Astronomical Quadrant


This portable astronomical quadrant, which resembles English instruments of the late eighteenth century, has a 12-inch radius, stands 17 inches high, and could be used for measuring star altitudes. It belonged to Andrew Ellicott (1754-1820), a surveyor/geodesist who ran the boundaries of several American states, and who probably made it for his own use. The lenses are original. Andrew Ellicott Douglass added the tangent screw in 1885.

Associated Dates: 1931 10 28 / 1931 10 281899 01 26 / 1899 01 261796 00 00 / 1796 00 00, 1890 00 00 / 1890 00 00

User: Ellicott, Andrew

Location: Currently not on view

Associated Place: United States: Arizona, TucsonUnited States: Arizona, Flagstaff

See more items in: Medicine and Science: Physical Sciences


Exhibition Location:

Data Source: National Museum of American History

Id Number: PH.152081Accession Number: 116914Catalog Number: 152081

Object Name: Astronomical Quadrant

Physical Description: metal, brass (overall material)glass (overall material)original lenses. (container material)Measurements: average spatial: 45.1 cm x 30.5 cm x 24.8 cm; 17 3/4 in x 12 in x 9 3/4 inoverall: 17 5/8 in x 13 1/4 in x 13 3/8 in; 44.7675 cm x 33.655 cm x 33.9725 cm


Record Id: nmah_1132007

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