DEPARTMENT OF TERRESTRIAL MAGNETISM. 303 



the Earth by 20 per cent; electric storms which disturb instantly 

 telegraphic and telephonic communications and give rise to other 

 marked disturbances. 



PUBLICATION WORK. 



The manuscript was completed for volume 2, Researches of the 

 Department of Terrestrial Magnetism, bearing the title "Land Mag- 

 netic Observations 1911 to 1913 and Reports on Special Researches, 

 by L. A. Bauer and J. A. Fleming." This volume contains the results 

 of the magnetic observations made by the land expeditions during the 

 three years 1911-1913, at 978 stations distributed over 57 countries 

 and island-groups, in all parts of the Earth. The previous volume 

 contained the results of the land magnetic observations 1905-1910, 

 The publication of the land results has thus been brought up to 1914. 



The manuscript for volume 3, to contain the final results of all the 

 ocean work, 1905-1913, is in good state of progress, and it is hoped 

 that the volume may appear in 1915. 



The reports on special researches given, as mentioned above, in 

 volume 2 comprise: Description of research buildings of the Depart- 

 ment of Terrestrial Magnetism, by L. A. Bauer and J. A. Fleming; 

 magnetic inspection trip and observations during total solar eclipse 

 of April 28, 1911, at Manua, Samoa, by L. A. Bauer; results of inter- 

 national comparisons of magnetic standards, 1905-1913, by L. A. 

 Bauer and J. A. Fleming. 



There have also appeared in various journals during the year 15 

 articles, and several are in preparation, by Messrs. Armstrong, Ault, 

 Bauer, Duvall, Hewlett, Kidson, Peters, and Swann; the subjects 

 covered are atmospheric electricity, general physics, mathematics 

 (methods of seeking hidden periodicities), solar and terrestrial magnet- 

 ism. (See Bibliography, pages 40-49, and Abstracts.) 



TERRESTRIAL MAGNETISM. 



Besides the publication work already mentioned and the instrumental 

 work described below, investigations of various kinds are in progress. 

 The interesting question as to the cause of the observed equatorial 

 increase in the intensity of the Earth's apparent magnetization, as 

 announced in the report for the fiscal year 1911-1912, has received 

 renewed attention. The fact that there is such an increase in the 

 equatorial regions has now been verified in various ways. 

 • The Director has furthermore completed a preliminary study, the 

 results of which were presented before the recent meeting of the 

 Astronomical and Astrophysical Society, entitled "On the solar 

 radiation and terrestrial magnetism."^ 



'Published in Terrestrial Magnetism, September 1914, pp. 113-125. 



