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|Title||An Interpretive Note on Pencils|
|Type||Papers and Articles: OSV Research Paper|
While Borrowdale pencils were the best available in the 17th, 18th, and early 19th centuries, they were in limited supply and far from the only pencils to be had! Graphite, although of inferior grades and quarried in pieces too small to be sawn into pencil slips, was also mined in Scotland, France, Spain, Germany, and America. (This graphite was used in the casting of iron and brass, and as a machine lubricant, in addition to being made into pencils.) In 1760, for example, Kaspar Faber established a pencil manufactory in Stein, near Nuremburg, Germany. Faber initially used pulverized graphite cemented together with a mixture of resins, glues, gums, and sulphur. By the late 1700s many European pencil makers, who like Faber did not have access to Borrowdale graphite, were grinding inferior pieces of Continental graphite and mixing it with melted sulphur or glue. It was poured into molds, and when cooled looked "nearly like the coarser sorts of black lead itself." Unfortunately, "pencils of this kind are hard and brittle, and cut or scratch the paper... instead of marking" it. Therefore, many makers added a little tallow for softness, which in turn made the mark of such a pencil slightly greasy. This kind of pencil was still being made for such secondary uses as carpenters' pencils into the early 20th century. There was an easy test to see if your pencil was solid graphite or an inferior one made of powdered graphite and sulphur. Pure graphite will not melt or burn in a candle flame, or when pressed on a red hot iron, but a mixture of graphite and sulphur will. If there is enough sulphur, the latter might even burn, with a blue flame and sulphur's unmistakable brimstone smell.
Up to the end of the 18th century, pencilmaking either relied on a single English mine for slabs of high quality solid graphite, or used the German method. A better way was discovered by the French chemist and engineer Nicholas Jacques Conte' in 1795. At this time the wars of the French Revolution, which spilled into the Napoleonic Wars, were taking place. England and France were doing more fighting than trading for about 25 years and the French could not get good Borrowdale lead pencils. Conte's innovative method was to mix clean, pulverized graphite with washed clay, and grind the two materials together with water until they formed a stiff dough. The dough could then be extruded (i.e. squeezed through small holes) into thin, round strands and cut to the desired length. These spaghetti-like strands were air-dried before being fired at 2000 degrees Fahrenheit in a closed crucible for several hours, in effect, making a ceramic pencil lead. Hardness and blackness could be varied by altering the temperature of the kiln and the proportions of graphite and clay, (instead of adding messy tallow!). Conte's method is still the way pencils are made today. It seems, however, that his innovations were not widely adopted in the United States until the mid-19th century. Up until that time, Americans used approximately the same bonding of powdered graphite with sulphur and glue that the Germans did.