GEOGNOSY OF FEXIXSULAR INDIA. 245 



In our progress onward we pass the coal-field of Da- 

 moda, already described ; and from it, in a north-westerly 

 direction, the road to Benares leads over granite, of which 

 the ranges of hills on the left, and the whole country as faor 

 as the Soane, and round by Shirghati and Gaya, is probably 

 composed. On approaching the Soane river, and crossing 

 the hills behind Sasseram, sandstone begins to appear, and 

 seems to continue, with probably only one considerable in- 

 terval, all the way to Agra, forming, as already mentioned, 

 the southern boundary of the Ganges and Jumna ; that in- 

 terval occurs in the low lands of Bundelcund, where the 

 remarkable isolated hills, forming ridges running south- 

 west and north-east, are all granite and syenite, the high 

 lands being covered with sandstone. The geognosy of the 

 Tyndhia mountains, which cross the peninsula trom east to 

 west, uniting in some degree the two northern extremities 

 of the Malabar and Coromandel ranges, has been partially 

 examined. It can be traced ranging about 75° west, from 

 the point called the Ramghur hills, towards Guzerat. The 

 predominating rocks in this vast space are granite and 

 syenite, with gneiss, mica-slate, quartz-rock, clay-slate, 

 graywacke, and other primitive and transition stratified 

 rocks, the relations of which may be well studied in the 

 Oodipoor primitive chain of this range, also on the verge of 

 the trap near Jabulpur, and in the bed of the IS'erbudda at 

 Beragerh, near Garrah. These rocks are more or less ex- 

 tensively covered by secondary sandstones and limestones, 

 of the coal, new red sandstone, and lias formations, and 

 traversed and overlaid by enormous bodies of trap. The 

 extent of the trap-rocks is verj' great ; for it has been traced 

 northward all over Malwah and Sagar, and eastward to- 

 wards Sohaghur and Amerakantak; thence extending 

 southward bv Xagpore, it sweeps the western confines of 

 Hydrabad, nearly to the fifteenth degree of latitude, and 

 bending to the north-west, reaches the sea near Fort Vic- 

 toria (including the islands of Bombaj^ Salsette, and Ele- 

 phanta), and forms the shores of Concan northward, all the 

 way to the mouth of the Nerbudda, covering an area of up- 

 wards of 200,000 square miles. This vast igneous forma- 

 tion covers sandstone in the district of Sagar, and comes 

 also in contact with limestone, which it converts into dolo- 

 mite. This sandstone, which is red, and generally hori- 

 X3 



