338 Economic Geology of Assam, [No. 4. 



These clays are first seen on the South bank of the Brahmaputra 

 immediately after leaving Dekhoo Mookh. The bluish tough clay 

 is first visible, and at the mouth of the Jansee crosses the Brahma- 

 putra to Saulmarah, where an extensive native pottery work is 

 established, supplying Upper Assam above the Dekhoo. A fine 

 under-stratum of various coloured clays continues visible until past 

 Kokilah Mookh, when the bend in the stream, and the sand deposit 

 opposite Moghur, shuts them out ; but I think the same clays will 

 be found along the whole line of the extreme South bank running 

 down into the great clay deposits of the Golaghat district and 

 Dhunseree, where the section made by the river developes the same 

 variety of clays, extending from what is called Mourah Mookh to 

 Bur Pathur, and probably to Dhennapore. This clay deposit must 

 be of great age and depth — some of the clays forwarded having 

 been found under-lying a bank of gravel and sand 60 to 70 feet 

 high. In many parts of the Dhunseree river, the clays have become 

 mixed with a highly ferruginous marl, attaining to a state of sand- 

 stone. Laterites are also abundant in the bed of the Dhunseree, 

 which shews these to be formed in the clays. An oxide of iron, 

 consisting of small grains mixed with very hard laterites is washed 

 from the whitish coloured clays at several points on the line of the 

 river as well as inland. Proceeding upwards on the Dhunseree 

 river, the land becomes higher above the Doyong river, and in the 

 vicinity of the Namber, the clays are more indurated and of a slaty 

 clay nature. 



In the Namber the sulphureous hot springs are situated a few 

 yards distant from the junction of that stream with the Dhunseree. 

 At the springs nothing is seen but Felspar gravel. In the Dhun- 

 seree the next turn above the Namber, are several hot springs, con- 

 taining salt. The bed of the river exhibits masses of Felspar rubble 

 cemented together forming a hard rock, and large masses of fossil 

 wood appear to be imbedded in this as well as lying in the stream. 

 From the Namber to Bur Pathur, for a distance of nine miles the 

 country is undulating with low hills, the soil bearing a profusion of 

 timber trees, the nohar and toon the most conspicuous, and many 

 rare and beautiful plants. Throughout this tract, which seems an 

 offshoot from the Eengma Naga hills, there are many deep dells, 



