EARTHQUAKES FROM A JAPANESE POINT OF VIEW. 



By BLACKFORD LAWSON. 

 Member of the Japan Society. 



No other country in the world probably affords such 

 facilities for the study of earthquakes as Japan, nor 

 is there anywhere else such necessity for their 

 scientific investigation. 



Nearly one thousand four hundred of these 

 phenomena are recorded 

 annually in the whole of 

 the Empire, and in Tokyo 

 alone there are, on an 

 average, fifty earthquakes 

 that can be felt during the 

 year, or ahout one a week. 

 Earthquakes, as every 

 one knows, occur in all 

 regions adjacent to active 

 volcanoes, as in the neigh- 

 bourhood of Teneriffe, 

 Vesuvius, Etna, and Strom - 

 boli. which are simply the 

 safety-valves of a single 

 earthquake district. So 

 also Japan, Sumatra, Java, 

 and the islands of the 

 East Indian Archipelago 

 are liable to fearful earth- 

 quakes ; and geologists 

 say that much of Japan 

 would never have existed 

 but for the seismic and 

 volcanic agency which has 

 elevated whole tracts 

 above the ocean by means 

 of repeated eruptions. 



It is, therefore, only to 

 be expected that it occupies 

 an unique position in the 

 world as regards seis- 

 mology. Consequently, 

 there is a special Chair 

 of Seismology and an 

 Institute attached to it in 

 the University of Tokyo, 

 mittee for the investigation of earthquakes, under the 

 direct control of the Minister of Education. Besides 

 this, all the provincial meteorological stations through- 

 out Japan are equipped with instruments for 

 recording and measuring earthquakes, and seismic 

 phenomena are systematically studied. 



In the interior, the writer frequently met, in an 

 out-of-the-wav cave or on the mountain-side, mem hers 

 of the Seismological Society of Japan, originally 

 organised by Professor Milne, who, with their delicate 

 instruments set up, were mapping down every quiver 

 of the earth's crust. 



Figure 152. Earthquake Crack three feet wide, made 



during the great earthquake in the Yamogata prefecture 



(North Japan). 



ind also a special com- 



A study of a map of the world will show that the 

 configuration of earthquake centres, as seen in India, 

 Japan, Java and Sumatra, is that of an arc, and that 

 in each case the earthquake region lies on the outer 

 or convex side of the arc, where the deformation of 



the earth's crust seen in 

 the curvilinear form of the 

 arc shows that the strain 

 is greatest. Thus, in the 

 Himalayas, severe earth- 

 quakes take place on the 

 outer or steep side, rather 

 than on the concave or 

 Tibetan side ; and in the 

 case of the Japan arc, 

 great seismic disturbances 

 occur almost always on 

 the outer or Pacific side, 

 where the Pacific Ocean 

 forms the greatest area 

 of depression in the world, 

 and only small local 

 shocks originate on the 

 inner or Japan Sea side 

 of the arc. 



After the great catas- 

 trophe in North - West 

 India on April 4th, 1905, 

 the Japanese Government, 

 ever eager to study earth- 

 quake phenomena at first 

 hand, sent their leading 

 seismic expert, Dr. F. 

 Omori, Professor of Seis- 

 mology at the Imperial 

 University, Tokyo (see 

 Figure 157) to investigate 

 and report on the nature 

 of the disaster. During 

 several months' stay in 

 Tokyo, the writer was 

 honoured by the friendship of this eminent man, 

 'and spent many delightful hours in his lecture-rooms 

 at the University, and also with his charming family 

 in their picturesque home. From Professor Omori, 

 she learnt that the appalling loss of life in Dharmsala 

 and the Kangra Valley was due to faulty construc- 

 tion, the houses being built of stones roughly piled 

 together without any good cementing material, and 

 surmounted by a heavy roof. 



In construction the first point is to make the 

 foundation solid and as large as possible, because, if 

 weak, cracks will be produced. In two-storyed 

 buildings, the upper store} - suffers more than the 



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