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Bubble Sextant

Catalogue number:
NASM 1977-2117

Inscriptions:
"BUBBLE CIRCLE SEXTANT" and "G. FELSENTHAL & SONS CHICAGO"

Discussion:
This simple plastic instrument has open sights on one side and a bubble level on the other. The rim is graduated every degree, in four quadrants. It was made for the Navy Bureau of Aeronautics in the mid-1940s, and donated to the Smithsonian in 1972.

Ref: U.S. Navy. Bureau of Aeronautics, Pocket Bubble Sextant (1944 and 1946).

Further Information:

Felsenthal
Aircraft Sextant