Ripley Octant

This octant has a rosewood frame, flat brass index arm, and ivory name plate. The ivory scale is graduated every 20 minutes from -5° to +95° and read by vernier to 2 minutes of arc. Caroline (Mrs. Alfred E.) Bates, a Washington socialite, gave it to the Smithsonian in 1916.
The inscription reads "Made by Thos Ripley London For Frans Earle July 21st 1784." Thomas Ripley was in business from 1765 to 1790, offering mathematical and optical instruments.
Ref: Gloria Clifton, Directory of British Scientific Instrument Makers 1550-1851 (London, 1895), p.233.
Currently not on view
Object Name
date made
Ripley, Thomas
Physical Description
wood (case material)
place made
United Kingdom: England, London
ID Number
catalog number
accession number
Measuring & Mapping
See more items in
Medicine and Science: Physical Sciences
Data Source
National Museum of American History, Kenneth E. Behring Center
Credit Line
Caroline E. Bates

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