There was a terrible storm in near Borrowdale, England in 1564. As most bad storms do, it caused some damage to the surrounding area. An oak tree fell and a group of shepherds in the area found a large graphite deposit. At first they thought the deposit was coal. However, it did not burn like they expected. They then realized that the raw material made dark marks, much darker than the previous lead, and they began to use it to mark sheep. However, the graphite was soft and brittle, which caused some problems for the people trying to write with it. The story continues when someone decided to wrap string around the graphite to make it a little stronger. Eventually, another brain decided that the graphite should be placed in wooden sticks. The problem was, these wooden sticks had to be hollowed out by hand. Konrad Gesner of Switzerland, wrote the earliest description of this "pencil" in his Treatise on Fossils. It shows a picture of this author depicting "a wooden tube holding a piece of graphite." This "Gesner pencil" has a special history because some people believe it was used by Shakespeare.


GRAPHITE

   In 1795, Nicholas-Jacques Conte of France discovered the process of mixing graphite with clay. This mixture was then placed in a kiln fire, which produced a superior writing material. After the kiln fire, strips were cut and placed into wood. The pencils strength depended on the amount of graphite located in the mixture. The more graphite that was used, the softer the pencil that would result. This mixture of graphite and clay is still used in our "lead" pencils of today.

Ingredient Proportion of Pencil Lead                    
HB PENCIL LEAD  COLOUR PENCIL LEAD
 
1.PENCIL BOARD  
  Californian incense cedar wood is sawn into small slats, each the length of a pencil but half its thickness, and about nine pencils wide  
2.GROOVING  
  One by one,the slats pass under a router,it carves grooves that will become the channel down the middle ,that holds the lead .  
3.WITH TEH LEAD  
  The next machine fills the grooves with glue and that lays in the lead.  
 
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