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arranged in concentric caurellæ, and as these are decomposed from the cause already mentioned, the natural boulders are found. To find artificial boulders at great heights among the Himmalehs, is not uncommon ; there distribution, and how caused, we shall afterwards inquire. Vegetation in its distribution among the mountains presents very extraordinary characters-thus that of the south side of a hill is quite different from that of the north ; moreover the grouping of trees in the two aspects is quite different. On the northern they become much sooner shrubby, and disappear, than they do on the southern. This is amply proved by the observations of Mr. Gerard, for a copy of which we are indebted to Dr. Macleod.
Springs.-In regard to the temperature of springs, all those we met with were of the same temperature (or a little lower) than the surrounding air. Having made these few preliminary observations, which will prevent much repetition in the series of memoirs about to be offered, and of which this may be considered the first, in order to elucidate the geology of the Himmalehs, we shall now direct our attention more particularly to the subject. The rocks met with between Bhar and Simla, belonging to two grand divisions, viz. the secondary and transition classes, the latter, transition, may be subdivided into the older and newer, or the transition properly so called, and the Silurian formation of Murchison, a term lately given by this distinguished author to a series of slates, sandstones, and limestones, lying between the old red sandstone and grey wacke series, or, in other words, a mere extension of the latter, according to the views of Professor Jameson. To Mr. Murchison however much credit is due, for the able and luminous manner in which he has elucidated these rocks. By him they were first discovered in South Wales. In Scotland this so-called formation had been long known, though not considered entitled to another denomination ; they have also been discovered in various parts of the European continent. In Asia Minor, Mr. H. Strickland stated to us, that he had found a large series of rocks as their equivalents. In India they have never as yet been noticed, although they seem to occur in vast abundance among the Himmalehs, at the same time, exhibiting characters similar to those met with in Wales, judging from hard specimens.* Their extent we have not as yet been able to ascertain ; it must how.
The specimens we allude to were in the possession of our friend R. J. Hay Cunningham, who brought them from particular localities in Wales mentioned by Mr. Murchison. In the Museum of the Royal Society Edinburgh there is a collection presented by the discoverer; but so uncharacteristic, as to be quite unfit for reference.
ever be great, judging from the abundance with which they occur between Bhar and Simla. In Sect. I, which points out the formations generally, we have made no mention of tertiary rocks, not that they do not occur, but want of time, and the state of the weather, has prevented us, as yet, from examining them. From what has been stated by some authors, they seem to occur in great abundance in the Sewalick, or Sub-Himmaleh range, from whence the splendid fossil orgañic remains lately discovered (which have excited such vast interest in the scientific world), have been obtained ; with regard to these deposits, little satisfactory information has, as far as we know, yet been published. The fossil organic remains have received much attention from Falconer, Coulley, Baker, Colvin, and Prinsep, the last of whom, by his zeal, ability, and perseverance, has stirred up a spirit of inquiry, and given a stimulus to science in general, which before bis time was unknown; his loss to India at the present moment is truly a national one. By several individuals splendid collections have been transmitted to Europe, among which we may mention those of Colvin and Macleod. In the Palæontology* of this country, still, however, there remains a vast deal to be done.
At Bhar, the secondary rocks we meet with consist of sandstone, slate clay, and trap. As we proceed eastward to Bunnassur we meet with the same rocks, having a dip S. and by E. with an angle varying from 15° to 50°. The trap (green stone) abounds with iron, giving the rocks in many places a reddish brown colour. The same remark applies to the slate clay, which in many places is much decomposed. At the line of junction of the sandstone and slate clay with the trap, they are frequently found to be highly indurated; of this appearance we have many fine examples at Bunnassur. The sandstone, which is in general of a greyish white colour, abounds with mica, giving it in many places a slaty form ; this variety is the micaceous sandstone of some authors. In the locality just mentioned, I found a large calamite in the sandstone, and in the slate clay at a short distance from it a fern and seed. The iron which occurs disseminated through the wackes is the red iron ore, or red hematite, in too small quantity however to be of any economical value. In proceeding
* Since the above was written, we have seen the splendid collection of Capt. Baker at Dadoopoor. In it we saw several specimens which could not be referred to any of the animals already described, no doubt quite new species; one, of which however there was only a fragment, seemed to belong to a genus hitherto unnoticed, approaching in several characters to one of the genera established by Cuvier, probably forming one of the connecting links.
from Bhar towards the Fir-tree Bungalow, we meet with much trap (greenstone) breaking through in every direction, and altering the Neptunian secondary strata, rendering their examination rather intricate. In proceeding from Subathoo to the eastward, towards the village of Draw, we have a fine example of the coal formation presented ; opposite to this village we meet with limestone dipping to the S.W. under an angle of about 50°. Resting upon it, there is a bed of slate clay, and upon it, another bed of limestone ; proceeding towards the westward we meet with sandstone, and resting upon it limestone ; succeeding it, slate clay and bituminous shale. At the village of Koli we again meet with limestone, and as we proceed, following the same route, passing the villages of Benti, Rugg, Gegutkun, Shulkiali to Boag, we meet with other ten similar alternations, (see Sec. II). The beds have all the same dip, the angle varying from 250 to 56o. At Draw there is a water-fall, which is precipitated over the lime. stone cliffs. The whole face of the cliffs here, and along the route just mentioned, having a height varying from about 150 to 200 feet, are more or less covered with calcareous sinter and tuffa, shewing, as these minerals are deposited from water, that water-falls must at one time have been general in this district. Resting upon the limestone at Draw, and in one or two other localities, we meet with an extraordinary alluvial conglomerate, composed of small angular fragments of limestone, slate clay, bituminous shale and sandstone, held together by calcareous matter deposited from the water; whether the calcareous matter is deposited by springs issuing from the limestone rock, we are unable to state, our examination being of such a cursory nature; it is however more than probable. To account for goitre, various theories bave been proposed, and the one, viz., that it is owing to mineral matter (lime) contained in the water of which the inhabitants drink, has been adopted, and strongly advocated by many medical men in this country. According to this theory it ought to be very prevalent in this neighbourhood. That this explanation will account for the disease in many localities, is no doubt probable; but how are we to explain its occurrence, and that too, to a great extent in primitive districts, where the only rocks met with are gneiss, mica, slate, clay slate, and granite, and in all the springs in which no lime has been detected ; moreover, in many districts in Britain and on the continent of Europe, composed entirely of limestone, and in whose springs lime abounds, goitre is unknown. We shall afterwards enter fully upon the subject, when we have examined among the Himmaleh districts, similar to the above, of which there are no doubt many. In
the meantime we beg to draw attention to the villages occurring between Boag and Draw, in order that it may be proved whether goitre is prevalent or not. In its characters, the limestone varies from compact to earthy, the latter caused by the action of the weather; its colour varies from greyish white to bluish black, and in many places we find large embedded masses of stinkstone, of a dark greyish brown colour, or rather we ought to say, that the limestone during its deposition, has, by the evolution of sulphurated hydrogen, been converted into this mineral ; when broken, the føted odour is strongly perceptible. For architectural purposes, and as a top dressing when burnt, to soils containing the salt of iron, or any acid matter, this limestone is admirably adapted. In this manner many of the soils in India might be much improved. In structure, the slate clay and bituminous shale vary much; in some places indurated, in others partly decomposed. Their colour also varies much ; of the former the most prevalent colour is greyish black, of the latter, brownish black ; sometimes the slate clay, owing to the abundance of iron, is of a reddish brown colour. At the village of Boriti the slate clay has an angle of 70°, and is much contorted; near to this there is a thin bed of slate embedded in the sandstone. In regard to the rocks of the coal formation here, and those of other localities already mentioned, we may state (as we have already done generally) that they present the same mineralogical characters as those rocks, occupying a similar position in Europe. The true position of the coal measures, which has frequently been given erroneously by authors in this country, is when the geological series is complete between the red conglomerate and mountain or carboniferous limestone; the former the Rothibugende* of the Germans is frequently wanting; when this occurs, we have the magnesian limestone superimposed upon the coal measures. In a work Jately published on Indian Geology, it has been stated, that the magnesian limestone occurs, alternating with the coal strata. As such a statement is very apt to lead to a serious error, we have been induced to notice it. The rocks which the author has found, are merely the limestone of the coal formation, impregnated with magnesia ; and it is a fact, proved by a vast series of experiments, that when the coal or any other limestone comes in contact with trap, it generally receives a large dose of magnesia, sometimes as much as 35 or 40 per cent.* Moreover in a practical point of view, it is of the greatest consequence to distinguish these two rocks, as coal never occurs associated with the magnesian limestone, properly so called. In the same work the author talks about the discovery of shell limestone in the coal formation ; no doubt he discovered limestone with shells, which frequently abound in the coal limestone; the other term however is strictly applied to a rock which is much newer and of rare occurrence, which has not as yet been met with in England. Murchison, however, has stated, that he has found its equivalent on the European continent; it occupies a position between the red marl, and the new red sandstone. It is the Muchelkalk of the Germans. To distinguish therefore between these, and at the same time to apply their proper names, is of consequence, which can be easily done by examining the fossil proper to each ; characteristic of the latter, we have Encri nilis, Monitiformis, Avicula, Socialis, and Ammonites, Nodasus, &c., and of the former Producta Serebralulæ, or the Ceratitis, &c.
* In England it is sometimes termed the Exeter red conglomerate. In Scotland it has never been met with.
There is another circumstance worthy of notice here, viz. Red Sandstone. It is not to be supposed that when sandstone is of a red colour, it must always belong either to the old or the new red sandstone, an erroneous idea which has led to many errors, and much censure by foreign geologists. To find red sandstone alternating with the white sandstone of the coal measures (a fact which ought to be recollected by individuals engaged in searching for coal in this country,) in Europe, is not unfrequent. In lower Silisia nearly the whole of the coal field is composed of reddish brown, and cochineal coloured sandstone, with which great beds of coal alternate.+ In Scotland, in the Lothians, alternations of the red and white sandstone in the coal fields are frequently met with. This rock (red sand. stone) seems to occur in great abundance in this country; its relations, however, have not been properly investigated. In a report drawn up for the Coal Committee by Dr. M'Clelland, there is much interesting information in regard to it; of the rocks which enter into the composition of the coal formation, we have already mentioned as occurring among the Himmalehs sandstone, slate clay, bituminous shale, and limestone. To make the series complete, we want, fine
Edinburgh New Phil. Journal. Analysis of Limestone from the neighbourhood of Trap Dumifrieshre, by William Copland, Esq. In the same Journal many similar analyses will be found, † Notes to the Geology of Dumfrieshire, by Professor Jameson, Ibid. Locis Citatis and Cunningham's Essay on the Geol. of the
Trans vol. VII.