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Usage conditions apply
This is a cherry bar with folding brass sights located near either end and centered on one beveled edge. The other beveled edge is graduated to quarter inches. The U.S. Geological Survey transferred it to the Smithsonian in 1907.
Currently not on view
Object Name
Physical Description
wood (overall material)
brass (overall material)
overall: 2 3/4 in x 23 in; 6.985 cm x 58.42 cm
overall arms folded down: 11/16 in x 23 in x 1 7/8 in; 1.74625 cm x 58.42 cm x 4.7625 cm
ID Number
catalog number
accession number
Credit Line
U.S. Geological Survey
See more items in
Medicine and Science: Physical Sciences
Measuring & Mapping
Surveying and Geodesy
Data Source
National Museum of American History
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