleep. The period between possessed “an endocrinology all its own,” with elevated levels of prolactin, best known for stimulating lactation in nursing mothers. The period between sleeps was peaceful, restful, and reflective — and the first sleep’s dreams still lingered at the edges of consciousness.

Ekirch writes, “By turning night into day, modern technology has helped to obstruct our oldest path to the human psyche.”