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![Octant with simple artificial horizon in the form of a pendulum theb2175.jpg Octant with simple artificial horizon in the form of a pendulum](/sites/default/files/styles/max_1300x1300/https/s3.amazonaws.com/s3-east-testmedia-noaa.woc.noaa.gov/dam/Photos/legacy/pl23_theb2175.jpg?itok=Stq6x0RV)
Description
Octant with simple artificial horizon in the form of a pendulum
Collection
Historic Coast & Geodetic Survey
Keywords
Navigation
Astronomic
Visual
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