Spencer, Browning & Rust Octant

Description
This octant has an ebony frame and flat brass index arm. The ivory scale is graduated every 20 minutes from -2° to +99° 40' and read by vernier with tangent screw 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°. The "Spencer Browning & Rust London" and "SBR" inscriptions refer to a firm that was in business from 1784 to 1840. This instrument belonged to Mount St. Mary’s College in Emmitsburg, MD.The design suggest that it was made around 1800.
Location
Currently not on view
date made
ca 1800
maker
Spencer Browning & Rust
place made
United Kingdom: England, London
Physical Description
ebony (overall material)
brass (overall material)
ivory (overall material)
Measurements
box: 12 cm x 43.2 cm x 37.5 cm; 4 23/32 in x 17 in x 14 3/4 in
octant radius: 13 3/4 in; 34.925 cm
overall in box: 4 3/4 in x 14 1/2 in x 16 5/8 in; 12.065 cm x 36.83 cm x 42.2275 cm
ID Number
PH.326111
catalog number
326111
accession number
257245
Credit Line
Mount St. Mary's College
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Data Source
National Museum of American History, Kenneth E. Behring Center

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