EN
The goal of the current study is to show the usefulenes as source material of a manuscript by Karol de Perthees which presents the method used in compiling his detailed maps of particular provinces of Poland. In the manuscript, the cartographer presented his plan of work on the detailed maps and he described the methods thanks to which a certain degree of precision could be obtained in compiling maps on the basis of itineraries and accounts. The procedure used by de Perthees in his work is evident from the points which he used to summarize it: - On the division of the country in the detailed maps; - Details on the maps of provinces and districts; - On roads in general and on detailed distances from one place to another; - How to correct mistakes and supplement missing information; - On astronomical observations; - Interesting and useful details which can be added to maps of districts; - Notation to be used in the detailed maps. The manuscript is of great value as a source material for historical-geographical research, for it makes it possible to reconstruct successive stages in the drawing of de Perthees's maps.