Landes :Eyeglasses:

Landes argues that the invention of spectacles in Europe not only made it possible for craftsmen to work longer, it also Doubled the working life of skilled scribes (crucial before the invention of printing) and readers, instrument and toolmakers, close weavers, metal workers. Eyeglasses pushed The Europeans to invent gauges, micrometers, fine wheel cutters—a battery of tools linked to precision measurement and control. Thie skill of creating eyeglasses made Europe a leader in replication—batch and then mass production. moreover, was a school for further optical advances that made the invention of telescopes and microscopes possible. the invention of spectacles in Europe not only made it possible for craftsmen to work longer, it also doubled the skilled craft workforce

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