Lecture 04: Measuring the Earth
What is the shape and size of the Earth? This lecture traces historical\nideas about the shape of the Earth, from ancient ideas of a Flat-Earth\nto Aristotle's compelling demonstrations in the 3rd century BC that the\nEarth was a sphere. We then discuss two famous classical measurements\nof the circumference of the Earth by Eratosthenes of Cyrene in the 3rd\ncentury BC and Claudius Ptolemy in the 2nd century AD. Recorded 2007\nSep 24 in 1000 McPherson Lab on the Columbus campus of The Ohio State\nUniversity.