Cartographic manuscript intended to teach engineer-geographers how to (in the authors words) "centrer les angles " (bisect angles?) and to triangulate to calculate locations on a map as precisely as possible. The author, remains unidentified but probably taught cartography. He (the field was hardly open to women) gives many examples to explain his methods, all richly illustrated in the manuscripts geometric figures and with tables. He quotes the methods of the important French mathematician, physician and hydrographer Pierre Bouguer (1698-1758), who was also geometer at the Académie des Sciences in Paris, for the means to "centrer les angles" (though we have not found Bouguer using that phrase) and those of the French astronomer and cartographer César-François Cassini de Thury (1714-1784), also member of the Académie, for triangulation. Altogether the work is a practical guideline for engineer-geographers, in which the author not only describes methods for bisecting(?) angles and for triangulation, but for example also how to use his own tables on pp. 29-44. A highly interesting cartographic manuscript with a strong geometrical focus quoting two of the foremost French cartographers of the 18th century.
With the library stamp of the Danish national library (Det Kongelige Bibliothek) in Copenhagen. Portfolio a little worn, dust-soiled and somewhat stained, but the leaves are still in good condition. Katalog der Bibliothek und Kartensammlung der Königlichen Allgemeinen Kriegsschule (1851), 56.