360The 1790s: the first vaccine and the metric system
In 1796, Edward Jenner tested the first vaccine, against smallpox, a breakthrough that would save hundreds of millions of lives. France introduced the metric system, now used almost everywhere. Eli Whitney's cotton gin transformed farming, and French soldiers in Egypt found the Rosetta Stone, the key to reading hieroglyphs.
Smallpox was one of history's deadliest diseases. The English doctor Edward Jenner noticed that milkmaids who caught mild cowpox seemed protected from it. In May 1796, he tested this by giving cowpox to a boy, James Phipps, who then proved immune to smallpox. The word vaccine comes from the Latin for cow. Vaccination eventually led to smallpox being eradicated in 1980.
France wanted one clear system of measurement. Scientists defined the metre as a fraction of the distance from the North Pole to the equator, and in 1795 France adopted the metric system. Its simple decimal units are now used by nearly every country.
In 1793, the American inventor Eli Whitney patented the cotton gin, a machine that quickly separated cotton fibres from seeds.
In July 1799, French soldiers near the town of Rashid, known in English as Rosetta, found a stone carved with the same decree in three scripts, including Greek and Egyptian hieroglyphs. Scholars later used it to decipher hieroglyphs, unlocking the history of ancient Egypt.
At the end of the decade, Alessandro Volta was completing his electric pile, the first battery, announced in 1800.
- 1793
- Whitney's cotton gin
- 1795
- France adopts the metric system
- 1796
- Jenner's smallpox vaccine
- 1799
- Rosetta Stone found
Sources: Britannica · World Health Organization · British Museum.