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![A Kern collimator for centering the observing tower over the mark geod1076.jpg A Kern collimator for centering the observing tower over the mark](/sites/default/files/styles/max_1300x1300/https/s3.amazonaws.com/s3-east-testmedia-noaa.woc.noaa.gov/dam/Photos/legacy/pl23_geod1076.jpg?itok=j43FyOZM)
Description
A Kern collimator for centering the observing tower over the mark.
Collection
Geodesy
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