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Conrad Gessner

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Morgan Highsmith

on 4 June 2014

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Transcript of Conrad Gessner

Conrad Gessner
In Egypt the scribes used to use thin metal to leave a light mark on papyrus.
Who Made the First Pencil?
One of the first pencils
Early American pencils were made with Eastern Red Cedar, a strong splinter- resistant wood.
What Did the First Pencil Look Like?
One of the earliest mechanical pencils
The Eversharp mechanical pencil was made by Charles Rood Keeran.
The Eversharp Mechanical Pencil
How the First Built in Pencil Eraser Worked
In 1858 a man named Hymen Lipman made a new pencil with a rubber plug embedded in one end of its wood shaft.
Who Made the First Pencil Eraser?
The History of Pencils
By Madeleine Bolivar, Abdallah Khourma, and Lucia Maldonado
A Modern Pencil
Modern pencils range from very hard to very soft-H9 (hardest) to 9B(softest).
Modern Pencils
Charles Rood Keeran
Charles Rood Keeran
Charles R. Keeran was the inventor of one of the first pencils, the Eversharp. But before he made the Eversharp he made a two-piece vacuum seal for Mason Jars, this was immediately popular. However he sold off his company in order to finance his favorite invention, the Eversharp mechanical pencil.
A pencil after it is sharpened.
Most pencil cores are made of graphite with a clay binder, leaving a greyish mark that is easy to erase.
More on Modern Pencils
Then Conrad made the first pencil with lead stick.
And in England, A large deposit of graphite was discovered near Greg Knotts during the first half of the 1500's and figured out that it leaves a darker mark than lead.
They made many tree industries in the South, there are still some of the industries in Tennessee.
When they first started making pencils they put a piece of lead in between two slabs of wood.
You had to sharpen the end to get more eraser out.
The HB pencil indicates a medium hardness.
It was not until the 18th century that early pencils were produced.
In the 18th century, local residents cut the graphite into sticks and used them to mark their sheep.
The Eversharp mechanical pencil
Although it is easy to erase with an eraser it is resistant to moisture, most chemicals, ultra violet radiation and natural aging.
The first Eversharps were manufactured in December of 1913.
Then in 1915 Keeran teamed up with the wahl Adding Machine Company.
Afterward in 1917 Keeran got kicked out of the company.
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