Bifocals are eyeglasses with two distinct optical powers. Bifocals are commonly
prescribed to ... Benjamin Franklin is generally credited with the invention of
bifocals. ... of The Gazette of the Un...
In 1990 the year of the bicentennial celebration of Benjamin Franklin's death ..... “
It seems most likely that Benjamin Franklin did invent bifocals, most likely when ...
Benjamin Franklin's inventions, innovations and discoveries including the kite
experiment, Franklin stove, bifocals, armonica and more.
Benjamin Franklin invented the lightning rod - iron furnace stove - bifocal ...
Franklin's armonica, created in 1761, was smaller than the originals and did not ...
Bifocals. Benjamin Franklin was always faced with a problem of vision. ...
Contrary to popular opinion, Benjamin Franklin did not invent or discover
Nov 6, 2013 ... On bifocals, Benjamin Franklin assured his vision-impaired friends that they
would enjoy and possibly extend the later years of their life with ...
When Franklin was a postmaster he had to organize routes for efficient mail
delivery. He needed to know distances and traveling times, so he invented a
Some of his inventions, like bifocal glasses, are well-known, while others are
more ... Of the numerous inventions Franklin created, he did not patent a single
one. ... Three-wheel clock: Franklin invented a 24-hour, three-wheel clock that
Jul 22, 2005 ... Glass lenses, for use as magnifiers or for starting fires, date to about 300 BC, ... to
aid or correct vision were almost certainly invented in 1280 in Florence, ... Bifocal
spectacles were described in Franklin's in a further letter to ...
Jul 7, 2016 ... Did Benjamin Franklin Invent the Bifocal? ... in 1785; a letter written by a friend in
1789 claims that he had used them for the past 50 years.