Episode 237: Pencil Primer, Part 1

We kick off the Pencil Primer — a new series for anyone who wants to start at the beginning of pencildom. This installment traces graphite from the legendary Borrowdale lightning strike of 1564 to Nicolas-Jacques Conté's clay-and-graphite breakthrough during the Napoleonic Wars, plus the Thoreau family's role in standardizing the American pencil grade scale and a tour through HB-to-9B. Plus, Tim's…