ISOGONIC LINES (Gr. ἰσογώνιος, equiangular), lines connecting those parts of the earth’s surface where the magnetic declination is the same in amount (see Magnetism, Terrestrial).
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ISOGONIC LINES (Gr. ἰσογώνιος, equiangular), lines connecting those parts of the earth’s surface where the magnetic declination is the same in amount (see Magnetism, Terrestrial).