Two for the Price of One

Bifocals described

May 23, 1785: Benjamin Franklin writes a letter claiming he invented double lenses spectacles. Our ancient ancestors had to cope with poor of failing eyesight as there were no corrective measures available to them. Seneca, born around 4 BC, read while looking through a globe of water to achieve some means of magnification. Nero watched gladiators while gazing through an emerald, not as magnifying lens, but as sunglasses.

The oldest lens found at Nineveh (see April 23) dated from about 600 BC but it was used to focus light for burning things. By 1000 AD, a reading stone or magnifying glass was invented. It was laid directly over print to work as a magnifying aid. Eventually the idea changed to two smaller framed lenses held in front of the eyes. The Chinese created paired lenses about 2,000 years ago, but these were used to protect the eyes from evil spirits and did not correct for vision.

In 1268, Roger Bacon described corrective lenses in Opus Majur and in 1289 di Popozo wrote about them and called them “spectacles.” While the first lenses were simply magnifiers, by the 16^th century concave lenses were made for correction of near-sightedness. It took over 300 years to correct one design flaw – keeping the lenses correctly positioned in front of the eyes. First they were placed in frames that were perched on the nose – pince-nez. Some noses were simply not up to the task. By the 17^th century, silk ribbons were tied to the frames and looped around the ears. In 1730 rigid side pieces were added and in 1752 they were finally hinged.

Contacts were first described in 1845 but none were tried until 1889. They were not very successful at that time. By the 1940s many varieties of contacts were available, most made of some form of glass. These could be tolerated only for short periods of time. With the introduction of plastic lenses and the further refinement of the product, by 1964 6 million Americans were wearing contacts.

“I wear my wife’s eyeglasses because she wants me to see things her way.” – Jayson Feinburg

“Rose-colored glasses are never made in bifocals. Nobody wants to read the small print in dreams.” – Ann Landers

“I had some eyeglasses. I was walking down the street when suddenly the prescription ran out.” – Stephen Wright

“Bifocals effectively work the same way they have since they were invented by Benjamin Franklin. But as any of more than 40 million people in America who need bifocals know, they’re a pain.” – Nasser Peyghambarian

Also on this day:
Patience and Fortitude – In 1911 the main Research Library of the New York Public Library is dedicated.
Aaagh, Pirates – In 1701, Captain Kidd was hanged for piracy.