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pl23_theb1633.jpg

Signaling with heliograph near Monument 92

Image

Download ( 538 KB )

Permalink

https://www.noaa.gov/media/digital-library-photo/pl23theb1633jpg

Description

Signaling with heliograph near Monument 92.Alaska - Canada border.International Boundary Commission

Display Date

1910

Location

Alaska - Canada Boundary

Collection

Historic Coast & Geodetic Survey

Geodesy

Triangulation

Heliotropes & Signal Lamps

Keywords

Geodesy

Triangulation

Lights

Helio