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In regard to simple minerals met with imbedded in the rocks, our list is but small, consisting of
Red and brown Hematite. In addition to the localities mentioned of the iron ores, Dr. Macleod pointed out to us several masses in the bed of the river torrent in Simla valley, shewing probably, as the fragments were angular, that a vein, or veins, occur near, of little value, however, from their impurity. In regard to the garnets, it is rather a remarkable fact that we have only met with them in those localities where the clay slate appears to have been much altered ; the same has been remarked in Europe by Sedgwick, and Lyell. As yet we have no account of the minerals met with among the Himmalehs ; those already noticed amount to not more than twenty or thirty, a statement truly remarkable, pointing out how lamentably this department has been neglected; in such a mighty range we ought to meet with an immense number of minerals. In the collection of the Asiatic Society of Calcutta, we found several minerals which have never as yet been noticed as occurring in India ; but whether these were found in this country, or imported, is a ques`tion, no labels being attached, and Mr. J. Prinsep in England. Cal. careous spar occurs frequently in the form of veins in the clay slate. of the other minerals mentioned, the localities have already been given.
Having now noticed, both generally and particularly, all the rocks and minerals which have as yet come under our observation, we shall make a few remarks in regard to that formation (the most important of all formations) which forms such large tracts of the Himmalehs; I allude to the coal formation. From what has been stated by authors, and from what we have already seen, it is not at all improbable that there is a belt composed of those rocks, extending along the whole base of the Himmalehs proper. The furthest point, to the westward of which we have notice of these rocks, is At. tock, and to the eastward, probably Darjeling; comprehending about 17° of longitude; that, however, it extends further in both directions, is more than probable. That no bed of coal worth working has
Near Subathoo imbedded in the slate, sulphate of lime or gypsum is found. From this rock the celebrated Plaster of Paris is made.
been met with in such a vast tract of country, results not from its absence, but, probably, from the partial manner in which the country has been examined. Captain Herbert in one of the vols. of the Asiatic Society's Trans. has given a paper on the occurrence of coal in the Indo-Gangetic mountains, in which he comes to the conclusion, that all the sandstones and other rocks noticed, belong to the red wacke series, but from data utterly groundless; and remarks in regard to the probability of finding the coal formation, that the indications are unfavourable; we shall however quote his own words—" it will be perhaps asked,” he says, “is this coal, of which the traces are probably widely diffused in our sandstone range, likely to prove
any value, or do these many indications afford any ground to hope for the discovery of more extensive and profitable deposits ?” To this it may be replied, that the considerations upon which are founded the hope of discovering, in the neighbourhood of these mountains, the true coal formations, are quite independent of its occurrence under this type and in this form; if any thing perhaps, they are rather unfavourable to the expectation of eventually discovering beds of the true coal formation, for it has been noticed, that in those countries in which the coal beds are most largely developed, as in England, the traces of the mineral in the superincumbent sandstone are rare, if not altogether wanting ; while on the continent, where the true coal beds do not occur, small seams or veins are frequently met with in this rock. To find traces of coal in superincumbent sandstone, in districts where coal has not been found, is one of the strongest evidences, if not the most important, that coal is present. In fact nothing is more common in a coal district, than to see disseminated through the sandstone, or occurring in small seams, coal prior to reaching an important bed; we may state that from it we are entitled to infer, that if a shaft is sunk sooner or later, we shall arrive at the bed of coal. In examining a coal district, advantage should be taken of all the streams that occur in a district, for by so doing, a transverse section of the strata is obtained, and frequently thus the outcrop of a bed of coal is perceived. It is also of importance to examine the masses which occur in the stream, coal in such localities, frequently occurring at a considerable distance from the bed in situ. If the remarks of Captain Herbert were applicable, all the observations made by geologists, mining engineers, &c., would be void. In the same paper we are told, that grey wacke is considered as synonymous with the old red sandstone by most geologists; who these geologists are he alludes to, we do not know. Also that at Delhi
and other places there is a primary sandstone ; we take notice of these statements, in order to shew that Captain Herbert made the above statements prematurely. It is impossible for any individual at all acquainted with the mineralogical characters of rocks, and the rela. tive position which they occupy in the crust of the earth, to attempt to prove that in one continent rocks with identically the same characters and fossils, are different from those in another. To find slate clay, bituminous shale, limestone, and sandstone, as the equivalent of the red marl, upon the evidences he has given, is more than premature, originating however, in all probability, from the description of the rocks in the Punjaub, which (probably without a proper examina. tion) have been considered as the continuation of those to the eastward. It has been stated no doubt that no bituminous shale occurs, but we have shewn that it, as well as limestone, occurs in great abundance, the former of which rendering the probability of the existence of coal in quantity, more probable. That the equivalent of the red marl may be found, and that too in some of the districts mentioned by Herbert, is possible; and if such should turn out to be the case, it is well worthy of examination, seeing that it is in this formation, the great beds of rock, salt, and gypsum, or sulphate of Jime are found.
To discover coal in quantity in the neighbourhood of the Sutledge, or any place where there is easy access of carriage in that direction, would no doubt, in a short time, be of incalculable benefit to the country at large. In a short time the Indus will become an immense resort for trade, and we may expect it soon to be covered by all kinds of vessels ; but those to which the European looks forward, whose power and rapidity of motion have so approximated Europe, will ever take the lead; and until stream vessels are impelled by some other moving power, coal will ever be considered as one of the greatest benefits conferred on mankind; moreover in connexion with the coal we may expect to find clay iron-stone, which will also prove of the utmost consequence. It is from this ore that three-fourths of the iron is obtained in England. It has been met with at Darjeling, and several other places in India, but from the want of fuel and flax to reduce it, we do not think it has ever been made use of. If however we look at the mineral resources of this country, what are they at the present moment? nothing to what they ought; a spirit of inquiry is now happily gaining ground ; sanctioned by Government a coal committee has been appointed. To its proceedings therefore we look forward