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is first roasted, and becomes black and highly magnetic. It is then worked either with nummulitic limestone or pieces of the coral-reefs and smelted with charcoal in small furnaces identical to those seen in Kashmir. I found at Mackeen a house with two of these furnaces and heaps of charcoal, of iron-ore and of limestone, evidently collected for smelting, and I could thus identify the ore used by the Wuzeerees, though no information was to be obtained from the people. I have had, since, pieces of ore brought to me, at Bunnoo, by the Wuzeerees engaged in trade and who bring the pig-iron to the plains for sale, and it is exactly the same ore which I had seen at Mackeen, and which I had observed in situ as one of the members of the nummulitic formation. This shale is heavy, generally covered with a rusty powder; it varies in colour from reddish-brown to nearly black; it soils the hand, it is not calcareous, and the richest parts of it have a tendency to form concretions, or at least to assume a sort of concentric slaty cleavage. It is only smelted to a paste, not to a fluid, and is refined by hammering. The iron produced is soft and fine-grained, but apt to exfoliate, a defect which is evidently the result of the metal being half worn-out by the extensive hammering to which it is submitted.
The carboniferous limestone was found in situ in Wuziristan. But that such rocks do exist in the hills between the British border and round the central chain of the Afghan mountains, is proved by the boulders in the rivers which drain those countries. Major Vicarey found boulders of limestone containing carboniferous fossils in the streams near Peshawur; Dr. Fleming found " Productus-Mmestone" in the ravines which drain the Solimanee chain towards the east; and I have found in the bed of the Korum, a torrent which drains the southern slopes of the Sufed Koh, boulders of a black limestone containing ProducinB cora and P. Humboldtii.
64. In the Salt Range the carboniferous limestone is well developed and attains, according to Dr. A. Fleming, a thickness of 1,800 feet. It begins near Noorpoor in Long. E. 72° 30', as a thin bed, which increases as it goes towards the west, and attains its maximum of development near Vurcha, in Long. 72°. It decreases again towards the Indus, and is not seen at all near Maree and Kalabag; but on the right bank of the river it reappears about six miles west of Kalabag, and is continued in the Chichalee range and the northern end of the Speen or Lowa Gar. It appears to be identical, in fossils and in lithological characters, to the limestone of Kashmir. Dr. A. Fleming does not mention its ever resting on quartzite or volcanic ash, but supposes on the contrary that it rests on the Saliferian formation, which he, in consequence of this view, calls Devonian. Whatever little of the carboniferous limestone of the Salt Range I have myself seen, is too much disturbed to allow me to form an opinion; I certainly never saw any quartzite underlying the limestone in the Salt Range; but such quartzite exists in the Rottah Roh, and it is evident" that the Rottah Roh carboniferous limestone, and that of the Salt Range are one and the same sheet of deposit, broken and separated by convulsions of a posterior age. This, however, does not prove much either way.
The long controversy about the age of the salt and gypsum in the Alps bids fair to be repeated in the Punjab. The Saliferian of the Salt Range has already been placed by successive observers in nearly every formation from the Devonian to the Miocene 1 In the Alps, geologists appear to have once become desperate at the fight, and M. Sismonda published in the Comptes rendits de V Academie des Sciences de Paris (Vol. III. p. the somewhat startling hypothesis that
"in the Alps the shells of the Lias lived at the same time as the carboniferous plants"!!!... It is not a little curious resemblance that in the Maurieune, in Savoy, (the great field of contention,) the gypsum, quartzite, marl, &c., are much disturbed by local foldings and bendings, and appear to be placed under the carboniferous rocks (terrain houiller). Fortunately a thin, but very persistent and well-characterised bed, the Infra-lias, has enabled the geologists who have best studied this locality, to fix the position of the red marl, red and green shale, quartzite, gypsum, &c, in the Trias, and to show that the apparently inferior position of these Triassic layers was due to such great disturbances and reversions of strata as one may reasonably expect to have accompanied the surging up of mountains like the Alps. Less fortunate or less industrious than they of Europe, we have not yet found the Infra-lias in India, and we have not therefore got hold of the thread which led so successfully the Swiss and French geologists to a true understanding of the Alpine Saliferian.
I wish that I could have determined satisfactorily the age of the
s»lt of the Punjab, before forwarding this paper to the Society; bnt I see at present but little chance of my being able to visit again and study the Salt Range within a reasonable time. My own impression, from what I have seen, is that the Saliferiau of tho Punjab is Triassic or Permian.
This Saliferian formation, (whatever its age may be,) plays a very important part in the economy of Upper India, and may possibly be made a great deal more of than at present. It gives a supply of salt •which pays to the State a handsome revenue; it has been the original source of the Reh or Kullur of the soil, an impure and effervescing mixture of saltpetre, of soda and chloride of sodium, which renders fields barren and thus causes very serious losses to that same revenue. There can be little doubt that it contains some at least of the numerous minerals discovered in the Russian salt mines of Stassfust-Auhalt, and it is very possible that it will one day give some fertilizing material which will more than repay the loss caused by the Reh. It is a fine field for research, and only wants work bestowed upon it to yield valuable results.
Any one "who has visited the Saliferian of the Punjab must have been struck by the much disturbed state of the beds. These appear as if they had been raised into a succession of small cones or "bonrsoufflures," and suggests at first sight the idea of the Saliferian having been at some time or another violently dislocated by eruptive gases and sublimated minerals. This is so marked in some localities that Dr. A. Fleming advances, as a possible hypothesis, that the salt may be of volcanic origin. Rut the stratification is generally so well denned (the courses of salt being separated by thin layers of red marl or of cellular gypsum) that we cannot regard the salt as intrusive; it is decidedly sedimentary. That the disposition of the salt gypsum, bipyramidal quartz crystals, &c, &c, took place under the influence of heat, due probably to hot springs, is pretty certain. For Charpeutin and de Beaumont have shewn that the gypsum was first deposited as anhydrite, and this anhydrite must of necessity have been prccipited from hot solutions; neither do we see how sea water could deposit gypsum, unless submitted to a high temperature; whilst, high temperatnre being admitted, the precipitation of gypsum becomes easily explained, if we remember Mr. David Forbes's observation in Peru: "The quantity of sulphates and more especially of sulphate of lime, "included invariably in these deposits, might, at first sight, appear to the observer too great to suppose it due only to the evaporation of "the sea-water; but I believe that this impression will be dissipated "when he sees the enormous amount of gypsum removed in the form "of hard white cakes or sedimentary crust, from the boilers of the "large distilling machines in use along this arid coast, for producing "from the water of the sea a supply of fresh water for the maintenance "of the inhabitants, beasts of burden, and even the locomotive engines "of the railways along the coast. It appears not necessary to suppose, "as has been put forth, that the sulphates present have been formed "by volcanic exhalations acting upon the bed of salt."* What induces us readily to admit of the existence of very numerous and extensive hot springs during the Triassic epoch in the Punjab is, that even now-a-days the Saliferian formation is remarkable for the great number of hot Bprings it contains; indeed hardly a hot spring in the Punjab and the Himalaya is to be found unconnected with the Saliferian, and whenever we find Saliferian beds, we generally also find hot springs. This is true of the Salt Range, of the Rottah Roh, of Kangra,t of Rukshu in Thibet, &c. We may therefore conclude from these remarks that the salt, gypsum, &c., is sedimentary, though deposited under peculiar circumstances, viz., the presence and influence of hot springs. How then to account for the very disturbed state of the Saliferian beds, for these limited, local, fragmentary disturbances which give to the beds so elastic an appearance? Two ordinary causes appear to me sufficient to account for this: one is the transformation of the anhydrite into gypsum by absorption of water, a phenomenon which continues to take place now-a-days. This absorption of water and the consequent increase of volume of the gypsum brought about the swelling up of the beds in cones and "boursoufllures." Then the
* "The Geology of Bolivia and Porn," by David Forbes, with notes on fossils, by Professor Huxley and J. \V. Sullcr, Esq., published by Taylor and Francis, Red Lion Court, Fleet Street, 1861, communicated to Geological Society in 1860.
t The saline springs of the Towala Mookhi and of Kangra-basa, in Kangra, issue from Saliferian ranges immediately covered by Miocene beds. Mr. Marcadien has found that the water of these springs contains Iodine, in addition to the usual saline matter of the Bprings of the Saliferian formation in Upper India. Vide Boport, No. 81, by M. Marcadieu. Sketches of Correspondence, Punjab, 1800.
•econd cause of disturbance began to act: the beds of salt are often dissolved and removed by water infiltrating through cracks in the rocks; a cavity is thus formed under the vault of rocks which covered in the salt and one day the vault falls in.
This process is to be seen now-a-days in actual existence, on a nnall scale, in the hillock of Maree on the Indus.
Thus, from the swelling of the gypsum by its transformation from anhydrite to common gypsum, and from the falling in of the vaults formed by this swelling, the beds of the Saliferian formation in the Punjab have a most broken and turned-over appearance.
Add to this that these beds have participated in the convulsions produced by the great final upheaval of the Himalaya, and you will lave no difficulty in understanding how difficult it is to make out with certainty the stratography of these rocks, and how it is that the Saliferian appears here and there inferior to the Palaeozoic beds. Before quitting the Saliferian formation, let us notice that the beds of it appear to have suffered very great denudation. We can easily understand that the red marl was very easily denuded, when we see how k crumbles into a powdery, friable, fluid earth, after a few days exposure to the atmosphere. It is on account of this denudation, on account of the very considerable amount of material which this formation gave to the Miocene and to the alluvinm deposits of Upper India, that the presence of Reh or Kullur in the soil of the Punjab and the North-West Provinces is to be credited to the Saliferian. I shall say a few words about this again, when we explain how the Miocene was made up, in the next chapter.
As there is yet such incertitude about the age of the salt, I have called the formation " Saliferian," without entering it on the Map as belonging either to the Palaeozoic or to the Mezozoic epoch.*
The carboniferous limestone is covered in, north of Vuicha, by an Oolitic formation of trifling thickness and containing Oxfordian forms.
* I have purposely avoided insisting on the mineral characters of the Saliferian formation of India, as it is now-a-days the fashion to undervalue very mnch these characters; bnt it may bo as well to remember that in the Bait Range wo have beds of gypBum full of rook-crystals of a bipyramidal shape; that the layers of gypsum aro soparated by calcareo-magnesian bands, having a cellular disposition (Cargneule of the Swiss, Rankwacke of the Germans) and that the salt is accompanied by a bright red marl witheut fossils. These several characters aro found in the Triassic salt and gypsum of Switzerland, of Savoy and of Spain, and, I believe, in no other formation.