The Shocking Historical past of the Pencil – The Marginalian

Having beforehand explored such mysteries as who invented writing and the way sounds turned shapes, it’s time to show to one thing a lot much less mysterious, a seemingly mundane but enormously influential instrument of human communication: the common-or-garden pencil.

“Take a pencil to put in writing with on aeroplanes. Pens leak,” states the primary of Margaret Atwood’s 10 guidelines of writing. “But when the pencil breaks, you possibly can’t sharpen it on the airplane, as a result of you possibly can’t take knives with you. Subsequently: take two pencils.” However though the pencil has fueled such numerous feats of inventive tradition as celebrated artists’ sketchbooks, Marilyn Monroe’s soulful unpublished poems, Lisa Congdon’s gorgeous portraits, and David Byrne’s diagrams of the human situation, it has solely been round for slightly over 200 years. Within the altogether fascinating 100 Important Issues You Didn’t Know You Didn’t Know: Math Explains Your World (public library), John D. Barrow tells the story of this underrated technological marvel:

The trendy pencil was invented in 1795 by Nicholas-Jacques Conte, a scientist serving within the military of Napoleon Bonaparte. The magic materials that was so applicable for the aim was the type of pure carbon that we name graphite. It was first found in Europe, in Bavaria in the beginning of the fifteenth century; though the Aztecs had used it as a marker a number of hundred years earlier. Initially it was believed to be a type of lead and was known as ‘plumbago’ or black lead (therefore the ‘plumbers’ who mend our lead water-carrying pipes), a misnomer that also echoes in our discuss of pencil ‘leads’. It was known as graphite solely in 1789, utilizing the Greek phrase ‘graphein’ that means ‘to put in writing’. Pencil is an older phrase, derived from the Latin ‘pencillus’, that means ‘little tail’, to explain the small ink brushes used for writing within the Center Ages.

However the historical past of the pencil, like that of many seminal improvements, has a darkish aspect:

The purest deposits of lump graphite have been present in Borrowdale close to Keswick [England] within the Lake District in 1564 and spawned fairly a smuggling trade and related black financial system within the space. Through the nineteenth century a serious pencil manufacturing trade developed round Keswick in an effort to exploit the prime quality of the graphite.

And but the pencil trade blossomed:

The primary manufacturing facility opened in 1832, and the Cumberland Pencil Firm has simply celebrated its a hundred and seventy fifth anniversary; though the native mines have lengthy been closed and provides of the graphite used now come from Sri Lanka and different far-off locations. Cumberland pencils have been these of the best high quality as a result of the graphite used shed no mud and marked the paper very nicely.

Plain because it seems, nevertheless, the pencil has developed considerably since its invention:

Conte’s unique course of for manufacturing pencils concerned roasting a mix of water, clay and graphite in a kiln at 1,900 levels Fahrenheit earlier than encasing the ensuing mushy stable in a wood encompass. The form of that encompass will be sq., polygonal or spherical, relying on the pencil’s meant use — carpenters don’t need spherical pencils which might be going to roll off the workbench. The hardness or softness of the ultimate pencil ‘lead’ will be decided by adjusting the relative fractions of clay and graphite within the roasting combination. Industrial pencil producers sometimes market 20 grades of pencil, from the softest, 9B, to the toughest 9H, with the preferred intermediate worth, HB, mendacity halfway between H and B. ‘H’ means exhausting and ‘B’ means black. The upper the B quantity, the extra graphite will get left on the paper. There may be additionally an ‘F’, or Wonderful level, which is a tough pencil for writing slightly than drawing.

Barrow gives the science behind an oft-cited trivia factlet:

The unusual factor about graphite is that it’s a type of pure carbon that is without doubt one of the softest solids identified, and top-of-the-line lubricants as a result of the six carbon atoms that hyperlink to kind a hoop can slide simply over adjoining rings. But, if the atomic construction is modified, there may be one other crystalline type of pure carbon, diamond, that is without doubt one of the hardest solids identified.

For the mathematically-minded, Barrow gives a pleasant curiosity-quencher:

An attention-grabbing query is to ask how lengthy a straight line could possibly be drawn with a typical HB pencil earlier than the lead was exhausted. The thickness of graphite left on a sheet of paper by a mushy 2B pencil is about 20 nanometers and a carbon atom has a diameter of 0.14 nanometers, so the pencil line is simply about 143 atoms thick. The pencil lead is about 1 mm in radius and subsequently ? sq. mm in space. If the size of the pencil is 15 cm, then the amount of graphite to be unfold out on a straight line is 150? cubic mm. If we draw a line of thickness 20 nanometers and width 2 mm, then there shall be sufficient result in proceed for a distance L = 150? / 4 X 10^-7 mm = 1,178 kilometers.

100 Important Issues You Didn’t Know You Didn’t Know: Math Explains Your World goes on to discover such fascinating questions because the origami of the universe, what rugby has to do with relativity, how lengthy issues are more likely to survive, and extra.