



i 



1916.] The Third Indian Science Congress. lxxxix 



Delhi ridge ; Mr. Middlemiss has found signs of a transverse 

 strike in the Himalaya on a continuation of the Arravalli 

 alignment. 



Similarity also exists between the rocks in Cutch and 

 those on the other side of the Indus in the hills of Sind. 



From the Bay of Bengal to the Mediterranean. 



Geologists have discovered that the ancient table-land of 

 the Vindhyas and Deccan is a remnant of a much greater 

 table-land that in very early ages included Africa and Arabia. 

 Africa and Arabia and the Deccan table- land are in fact frag- 

 ments of one extensive and ancient continent. Hitherto I 

 have been considering the peculiar trough that skirts the 

 northern edge of the Indian table-land. Let us now consider 

 whether this trough is continued to the east or to the west. 



On the east we find one of the great linear deeps off the 

 coast of Java and Sumatra. It is 24,000 feet deep. In 1883 

 the Krakatoa eruption took place in the Sunda Straits. Great 

 depths have also been discovered off the Nicobar Islands and 

 earthquakes have occurred on the Chittagong coast. In con- 

 tinuation of the Gangetic trough we thus find in the Bay of 

 Bengal a line of seismic activity, and of submarine deeps. 



To the west of Karachi we see the Persian Gulf, and the 

 plains of the Tigris-Euphrates. The plains of the Tigris- 

 Euphrates are very similar to those of the Ganges : they consist 

 of mud, sand and sediment lying in a long trough between the 

 ancient table-land of Arabia and the mountains of Persia. 



Further west we find the Euphrates trough is continued 

 by the Mediterranean Sea, and the Mediterranean is bounded 

 on the north by the Taurus mountains, by the Balkans, 

 Carpathians, Appenines and Alps. 



Throughout the whole distance from Calcutta to Sicily we 

 see that the old table-land India-Arabia-Africa is bounded on 

 the north by a long trough, and that this trough is in its turn 

 bounded by the younger mountain ranges from the Himalaya 

 to the Alps. Geologists have discovered that all these moun- 

 tain ranges were elevated in the same era ; they are all of the 

 same age. 



I submit for your consideration that the Ganges-Indus- 

 Euphrates-Mediterranean trough is an indication at the Earth's 

 surface of a rift in the sub-crust. 



When we get as far west as Sicily, we reach a region of 

 active volcanoes, Etna and Stromboli. Italian Geologists be- 

 lieve that Sicily has been separated from Africa by recent 



subsidences. 



The Earthquake Record. 



The 



earthquakes throughout the historic period. And the recent 



