The modern pencil was invented in 1795 by Nicholas-Jacques Conte, a scientist serving in the army of Napoleon Bonaparte. The magic material that was so appropriate for the purpose was the form of pure carbon that we call graphite. It was first discovered in Europe, in Bavaria at the start of the fifteenth century; although the Aztecs had used it as a marker several hundred years earlier. Initially it was believed to be a form of lead and was called ‘plumbago’ or black lead (hence the ‘plumbers’ who mend our lead water-carrying pipes), a misnomer that still echoes in our talk of pencil ‘leads’. It was called graphite only in 1789, using the Greek word ‘graphein’ meaning ‘to write’. Pencil is an older word, derived from the Latin ‘pencillus’, meaning ‘little tail’, to describe the small ink brushes used for writing in the Middle Ages.
THE DARK SIDE
The purest deposits of lump graphite were found in Borrowdale near Keswick [England] in the Lake District in 1564 and spawned quite a smuggling industry and associated black economy in the area. During the nineteenth century a major pencil manufacturing industry developed around Keswick in order to exploit the high quality of the graphite.
The first factory opened in 1832, and the Cumberland Pencil Company has just celebrated its 175th anniversary; although the local mines have long been closed and supplies of the graphite used now come from Sri Lanka and other far away places. Cumberland pencils were those of the highest quality because the graphite used shed no dust and marked the paper very well
An Interesting Question
An interesting question is to ask how long a straight line could be drawn with a typical HB pencil before the lead was exhausted. The thickness of graphite left on a sheet of paper by a soft 2B pencil is about 20 nanometers and a carbon atom has a diameter of 0.14 nanometers, so the pencil line is only about 143 atoms thick. The pencil lead is about 1 mm in radius and therefore ? square mm in area. If the length of the pencil is 15 cm, then the volume of graphite to be spread out on a straight line is 150? cubic mm. If we draw a line of thickness 20 nanometers and width 2 mm, then there will be enough lead to continue for a distance L = 150? / 4 X 10-7 mm = 1,178 kilometers.
Imagine a life without Pencil