GEOGNOSY OF THE HIMMALEHS. 237 



fine granular galena, is found in clay-slate and clay-slate 



limestone. „ . ,, j- ■ • 



t 5 Secondary Rocks.— Resting upon the preceding primi- 

 tive and transition rocks, but occupying a much lower situa- 

 tion, we find formations of the secondary class. These 

 form the immediate north-east boundary of the^ great allu- 

 vial plain of Middle India, and are principally of sandstone, 

 in all probability of different ages. ^,,,^.11 1 



Mr Scott has communicated, through Mr. Colebrooke, 

 «ome details in regard to the secondary strata' he observed 

 on the banks of the Tista and Subuck, where they issue 

 from the mountains of Bootan. The strata he noticed on 

 the Tista are micaceous sandstone, bituminous shale, slate- 

 clay, and coal ; and rocks of the same descnption were 

 observed on the Subuck. The coal has a dark hrown colour, 

 with a conchoidal fracture, and is associated with tossil 

 wood. The colour of the coal would seem to intimate that 

 it belongs to the brown coal series, and therefore is of a 

 more recent oriffin than the coal of Damoda near to Cal- 

 cutta. The hills foraied of these strata, in Mr. Colebrooke s 

 opinion, may be considered as fair examples of the entire 

 range which skirts the north of Hindostan. They rise to no 

 sreat height, and constitute the first step from the plain ot 

 India a'scending towards the mountains of Bootan and the 

 loftier peaks of the Himmalehs. Everywhere, so far as is 

 vet ascertained, the lower range of hills consists of sandstone 

 abounding in mica. To the above details we may add, that 

 throughout the whole line of sandstone hills that 1^ at the 

 foot of the Himmaleh chain, according to Captain Herbert, 

 coal occurs in beds varying from a quarter ot an inch to a 

 foot in thickness. It often shows the ligneous texture ; 

 and where that texture is no longer visible it presents a 

 conchoidal fracture, and burns with much flame and smoke. 

 It appears to be the brown coal of Werner. 



6 Tertiary Rocks.— An interesting display of rocks ot 

 this" class was discovered by Mr. Scott at Cooch-Behar on 

 the north-east border of Bengal, where the Brahmapoutra 

 emerges into the plain. The strata are of yellow and green 

 .<;and, alternating with clay, that lie horizontally at the 

 height of about 150 feet above the level of the sea, and 

 contain organic remains resembling those of the blue clay 

 of the London and Hampshire basins. Mr. Scott also 



