Octant

Description
This octant has a mahogany frame and index arm. The boxwood scale is graduated every 20 minutes from 0° to 90° and read by transversals to 2 minutes of arc. An inscription penciled on the back of the scale reads: "Capt. Rowland Thompson = Lewes = Delaware 1792." A descendant donated it to the Smithsonian in 1882.
Location
Currently not on view
Object Name
octant
date made
ca 1792
Measurements
radius: 20 in; 50.8 cm
overall: 22 1/4 in x 18 5/8 in x 3 1/2 in; 56.515 cm x 47.3075 cm x 8.89 cm
ID Number
PH*308473
catalog number
308473
accession number
93249
subject
Measuring & Mapping
Navigation
See more items in
Medicine and Science: Physical Sciences
Navigation
Data Source
National Museum of American History, Kenneth E. Behring Center
Credit Line
George Andrews Thompson
Additional Media

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