The length of coastlines in Ptolemy's<i>Geography</i>and in&amp;#160;ancient&amp;#160;<i>periploi</i>
Journal: History of geo- and space sciences
Year: 2018

Abstract. The lengths of the coastlines in Ptolemy's Geography are compared with the corresponding values transmitted by other ancient sources, presumably based on some lost periploi (literally "voyages around or circumnavigations", a genre of ancient geographical literature describing coastal itineraries). The comparison reveals a remarkable agreement between them, suggesting that Ptolemy relied much more heavily on these or similar periploi than it used to be thought. Additionally, a possible