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Octant

Catalogue number:
AF*59549-N

Inscriptions:
"Owens Liverpool" and "John Nickels.1797"

Dimensions:
radius 14 inches

Discussion:
This octant has an ebony frame, flat brass index arm, and ivory name plate. The ivory scale is graduated every 20 minutes from -2^o to +99^o and read by tangent screw and vernier to single minutes of arc. There is also a back sight and a back horizon glass that can be used to measure angles greater than 90^o. The Society of Oldest Inhabitants of Washington, D.C. donated it to the Smithsonian in 1968.

Further Information:

Owens
Octant