How Did People Fix Written Mistakes before Rubber Erasers?

Before the invention of rubber erasers, people used bits of moistened bread
to erase written mistakes.

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.
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