(via Gemmology Queensland, Vol.4, No.11, November 2003 / IIS Newsletter 80/2003)
Apparently no visual instruments existed at the time of the ancient Egyptians, Greeks, or Romans. At least this view is supported by a letter written by a prominent Roman about 100 B.C in which he stressed his resignation to old age and his complaint that he could no longer read for himself, having instead to rely on his slaves. The Roman tragedian Seneca, born in about 4 B.C is alleged to have read all the books in Rome by peering at them through a glass globe of water to produce magnification. Nero used an emerald held up to his eye while he watched gladiators fight. This is not proof that the Romans had any idea about lenses, since it is likely that Nero used the emerald because of its green color, which filtered the sunlight. Ptolemy mentions the general principle of magnification; but the lenses then available were unsuitable for use in precise magnification.
The oldest known lens was found in the ruins of ancient Nineveh and was made of polished rock crystal, an inch and one-half in diameter. Aristophanes in ‘The Clouds’ refers to a glass for burning holes in parchment and also mentions the use of burning glasses for erasing writing from wax tablets. According to Pliny, physicians used them for cauterizing wounds. Around 1000 A.D the reading stone, what we know as a magnifying glass, was developed. It was a segment of a glass sphere that could be laid against reading material to magnify the letters. It enables presbyopic (short sighted) monks to read and was probably the first reading aid.
The Venetians learned how to produce glass for reading ‘stones’, and later they constructed lenses that could be held in a frame in front of the eyes instead of directly on the reading material. Spectacles as we know them, were invented some 700 hundred years ago, presumably in Northern Italy. The oldest complete specimens date from sometime around 1350 and were found in the excavation of a nunnery near Celle in Germany. The first glasses were made out of beryl, a semi-precious stone, from which glasses obtained their name in Germanic languages, where they are called bril or brille.
The first known artistic representation of eyeglasses was painted by Tommaso da Modena in 1352. He did a series of frescoes of brothers busily reading or copying manuscripts. One holds a magnifying glass, but another has glasses perched on his nose. Once Tommaso had established the precedent, other painters placed spectacles on the noses of all sorts of subjects, probably as a symbol of wisdom and respect.
The first spectacles had quartz lenses because optical glass had not been developed. The lenses were set into bone, metal or even leather mountings, often shaped like two small magnifying glasses with handles riveted together typically in an inverted V shape that could be balanced on the bridge of the nose. The use of spectacles spread from Italy to the Low Countries, Germany, Spain, and France. In England, a Spectacle Makers Company was formed in 1629; its coat of arms showed three pairs of spectacles and a motto: ‘A blessing to the aged’.
Benjamin Franklin in the 1780’s developed the bifocal. Later he wrote, “I therefore had formerly two pairs of spectacles, which I shifted occasionally, as in traveling I sometimes read, and often wanted to regard the prospects. Finding this change troublesome, and not always sufficiently ready, I had the glasses cut and a half of each kind associated in the same circle. By this means, as I wear my own spectacles constantly, I have only to move my eyes by or down, as I want to see distinctly far or near, the proper glasses being always ready.” Modern eyeglass frames can be made of almost any material, including ivory, tortoiseshell, wood, metal, and plastic.
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