296 T. TiiRAPA and T. Matuzawa 



The use of Eotvos's gravity variometer has also been contemplated 

 by the Geodetic Committee and entrusted to the able hands of Messrs. 

 Shinjo, Matsuyama and I. Yamamoto of the Kyoto Imperial University. 

 The results of observations made in the Jaluit Atoll in the Pacitic/^^ 

 the Volcano ^alcnrazima/^^ the Tone liiver Basin^^^ near Tokyo, the 

 Niitu Oil FiekF'^ near Niigata, and the Fushun Colliery^^^ in Manchu- 

 ria, have already been reported and have brought out many points of 

 interest. In the course of these works Matsuyama elaborated the methods 

 of observation and reduction in many respects, working with meticulous 

 care on every source of error both experimental and theoretical. His 

 results in Jaluit and Fushun have shown remarkable regularity in the 

 distribution of the differential coefficients of cj which he succeeded in 

 bringing to fair agreement with the results of theoretical calculations 

 based on some plausible assumptions with respect to the geological 

 structure of the terrains concerned. The result of I. Yamamoto's 

 observations on the Tone Basin have also been revelant in many respects 

 regarding the mass distribution of the region. Niitu Oil Field show- 

 ed an anomalous irregularity in the form of the geoid which suggests 

 the existence of its counterpart in the mass distribution under the tield. 



The results of the investigation on the deviation of the plumb 

 line in the region near Tokyo, carried out under the auspices of 

 the Geodetic Committee have recently been summarized by T. Matu- 

 kuma,^^^ and these will be of much interest for the seismologist, 

 especialy with respect to the Kwanto Earthquake. 



Rebeur Paschwitz's horizontal pendulum for registering the tilting 

 of the crust relative to the direction of gravity has been installed in 

 the Kaniigamo Observatory, and observations carried out by Shida and 

 his assistants since Feb. 1910. In spite of the considerable distance 

 of the station from the sea, the tilting dae to the tidal load was 

 remarkable compared with the component due to the variation of the 

 level directly derivable from the tide-generating potential, so that the 

 difficulties to bo overcome in analysing the different components were 

 considerable. For instance, he had to take account of the actual 



(1) Mem. Kyo., 3 (1918), 17. 



(2) An abstract, T.S.B.K., 9 ^1917), 103. 



(3) Eep. Imp. Jap. Geod. Comm., 3 (1923). 



(4) Kep. Imp. Jap. Geod. Comin., 5 (1924). 



(5) Jap. J. Astr. Geophys., 2 (1924), 91. 



(6) Jap. J. Astr. Geophys., 2 (1924), 1. 



