Illuminating Sixteenth-century Measuring Methods and Map Design: New Findings from Pieter Pourbus’ Chorographic Maps

A new analysis of Pieter Pourbus’ sixteenth-century chorographic maps reveals unprecedented evidence of triangulation techniques, directly linking his cartographic methods to those described by Gemma Frisius. Traces such as compass circles, perforations, and incised meridians on the map of Cadzand suggest a systematic approach to mapping that aligns with Frisius' step-by-step method. Additionally, features like squaring grids and pounced dots provide further insight into Pourbus’ processes for compiling and copying maps. This study, integrating macroscopic examination with GIS analysis, challenges the contested use of triangulation in sixteenth-century cartography and offers a clearer understanding of the period's mapping techniques.

Trachet, J. (2024). Illuminating Sixteenth-century Measuring Methods and Map Design: New Findings from Pieter Pourbus’ Chorographic Maps. The Cartographic Journal, 61(1), 5–26. https://doi.org/10.1080/00087041.2024.2366002