THINKER'S ALMANAC - March 30

Before the invention of the pencil eraser, what did people use to erase errors?

Subject:  Invention - Eraser-tipped Pencil

Event: Hyman L. Lipman patents pencil with eraser, 1858

 

The average pencil is seven inches long, with just a half-inch eraser - in case you thought optimism was dead. -Robert Breault

 

On this day in 1858, a Philadelphia stationer named Hyman L. Lipman patented the first eraser-tipped pencil.  This is one invention that has stood the test of time and is also one of the best metaphors there is to remind us that everyone makes mistakes and that no human is faultless.

One common misnomer about pencils is that they contain “lead.” In reality, pencils contain a mineral called graphite.  Legend has it that in the 16th century a shiny black substance was discovered in England’s Lake District under a fallen tree.  The substance was first used by local shepherds to mark their sheep. Because the black material resembled lead, it was called plumbago (from the Latin word for lead, plumbus — the same root that gave us the word “plumber,” someone who works with lead pipes).

 

A pencil shortage in 18th century France resulted in the invention of another well-known writing implement.  While at war with England in 1794, Revolutionary France could not access the graphite needed to make pencils.  An engineer named Nicolas-Jacques Conte improvised, combining low-quality graphite with wet clay. Conte then molded the substance into rods and baked it.  This process produced “Crayons Conte” or what we know today as chalk.

 

Before he lived at Walden Pond, the American writer Henry David Thoreau made a significant contribution to the pencil’s evolution.  After graduating from Harvard College, Thoreau went to work at his family’s pencil making business. Working with material from a New Hampshire graphite deposit, Thoreau developed his own process for making pencils.  He numbered his pencils from the softest to the hardest using a numbering system from 1 to 4. The No. 2 was the Goldilocks of pencils — not so soft that is smudged easily and not so hard that it breaks easily.

 

The origin of the most common color for pencils is another story.  Pencils were commonly painted in any number of colors, but in 1889, at the World’s Fair in Paris, a Czech manufacturer Hardtmuth debuted a yellow pencil.  Supposedly made of the finest graphite deposits, the pencil was named Koh-I-Noor, after one of the world’s largest diamonds. The distinct yellow of the Koh-I-Noor became the industry standard for quality, and soon other manufacturers began painting their pencils yellow.

 

The final key element in the evolution of the pencil came in the 1770s when British polymath Joseph Priestley discovered that a gum harvested from South American trees was effective for rubbing out pencil marks — appropriately he called this substance “rubber.”  Prior to Priestley’s discovery, the most common erasers used were lumps of old bread.

Priestley was also the author of an influential textbook called The Rudiments of English Grammar which was published in 1761 (1).

Recall, Retrieve, Recite, Ruminate, Reflect, Reason:  What individual contributions did the polymaths Henry David Thoreau and Joseph Priestly make to the pencil?

 

Challenge - Ordinary Objects, Extraordinary History: What are some examples of inventions, like the pencil, that are everyday ordinary objects?  Brainstorm a list of some ordinary objects that you encounter every day.  Select one of these objects and do some research on its origin. Write a report providing details about the object’s origin and history.  

Sources:

1-”Trace The Remarkable History Of The Humble Pencil.”  All Things Considered.  NPR.org 11 Oct. 2016.