Bifocals Ben invented bifocals in 1784. Ben needed eye glasses to

Bifocals
Ben invented bifocals in 1784. Ben needed
eye glasses to help him see things far away
and up close. A pair of eye glasses only corrected one or
the other of these problems so Ben had to carry two pairs
of glasses. Ben got tired of always having to switch
glasses, and he decided to put two lenses (one to see far
away and one to see up close) into one pair of glasses.
The top lens allowed him to see far away, and the bottom
lens allowed him to see up close. This new type of eye
glasses is called bifocals. "Bi" means two, and "focal"
means focus.
Franklin Stove
Ben invented the Franklin Stove between
1742 and 1744. The Franklin Stove is a
heater, not a cooking stove. Before the Franklin Stove,
people used fireplaces for heat. Fireplaces gave off some
heat, but most of the heat went up and out the chimney.
The Franklin Stove, however, gave off more heat than the
fireplace and used less fuel. Ben called his invention the
Pennsylvania Fire Place. Today, it is known as the
Franklin Stove.
Electricity
Ben suspected that lightning was an electrical
current in nature, and he wanted to see if he was
right. One way to test his idea would be to see if
the lightning would pass through metal. He decided to use
a metal key and looked around for a way to get the key up
near the lightning. He used a child’s toy, a kite, to prove
that lightning is really a stream of electrified air, known
today as plasma. His famous stormy kite flight in June of
1752 led him to develop many of the terms that we still
use today when we talk about electricity: battery,
conductor, condenser, charge, discharge, uncharged,
negative, minus, plus, electric shock and electrician.
Lightning Rod
Before Franklin's invention, lightning destroyed
or damaged many buildings. Franklin's understanding of
electricity allowed him to design the lightning rod, which
was a metal rod attached to the high point of a building. A
metal wire or cable ran from the rod, down the side of the
building, and into the ground. When lighting struck, the
electricity ran down the rod and cable and into the
ground, preventing damage to the building. Franklin came
up with the idea for the lightning rod in 1750, however it
was 1753 before he perfected the invention. Franklin
believed that the lightning rod was his most important
invention
Meteorology
In 1743, Ben observed that northeast storms
begin in the southwest. He thought it was odd that storms
travel in an opposite direction to their winds. He predicted
that a storm’s course could be plotted. Benjamin rode a
horse through a storm and chased a whirlwind threequarters of a mile in order to learn more about storms. So,
in a way, Ben was a weatherman too! He even printed
weather
forecasts
in
his
almanack.
Today’s
meteorologists don’t chase storms on horseback, but they
do continue to plot the course of storms.
Odometer
As postmaster, Benjamin had to figure out routes for
delivering the mail. He went out riding in his carriage to
measure the routes and needed a way to keep track of
the distance. He invented a simple odometer and
attached it to his carriage.
Extension arm
Having helped found a library in Philadelphia, Franklin
spent a lot of time in the stacks. To help him reach books
on upper shelves that were out of his reach, he created
an extension arm. The device had two "fingers" that were
attached to the end of a long piece of wood or pipe. The
fingers could be opened or closed by pulling on a cord
that manipulated them. Similar devices are still used
today.
Street Lights
The street lamps in Ben's day were not very
efficient and the glass globes tended to become
dark with soot from the oil burned inside, requiring
almost daily cleaning. Franklin determined that the
problem had to do with a lack of airflow within the globe.
Ben suggested making them of four flat panes, with a
long funnel above to draw up the smoke, and an opening
letting air in below, to help the smoke leave the lamp. This
helped keep the street lamps clean until morning.
Daylight Savings Time
In 1784, while Ben was living in France, he
wrote a funny letter to the Journal of Paris, in
which he suggested that it would be more thrifty to use
natural light than to burn candles or oil lamps. In his letter
Ben suggested that the city of Paris pass a number of
laws which would force Parisians to get up with the sun
and retire early in the evening. We will never know if
Franklin intended anyone to take his idea seriously, but
every March and November people reset their clocks to
"spring ahead" or "fall back."
Swim Fins
Ben loved the water. Growing up in
Boston, he was drawn to the sea and
often dreamed of becoming a sailor. Ben
learned to swim and became an expert swimmer.
Wanting to increase his speed in the water, Franklin
devised fins that he wore on his hands. The fins were
shaped like lily pads or an artist's paint pallet and helped
the swimmer attain greater speed with each stroke. Today
fins are used by swimmers on their feet to help them
swim faster.
Glass Armonica
Ben found simple beauty in simple tunes. He
played several musical instruments, including the violin,
harp and guitar. His great interest in music led him to
build his own glass armonica. This simple musical
instrument was played by touching the edge of the
spinning glass with dampened fingers. The armonica’s
beautiful tones appealed to many composers, including
Mozart and Beethoven.
Fire Department
On a visit to Boston, Ben noticed that the people
of that city were far better prepared to fight fires
than the people of Philadelphia. When he returned home he
worked to raise people’s awareness about the need to
improve methods of fire-fighting. Until then people relied on
the goodwill of neighbors to help put out a fire. Ben did not
think that was enough and he created a club made up of men
belonging to a fire engine whose job was to attend all fires that
broke out. This led to a group of thirty men coming together to
form the Union Fire Company on December 7, 1736. Their
equipment included leather buckets, with strong bags and
baskets (for packing and transporting goods), which were to
be brought to every fire. Thanks to Ben, Philadelphia became
one of safest cities in the world in terms of fire damage.
Library
When Ben was 21 he created the Junto, a
group of men like himself who wanted to
improve their community. They got together to discuss
important issues. One of their favorite things to do was
read, but books were hard to find and expensive. Ben
came up with the idea of a subscription library, which
would put together the money of the members to buy
books for all to read. This was the beginning of the Library
Company of Philadelphia begun by Ben in 1731. While
the books were originally kept in the homes of the first
librarians, they eventually began to be stored in public
buildings. Libraries soon began to appear in other cities
and that led to the public libraries of today.