June 1906 Issue [Article] Terrestrial magnetism Download PDF Adjust Share by Cyrus C. (Cyrus Cornelius) Adams, This article is only available as a PDF to subscribers. Download PDF Tags Discoveries in science Geomagnetism Geophysics History Magnetic declination Observations Secular variations More from Cyrus C. (Cyrus Cornelius) Adams Maps and map-making The Sargasso Sea Unexplored regions of the earth Adjust Share