Bernhard Jenny and Peter Mesenburg:
MapAnalyst – analysis and visualisation of the planimetric accuracy of the Mappa critica published by Tobias Mayer (1750)
Cartographica Helvetica 43 (2011) 43–48
MapAnalyst is a software application for the analysis of the planimetric accuracy of old maps. It allows the generation of distortion grids, error vectors and isolines of equal scale and orientation. In addition, MapAnalyst computes the scale and the rotation of the old map, as well as statistical indices that describe the map's geometrical accuracy. The open-source software provides a user-friendly graphic interface, and is available for all important computer platforms free of charge from the MapAnalyst site.
Using Johann Tobias Mayer's Mappa critica, published in 1750 as an example, this article illustrates the generation of various visualisations. The Mappa critica visually illustrates the poorer accuracy of two older maps that were published at the beginning of the 18th century. An evaluation of Tobias Mayer's criticism of the maps by Delisle (1701) and Homann (around 1705) requires an assessment of the positional accuracy of Mayer's map, which is the purpose of this article.