2023-04-24 05:00:00
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It is difficult today to imagine a world without glasses. Whether they are simply suitable for reading or whether they constantly help a myopic person in distress in the face of his environment, they are essential to many of us and are part of everyday life. To the point of asking: how did we do it before?
The arrival of this precious tool in our lives is actually relatively recent. The democratization of glasses only happened a handful of centuries ago. Before, well, we did without. Or, even stranger, we dreamed… of being nearsighted.
Myopic at all costs
In history, it would seem that myopia has not always occupied such an important place in everyday life as it does today. And for good reason: this type of sight problem was much less common.
If she probably always existed – even with our distant ancestors primates–, the number of people affected has increased sharply over the past three centuries, rapporte Live Science. Worse, on the scale of a few decades, it exploded. Scientists thus estimated in 2016 that half the world will be myopic by 2050. In some Asian countries, the figures are already impressive: in Seoul, for example, some 95% of 19-year-old men are now myopic.
How to explain this strange phenomenon? Although scientists are still racking their brains to answer this puzzle, some hypotheses are emerging. Some point to genetic causes, others to increased study and screen time. The explanation could even come from our way of life, more and more between four walls. Researchers have found that children who spend less time outdoors were more likely to develop myopia. Living in dim light wouldn’t help our eyesight.
That’s all well and good, but it doesn’t answer our question. How did myopes do before the invention of glasses? Less numerous than today, they were far from being a priority and made do with their failure, as best they could. Some of them have even ended up adapting, to the point that we began to envy them this problem of sight.
Being short-sighted was the invaluable asset of certain medieval craftsmen, especially at manuscript illuminators. If their vision from afar was like that of a drunk coming out of a tavern, their vision up close was formidable. A precious characteristic that allowed them to handle with great meticulousness the brushes that came to decorate bibles and manuscripts. Some families therefore prayed that their newborn would be born myopic like a mole.
From reading stone to glasses
Today, not sure that there are enough Bibles to decorate for all the short-sighted people in France. Fortunately, glasses have come to revolutionize the way we see things. An invention that we owe in particular to the discoveries ofan Arab scholar and astronomer, Ibn al-Haytam.
The latter was the first, towards the end of the Xe and beginning of the XIe century, to suggest that smooth lenses and glass spheres for optical magnification could help a visually impaired person. A brilliant idea which unfortunately fell into oblivion, until its Treatise on optics was translated into Latin in 1240, and that Italian monks seized on his works.
In no time, they developed a “reading stone”: a semi-spherical lens in rock crystal and quartz which, when placed on a text, amplified the letters. We get closer, but are even closer to an imposing magnifying glass than discreet glasses that fit on the nose.
Short-sighted people will have to wait until the XVe century to see the first lenses suitable for sight on the market – although they remain particularly rare. Among the earliest depictions of hand-held concave lenses in Europe, we find in particular a portrait of Pope Leo Xfamous nearsighted painter painted by Raphael at the beginning of the XVIe century. The effect of the glass is painted in such a way that the experts concluded that it was indeed that of a lens dedicated to the use of a person with myopia.
The Portrait of Pope Leo X with his cousins, Cardinals Giulio de Medici and Luigi de Rossi, by Raphael (1518-1519). | Public domain via Wikimedia Commons
Reading will do the rest. Spectacles will gradually multiply on the noses of citizens with the explosion of literacy, until adopting, in the 1700s, the long branches that hold on the ears. The glasses were definitely born.
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