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 28
r discovery. The necessity for measuriyig the angle of pointing of theneedle thus became apparent in 14.92., and hence this must be regarded as the year of birthof the science of t^errestrial inagnctisni. 7vhich has for its special object the measure7nent ofthe earth^s tnagnetic elements. Discovery… … Fig. 5.—Compass sun-dial sliowiny earliest magnetic declination at Paris (1541). astronomical meridian and not the discovery of Columbus, of which nothing appearedin print. In the early part of the sixteenth century the quaint old German town ofNuremburg was quite a center for the manufacture of…
Magnetism, Terrestrial
Internet Archive · Gerstein Library, University of Toronto · Public Domain Mark 1.0. Free to use for anything.
