Hyman Lipman patented the pencil with an eraser on top.
His patent included a metal ferrule to keep the eraser in place.
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Swimmer Michael Phelps smashed the world record for the 200-meter butterfly swim at just 15 years old.
The United States bought Alaska from the Russian Empire.
German mathematician Carl Friedrich Gauss constructed the first heptadecagon using a ruler and a compass.
Someone tried to shoot President Ronald Reagan.
Ether was used as an anesthetic for the first time, by American surgeon Crawford Long, in Athens, Georgia.