Isodynamic, Isoclinic, and Isogonic Lines (Gr. isos, 'equal;'; dynamis, 'force;'; klinō, 'I bend;'; gonia, 'an angle'), or lines of equal force, equal inclination, and equal declination, are three systems of lines, which being laid down on maps represent the magnetism of the globe as exhibited at the earth's surface in three classes of phenomena, the varying intensity of the force, the varying dip or inclination of the needle, and its varying declination from the true meridian. See MAGNETISM.
Isodynamic, Isoclinic, and Isogonic Lines
Chambers's Encyclopaedia, Volume 6: Humber to Malta, p. 236
Source scan(s): p. 0249