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Octant

Catalogue number:
PH*326931

Dimensions:
radius 17.75 inches

Discussion:
This octant has an ebony frame, and flat brass index arm with floral design. The ivory scale is graduated every 20 minutes from -5^o to +95^o 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^o. This instrument was probably made in the late eighteenth century. It belonged to the College of the Holy Cross in Worcester, Ma.

Further Information:

Octant