Eyeglasses and Concave Lenses in Fifteenth-Century Florence and Milan: New Documents*
Five recently discovered documents reveal for the first time that eyeglasses with concave lenses for myopes were manufactured in Florence from at least the middle of the fifteenth century, about one hundred years before they were thought to be in use. This new evidence throws additional light on the development and early use of spectacles and on the early history of optical instruments and glass technology in general. These documents also reveal for the first time that Florence was the leading manufacturing center of high-quality eyeglasses and that spectacles had already become a prestigious item of personal adornment at least at the court of the dukes of Milan. This information should be of interest to historians of art and costume as well.