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burn holes in parchment, while Pliny the physician used a lens to cauterize wounds.
• A thousand years later monks started using "reading stones", which were sliced off sections of polished quartz spheres, and sometime in the later half of the 1200s the monks put these reading stones up on their noses and called them spectacles.
• It is no surprise that it was in Venice, Italy where glassmaking was (and still is) an art, that convex reading or magnifying glasses were refined.
• About three hundred years later, concave lenses were found to help the near-sighted Pope Leo the 10th, who wore such spectacles to aid him while hunting. It took just about three hundred more years for bifocals to be invented by America's own Benjamin Franklin.
• It was in the mid 1800s that a protective lens was made that fit directly over the eyeball of a man who had lost his eyelid from skin cancer. This first "contact lens" protected his eye from drying out and resulting blindness.
• Over the next 150 years contact lenses came into commercial use and moved from blown, to ground, to molded glass, and then to a whole variety of hard then soft plastic lenses.
• And now the knowledge of refracting light with lenses has brought us to computer
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