There’s an idea out there that humans, entirely naturally, have two sleep segments in a night. Go to bed, sleep a bit, wake up, potter about, go back to sleep. The originator talking about someone who doubts it:
In the winter, whether for conviviality or work, preindustrial households remained active well after sunset, not retiring until 21:00 or 22:00, or later when visiting with neighbors. People relied on primitive illuminants, such as rushlights and oil lamps, or on the natural light of the moon and stars on clear nights, even to perform unskilled chores such as chopping firewood.3
Second, it is clear that biphasic sleep was not unique to Western households. Instead, it occurred well beyond the bounds of Europe and North America in other cultures and continents, including the Middle East, Africa, South Asia, Southeast Asia, Australia, and Latin America, thereby heightening the likelihood that throughout the preindustrial world this form of sleep was not at all uncommon, including in equatorial cultures.
Chopping wood by bad light? Is ‘e ‘avin a giraffe?
The point doesn’t make economic sense to be honest. Given the vast expense of artificial light back then it doesn’t make sense that is.
So, the task is to try to work out what has been misundertood to create this supposition.
I once spent weeks tracking down something that was all over the place. Britannica, varied books on rare earths, other encyclopaedias. Scandium sulfate – ScSO4 – was, apparently, used in germinating seeds. And yet while I could find this in every reference book I could find anyone in seed germination who knew anything about it – I was trying to sell scandium at the time.
Eventually I found a bloke who purified a bit of scandium on the side. And who also made additives to go into fertilisers etc. Just happened to be his thing. One of the things he made being seleno-urea. Which is an addition of selenium to a fertiliser to be used in soils lacking in the selenium necessary to aid seeds in germinating…..
That’s SeSO4. And it doesn’t take all that much imagination to see that SeSO4 might have been scribbled down once as ScSO4. If textbook entries were then copied from each other…..
As it happened at around this time I also met someone who had written on of the textbook guides to rare earths. A journo he was. Who happily admitted that the way to write such was to get the last five such books in a pile, fillet and rewrite.
The idea that scandium was used in seed germination was a scribe’s error.
We have something similar in Juliet Schor’s insistence that medieval peasants had more leisure time than we do today. Look, they had 70 Holy Days, a Holy Day is where we derive holiday from, that’s 70 days off a year!
Yeah, bollocks ‘n’ all. They were animal owning peasants. Animal owners who take 70 days off a year don’t get to keep owning animals. A Holy Day not, in fact, being a day upon which no work was done.
Do, this idea of segmented sleeping?
Well, who were the only literates in these medieval times? Largely speaking – not exactly, but usefully – the clergy. And it wasn’t the parish clergy either, it was the monks.
The monks who did have segmented sleep as Matins was 2 hours after midnight, after which there was another 3 hour sleepy byes until Lauds.
The written evidence we have is from that part of society which did have segmented sleep. But to project segmented sleep out over the population as a whole might well be an error.
I don’t insist this is true, even as I insist there’s something fishy about the very idea of segmented sleep given illumination costs. And, to be honest, given how grumpy I think all we moderns would be if we did that segmented bit.
However, it would be fascinating for someone to dig down into his information and see how much of it is in fact a description of monastic life rather than general.