1913-] SEE— ORIGIN OF HIMALAYA MOUNTAINS. 513 



volcanic violence. This volcanic chain is analogous to that of the 

 Aleutian Islands, except that the middle part is su'bmerged, and the 

 two ends raised above the waves. 



The line of thought here developed enables us to understand the 

 volcanic activities of Farther India, and also the terrible belt of earth- 

 quakes in Assam and the adjacent regions south of the Himalayas. 

 Part of the ancient sea valley is above the water as low land, and 

 part still in the ocean, and covered by the sea to a considerable 

 depth. 



West of India, we have the complicated mountain ranges and 

 earthquake belts of Afghanistan and Persia. It would be difficult 

 if not impossible to understand the phenomena they present if 

 studied alone; but if studied in connection with the developments of 

 India and Farther India above discussed, it is easy to see that 

 Afghanistan and Persia were built up in like manner, and at no very 

 distant epoch were beneath the sea. 



In his article on the " Himalayas," Encyclopedia Britannica, 

 9th edition, the late General Strachey has strongly emphasized the 

 view that the mountains and table lands of Afghanistan and Persia 

 are intelligible only in connection with those of India. 



" It is after the middle Tertiary epoch that the principal elevation of 

 these mountains took place, and about the same time also took place the 

 movements which raised the tablelands of Afghanistan and Persia, and gave 

 southern Asia its existing outlines." 



Fle also points out the fact that at no very distant geological 

 epoch the ocean extended from the Arabian Sea through the 

 Persian Gulf to the Caspian and Mediterranean. The continuation 

 of the earthquake belt through this region of Western Asia is 

 therefore quite intelligible, and the existence of active volcanoes 

 near the Caspian a survival of present and former relations to the 

 ocean. 



The annual rainfall south of the Himalayas amounts to about 36 

 feet, and this is so enormous as to be almost as effective as a shallow 

 sea in keeping alive earthquake processes. 



It is established by observation, for example, that the very 



