DEPARTMENT OF TERRESTRIAL MAGNETISM. 315 



encircling the globe, as also practically the same procedure with regard to the 

 hourly tabulations, will be followed. 



In order to furnish to those observatory directors who prefer mean 60- 

 minute ordinates beginning with the interval 0^30'°-1^30'", G. M. T., for 

 a limited number of days, as for example, the so-termed international five 

 quiet days each month, these data will likewise be given in the Department's 

 publications. 



It has furthermore been decided, in accordance with the principle to keep 

 observational means and manipulations as simple as possible, to register, as 

 is done at the vast majority of observatories, changes in decUnation (D), 

 in horizontal intensity (H), and in vertical intensity (Z) instead of changes 

 in the three rectangular intensity components {X,Y,Z), all of which are subject 

 to temperature changes. It has been found very helpful to have at least one 

 magnetograph record (D) not affected by temperature changes, and so im- 

 mediately available. 



The cruises of the Carnegie. L. A. Bauer. World's Work, vol. 39, No. 3, 280-301 (Jan. 



1920). (A popular account of the cruises and work of the Carnegie up to 1920. 



The article contains numerous illustrations pertaining to the vessel, instru- 

 ments, cruises, ports, etc.) 

 R6sum^ of observations concerning the solar ecUpse of May 29, 1919, and the Einstein 



effect. L. A. Bauer. Science, n. s., vol. 51, No. 1317, 301-311 (March 26, 



1920). 

 Preliminary results of analysis of light deflections observed during the solar eclipse of 



May 29, 1919. L. A. Bauer. Science, n. s., vol. 51, No. 1328, 581-583 



(June 11, 1920). 

 Further results of analysis of Ught deflections observed during the solar eclipse of May 29. 



1919. L.A.Bauer. Science, n. s., vol. 52, No. 1337, 147 (Aug. 13, 1920). 

 Concerning results of Observed Gravitational Light Deflections.^ Louis A. Bauer. 



The results of the light defltections observed by the British expedition at 

 Sobral, Brazil, during the total solar eclipse of May 29, 1919, as derived 

 from Crommelin's 7 photographic plates, using a 4-inch lens of 19-foot focus 

 and an 8-inch coelostat, gave a deflection at the Sun's limb of 1''98, or about 

 14 per cent higher than the value (1''74) derived from the Einstein theory of 

 gravitation. Resolving the pubhshed deflections in right ascension and dec- 

 lination, for each of the 7 stars concerned, into two components, one along 

 the radius vector to the center of the Sun, the radial component, and the other 

 transverse to the radius vector, the non-radial component, it was noted in- 

 dependeatly by Dr. Silberstein and the author that the observed total 

 deflections were not strictly radial, the non-radial components being of ap- 

 preciable magnitudes and varying in a strikingly systematic manner from 

 star to star. The observed deflection appeared to be a function not simply 

 of distance alone, as required by the Einstein law, but also of the star's 

 position-angle. 



With the view of determining the possible bearing upon the observed 

 Ught deflections of the geophysical obsei'vations made by the expeditions 

 of the Carnegie Department of Terrestrial Magnetism at Sobral, Brazil, and 

 Cape Palmas, Liberia, and by the Brazilian expeditions at Sobral, an analysis 

 was undertaken by the Department of Terrestrial Magnetism. It may be 

 recalled that the question was raised and discussed in Nature, by various 

 British investigators, whether there might not be appreciable abnormal 

 refraction effects in the Earth's atmosphere as caused by meteorological 

 changes during totahty. 



^Presented in the author's absence by Dr. Frederick Slocum at the meeting of the American 

 Astronomical Society, September 3, 1920. 



