64 H. I. JENSEN. 



In the island of Sikok, the north-west portion consisting 

 of ancient crystalline schists, falls in the A region (winter 

 earthquakes), whereas the south-east portion consisting of 

 mesozoic sedimentary rocks, falls in the B region. But 

 probably most of the earth quakes here (summer earthquakes) 

 are connected with submarine elevation and folding along 

 the volcanic line east of the island. 



In the island of Kiu-Siu volcanic rocks and Tertiary 

 sedimentary beds are plentiful, yet it belongs to Dr. Omori's 

 A region. Perhaps elevation by rise of isogeotherms and 

 volcanic action lias ended here, and contraction processes 

 may have set in. 



It would be of great interest and importance to this 

 branch of science if our Japanese confreres would ascertain 

 exactly what relations obtain between earthquakes and 

 eruptions in each of these regions and (1) solar conditions, 

 (2) lunar phases and declination, (3) atmospheric conditions, 

 cyclones and anticyclones, cold winters, hot summers, etc. 



Some of this work they have already commenced, perhaps 

 all; indeed Japanese scientists, hampered by want of funds 

 and semi-isolation from the rest of the scientific world, 

 have done wonders ; again and again they have shown 

 their ability in geology, metallurgy, the study of alloys, 

 meteorology and physics, and we should not wonder if the 

 whole of this work has been almost completed by them. 



VII. Summary. — From my researches it appears that 

 (1) a marked connection exists between sunspot minima 

 and seismic disturbances. Sunspot maxima have a much 

 less well defined influence. 



(2) Perigee is a powerful secondary cause of earthquakes. 



(3) The equinox has likewise a marked influence. 



(4) New and full moon and the crossing of the equator 

 by the moon are only capable of inhibiting earthquakes 



