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![Signal pole with flag and tin cone for reflecting sunlight theb2461.jpg Signal pole with flag and tin cone for reflecting sunlight](/sites/default/files/styles/max_1300x1300/https/s3.amazonaws.com/s3-east-testmedia-noaa.woc.noaa.gov/dam/Photos/legacy/pl23_theb2461.jpg?itok=eOVrHpgw)
Description
Signal pole with flag and tin cone for reflecting sunlight.Epping Plains area of Maine (Image credit: NOAA Central Library)
Credit
NOAA Central Library
Display Date
1857
Collection
Historic Coast & Geodetic Survey
Geodesy
Triangulation
Wooden Towers & Signal Poles
Keywords
Geodesy
Triangulation
Towers
Wooden