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Octant

Catalogue number:
PH*326111

Inscriptions:
"Spencer Browning & Rust London" and "SBR"

Dimensions:
radius 13.75 inches

Discussion:
This octant has an ebony frame and flat brass index arm. The ivory scale is graduated every 20 minutes from -2^o to +99^o40' 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^o. This instrument was probably made around 1800. It belonged to Mount St. Mary’s College in Emmitsburg, Md.

Further Information:

Spencer, Browning & Rust
Octant