German mathematician Carl Friedrich Gauss constructed the first heptadecagon using a ruler and a compass.
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Ether was used as an anesthetic for the first time, by American surgeon Crawford Long, in Athens, Georgia.
The US adopted the 15th Amendment, guaranteeing citizens the right to vote.
North Carolina repealed its controversial bathroom law that restricted transgender use.
Vincent van Gogh's famous painting 'Sunflowers' was sold for an incredible $39.7 million, the most ever paid for a painting.
An orbital-class rocket was successfully reused for the first time.
