2 Art. 5. — T. Terada, M. Isimoto and M. luiauiura: 



and pointed out a peculiar fact that the decrease with the latitude 

 is comparatively small in Southern Japan, but remarkable in the 

 Northern, the dependency being quite different from those obtained 

 by Murray and Supan.'^ He compared the relation with that of 

 the temperature and precipitation and suggested an intimate 

 physical connection between the latter elements. Moreover, he 

 gave brief but suggestive discussions on the influences of the 

 shielding mountains, altitude of the station, the slope of land, the 

 distance from the sea etc. 



In a previous communication,^^ we have shown a remarkable 

 influence of topographical condition on the distribution of rain 

 accompanying cyclone. The present note which gives a resume 

 of some statistical investigations on the relation of the geographical 

 distribution of the yearly and mean monthly amounts of precipita- 

 tion with the prevailing barometric gradients, may ]^e re'garded as 

 a supplement to the previous note. 



It may be remarked that the subject in question is not without 

 interests also from the seismological point of view, since as already 

 shown by Prof. Omori,^^ there exists a correlation between tlie 

 yearly seismic frequency of some localities and tlie annual amount 

 of precipitation in some other districts. It seems, liowever, still 

 an open question whether the precipitation is the direct agent 

 acting as a secondary cause of earthquakes, or it is rather the 

 barometric gradient which affects the seismic origin and the 

 precipitation at the same time. We will add later a few remark 

 on this latter point, though unfortunately we were not yet able to 

 trace the relation in any conclusive manner, on account of the 

 want of data. 



'2. The data used for the yearly mean barometric pressure 

 and precipitation were taken from Kisyôyôran of the Central 

 Meteorological Observatory, the epoch ranging from 1900 to 1017, 

 while for the monthly means, the materials were taken from the 



1) Hann. Lehrbuch, 2. Aufl. p. 295. 



2) Terada, Yokota and Otuki, Journ. Coll. Soi. 37, Art. 4, (1916) 



3) F. Omori, Bull. I.E.I.C. Vol. II. No. 2. 



