26 



may be said to be common to and characteristic of all parts of 

 India it is the Banyan, or Ficus Bengalensis, which is seen both 

 in moist and deciduous forests, and in the most arid parts. 



In regard to the physical changes in the conformation of the 

 land due to the effects of Ilainfall, it is necessary to understand 

 the river system of the country. Beginning with the N.E. we 

 have the Indus with a drainage area of 311,661 square miles, its 

 actual source being in Thibet at an elevation of 16000 ft. above 

 the sea. 



The geological formation through which • the Indus proper 

 flows is chiefly Metamorphic, while its tributaries the Jhelam, 

 Ravi, Chenab, and Satlaj run through alluvium and lower tertiary. 



Below the Indus we find the Indian desert of Rajputana 

 with little or no rain and no river of size or importance, and 

 immediately below, the basin of the Narbada and Tapti, stretching 

 more than half way across India, driven in like a wedge between 

 the basins of the Ganges on the north and the Godavery on the 

 south. The united area of the three rivers of the Narbada basin 

 is 85,800 miles. It will be observed that below this basin there 

 are no more rivers flowing westward, and this is due to the fact 

 that the Western Ghauts run down the western edge of the 

 peninsula from a little above Bombay to Cape Comorin. Returning 

 therefore to the north part of India we find the great basin of the 

 Ganges, a river 1514 miles in length, with a drainage area of 

 391,000 square miles. The geological features of this basin are 

 chiefly Cretaceous trap Silurian and upper tertiary. 



On the extreme east of India lies the basin of the Brahmaputra 

 361,200 square miles in area. This river in its course of 

 1800 miles is so heavily freighted with silt, that the least 

 impediment in its course causes a deposition, and a steamer 

 anchored overnight in sufficient water, sometimes finds itself on an 

 island of silt. Some of these silt islands are of great size, and 

 one has been ascertained to be 441 square miles in area. 



To the silt brought down by the Brahmaputra and Ganges is 

 due much of the formation deltaic and otherwise of the land at 

 the head of the Bay of Bengal. 



Below the basin of the Ganges with its watershed in the 

 high land of Central India the Mahanadi and smaller rivers form 

 the next basin, below which and stretching almost across the 

 peninsula is the basin of the Godavery,, 898 miles in length, with 

 a drainage area of 112,200 square miles. The deltaic formation 

 of the mouth of this river is one of the features of the eastern 

 coast, and the river is so highly charged with silt in the rainy 

 season that the sea 8 or 10 miles out is of the colour of a muddy 

 river, and not infrequently coasting steamers come across huge 

 trees which have been carried down the river during floods. 



