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![Ancient text demonstrating use of cross-staff theb2173.jpg Ancient text demonstrating use of cross-staff](/sites/default/files/styles/max_1300x1300/https/s3.amazonaws.com/s3-east-testmedia-noaa.woc.noaa.gov/dam/Photos/legacy/pl23_theb2173.jpg?itok=O-VhcjSe)
Description
Ancient text demonstrating use of cross-staff
Collection
Historic Coast & Geodetic Survey
Keywords
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