Size of Earth and the Antipodes
In his thesis The origins of antipodal theory (see below for details), Schiöth gives a useful summary of the history of measuring the earth's size.
Calculating the size of the earth
The first known calculation in the extant literature of the circumference of the earth might be derived from Eudoxus. In On the Heavens (298b), Aristotle attributes the figure of 400,000 stades for the circumference of the earth, to unknown 'mathematicians.' Due to Eudoxus’s known influence on Aristotle’s astronomy, some scholars have pointed out that in this passage Aristotle might be referring to Eudoxus.Value of the stade:
The stade (στάδιον or stadion) was an ancient Greek unit of measurement, ‘in origin the distance covered by a plow in a single draft, consisted of 600 Greek feet; but the length of a foot was subject to some local variation in the Greek world’ (Harley & Woodard, 1987, p …