Tracks of Chief Vessels on Which Magnetic Observations Were Made in the Atlantic Ocean, 1839-1915. 



Galilee, 1908 (Pacific) - 



Carnegie, 1909-1915- 



Erebus and Terror, 1839-1843 Carnegie, 1916-1917 (projected) 



Novara, 1357-1860 ..<•• Challenger. 1872 1876 



Gauss, 1902-1903 Discovery, 1902-1904 



Cluett. 1914 _ 



Gazelle,' 1874-1876* • • ' * »— 



Coast and Geodetic Survey, 1903-1915 "'*' •' 



