09.25.2006 - By Richard Pogge
What is the shape and size of the Earth? This lecture traces historical
ideas about the shape of the Earth, from ancient flat-Earth models to
the compelling demonstrations by Aristotle in the 3rd century BC that
the Earth was a sphere. We then discuss ways people measured the size
of the Earth, describing the results of Eratosthenes of Cyrene in the
2nd century BC and Claudius Ptolemy in the 2nd century AD, and their
impact. Recorded 2006 Sep 25 in 100 Stillman Hall on the Columbus
campus of The Ohio State University.