Astronomical Quadrant (replica)

Astronomical Quadrant (replica)

Usage conditions apply
In the Almagest (ca. AD 150) Claudius Ptolemy (ca. AD 90 – AD 168) described a "plinth" that could measure the altitude of the noon sun by projecting the shadow of a peg on a graduated arc of 90 degrees. This reconstruction of that instrument was made for exhibition in the National Museum of History and Technology (now the National Museum of American History).
Currently not on view
Object Name
Astronomical Quadrant (replica)
date made
Physical Description
Vermont marble (Vermarco) (overall material)
marble base: 4 in x 56 in x 16 in; 10.16 cm x 142.24 cm x 40.64 cm
instrument: 48 in x 36 in x 6 in; 121.92 cm x 91.44 cm x 15.24 cm
overall: 52 in x 56 3/32 in x 16 in; 132.08 cm x 142.494 cm x 40.64 cm
ID Number
catalog number
accession number
See more items in
Medicine and Science: Physical Sciences
Data Source
National Museum of American History
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