pencil

             It was as early as 1564 that a "pencil" similar to what we know today was in use. That
             year, during the reign of Queen Elizabeth, a deposit of graphite (black carbon) was found in
             Borrowdale, Cumbria. It was so solid and uniform that it could be sawn into sheets and cut
             into thin square sticks. Not much chemistry was known in 1564, so the material was called
             plumbago, or something which is like lead. The graphite of the Borrowdale mines was the
             only deposit ever found, and had a huge value. It was only mined six weeks per year. It had
             to be escorted by armed guards in wagons to London and was illegal to export of the ore.
             The wooden cases were handmade by the English Guild of Pencilmakers, who in turn held a
             No other pure deposits of graphite were found in any other part of the world. The
             few impure mines which were found in the other parts of the world had to be crushed and
             have the impurities removed. Many experiments were made to find a binder to reform the
             ground ore into usable sticks. The problem was prabably first solved by the germans
             because by the seventeenth century, they used a mixture of graphite, sulphur and antimony.
             The processes were trade secrets and the German lead sticks soon competed for favour with
             It was not until 1779, when a chemist named K.W. Scheele, made a analysis of
             plumbago and proved it to be a form of carbon, not of lead; still it was not until 1789, when
             A.G. Werner suggested to rename the substance to the more appropriate name of graphite,
             It wasn't until 1795 that the Geramns process was finally discovered. War had cut
             off France from the English and German sources of pencil supply, and Nicholas Jacques
             ContJ, an officer in Napoleon's army, was commissioned to develop a satisfactory
             substitute. The young inventor mixed powdered graphite with clay and fired the mixture
             ...

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