The ancients drew the earth round, and regarded Hellas as the center and Delphi as the center of Hellas, since it had the navel of the earth. Democritus, a man of much experience, first perceived that the earth was oblong, with the length half again the breadth. Dicaearchus the Peripatetic agreed with him. Eudoxus made the length double the breadth, Eratosthenes more than double, Crates semicircular, Hipparchus trapezoid, others . . . , Posidonius the Stoic sling-shaped and wide in the middle from south to north, narrow to the east and west, wider, however, to the southeast, toward India.

Boundaries of the continents: of Europe and Libya the Pillars of Hercules; of Libya and Asia the Nile, but some say the isthmus between Lake Serbonis and the Arabian gulf; of Asia and Europe the ancients said the Phasis River and the isthmus to the Caspian, the later and more recent ones say Lake Maeotis and the Tanais River.