Eratosthenes

Definition

Eratosthenes was a Greek mathematician, astronomer, and geographer who lived in the 3rd century BCE. He is best known for calculating the Earth's circumference with remarkable accuracy and for being the chief librarian at the Library of Alexandria, a major center of knowledge during the Hellenistic period. His contributions greatly impacted the understanding of geography and mathematics in major Hellenistic cities like Alexandria, Antioch, and Pergamon.

5 Must Know Facts For Your Next Test

1. Eratosthenes is credited with being the first to calculate the Earth's circumference using simple geometry based on shadows cast by sticks at different locations.
2. He devised a system of latitude and longitude that laid the groundwork for modern cartography, influencing how geography was studied in Hellenistic cities.
3. As chief librarian at the Library of Alexandria, he collected and cataloged vast amounts of knowledge, making significant contributions to various fields including mathematics, astronomy, and literature.
4. Eratosthenes introduced the concept of 'geography' as a scientific discipline, marking a shift in how people understood the world around them.
5. He was one of the first to suggest that the Earth was round, challenging earlier beliefs about its shape and paving the way for future exploration and discovery.

Review Questions

• How did Eratosthenes use geometry to calculate the Earth's circumference, and what does this reveal about his mathematical skills?
  • Eratosthenes calculated the Earth's circumference by measuring the angle of shadows cast by sticks in different locations at noon during the summer solstice. By knowing the distance between these two locations and applying basic geometry, he was able to extrapolate the Earth's total circumference. This method demonstrated not only his mathematical skills but also his innovative approach to using simple observations to make significant scientific discoveries.
• Discuss the role of the Library of Alexandria in promoting Eratosthenes' work and contributions to knowledge during the Hellenistic period.
  • The Library of Alexandria played a crucial role in promoting Eratosthenes' work by serving as a hub for scholars from various disciplines. As chief librarian, he had access to vast resources that enabled him to compile knowledge from different fields, including mathematics and geography. The library facilitated collaboration among scholars, allowing Eratosthenes' ideas on geography to spread and influence future generations, thus solidifying Alexandria's status as a center of learning during the Hellenistic era.
• Evaluate how Eratosthenes' concepts influenced later geographic thought and exploration, particularly in relation to Antioch and Pergamon.
  • Eratosthenes' concepts significantly influenced later geographic thought by establishing foundational ideas about Earth's dimensions and mapping techniques. His work laid the groundwork for future explorers and geographers who would build upon his findings. In cities like Antioch and Pergamon, where knowledge flourished, Eratosthenes' methods inspired further studies in cartography and navigation. This intellectual legacy not only advanced geographic science but also encouraged exploration beyond known territories, shaping how future generations understood their world.

Related terms

Library of Alexandria:

One of the largest and most significant libraries of the ancient world, located in Alexandria, Egypt, that served as a major center for scholarship and learning.

Circumference: The distance around a circle, which Eratosthenes calculated for the Earth, showcasing his skills in geometry and mathematics.

Geography: The study of places and the relationships between people and their environments, which Eratosthenes helped to formalize through his work in mapping and understanding Earth's dimensions.