TERRESTRIAL MAGNETISM. DISTRIBUTION OF THE MAGNETIC DECLINATION IN THE UNITED STATES FOR JANUARY 1, 1910 por Faris, R. L - 1911

Washington: Government Printing Office, 1911. Special Publication 9. With Isogonic Chart and Secular Change Tables."Since the publication fo the isogonic chart of the United States for 1905, so much additional data have been accumulated and the secular change of the magnetic declination has undergone such material modification that a new chart is demanded. January 1, 1910, was selected as the epoch for the chart, in order that the reduction fo the obervations to that epoch might be based on actual observations of the secular change." 14 pp. Large foldout colored map of the U.S. showing Lines of Equal Magnetic Declination and of Equal Annual Change for 1910. tan wraps. Mildly soiled. two rubbed lines on front cover. ex-mus. numbers. Overall Covers are Good+ to Very Good-. ex.mus. stamp on title page, otherwise interior is tight, clean and VG+. . Soft Cover. Good+. Illus. by Tables, Foldout Colored Map,. Size: Approx. 7 3/4" x 11 1/4". U.S. Coast and Geodetic Survey.