A class of fifth-graders from Green Acres Elementary in Lebanon, Ore., asked us to find out how pencil lead is made. That quest took us all the way back to the dawn of the universe and then all the way up to a factory in Jersey City, N.J.
In the process, we learned that pencil lead (actually not lead at all but a mineral called graphite) has a storied past.
Here’s the legend: In the mid-16th century, a storm uprooted a tree in England’s Lake District. Clinging to the tree’s roots was a shiny black substance — graphite! We don’t know how much truth there is to that story, but we do know that just a few decades later, the site had been transformed into the first commercial graphite mine.
At first, local shepherds were the only ones making use of graphite — it was perfect for marking their sheep.
The stuff looked and acted a lot like lead, so some called it plumbago (from the latin word for lead, plumbus) and sometimes “black lead.” That name stuck.
To make the graphite a bit easier to use, surveyors and artists wrapped sticks of plumbago in string or sheepskin. In 1565, Swiss naturalist Conrad Gessner published a drawing of a strip of graphite inside a tube of wood — the first depiction of a wood pencil. The invention swiftly spread through Europe.
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.