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Benjamin Franklin Reference Libraries

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Lightning Rod
2010-10-21 17:15:50

A lightning rod is a metal conductor mounted on the top of a building and connected through a wire to the ground to protect the building from lightning. The rod should conduct the electricity from a lightning strike down through the wire instead of passing through the building. The rod is just a single component in the lightning protections system along with rooftop conductors and multiple...

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...

Word of the Day
attercop
  • A spider.
  • Figuratively, a peevish, testy, ill-natured person.
'Attercop' comes from the Old English 'atorcoppe,' where 'atter' means 'poison, venom' and‎ 'cop' means 'spider.' 'Coppa' is a derivative of 'cop,' top, summit, round head, or 'copp,' cup, vessel, which refers to 'the supposed venomous properties of spiders,' says the OED. 'Copp' is still found in the word 'cobweb.'
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