292 CARNEGIE INSTITUTION OF WASHINGTON. 



Note on a simple measure of the Earth's daily magnetic activity. Louis A. Bauer, Terr. 

 Mag., vol. 27, 31-34 (March-June 1922). 



In a timely paper^ for the Rome meeting of the International Section of 

 Terrestrial Magnetism and Electricity, Dr. G. van Dijk, of the De Bilt 

 Observatory, made a very desirable comparison, chiefly for the year 1915, 

 of measures of terrestrial magnetic activity proposed by various investigators. 

 Dr. van Dijk's paper is briefly reviewed, and, with the aid of his figures, a 

 graphical comparison is made of the measures of magnetic activity proposed 

 by Bidhngmaier, Chree, Schmidt, Bauer, and van Dijk. 



The limitations of the computing personnel at most of the magnetic obser- 

 vatories require that a measure of magnetic activity be used, preferably of 

 the linear type, which can be readily computed and which will be found to be 

 approximately the same at stations in moderate magnetic latitudes all over 

 the Earth. Studies are in progress to see how satisfactorily measures already 

 used by the writer will fulfill the conditions (see last year's report (1921), 

 p. 349). 



Rome meeting of the International Section of Terrestrial Magnetism and Electricity, May 

 1922.^ Louis A. Bauer. Terr. Mag., vol. 27, 89-101 (September 1922). 



A well-attended meeting of the Section of Terrestrial Magnetism and Elec- 

 tricity of the International Geodetic and Geophysical Union was held at 

 Rome from May 4 to 9, 1922. Representatives from Australia, Belgium, 

 France, Great Britain, Italy, Japan, Norway, Poland, Spain, Sweden, and the 

 United States were present at various sessions. Besides discussion of the 

 Agenda, which contained leading questions pertaining to terrestrial mag- 

 netism and electricity, reports were presented by national and other com- 

 mittees and by leading investigators. 



Professor Tanakadate (Japan) tendered his resignation as president of the 

 section because of his inability to attend to the duties involved. Dr. Charles 

 Chree (Great Britain) was then chosen president and Professor Luigi Palazzo 

 (Italy) vice-president. According to the statutes, the secretary and director 

 of the central bureau. Dr. Louis A. Bauer, continues in office until the next 

 meeting, which will be held at Madrid, Spain, in 1924. Directors J. Jaumotte 

 (Belgium), Ch. Maurain (France), and Professor A. Tanakadate (Japan) 

 were elected additional members of the executive committee. It was agreed 

 that administrative matters should be left to the officers of the section. 



Five committees were appointed: (1) Committee on Magnetic Surveys and 

 International Comparisons of Instruments (Louis A. Bauer, chairman); (2) 

 Committee on Observational Work in Atmospheric Electricity to report on 

 Objects, Instruments, and Methods (G. C. Simpson, chairman); (3) Com- 

 mittee on Measures of Magnetic Characterization of Days; (4) Committee 

 on Best Methods, Instruments, and Compilations for Polar-Light Observa- 

 tions; (5) Committee to Consider and Report on Best Methods and Instru- 

 ments for Earth-Current Observations (Sir Arthur Schuster, chairman). 

 The appointment of chairmen of committees 3 and 4 was deferred, pending 

 the early entrance into the union of additional countries. 



The representatives of the American Geophysical Union on these interna- 

 tional committees are: Louis A. Bauer and N. H. Heck (No. 1); W. F. G. 

 Swann (No.2 ); R. L. Paris (No. 3); J. A. Fleming (No. 4); and S. J. Mauchly 

 (secretary of No. 5). 



> Activity of the Earth's magnetism and magnetic characterization of days, Ned. Med. Inst. 

 No. 102, Utrecht, 1922. 



