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pl23_theb1632.jpg

Image

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Permalink

https://www.noaa.gov/media/digital-library-photo/pl23theb1632jpg

Description

Heliograph at Station 22.Alaska - Canada border.International Boundary Commission

Display Date

1911

Location

Alaska - Canada Boundary

Collection

Historic Coast & Geodetic Survey

Geodesy

Triangulation

Heliotropes & Signal Lamps

Keywords

Geodesy

Triangulation

Lights

Helio