Principal facts of the earth's magnetism and methods of determining the true meridian and the magnetic declination. Reprinted from the United States magnetic declination tables and isogonic charts for 1902 (1909)
U.S. Coast and Geodetic Survey · Washington Govt. Print. Off · leaf 78
PRIXCIPAL FACTS OF THE EARTHVS MAGNETISM. 63 example, an agonic line (line of no magnetic declination) and follow its various trans-formations from period to period. Or let him compare the chart of 1600 with that of1905, given later, and notice what a complete reversal there has been in the…
Magnetism, Terrestrial
Internet Archive · Gerstein Library, University of Toronto · Public Domain Mark 1.0. Free to use for anything.
