270 CARNEGIE INSTITUTION OF WASHINGTON. 



B. Observatory Work: 



Because of the unsatisfactory distribution of magnetic observatories in the Southern 

 Hemisphere, it was considered highly important that the complete program of work in 

 terrestrial magnetism, atmospheric electricity, earth-currents, and allied observations 

 at the two magnetic observatories (Watheroo, Western Australia, and Huancayo, 

 Peru) be fully carried out. Further relations with other geophysical and cosmical 

 phenomena, such as polar lights, "statics," earth-currents, solar activity, etc., may be 

 disclosed. The intensive study of instantaneous, or short-period, perturbations at 

 widely separated observatories, making use of available wireless stations for obtaining 

 the desired accuracy in the time element, was specially recommended. 



C. Laboratory Investigations: 



It was thought essential that laboratory investigations, such as are briefly enumerated 

 under Topic 7, be conducted concurrently with the observational work in the field and 

 at the observatories. Besides the experiments on magnetism in general, now in 

 progress, it was considered desirable to continue the investigations relating to the 

 existence of vertical electric currents and the Earth's precise action on a magnet. The 

 possible effect of high pressure on the critical temperature of magnetization was also 

 considered a problem which may have important bearings on some of the topics. 



D. Theoretical Studies: 



The analyses and theoretical studies outlined under topic 8, it was thought should 

 be vigorously continued. It was suggested in this connection that it would be highly 

 desirable to make provision, as soon as conditions permitted, to add to the Department's 

 staff a well-trained mathematical physicist to assist the Director in his theoretical 

 studies. 



The year's work of the Department was planned, as far as circumstances 

 permitted, to put into effect the conclusions and recommendations of the 

 conference. 



Regarding the personnel of the Department and the duties assigned to 



each member during the year, reference may be made to the summary on 



page 282. 



INVESTIGATIONAL WORK IN WASHINGTON. 



The general investigational work, theoretical and experimental, conducted 

 during the year in the Department's laboratory at Washington by the Divi- 

 sion of Investigational Work, under the Director's charge, was as follows: 



TERRESTRIAL MAGNETISM AND ELECTRICITY.^ 



(1) Line-integrals of the magnetic force. — Additional computations have 

 been made since those reported upon last year bearing upon one of the chief 

 outstanding problems in terrestrial magnetism. The question is whether 

 any appreciable percentage of the magnetic forces observed on the Earth's 

 surface may have to be ascribed to electric currents passing perpendicularly 

 through the surface, from the atmosphere into the Earth, and vice versa, or 

 to some cause whose effects are equivalent to vertical currents and thus 

 cause a slight non-uniformity in the terrestrial magnetic jfield. The results 

 for four large ocean areas inclosed by the Carnegie's tracks 1909-1913, two 

 of the areas being in the North Atlantic Ocean, one in the Indian, and one 

 in the Pacific Ocean, all accord with our previous determinations in regard to 

 the direction and general magnitude of indicated vertical electric currents. 

 They also show a consistent and possibly a significant geographical distribu- 

 tion in magnitude as well as algebraic sign. At the Rome meeting in May 

 of the International Section of Terrestrial Magnetism and Electricity, Sir 

 Arthur Schuster and Sir Frank Dyson informed the Director of similar results 



» From the report of Louis A. Bauer and W. J. Peters. 



