pl23_theb1633.jpg
![Signaling with heliograph near Monument 92 theb1633.jpg Signaling with heliograph near Monument 92](https://s3.amazonaws.com/s3-east-testmedia-noaa.woc.noaa.gov/dam/Photos/legacy/pl23_theb1633.jpg)
Description
Signaling with heliograph near Monument 92.Alaska - Canada border.International Boundary Commission
Display Date
1910
Location
Alaska - Canada Boundary
Category
Historic Coast & Geodetic Survey
Geodesy
Triangulation
Heliotropes & Signal Lamps
Keywords
Geodesy
Triangulation
Lights
Helio