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Bubble Sextant

Catalogue number:
NASM 1957-636

Discussion:
This sextant has an aluminum frame, and a bubble-type artificial horizon mounted behind the horizon glass. Karl Schwarzschild designed the form around 1910. The National Bureau of Standards transferred this example to the Smithsonian in 1957. The box is marked "N.V. TECHN. MAATSCH^IJ Aërofoto’ Singe 238-Amsterdam."

Ref: K. H. Beij, "Astronomical Methods in Aerial Navigation," Report of the National Advisory Committee for Aeronautics 198 (1924), p. 16.

Further Information:

Schwarzschild
Aircraft Sextant