54 



POLAR PROBLEMS 



Since the publication of Mr. Jones's chart considerable additional 

 information in the Arctic has become available. Thus we have now 

 the results of the magnetic observations made by Captain Amundsen's 



y, ,ip~7E 



NAVIGATIONAL CHART 

 OF the; 



ARCTIC BASIN 



PREPARED FOR <% 



THE DETROIT AVIATION SOCIETY "^ 



Fig. I — Air navigational chart of the Arctic Regions north of 70° N. latitude, vi'ith approximate 

 lines of equal magnetic declination (variation of the compass) for 1926, revised from data supplied by 

 the Department of Terrestrial Magnetism, Carnegie Institution of Washington. Scale, 1:40,000,000. 

 See also Fig. 2. 



Maud expedition, 1922-1925, for the region between Siberia, Bering 

 Strait, and the New Siberian Islands, and by the three MacMillan 

 expeditions, 1921-1925, to Bafifin Island and Greenland.* Also, the 



* The report on the magnetic and electric observations made by the Maud expedition will be 

 published by the Carnegie Institution of Washington in a forthcoming volume (Vol. 6) of its Publica- 

 tion No. 175, "Researches of the Department of Terrestrial Magnetism." The magnetic records of 

 the MacMillan expeditions of 1921-1922 to Bafifin Island and of 1923-1924 to Northern Greenland 

 are in the files of the Department; the results of the field observations will appear in Vol. 6 of the pub- 

 lication just cited, and the results of the observatory observations will be published in a subsequent 

 volume. The magnetic records of the MacMillan expedition to Greenland, 1925, are in the files of the 

 U. S. Coast and Geodetic Survey; the results have been published in D. L. Hazard: Results of Mag- 

 netic Observations Made by the United States Coast and Geodetic Survey in 1925, U. S. Coast and 

 Geodetic Survey Spec. Publ. No. 125, Washington, 1926; reference on p. 13. 



