Sphérique et sphéropée en Grèce ancienne

Abstract

In ancient Greece, astronomy and geography were closely connected. Geography was based on the teachings of astronomy, but it determined them as well: for example the needs of scientific geography forced astronomers to use geocentric hypotheses. To study the relationship between a motionless earth situated in the central part of the cosmos and a sky moving in a circle round the axis of the world, two methods were available, either the geometrical method, used more particularly in the selection called Small Astronomy (Autolycos, Euclid, Theodose of Bithynia) or the experimental approach, dealing with reduced representations of the world, more or less precise (celestial globes or armillary spheres). The first method was supported by Spheric, or Geometry of the sphere; the second resorted to Spheropoeia, a branch of Mechanics. There was mutual interaction between these two methods.