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The Pencil



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This ubiquitous instrument is cheap and always at hand.  It is often given away as promotional items, with companies names printed on its side. What are it’s origins and how do you manage to get the pencil into the centre of the wood?  A question that a lot of young minds ask, and for that matter a lot of adults as well.

 Essential Characteristics

Well, the pencil is a instrument of marking. It is scrapped across the surface and a small bit of itself is left behind.  Some even say that it is anther from of a medium for art. It is used by a wide range of artists, writers and trade personal. Although the writing can usually be removed with an eraser, it is resistant to moisture, most chemicals, ultraviolet radiation and natural ageing. It can also conduct electricity.

Essentially, it is composed of graphite, which is compressed vegetation. When used commercially it is mixed with clay in various  proportions to give different characteristics, such as hardness and tone.

This mark that is left behind on the paper can then be erased with a rubber compound, and for a lack of  a more imaginative name, called an “Eraser”. Besides the manual eraser there exists the electrical eraser which is very useful with certain drawing techniques.  There is enough information on the eraser to write an article on that alone.

The graphite is then covered with a wooden sheath to give it protection from breaking and to allow the graphite to be held in the hand easily. This wooden covering can be in the shape of hexagon, octagon or round, and in some cases flat. Not all pencils are held in a wooden sheath, there are some flexible resins that allows the pencil to be bent. Naturally that also means that the graphite inside is flexible as well, and that it will not break when bent. Paper has also been used to house the graphite as well.  These casing have to be cut away to shape the graphite into a finer pint for detailed fine detailed work.  

The hardness of the lead is indicated by a number that is stamped on the side. The higher the number, the harder the lead. There are other markings used: H indicates hard, B indicates the blackness of the pencil's mark, and F indicates that the pencil can sharpen to a fine point. Combinations are used: HB, hard and black; HH, very hard.

There are mechanical pencils that allow the graphite to be replaced, merely by pushing down on the head and sliding the new piece of graphite into the hard casing.  This casing may be metal or hardened plastic.

Some time pencils are referred to a lead, but there is no lead in the graphite at all.

 History

This concept of pencils containing lead probably can be traced back to Roman times. In those days a metal rod was used to scribe onto papyrus or parchment, hence the name lead. Also termed  Plumbago (Latin for "lead ore"). The black core of pencils is still referred to as lead.  In German, the word for pencil is still Bleistift, literally lead stick.  Graphite pencils are not toxic either ingested or placed physically into the skin.

It was not until the Swedish chemist Carl W. Scheele (1779)  determined that black lead was actually a form of carbon. In 1789, German geologist Abraham G. Werner reportedly gave it the name graphite, after the Greek graphein, meaning "to write."

The name pencil has its origins in the Latin name pencillus which means "little tail".

This name is a little misleading to say the least, as  brushes and inks were used.

But pencils as we know them can give thanks to the extremely rich graphite despite found in  Borrowdale parish, Cumbria, England,  some time before 1565 ( The graphite was originally called marking stones). Other sites have been found, but none can compare in terms of richness and quality. Graphite from these other sites have to be ground down and  the impurities removed, then clay mixed into it to give  it’s form. Other additives were tried, such as sulphur, gum and various glues. In 1795, French chemist and Napoléon courtier Nicolas-Jacques Conté invented a process to mix graphite with clay and water, a process that is still used today. (There is a name brand called Conté)

The value of graphite was soon realized to be enormous, mainly because it could be used to line the moulds for cannonballs, and the mines were taken over by the Crown and guarded. When sufficient stocks of graphite had been accumulated, the mines were flooded to prevent theft until more was required. During that time period, graphite had to be smuggled out for use in pencils.

Because graphite is soft, it requires some form of  casing or protection. Initially graphite sticks were  wrapped in string or in sheepskin for stability.  As the pencil wore down,  the string was then unrolled to reveal more of the graphite.

Once the usefulness of these early pencils were demonstrated, the news spread far and wide, attracting the attention of artists all over the known world.  England continued to dominate the production of pencils until a method of reconstituting the graphite powder was found. The characteristically  square English pencils continued to be made with sticks cut from natural duck graphite into the 1860’s. The town of  Keswick,  near the original findings of block graphite still manufactures pencils, the factory also being the location of the Cumberland pencil museum.

Modern day manufacturing process.

Today the process remains pretty much the same.  The graphite is crushed and mixed with water.  The resulting sludge is the air dried.  Then this is mixed again with water to form a past that is extruded very much like spaghetti.  This paste may be darkened by adding a darker carbon. This is then cut into shortened lengths and  then oven dried in temperatures of about 1000 º C.   

To place the graphite into the wood casing is a very simple process.  Blocks of wood have little parallel grooves cut into them, and the graphite placed into these. A corresponding mirror image of a block is then placed on top of the first and glued into position.  This sandwich is then sliced into the smaller strips. The results are then sanded and painted to give a acceptable finish. Originally the pencils very left unfinished and unstamped to show the gains of the wood, the aesthetical value was prized. It was only in the 1890´s did the manufactures start stamping the names on the wood casings.

Initially red cedar was used, but this proved to be in short supply, so incense cedar is now used, a species that grows in California's Sierra Nevada Mountains. The red cedar was popular in the earlier days as it had a very pleasant smell,  but the modern cedar that is used today has been artificially  scented.

In some cases, a recess is cut,  to which a ferrule is added, so that the  eraser can be added. In about the 1850’s a  French merchant-adventurer named Jean-Pierre Alibert discovered a very pure graphite along the Russian-Chinese border.  He then started mining and began shipping the graphite around the world. These pencils that were made of high-quality Asian graphite, were painted yellow to indicate the source of the graphite.

Additional points of interest

Laid end-to-end, the number of pencils made annually in the U.S. would encircle Earth about 15 times.

In 1858, erasers were attached to the ends of pencils for the first time; most pencils in the U.S. have erasers, but those in Europe do not. A pencil lead or a line drawn by a pencil will conduct electricity.

Coloured pencils are made from chalk, clay, or wax mixed with binders and pigments About 75% of the 2.8 billion pencils manufactured annually in the U.S. are still painted yellow.

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