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Octant

Catalogue number:
PH*334285

Inscriptions:
"NORIE LONDON"

Dimensions:
radius 9.25 inches

Discussion:
This octant has an ebony frame, reinforced brass index arm, and ivory name plate. The ivory scale is graduated every 20 minutes from -3^o to +100^o and read by vernier with tangent screw to single minutes of arc. There is also a back sight and a back horizon glass that could be used to measure angles greater than 90^o. John William Norie established a Navigation Warehouse in London in 1799. The firm traded as Norie & Co. from 1816-1839.

Ref: Gloria Clifton, Directory of British Scientific Instrument Makers 1550-1851 (London, 1895), p. 201.

Further Information:

Octant