Lead pencil, 1564
Any schoolboy worth his salt knows pencils do not in fact contain potentially poisonous lead. And they never did; the pencil arrived with the discovery in 1564 in Borrowdale, Cumbria, of a pure deposit of graphite, then thought to be a type of lead. A year later, the German naturalist Conrad Gesner described a wooden writing tool that contained the substance. Nicolas Conté perfected the pencil more than a century later by mixing graphite with clay and gluing it between two strips of wood.
Any schoolboy worth his salt knows pencils do not in fact contain potentially poisonous lead. And they never did; the pencil arrived with the discovery in 1564 in Borrowdale, Cumbria, of a pure deposit of graphite, then thought to be a type of lead. A year later, the German naturalist Conrad Gesner described a wooden writing tool that contained the substance. Nicolas Conté perfected the pencil more than a century later by mixing graphite with clay and gluing it between two strips of wood.
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