The Ni A, Zeiss's first precise level suitable for first order geodetic work, was produced
during the years 1935-1941. This example may be one of the many instruments that American intelligence officers captured from the German geodetic office at the end of World War II. The United States National Imagery and Mapping Agency transferred it to the Smithsonian in 2000.
Ref: P. Werkmeister, "Ein neues Nivellier instrument von Carl Zeiss für feinste
Hoehenbestimmungen," Zeitschrift für Instrumentenkunde 57 (January 1937): 25
Carl Zeiss, Instructions for the Use and Adjustment of the Zeiss Precision Level A (Jena,