The Inventions and Scientific Achievements of Benjamin Franklin

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Benjamin Franklin's glass armonica
A modern day version of Benjamin Franklin's glass armonica. Tonamel/Flickr/CC BY 2.0

"Of all my inventions, the glass armonica has given me the greatest personal satisfaction."

Benjamin Franklin was inspired to create his own version of the armonica after listening to a concert of Handel's Water Music which was played on tuned wine glasses.

Benjamin Franklin's armonica, created in 1761, was smaller than the originals and did not require water tuning. Benjamin Franklin's design used glasses that were blown in the proper size and thickness which created the proper pitch without having to be filled with water. The glasses were nested in each other which made the instrument more compact and playable. The glasses were mounted on a spindle which was turned by a foot treadle.

His armonica won popularity in England and on the Continent. Beethoven and Mozart composed music for it. Benjamin Franklin, an avid musician, kept the armonica in the blue room on the third floor of his house. He enjoyed playing armonica/harpsichord duets with his daughter Sally and bringing the armonica to get together at his friends' homes.

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Franklin Stove

Benjamin Franklin - Franklin Stove
Benjamin Franklin - Franklin Stove.

Fireplaces were the main source of heat for homes in the 18th century. Most fireplaces of the day were very inefficient. They produced a lot of smoke and most of the heat that was generated went right out the chimney. Sparks in the home were of great concern because they could cause a fire that would quickly destroy the homes, which were constructed mainly with wood.

Benjamin Franklin developed a new style of the stove with a hoodlike enclosure in the front and an airbox in the rear. The new stove and reconfiguration of the flues allowed for a more efficient fire, one that used one-quarter as much wood and generated twice as much heat. When offered a patent for the fireplace's design, Benjamin Franklin turned it down. He did not want to make a profit. He wanted all people to benefit from his invention.

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Lightning Rod

Benjamin Franklin Experiments With Kite
Benjamin Franklin Experiments With Kite.

In 1752, Benjamin Franklin conducted his famous kite flying experiments and proved that lightning is electricity. During the 1700s lightning was a major cause of fires. Many buildings caught on fire when struck by lightning and kept burning because they were built mainly of wood.

Benjamin Franklin wanted his experiment to be practical, so he developed the lightning rod. A tall rod is attached to the outside wall of the house. One end of the rod points up into the sky; the other end is connected to a cable, which stretches down the side of the house to the ground. The end of the cable is then buried at least ten feet underground. The rod attracts the lightning and sends the charge into the ground, which helps to decrease a number of fires.

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Benjamin Franklin - Bifocals
Benjamin Franklin - Bifocals.

In 1784, Ben Franklin developed bifocal glasses. He was getting old and was having trouble seeing both up-close and at a distance. Getting tired of switching between two types of glasses, he devised a way to have both types of lenses fit into the frame. The distance lens was placed at the top and the up-close lens was placed at the bottom.

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Map of Gulf Stream

Benjamin Franklin - Map of Gulf Stream
Benjamin Franklin - Map of Gulf Stream.

Ben Franklin always wondered why sailing from America to Europe took less time than going the other way. Finding the answer to this would help to speed travel, shipments and mail deliveries across the ocean. Franklin was the first scientist to study and map the Gulf Stream. He measured wind speeds and current depth, speed, and temperature. Ben Franklin described the Gulf Stream as a river of warm water and mapped it as flowing north from the West Indies, along with the East Coast of North America and east across the Atlantic Ocean to Europe.

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Daylight Savings Time

Benjamin Franklin - Daylight Savings Time
Benjamin Franklin - Daylight Savings Time.

Ben Franklin believed that people should use daylight productively. He was one of the greatest supporters of daylight savings time in summer.

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odometer. PD

While serving as Postmaster General in 1775, Franklin decided to analyze the best routes for delivering the mail. He invented a simple odometer to help measure the mileage of the routes that he attached to his carriage.