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Octant

Catalogue number:
PH*39391

Inscriptions:
"SPENCER, BARRETT & C^O LONDON"

Dimensions:
radius 9.75 inches

Discussion:
The Smithsonian received this octant from the U.S. Nautical Almanac in 1882. It was made in the mid-nineteenth century. It has an ebony frame, reinforced brass index arm, and ivory scale. The scale is graduated every 20 minutes from -3^o to +109^o and read by vernier with tangent screw to single minutes of arc.

Further Information:

Octant