Eratosthenes
He accurately calculated the circumference of the Earth using geometric principles and observations of shadows.
Most quoted
"Give me a lever long enough and a fulcrum on which to place it, and I shall move the world. (Often attributed to Archimedes, but Eratosthenes was also known for similar sentiments regarding the power of measurement and calculation)"
— from Public Address
"To understand the world, one must first measure it. Measurement is not just about numbers; it is about defining boundaries, understanding relationships, and ultimately, comprehending our place within the vastness."
— from Inferred from his scientific methodology
"The Earth is a sphere, and its circumference can be measured. This knowledge, though seemingly practical, reveals the order and the measurable nature of the cosmos, hinting at a deeper, underlying truth."
— from Inferred from his work on Earth's circumference
All quotes by Eratosthenes (354)
The sun is so far from the earth that its rays are practically parallel when they reach us.
One should not trust the stories of those who speak of a sea beyond the inhabited world, for they are fables.
Geography is the drawing of the inhabited world as we know it.
The three continents [Europe, Asia, Libya] are surrounded by sea.
The Nile flows from the mountains of the south, from lakes which are fed by the rains of the torrid zone.
The Caspian is a gulf of the Northern Ocean.
The Red Sea is a gulf of the Ocean which stretches from the south into our inhabited world.
India is bounded on the east by the Eastern Ocean, and on the south by the Great Sea.
The Pillars of Hercules are the limits of the inhabited world from the west.
The distance from the Pillars to the Gulf of Issus is 70,000 stades.
The earth is divided into five zones: the torrid, two temperate, and two frigid.
The Arctic Circle is the limit of the northern temperate zone.
The Antarctic Circle is the limit of the southern temperate zone.
The equator divides the torrid zone in two.
The sun is vertical over the equator twice a year.
The obliquity of the ecliptic is the cause of the seasons.
The length of the longest day at the summer solstice is used to determine latitude.
Meroë is under the summer tropic.
The distance from Meroë to Alexandria is 10,000 stades.
The distance from the equator to the pole is 252,000 stades, a quarter of the earth's circumference.
Contemporaries of Eratosthenes
Other Astronomys born within 50 years of Eratosthenes (-276–-195).