The 1:50,000 Michaelis map of Aargau canton, 1837–1849
Cartographica Helvetica 3 (1991) 2–13
Around 1800 the only complete maps of the Aargau canton were to be found firstly in the Atlas Suisse by Meyer and Weiss, and secondly on a sheet by Scheurmann. Both maps were in the 1:120,000 scale. This situation did not change until Guillaume Henri Dufour needed exact geodetic and topographic surveys for his Topographic Map of Switzerland.
Ernst Heinrich Michaelis turned out to be just what the Aargau canton needed, even though he was not a surveying engineer but an army captain from Germany. He started his work in 1837 with the 3rd order triangulation (geodetic survey) of the canton, followed by a detailed topographic survey. Michaelis and his assistants sketched the terrain in 43 field books whose pages were lined with a unique rhomboid pattern. The fair drawing was done multi-colored on 18 sheets of different sizes at the 1:25,000 scale. It was unusual that Dufour did not insist on contour lines but allowed Michaelis to represent the topography with hachures.
The cantonal government decided to publish a general map of the canton already a year before the topographic survey was even completed. The engraving draughts at the 1:50,000 scale were established from 1842 to 1845. Michaelis supervised the engraving of the monocoloured, very fine-lined map on four copper plates by Delsol and Hacq in Paris, which lasted from 1845 to 1848. It is interesting to note that the plates were copied by Schöninger in Munich using the method of galvanization invented shortly before (1837).