Eratosthenes was a Greek scholar, who lived in the 3rd century BC, renowned for his love of learning. Born in the Libyan city of Cyrene, which was once part of the Greek Empire, he received the equivalent of a university education when he was a teenager. He has been named as an all-round scholar, and during his life named himself as a poet, grammarian, philosopher, mathematician, astronomer, chronographer, and geographer in equal measure. He published works in several areas, and was also something of a problem solver.
His most famous works were in the fields of geography and mathematics, and he was known for creating the first map of the ancient world that featured latitude and longitude lines. He also used geometric formulas, and the sun, to calculate the Earth’s circumference to a 10% accuracy, and made measurements of the tilt of the Earth’s axis. These measurements led to further exploration by other scholars and geologists, and the production of maps and globes that were the most accurate in existence for hundreds of years.
Although there is very little evidence of Eratosthenes’ work around today, or details of his methodology and calculations, he has been referenced in publications by other noted scholars, such as Strabo. A three volume study on the Earth and the Earth’s measurement, Geographica by Eratosthenes, is still well-known in the geology field today.