Back in the days when writers used pencil and paper to express themselves, there were inevitably mistakes that needed attention. Before erasers were invented in 1770, a little bread and water did the trick -- writers simply took a small piece of bread (without the crust), moistened it, balled it up, and rubbed away the typos.
In the late 18th century, Joseph Priestley discovered a substance -- later known as rubber because it was used to rub away errors -- that would remove marks made by a black lead pencil. The substance, first known as India gum, actually releases the graphite particles clinging to the paper's fibers. British engineer Edward Nairne expanded on the idea and marketed the first rubber erasers in Europe.
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