Valley of Oodipom-. 281 



rowtee. These have a tubular form, and exhibit mural preci- 

 pices, and abrupt escarpments, which dis})lay the horizontally 

 stratified rocks of which they are composed. The aspect of the 

 country is singular, and, as viewed from the heights, I could 

 compare it to nothing else than a huge plain studded with enor- 

 mous cubic crystals, of a perfectly regular and determinate 

 form. 



In the northern portion of the district, the sandstones are seen 

 reposing in an unconformable, overlying, and insulated posi- 

 tion, upon the tops of hills formed of the nearly vertical strata 

 of the older rocks, which now begin to make their appearance. 

 The hill upon which the fort of Mandulghur stands is an exam- 

 ple in point*. In such cases, the unconformable rocks must 

 have been deposited upon strata which had already assumed a 

 vertical position. 



While we refer the epoch of elevation of the hills and hill- 

 ranges of this portion of India to a period posterior to that 

 which gave birth to the formation to which the horizontally stra- 

 tified limestones and sandstones belong, we may, at the same 

 time, suppose that, prior to this date, the older rocks had, in 

 some localities, been subjected to paroxysmal elevations, which 

 bad imparted to the strata a vertical position, and that, in after 

 times, they were still farther elevated en masse, heaving up- 

 wards on their summits tubular portions of the formations which 

 had been deposited upon them. 



The tubular hills, composed of horizontally stratified rocks, 

 would seem to have owed their origin to a similar upheaving 

 agency exerted in a vertical direction, and perhaps the tendency 

 of such rocks to be ruptured along fracture-lines, at right-angles, 

 or nearly so, to each other, and the disposition of their fragments 



• Immediately to the northward of this position, we have a succession of 

 rocks of the argillaceous and micaceous schist series, which are succeeded, in 

 the same direction, by the granitic rocks of Ajmeer. The phenomena alluded 

 to in the paper may all perhaps be explained, on the supposition that the 

 energy of the agent which upheaved the granites was in the inverse ratio of 

 the distance from the centre of elevation. In Harowtee, this agent, opera- 

 ting upon the inferior rocks, may have caused internal commotions and up- 

 heavings sufficient to modify the position, and, in some cases, to effect the 

 rupture and dislodgment of the superjacent sandstones, without being able to 

 accomplish the elevation of the older rocks through these sandstones. 



