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![A heliotroper at Mount Margaret triangulation station just north of Spirit Lake theb4107.jpg A heliotroper at Mount Margaret triangulation station just north of Spirit Lake](/sites/default/files/styles/max_1300x1300/https/s3.amazonaws.com/s3-east-testmedia-noaa.woc.noaa.gov/dam/Photos/legacy/pl23_theb4107.jpg?itok=Mc5L7l2P)
Description
A heliotroper at Mount Margaret triangulation station just north of Spirit Lake.
Location
Washington, Mount Margaret
Collection
Historic Coast & Geodetic Survey
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