The first of five clues. Each one below gives a little more away.
I contain no lead, and I never have.
A deposit found in England in the 1500s was so valuable that armed guards were posted over it.
Napoleon's blockade forced a French officer to invent my modern recipe by mixing the mineral with clay.
I can write about fifty kilometres before I am used up.
Wood, graphite, and an eraser on the end.
Pencil
The Borrowdale graphite was mistaken for a kind of lead when it was found, and the name has outlived the correction by five hundred years.
An enormous deposit of unusually pure graphite was found at Borrowdale in Cumbria in the sixteenth century, so valuable that the mines were flooded when not in use and guarded when they were. It was assumed to be a form of lead, and the name never recovered. When Napoleon's blockade cut France off from English graphite, Nicolas-Jacques Conté ground what little he had, mixed it with clay and fired it — and discovered that the ratio of clay to graphite controlled hardness. That accident of wartime scarcity is why pencils are still graded from soft to hard today.
Reading five clues at once is not the game. In the real thing they arrive one at a time and every wrong guess costs an hour. Play mystery #42 · today's mystery · the vault
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