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clay, sand and boulders could not fail to convert the sea, which we have seen was shallow, into dry land, and thus we have this overlapping of the Upper Micoene on the edge of the Lower which is represented at para. 11. The Lower Miocene was itself exposed to the denudating influence of the rain, and boulders of Lower Miocene sandstone are common in the Upper Miocene.

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The Upper Miocene appears to have been altogether a fresh-water formation; I mean, an accumulation of materials brought down by rivers of large size, which, in all probability, wandered through the flat plains of the lower Miocene, and extended in deltas and marshes and creeks, just as the Ganges and the Indus are observed to do now-adays. We may fairly imagine these Miocene tracts to have resembled closely a modern Indian plain traversed by large inundating rivers— a thick jungle of high grass and small trees for the elephant, the mastodon, the monkey. and a host of other animals to dwell in, and on the sides of the large meandering rivers, wastes of sand and clay, shallow pools and quicksands for the delight of the crocodiles, the tortoises and the hippopotamus. On sands left dry by changes in the course of the rivers, or piled up in undulating hillocks by the winds, grew thinly planted trees, such as we now see in the sandy tracts of Scinde, to feed and shelter the camel, the giraffe, and innumerable deer of various species; and on intermediate lands, good pasture supported the horse, the ox and sivatherium.

In the districts of Rawul Pindee, of Jheelum, of Bunnoo, of Kohat, the Upper Miocene has a thickness of more than 2,000 feet; but in the Rajaori and Poonch provinces of the Maharajah of Jummoo's kingdom, the bed attains a much greater thickness.

Any one who travels through the plains of the Punjab will notice the great quantity of cows, of oxen and horses seen loose on the sand near every village, and will remark at the same time, that when a stream has cut through the sand and thus exposed a section, not a bone is seen buried under the surface. If, however, he comes to a marsh, such as the one near Guriwall, in Bunnoo, he will observe that the bones will remain perfectly preserved in the thick mud, saturated with kullur,* which forms the bottom of the

* Impure Sulphate of soda, with a little carbonate of soda and chloride of sodium, which impregnates, more or less, nearly the whole of the soil of the Pun. jab, and effloresces on the surface after rain or irrigation.

marsh. Now this kullur appears to have existed in the soil of the Upper Miocene, as the sandstones of that age are often covered with an efflorescence of that salt; and, indeed, that now seen in the alluvium is derived from the disintegrating, decaying and washing away of the Miocene beds. The fossil bones are always found either in a dark clay-stone, which has a bitter taste when applied to the tongue, or in a light-coloured sandy claystone. It is therefore highly probable that the existence of a marsh or swamp is necessary to the preservation of bones and their fossilification. This accounts for the bones being found in beds of limited extent, whilst for many miles not one is to be discovered; but it also brings additional evidence that the Upper Miocene was deposited as a growing delta, similar to the Sunderbunds of the Ganges and to the creeks of the mouths of the Indus.

What a singular landscape this belt of land must have presented! If we remember that at least seven different species of elephants roamed in these jungles, some much larger than the living one, and with tusks nine feet and a half long; that the dinotherium had a skull three feet and nine inches in length; that the mastodon was 17 feet long from the tail to the end of the tusks; that the sivatherium was a gigantic four-horned antelope-like animal; that the crocodiles were much larger than they are at present, and that the tortoises had a shell measuring 20 feet across; we may wonder indeed at the strange appearance which the jungles must have presented!!

I have called this fossiliferous formation Upper Miocene. In placing it in the Miocene, I have adopted the general opinion of geologists, but it may be Pliocenic and not Miocenic. I have not succeeded yet in discovering shells in these beds, and without shells it is impossible to fix with certainty the age of the formation.

I have forgotten to notice, that during the whole of the Miocene epoch there was a slow and steady sinking of the land. This sinking allowed of the accumulation of materials to the great thickness I have indicated, but unlike that which took place during the Eocene period, it was not sufficient to keep the country under the sea, the quantity of sand and clay and boulders, deposited by the rivers, being more than adequate to compensate for the sinking. The country, however, by the sinking was kept to a very little height above the sea level, and

the inundations of great rivers added continually to the thickness of the deposit.

97. There is no evidence of any violent action having taken place during the Eocene and Miocene epochs. There had been risings and sinkings of the whole country, but these were imperceptible to the senses, and were probably not more active than the same phenomena which now occur in many parts of the world, unknown to the inhabitants. The belt of flat land had increased to a good breadth, and the coast had become sufficiently distant from the mountains to enable the animals to live in peace and plenty, away from the storms and torrents of the hills, when the whole of the portion of the earth we have been considering was raised into an immense vault, by the forcing up of granite assisted by gases. When the gases condensed or escaped, the arch settled down by fracturing its sides, and these faulted sides of the arch are now, what we call the Himalayas and the Afghan chains of mountains.

When the settle-down began to take place, and the sides of the arch or vault were being broken, the direction of the linear volcanoes of the Silurian epoch compelled the new fractures to conform to it. On the eastern slope of the vault, the fractures ran from N. W. to S. E., on the western slope from N. E. to S. W. As is generally the case in an anticlinal, the highest portion of the vault settled down again to a level much lower than the sides, and we have therefore, in the northern Punjab, low hills, whilst on each side we have mountains towering to the sky.

It is not necessary to enter here into all the details of the complications which the masses of porphyry, trachyte, granite and other rocks, which had been cooling ever since the middle of the Paleozoic epoch, caused in the upheaval of the Afghan-Himalayan vault and in its settle-down. These details have already been sufficiently indicated in paras. 81 to 87. But I will insist on the effect of these masses being forced up like wedges through the rocks which covered them, and by their filling up a great deal of the space once occupied by these covering rocks, they compelled these last to be either folded or broken into pieces and packed edgeways.

It is not necessary to imagine that the top of the vault was raised to the same height as we now see the great peaks of the Himalayas

In the settle-down, the parallel zones, into which the sides of the vault were broken, would naturally assume an angle of dip much greater than was that of the vault previous to its fracture, as the sides of the vault, in coming down again, would be submitted to considerable pressure, and therefore much redressed. It is not unlikely, therefore, that it is the effect of this pressure which has caused, in many mountains of the Himalayas, the appearance of younger rocks dipping under older, of felstone under porphyry, of schist and gneiss under granite.

The geologist must naturally expect to find a great many complications amongst these immense mountains. The view I have endeavoured to explain is a general one, and will, I hope, be better substantiated when we know more of the countries of the AfghanHimalayan system. With a little thought, I entertain a hope that the geologist, in finding apparent contradictions to what I have advanced, will always be enabled to discover the cause of the complication, at first apparently irreconcileable to my hypothesis.

There is one more remark to be made. The direction of the Silurian linear volcanoes of the Himalaya not being parallel to that of the Afghan chains, we have not a true anticlinal, but an oblique one. At the northern end of the axis of this oblique anticlinal, we have therefore a pressing of the sides one against the other, whilst at the southern end, we have a wide divergence of the ridges at the northern end of the axis, we have the chains abutting one against the other, and thus supported at a great height; at the southern end we have the central beds unsupported and sunk down very low when the settledown took place; hence the high plateau of Pamer at one end and the low plains of India at the other. Again, when the Himalayan slope of the anticlinal was settling down, many of the great masses of porphyry, schist and gneiss resisted the general tendency to dip N. E., and caused a local fault to take place. This fault acted as the axis of an anticlinal for the locality immediately surrounding the mass of porphyry, schist or gneiss; and we find therefore such huge masses assuming the dip of the western branch of the Afghan-Himalayan anticlinal, or dipping N. W. Hence, the singular phenomenon, long ago noticed by Captain R. Strachey, that some of the great peaks of the Himalayas dip N. W., whilst all the beds round them dip N. E. It is also this same obliquity of the anticlinal which has

caused these numerous transverse faults observed in the Himalaya, which have a general direction from N. to S., and with the beds crushed one against the other at the northern end, whilst the fault gapes at the southern extremity.

All these phenomena, and several others which strike the naturalist as he travels through these mountains, appear to me to prove without a doubt, that the upheaving force was not applied at one certain point or along one certain axis, but that the whole country, now covered by the Afghan and the Himalayan mountains, was forced up into an immense dome or arch, which broke along certain lines determined by pre-existing volcanic zones, and settled into an oblique anticlinal, of which the slopes are sliced by a succession of parallel faults.*

98. It is a question of considerable interest to determine, with some precision, the epoch at which the great and last upheaval of the Himalaya occurred. We know that it was after the great mammals had become developed; and the extraordinary number of mammalian species found in the Sewalik hills would naturally induce one to consider a portion at least of what I have called the Upper Miocene as older Pliocene. The Aralo-Caspian formation or steppe limestone, a brackish water deposit, has been placed by Murchison and DeVerneuil in the older Pliocene; and one cannot help thinking that these shallow but immense inland or inter-insular seas must have existed previous to the final upheaval of the great mountains of Central Asia, and that it is indeed movements connected with this final upheaval, which have dried up the steppe-limestone and reduced these great seas to their present dimensions.

On the other hand, we have seen, that there exist in Thibet and in Ladak great beds of horizontal deposits, unconformable to the beds on which they abut, and containing fossil bones. Captain R. Strachey appears inclined to believe these beds to have been deposited previous to the upheaval of the Himalaya; but I think the hypothesis is not tenable, as it is impossible to understand how a "true sea-bottom

The hypothesis (advanced, I believe, by Professor Ansted in his "Ancient World'') that the rising of Central Asia caused a depression in the Indian Ocean, marked by the coral islands of the Lacadives, the Maldives, the great Chagos bank and some others, is ingenious; the depression, however, requires proving by actual observations.

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