122 TRANSACTIONS iSgg-'oO 



usually large, resulting in the disappearance of half an island 

 or a large mountain, as was the case at Krakotoa in 1883, and in 

 1888 at Banaisan (Japan), the earth shaking is correspondingly 

 greater. It is a significant fact that quakes accompanying these 

 great catastrophes do not usually extend over very large areas ; 

 for example the area shaken at the time of the Bandaisan. ex- 

 plosion was less than 2,000 square miles. If we compare figures 

 like these with those which represent earthquakes some of which 

 originate in non- volcanic districts, and which are repeated many 

 times a year, they are insignificantly small. To produce earth- 

 quakes which are felt over areas of five or ten thousand square 

 miles, and which give rise to waves which may be recorded at any 

 point upon our globe, it is difficult 10 imagine how the primary 

 impulse could have originated at a volcanic focus. Volcanic ex- 

 plosions, as we see them, seem to result from the concentration of 

 subterranean energy at a point; while to shake the whole surface of 

 the globe it would appear necessary that the internal effort should 

 be exerted upon a surface very much larger than we can reason- 

 ably suppose to exist beneath a volcano. 



"A very much more serious objection to the volcanic origin of 

 the majority of earthquakes is the fact that these disturbances 

 are common in the Himalaya, Switzerland and other non-volcanic 

 regions. An analysis of 10,000 earthquake observations in 

 Japan shows that there have been but comparatively few which 

 have had their origin near the volcanoes of the country. The 

 greater number of this series originated beneath the ocean or 

 along the seaboard ; and as they radiated inland they became more 

 and more feeble, until on reaching the backbone of the country, 

 which is drilled by numerous volcanic vents, th^y were almost 

 inperceptible. Beyond the central range of mountains, earthquakes 

 are only rarely experienced ; and what is true for Japan seems to 

 be generally true for the coasts of North and South America." 



Geologists tell us that untold millions of years ago our earth 

 was a globe of molten matter, as ages passed the surface gradually 

 cooled— that a solid crust was formed. They tell us of the birth 

 of mountain ranges and ocean depths, how continents have been 

 lifted out of the oceans, and continents have been buried beneath 

 the waters ; and we learn that the buckling and bending of the 

 crust of the earth as the cooling goes on is even yet in progress ; 



