Blunders,Errors and Entanglements: Scrutinizing the Cantino Planisphere with a Cartometric Eye

ABSTRACT

The results of a cartometric analysis of the early sixteenth-century Portuguese chart of the world known as the Cantino planisphere are presented and discussed. The focus is on errors affecting the geographic lines and the representation of the coastlines. The outputs of three types of analyses are considered: a quantitative assessment of scales (scales of latitude and scales of distance); a qualitative evaluation of the implicit grid of meridians and parallels underlying the representation; and an assessment of the accuracy of latitudes. From these, details were obtained about the chart's construction, some contradicting previous interpretations, which allowed connections to be established between the depiction of certain areas on the chart and contemporary voyages of exploration. It is concluded that the geometry of the Cantino planisphere is fully explained by the use of the cartographic methods of the Renaissance once the effect of magnetic declination is taken into account.