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Hero of Alexandria

math Maturity 11-13 Next article →

Hero of Alexandria was a brilliant thinker from a very long time ago. He lived in the city of Alexandria in Egypt during the Roman era. People called him a great experimentalist because he loved to test his ideas. He was both a mathematician and an engineer. This means he studied numbers and also built clever machines. His work helped people understand how the world works.

Aeolipile illustration
Aeolipile illustration

Hero created many amazing inventions that used natural forces. He described a steam-powered device called an aeolipile. This was a very early kind of steam engine. He also built a windwheel to catch the wind on land. This wheel could even power a musical organ. He even made a vending machine for water. You could drop a coin into a slot to get a drink.

Hero - De automatis, 1589 - 116959
Hero - De automatis, 1589 - 116959

We do not know everything about Hero's early life. He lived around the year 10 AD to 70 AD. Some scholars think he saw a lunar eclipse in 62 AD. He used ideas about the earth from a man named Eratosthenes. Eratosthenes said the earth's circumference was 252,000 stades. Alexandria was a busy city where many different people lived together. Hero may have taught students at a famous place called the Mouseion.

Math was a huge part of Hero's work. He wrote a book called Metrica about shapes and sizes. Most people remember him for Heron's formula. This is a way to find the area of a triangle. You only need to know the lengths of its three sides. He also found ways to calculate square roots and cube roots. He even studied how light travels in the shortest possible path.

Aeolipile illustration
Aeolipile illustration

Many of Hero's original papers were lost over time. We know about him because of old books from the Byzantine Empire. Some of his ideas were saved in Arabic or Latin translations. His work on machines was like the very first research into cybernetics. This is the study of how machines and humans work together. Even though he lived so long ago, we still use his math today.

Hero - De automatis, 1589 - 116959
Hero - De automatis, 1589 - 116959
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File:Aeolipile illustration.png
Aeolipile illustration.png
File:Hero - De automatis, 1589 - 116959.jpg
Hero - De automatis, 1589 - 116959.jpg
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