Octant

Description
This octant has an ebony frame, and flat brass index arm with floral design. The ivory scale is graduated every 20 minutes from -5° to +95° and read by vernier with tangent screw to 2 minutes of arc. There is also a back sight and a back horizon glass that can be used to measure angles greater than 90°. This instrument was probably made in the late eighteenth century. It belonged to the College of the Holy Cross in Worcester, Ma.
Location
Currently not on view
Measurements
radius: 17 3/4 in; 45.085 cm
overall: 3 in x 16 1/8 in x 19 3/16 in; 7.62 cm x 40.9575 cm x 48.73625 cm
ID Number
PH.326931
catalog number
326931
accession number
264083
Credit Line
College of the Holy Cross
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Data Source
National Museum of American History, Kenneth E. Behring Center

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