The rain has started and the sky is turning the color of the lead in a number 2 pencil.

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The poem "O, I won't lead a homely life" was written in pencil below the score, though to an old folk tune.

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An analogy: think of a pencil, where the lead in the middle is the cellulose fiber, surrounded by unwanted lignin and hemicellulose.

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The tiny bones, each about the thickness of pencil lead, were first spotted three years ago by a local caretaker in the outwash from a steep hillside near a well-known fossil site outside Kunming, China.

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Belonging to a class of worlds known as diamond planets, 55 Cancri e is thought to be rich in the element carbon, which can exist in a variety of structural forms such as graphite (the material used as pencil lead), graphene, or diamond.

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