Lessons in practical electricity; principles, experiments, and arithmetical problems; over four hundred illustrations; an elementary text book (1909)
Swoope, C. Walton (Coates Walton), d. 1901 · New York, D. Van Nostrand company · leaf 63
d isogonic lines. They correspond with the meridiansof longitude, but are also irregular. Such maps are preparedfrom time to time by the United States Geodetic Survey, andare used in determining localities, especially in connectionwith the mariners compass on board ships. 54. The Mariners… … EA R TH 5 MA QNETISM. 45
Electricity · Magnetism
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
