Drafting pencil1/9/2024 Graphite sticks were at first wrapped in string or in sheepskin for stability. Because graphite is soft, it requires some form of case. Graphite had to be smuggled out for use in pencils. When sufficient stocks of graphite had been accumulated, the mines were flooded to prevent theft until more was required. The value of graphite was soon realised 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. In German, the word for pencil is still Bleistift, literally lead pen. The black core of pencils is still referred to as lead, even though it never contained the element lead. Consequently, it was called plumbago (Latin for “lead ore”). Chemistry was in its infancy and the substance was thought to be a form of lead. This remains the only large scale deposit of graphite ever found in this solid form. This particular deposit of graphite was extremely pure and solid, and it could easily be sawn into sticks. The locals found that it was very useful for marking sheep. Some time before 1565 (some sources say as early as 1500), an enormous deposit of graphite was discovered on the approach to Grey Knotts from the hamlet of Seathwaite in Borrowdale parish, Cumbria, England. The word pencil comes from the Latin word pencillus which means “little tail”. They were used extensively by the ancient Egyptians and Romans. The archetypal pencil may have been the stylus, which was a thin metal stick, often made from lead and used for scratching in papyrus, a form of early paper. Old Soviet coloured pencils with box (circa 1959) Mechanical pencils have more elaborate casings that support mobile pieces of pigment core, which can be extended or retracted through the casing tip as needed. In order to use the pencil, the casing must be carved or peeled off to expose the working end of the core as a sharp point. Similar permanent casings may be constructed of other materials such as plastic or paper. The most common type of pencil casing is a thin wooden cylinder permanently bonded around the core. Grease pencils have a softer crayon-like waxy core that can leave marks on smooth surfaces such as glass or porcelain. Colored pencils are sometimes used by teachers or editors to correct submitted texts but are more usually regarded as art supplies, especially those with waxy core binders that tend to smear on paper instead of erasing. Charcoal pencils are mainly used by artists for drawing and sketching. Other types of pencil core are less widely used. Graphite pencils are used for both writing and drawing, and the result is durable: although writing can usually be removed with an eraser, it is resistant to moisture, most chemicals, ultraviolet radiation and natural ageing. Most pencil cores are made of graphite mixed with a clay binder, leaving grey or black marks that can be easily erased. They are noticeably distinct from pens, which dispense liquid or gel ink that stain the light color of the paper. Pencils create marks via physical abrasion, leaving behind a trail of solid core material that adheres to a sheet of paper or other surface. The case prevents the core from breaking, and also from marking the user’s hand during use. A pencil is a writing implement or art medium usually constructed of a narrow, solid pigment core inside a protective casing.
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