10 



FAUNA ANTIQUA SIVALENSIS. 



liave been as well laid down as any equal extent of Alpine tract 

 in Europe.' 



All westward from the Sutlej to the Indus is unexplored, 

 and the same may be said of the tract from the Gogra to the 

 Bay of Bengal. 



One or other of us, Captain Cautley or myself, has had 

 opportunities in repeated journeys of examining that portion 

 of the mountains between the Ganges and the Sutlej. These 

 joiu-neys have extended as far as the sources of the Ganges 

 and Jumna, and have intersected the lower tracts of mountain 

 in various directions. As the chain possesses a great deal of 

 uniformity of outline and physical characters generally, for 

 nearly 1,000 miles, it may safely be presumed that the geo- 

 gnostical relations of the mountain masses, as exhibited in 

 the tract we have examined, may be taken as a type of the 

 whole ; excepting the western prolongation along the valley 

 of Cashmeer, where fossiliferous limestones are found. 

 Further we have not had an opportunity of examining the 

 fossiliferous limestones on the northern or Tartary slope. 



As we attribute the formation of the whole line of the 

 Sewalik hills to the alluvial degradation of the Himalayahs, 

 we shall make no apology for entering at some length on their 

 physical outline, river systems, and geological structure. 



The Himalayah mountains are generally described as com- 

 mencing in long. 75°, lat. 35°, where they join on with the 

 Hindoo Koosh, and run down to Bootan, long. 90°, a coui-se 

 of 1,500 miles, skirting the plain of Hindostan. Their line 

 of direction from the Indus is about from WW. to SE. 

 Soiith of the Gogra they get more easterly. 



They form one of the mountain boundaries of an elevated 



' We especially particularise the late 

 Captain Herbert, who, besides an impor- 

 tant share in the Trigonometrical labours 

 of the Survey, inv^tigated with great zeal 

 the Geological and Mineralogical charac- 

 ters of the whole tract, and furnished a 

 voluminous report to the Indian Govern- 

 ment on the subject. Unfortunately, 

 Captain Herbert was a self-taught and 

 book geologist, and he was called upon 

 to describe the geology of an unknown 

 field — a subject new to him, at the very 

 time when he was acquiring his first 

 knowledge of geological science. The 

 consequence is, that his labours have 

 been less valuable than they otherwise 

 would have been from his talents and 

 general scientific acquirements with 

 longer study. He has fallen into several 



important errors. He has described as 

 gneiss an enormous protrusion of granite 

 which forms the axis of the snowy range 

 — shown in a colossal section across 

 many miles, near the sources of the 

 Ganges ; and he has fallen into the same 

 error with regard to a porphyritic trap, 

 which forms a most important member of 

 the Himalayan rocks. He has restricted 

 the rock formations to granite and gneiss, 

 and attached minor importance to an 

 enormous formation of primary sand- 

 stone. We have been favoured lately 

 with a perusal of his manuscript report 

 impublished, and in consequence, in writ- 

 ing on the same subject, we deem it ne- 

 cessary to notice the above, while our 

 numerous references to his report tell 

 how largely we have drawn from it.* 



* Captain Herbert's Report was pub- 

 lished as an appendix to vol. xi. of the 



Joiu-nal of the Asiatic Society. — [Ed.] 



