Eratosthenes
Topic: Geography as a Discipline: Nature, Branches and Approaches · NCERT: Class 11, Ch 1 "Geography as a Discipline"
Meaning
Eratosthenes (276–194 BC) was a Greek scholar. He was the first person to use the word "geography", which means "description of the earth". He was librarian at Alexandria in Egypt. He is also famous for measuring the size of the earth with simple observation and geometry, long before modern tools existed.
Example
At noon, the sun's angle at Syene (modern Aswan, in southern Egypt) was different from its angle at Alexandria, on Egypt's north coast. The gap was about 7.2°, or one-fiftieth of a full circle. Eratosthenes multiplied the distance between the two cities by fifty, and his figure for the earth's circumference came very close to the true one.
Don't confuse with
- Ptolemy: Ptolemy wrote Geographia in the 2nd century AD and drew a world map using coordinates. Eratosthenes coined the word "geography" much earlier. Herodotus and Aristotle did not coin the term.