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rocks and minerals app
Rocks and Minerals
structure of earth app
Structure of earth
simple machines app
Simple Machines
magnets app
Magnets
adaptations in animals app
Animal Adaptations
adaptations in plants app
Plant Adaptations
diseases app
Diseases
solar system app
Solar System

Welcome to FunAppSchool

FunAppSchool

IPad and IPhone Apps

Educational Games for IPad and IPhone. English Grammar and Science Apps for Elementary and Middle School Kids.

Pencils

One of the oldest and most widely used tools in the world is the pencil. It has been used for centuries to draw on various surfaces.

The Greeks and Roams were the first to use pieces of lead to draw lines on papyrus, but it was around the 1400s that pencils were made.

The first of the pencils were called lead pencils and were made of strips of a mineral called graphite (similar to lead) wrapped heavily in twine to make it easy to hold.

In Germany, around 1779 a method of gluing pieces of wood around the graphite was discovered and the modern pencil was born.

Graphite is mined like many other natural forms of rock, and the main graphite mine eventually wore off. A substitute material was needed to supply pencil manufacturers.

Then a French chemist named Nicolas Jacques Conte discovered that when powdered graphite, powdered clay and water were mixed, and then baked, the finished product wrote no differently to the earlier pure graphite.

He also figured out that by increasing or lessening the amount of clay and graphite determined the hardness or softness of the pencil.

The first pencils in America were manufactured in 1812, and a cabinetmaker called William Monroe invented a machine that could make pencils.

Today there are many types of pencils, and a letter and number identifies the hardness or softness of the pencil. One is usually considered soft, and higher numbers mean harder pencils.

Hyman W. Lipman another American who came up with the idea of attaching an eraser on top of the pencil.

There are other types of pencils in the market today, that are not like the traditional pencil, yet do the same job.

They are called automatic, propelling or repeating pencils. They have thin strips of lead (like those found in wooden pencils) inserted into a plastic or metal case (which replaced the wood).

There is a mechanical system with a spiral and rod inside the case, which pushes the lead forward when a button is pressed.

By the early 20th century, coloured pencils, which had graphite cores, yet dye or pigments of different colours were introduced. Today there are over 70 colours.

The process of inventing traditional pencils starts with a block of wood, which is cut into slats and then stained and shaped to the shape of the pencil.

Little grooves are cut through the slats and strips of lead are inserted through them. Then a second slat is placed on top of the first and they are glued together.

Then this “pencil sandwich” is passed through a cutting process to separate each individual pencil.

The products are then painted, smoothened, the eraser is fixed on top, and the product is ready to be shipped off.

Pencils are amazing things. Each pencil is able to write over 40,000 words, or draw a line about 70 kilometres long!

We learn to write with pencils even before we do with pens, and therefore, these instruments remain an important part of our lives.