352 CARNEGIE INSTITUTION OF WASHINGTON. 



solution of some of the outstanding questions. Penetrating, as it will, to a 

 region near the North Magnetic Pole, it is planned, for a period of 8 to 10 

 months, to make continuous and systematic observations, pertaining chiefly 

 to the magnetism of the Earth, the electrical and meteorological condition of 

 the atmosphere, and to polar lights. A sledge trip may also be attempted to 

 the locality of the North Magnetic Pole, supposed to be near the western coast 

 of Boothia Felix, during which a systematic magnetic survey of the region 

 may be undertaken. 



The special instrumental appliances and equipment have been furnished the 

 expedition by the Department of Terrestrial Magnetism of the Carnegie 

 Institution of Washington, and important accessory instruments have been 

 loaned by various government departments — the Weather Bureau, the 

 Signal Corps, the Coast and Geodetic Survey, and the Bureau of Standards. 

 Canadian governmental bureaus have also extended to the expedition cordial 

 cooperation in various ways and have supplied valuable charts and informa- 

 tion. The United States Hydrographic Office has contributed a valuable 

 series of charts. The Department of Terrestrial Magnetism has furthermore 

 given two of the members of the Expedition, Messrs. G. D. Howell jr. and R. H. 

 Goddard, special training at Washington in the proposed scientific work to be 

 carried out in accordance with the instructions and program prepared by the 

 Department. The program of scientific work includes provision for simul- 

 taneous cooperative work with other stations in northerly latitudes estab- 

 lished by various European countries and Canada in conjunction with the 

 Amundsen Arctic Expedition. 



The observations of polar lights will be of special interest. Polar explorers 

 have repeatedly given testimony and have recited experiences which would 

 apparently indicate that the polar-light rays, or beams, pass through the 

 atmosphere and come down comparatively close to the Earth's surface. 

 However, many thousand observations made near the north coast of Norway 

 by a photographic method, similar to the one to be used for the first time in the 

 far North by the MacMillan Expedition, clearly indicate that the rays do not 

 get closer to the Earth than about 60 miles, though they may extend from 

 that level upward hundreds of miles. The MacMillan Expedition will be 

 equipped with photographic appliances for investigating the question as to 

 the depth of penetration into our atmosphere of the auroral beams in polar 

 regions and thus it will be able to make a contribution to our knowledge which 

 will undoubtedly help greatly in establishing a rational theory of polar lights. 



Latest annual values of the ma;?netic elements at observatories. J. A. Fleming. Terr. 

 Mag., vol. 25, 179-181 (December 1920). 



A compilation of the most recent annual values of the magnetic elements 

 at observatories distributed over the Earth. 



The completion of the general magnetic survey of Australia by the Carnegie Institution 

 of Washington. E. Kidson. (Prepared for the meeting of the Aastral- 

 asia Association for the Advancement of Science at Hobart in January 

 1921; also presented later before the Royal Society of Tasmania.) 



This paper was in continuation of one presented by the author at the 

 meeting of the Association held in 1913 at Melbourne, in which the general 

 plan of the survey was explained and some of the earlier results were com- 

 municated.^ The number and distribution of the stations estabUshed by the 

 close of the survey in November 1914 must be considered very satisfactory. 

 The lack of facilities for traveling over large areas in the interior prohibited 



'See "The general magnetic survey of Australia by the Carnegie Institution of Washington," 

 by E. Kidson. Rep. Austral. Assoc. Adv. Sci., Melbourne, vol. 14, 20-23, 1913. 



