Origin of rubber
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Author:zywenju
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Published time: 2019-03-20
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People use erasers, up to now only two hundred years of history.Erasers, which can erase pencil words, were first discovered by English scientist Priestley in 1770. Before that, people used bread to erase pencil words.
People use erasers, up to now only two hundred years of history.
Erasers, which can erase pencil words, were first discovered by English scientist Priestley in 1770. Before that, people used bread to erase pencil words.
It's made of natural rubber. You don't get crumbs when you erase. You just stick the end of the pencil on the rubber and it gets dirtier and dirtier. Later, materials such as sulfur and oil were added to make erasers, which made them easy to drop.
