pl23_theb1311.jpg
Description
Chart showing isogonic lines for year 1900.Isogonic lines are lines of equal declination
Collection
Historic Coast & Geodetic Survey
Keywords
Geophysics
Geomagnetism
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.