Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock () or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

pl23_theb1632.jpg

Image

Download ( 683 KB )

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

Keywords

Geodesy

Triangulation

Lights

Helio