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seen, slates and shales which have until now proved azoic, but covered in by limestone rich in forms of the older Palæozoic period.

I need hardly say that the azoic slates, shales and sandstones which are interbedded with the ashes and amygdaloids in Kashmir are of Silurian date; if we wish, therefore, to colour a map of Kashmir solely in regard to the age of the rocks, we should have to colour all the ashes, slates, &c. Silurian. As the volcanic ejecta much predominate in quantity over the azoic slates and sandstone, I have not coloured the mass solely by age, but rather in view of the nature of the rocks.

But the Himalayan lines of insular volcanoes were not the only ones in that portion of the Silurian sea which we are considering; other linear volcanoes were directed from the N. E. to the S. W. in the longitudes and latitudes where we now find the great Afghan mountains. We know very little of these mountains: we have seen, however, that volcanic rocks of a granitoid appearance form the ranges of hills between Yeusofzaie and Bonneyr, and that clinkstone, granular and porphyritic, is quarried at Jellalabad. Dr. Bellew also tells us that he noticed volcanic rocks amongst the southern spurs of the Sufed Koh.* He also mentions that sharp earthquakes are frequent in the valley of the Korum, and it is reported by the Povindas who trade through the Gulwaira Pass, that a city situated at the back of the Suliman chains has been destroyed by a terrific earthquake. I need not point out the usual relation of severe earthquakes with accumulations of volcanic porphyries, in countries where no active volcanoes have been known to exist for several geological ages past. Then we have seen that the summits of the main chain of mountains, in the Vuzeeri country, are mostly composed of volcanic rocks; but the greatest amount of evidence is

After crossing the hill-pass of Hazrah-Shutur-Gardan, the road lies through a gorge, and a stream or rivulet flows to the westward; in the bed of this rivulet pebbles of porphyry, hornblende and syenite (?) were seen; the surface of the soil was also covered with similar pebbles..... Near the top of the Shinghai Kothul, the volcanic rocks were again seen: Dr. Bellew says: "The surface was strewed with great blocks and fragments of porphyry and syenite, the latter was of various shades, from yellowish-green to greenish-brown, and its fragments shone with a vitreous lustre and broke with a similar fracture." Chapter II. Narrative of a Mission to Kandahar. The above description of syenite does not look much like syenite, it is nearly certain that the rock observed was a hypersthene rock.

derived from the boulders brought down by torrents and from those formerly carried down and now imbedded in the Miocene conglomerates which fringe the base of the Afghan mountains. These boulders and pebbles are mostly greenstone, felstone, trachyte, and porphyry identical with the Himalayan hornblende rock; and that peculiar variety of amygdaloidal greenstone, pierced with gas-vents, which has been described at No. 4 of the section of the Tukt-i-Suliman

in Kashmir, para. 18, occurs in great abundance. (See also Pl. x. figs. 1. 1a.)

There can be, therefore, no possible doubt that the Afghan mountains were at the Silurian epoch an archipelago of volcanic islands and subaqueous volcanoes; indeed, they were merely another group of the same great archipelago; but the fissures or lines on which the vents were situated had a direction N. E., S. W.

Towards the end of the older Palæozoic epoch, the volcanoes appear to have subsided in violence, and allowed the waters of the neighbouring sea to cool. They did not do so, however, until they had ejected so much lava, scoriæ, lapilli, ashes, and debris of the inside of the earth that a great bar, a bar going from the North-west to the South-east and studded with the island-cones of half extinguished volcanoes, had been formed across the sea. A similar bar was produced by the Afghan group of volcanoes, directed N. E., S. W. and the two bars formed a gigantic V, with the angle pointing to the north. On these bars the sea was shallow; neither was it likely to be very deep between the two branches of the V. The end of the great activity of the volcanoes appears to have been marked by the breaking out of a great number of fumaroles or hot springs, depositing an immense quantity of silica, and forming thick beds of quartzite, sometimes pure and clear as glass, sometimes white and opaque as porcelain. We must not forget also, that all analogy points to a general rising of the sea bottom at the north-east of the Himalayan volcanic bar, not as a break, but as a gradual and slow upheaval of the earth's crust under the pressure of viscid granite.

But even these last efforts of the great volcanoes, these bursts of vapours and hot waters, became rare and intermittent, and animals made their appearance in the creeks and bays of the sea between the islands. It was then the dawn of the Carboniferous epoch, and all

over the great bars of volcanic debris a calcareous mud was deposited, teeming with the remains of animals, with the glimmering shells of the Producti, with large flat Orthide, and innumerable Bryozoa and numerous Encrinites which grew luxuriantly on the half chalky, half clayey, fœtid bottom of well protected island seas, gulfs and channels. And so it went on for years and years, until the sea became too shallow for Producti and Orthida to live in, and too easily disturbed to its very bottom to suit the delicate Bryozoa. These animals retired to greater depths on either side of the great bar, and in their stead appeared small Cucullæ, globular Terebratulæ, with here and there, on sandy banks, colonies of large Cardinia or Anthracosia, gibbose and smooth Aviculo-pectens, or radiated ones of great size. In calm waters, flat and large species of Goniatites basked in the sun in company with small Orthoceratida and large species of Bellerophon. Earthquakes were, however, frequent and terrible, raising and depressing large tracts of sea-bottom, folding and undulating the newly formed beds of limestone, so that most of the shells are found broken, and many of them are deformed to a wonderful extent.

Many changes occurred in the sea: clay and sand had been brought down in large quantities from the volcanic islands, and many of the creeks and inland seas were turned into swamps. Long shelving coast-lines extended from island to island, and many groups of the great archipelago were probably united by a low land into larger insular countries. The genera Cuculloa, Cardinia and Aviculo-pecten, and small Brachiopoda disappeared; and in their stead myriads of Gasteropoda, especially the Pyramidellida, living with numerous corals, made their appearance. As the islands joined more and more into larger dry lands, and approached nearer to a long strip of land supporting numerous peaks of extinct volcanoes, the rain-fall increased more and more, sand, mud and gravel accumulated in thicker beds at the mouth of the mountain torrents which now became rivers, and on the swampy shores forests of calamites and other trees grew up, whilst, out at sea, the mollusks and other animals continued to thrive at various depths, according to their kind. What has now become of these forests of calamites? Have they been buried in sands by oscillations of the coast and converted into coal? If they have, has the coal been denuded at a subsequent period? or has some portion of it escaped removal and

does it now lie concealed under newer formations? There is no doubt that great denudation has taken place repeatedly in the Himalaya and subordinate hills; yet basins nicely protected by eruptive or metamorphic rocks, bottoms of valleys or down-thrown beds might have escaped removal. Not a trace of true coal has yet been found in the Himalayas, the Punjab or the Afghan mountains, excepting (geologically speal. ing) the few grains of coal which fill in the cellular tissue of the lepidodendron-like plants described in para. 43, as having been found in one of the layers of the Wean group. This is not very encouraging; but any person who has observed what a thick mantle the Miocene sandstones and the old and new alluvia form over the older formations, would not expect to find coal cropping out in a conspicuous manner. If coal does exist, it will be one day discovered, no doubt; but the discovery will be made by patient and careful study, and not by digging at random with a pickaxe wherever something black is observed. It may be said with truth that the means hitherto employed, by Government or persons interested in the search for coal, have been such that not the smallest reasonable chance of success could be anticipated. But all this is foreign to our subject.

91. The end of the Palæozoic epoch or beginning of the Secondary period was marked by new volcanic action, trifling indeed, if we compare it to the intensity of volcanic power displayed during the Silurian time, but yet highly interesting. I allude to these local outbursts of hot vapours, gases and waters, charged with several minerals, which have taken place in many distant places of the Himalayas and their dependencies. The action is geyserian rather than volcanic, as no true volcanic rocks, that is, no lava, no scoriæ and no ash appear to have been discharged by these vents. The existence of this force is mostly manifested by the metamorphism it has caused in some of the upper beds of the Carboniferous limestone, and by the peculiar way it twisted rocks, then soft, in a manner which appears now incomprehensible, and totally abnormal to the surrounding layers. In some localities, however, it seems that the waters, erupting through the calcareous mud, were so rich in felspars, that this crystallised in

*This remark applies only to the Punjab and the mountainous districts studied in this paper.

minute crystals which now form a sort of intrusive band of a friable incoherent rock.

When this geyserian action subsided, the Palæozoic animals had died out.

92. I now enter upon debatable ground. I have said before, that the salt, gypsum and red marl of the Salt Range-and I need hardly say the gypsum and red marl of Spiti, the gypsum of Rukshu (and that of Rodok ?), and most probably the salt of the Yarkandkash valley, and also that of the Lataband mountains in Badakshan, all belong to the same epoch and have probably a common origin. I have said before that, this Saliferian formation has been placed by Dr. A. Fleming in the Devonian. Dr. Jameson makes it superior to the Carboniferous; Major Vicary and M. Marcadieu believed it to be Miocene or Pliocene; some will have it volcanic, others sedimentary; but nobody gives a good and well defined section of the relations. of this formation to the rocks above and below it.* This is much to be regretted, and I will not increase the confusion by discussing here the reasons which make me believe that the salt and gypsum of the Himalayas belong to the Trias or the Permian. My opportunities of observing the Saliferian formation have been few and of short duration, and I have no good section to give in support of my opinion. I shall therefore refer the reader to the note to para. 64, and proceed with the next formation.

93. Whatever had taken place beeween the end of the Carboniferous epoch and the beginning of the Jurassic, it appears tolerably evident that the Jurassic sea bathed the shores of a long strip of land or succession of large islands, very similar to those which the Carboniferous sea had bounded. The Jurassic sea does not appear to have been much deeper than the Carboniferous one had been; the same impurity of the limestone is noticed, the same admixture of sand and clay with the calcareous matter, the same rarity of clean drifted sands, the same prevalence of thin-bedding, false-bedding and continual

* Dr. A. Fleming gives some sections in his Report on the structure of the Salt Range; but only two of these show the relations of the salt marl to the Carboniferous limestone, and in one, sect. No. VIII., a number of more or less theoretical faults are introduced which, if placed at the base of the mountain limestone escapements, would then make this rock inferior to the salt. Another section, No. VII, shows an anticlinal across a ravine, and then the salt marl appears indeed to be placed under the Carboniferous limestone.

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