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Glasses Reference Libraries

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Sunglasses
2010-11-15 19:37:34

Sunglasses are protective eyewear designed to shield the eyes from damaging or discomforting sunlight and high-energy light. They can also work as a visual aid. The ultraviolet radiation from the sun can cause several serious eye problems and many healthcare professionals recommend eye protection. However, since the 1940s sunglasses have been associated with celebrities more so than eye...

Bifocals
2010-09-23 19:15:37

Bifocals are eyeglasses, commonly prescribed for presbyopia, with two distinct optical powers. Although there are arguments against him, Benjamin Franklin is generally credited with the invention of bifocals. After a correspondence between George Whatley and John Fenno it was thought that Franklin possibly invented the bifocals fifty years earlier than previously thought. Many inventions...

Magnifying Glass
2010-09-16 15:48:43

A magnifying glass is a convex lens, usually mounted in a frame with a handle, which is used to produce a magnified image of an object. The glass works by creating a magnified virtual image of an object behind the lens. However, the distance between the lens and the object must be shorter than the focal length for the glass to work. If the distance is not correct then the image will appear...

Word of the Day
vermicular
  • Like a worm in form or movement; vermiform; tortuous or sinuous; also, writhing or wriggling.
  • Like the track or trace of a worm; appearing as if worm-eaten; vermiculate.
  • Marked with fine, close-set, wavy or tortuous lines of color; vermiculated.
  • A form of rusticated masonry which is so wrought as to appear thickly indented with worm-tracks.
This word ultimately comes from the Latin 'vermis,' worm.
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