In 2001, historian Roger Ekirch of Virginia Tech published a seminal paper, drawn from 16 years of research, revealing a wealth of historical evidence that humans used to sleep in two distinct chunks.
Ekirch says this 1595 engraving by Jan Saenredam is evidence of activity at night
His book At Day’s Close: Night in Times Past, published four years later, unearths more than 500 references to a segmented sleeping pattern - in diaries, court records, medical books and literature, from Homer’s Odyssey to an anthropological account of modern tribes in Nigeria.
Much like the experience of Wehr’s subjects, these references describe a first sleep which began about two hours after dusk, followed by waking period of one or two hours and then a second sleep.
“It’s not just the number of references - it is the way they refer to it, as if it was common knowledge,” Ekirch says.
Just thought I would share that so many threads “lows in the middle of the night” Well its OK to be up in the middle of the night ! Its normal.