In the present instance the chief object having been the formation of an appropriate bed of earthy soil, to receive and sustain that rich and magnificent vegetable covering composed of an attractive variety of foliage, of flowers, and of fruits, which was so soon to be thrown over and to adorn the new-formed land. I refer the reader, first of all, to the statement in the ninety-eighth Theorem.* When we reflect on the stupendous chemical process then going on, the introduction of heated continents and mountains abounding with metals and metalloids into the midst of a universal ocean, plentifully saturated with oxygen, and take into account the increased powers of oxidation which water possesses when its associated oxygen is augmented, we are forced to exclaim, This indeed was a laboratory worthy of the Creator, when producing the materials for the soils of a world! Any observations here on a subject such as this would be wholly superfluous. To those who can appreciate its magnificence they will be unnecessary; to those who cannot they would be of no avail. I shall, therefore, go on to exhibit the manner in which these earthy oxides are generally removed from where they are formed; and, last of all, enumerate the remaining substances which contribute to the formation of perfect soil. With respect to the material itself, please to refer to the hundred and fourth Theorem.† Bearing this information and that which has been acquired in the previous chapters in mind, and applying both to the operations going forward on the first and second days of the Mosaic week, it will be acknowledged, that every requisite element was present for the production, in the shortest possible period, of a quantity of silicious and calcareous materials, which, when joined to the débris spread abroad by the explosion of the protruded rocks, when they burst through the superincumbent strata, would be sufficient to form, by subsequent but almost immediate deposition, those unconformable suites which overlie the coal measures-the remains of the submarine vegetation of the primitive world-and also other portions of the original surface. Therefore, in pursuance of the method hitherto observed, it is only now requisite to inquire whether geologists recognise any formations, whatever be their denomination, which correspond in character to the material here supposed to have been spread abroad. If we set aside, for the present, the limitations imposed by the nomenclatures of the various geological systems, and take a comprehensive view of the mineralogical and geological characteristics of these formations themselves, there will be discovered, with peculiar satisfaction, in the proofs which geology affords, a striking corroboration of the opinions which have been expressed, so much so, indeed, that the substance of the following evidence may be summed up in one brief sentence, namely, every formation superior to the carboniferous group and those of the same era affords evident symptoms of having been deposited from a heterogeneous mass of mineral débris, occasioned by some great and general catastrophe; while the coal series themselves, with the mountain limestone and old red sandstone which underlie them, exhibit as evident symptoms of having together undergone some violent movement about the same period. To prove this, I shall now commence a new series of inquiries, beginning with what is contained in the thirty-first Theorem, to which please refer.* In support of these opinions Dr. M'Culloch expresses himself thus "The coal series, which have been called independent, occupies a geological position superior to the old red sandstone, and inferior to the new one, or to the red marl. . . . . . As the beds of coal are found accompanying and alternating with stratified rocks, so they are also disposed in strata parallel to them. These strata are in every respect analogous, in their forms, dispositions, and accidents, to those of the rocks with which they occur. In position, they are horizontal, or inclined at various angles, often highly elevated, as in the whole series. . . . . . The thickness of a coal stratum varies, even from less than an inch, to ten or twelve feet, but it rarely exceeds two or three, and is, more often, much less; and thus particular strata become attenuated till they disappear. "Now, it is essential to remark, that the old red sandstone, the mountain limestone, and the coal series are all disturbed, being elevated, undulated, and fractured in various ways. . . . . . And it must, similarly, be recollected, that a new order commences with the 31st Theorem. magnesian limestone and the red marl; or that they are placed on the coal series, and the inferior strata, in an unconformable position, while the lower substance also presents that conglomerate structure, which everywhere throughout nature accompanies a new order in rocks." * "It was not enough," observes Professor Buckland, when treating of the carboniferous series, "that these vegetable remains should have been transported from their native forests, and buried at the bottom of ancient lakes, and estuaries, and seas, and there converted into coal; it was further necessary that great and extensive changes of level should elevate, and convert into dry and habitable land, strata loaded with riches, that would for ever have remained useless, had they continued entirely submerged beneath the inaccessible depths wherein they were formed; and it required the exercise of some of the most powerful machinery in the dynamics of the terrestrial globe, to effect the changes that were requisite to render these elements of art and industry accessible to the labour and ingenuity of man. "The place of the great coal formations, in relation to the other series of strata, is shown in our first section; and they are represented as having partaken of the same elevatory movements which have raised the strata of all formations towards the mountain ridges, that separate one basin from another basin. . . . "This disposition in the form of troughs or basins, which is common to all formations, has been more particularly demonstrated in the carboniferous series, because the valuable nature of the beds of coal often causes them to be wrought throughout their whole extent." t 66 "This valuable series of strata, the carboniferous system," says Professor Phillips, to which Great Britain owes so much of her commercial prosperity, is extended irregularly over the basins of Europe, North America, Australia, &c. It occupies large breadths in Scotland, Ireland, England, and Wales, and lies in patches in various quarters of France, Germany, Poland, and Russia. Commonly it is found at the foot or on the flanks of primary mountains which had been previously uplifted, so that its stratification is not in accordance with theirs. .. "The variations in the development of the carboniferous system are considerable, and its occurrence is often in detached portions; it is, therefore, requisite for obtaining a general section, to combine the results of different and independent observers. . . There are three great formations included in the carboniferous system, which is three thousand feet thick in the North of England, consisting of abundance of sandstone and shales, layers of ironstone, and beds of coal." And then follows, after the mountain limestone formation- *Geology, vol. ii. pp. 299-304. Bridgewater Treatise, vol. i. pp. 525-527. "The old red sandstone formation, varying in its character so as to offer little that is really of general application, except its colour and the absence of coal, and rarity of limestone." Mr. Phillips goes on to say "After the deposition of this system, and before at least any considerable proportion of the superjacent rocks was formed, very extensive displacement happened in most parts of the surface of the globe where the carboniferous rocks have been deposited. Hardly a known coal tract being exempt from this influence, it would appear that convulsive movements took place of a very general description, so as to affect very large tracts of the surface of the globe. In the British Islands, every coal district is disturbed and shaken in every square mile of its breadth by faults (gauls, slips, troubles, and dykes'), passing in many directions, some of them having a great amount of throw,' and consequently affecting the working of the mines. But these minor effects lose their importance when we contemplate the gigantic disruption of Tynedale, the Pennine chain, the Craven fault, the Derbyshire elevation, the fault of the vale of Clwydd, the double anticlinal axis of the coal-fields of South Wales, and the parallel one of Namur. . . . . North of the Tynedale fault, is a depression or throw of 1,000 to 2,000 feet; west of the Pennine fault, 2,000 to 3,000, or perhaps 4,000 feet under Crossfell; and south of the Craven fault, 3,000 feet at least near Ingleborough.' These interesting and appropriate evidences will be brought to a point by a short extract from Mr. Hugh Miller's work on the "Old Red Sandstone," assured that, together, these various quotations are quite conclusive with respect to the subject under immediate consideration :— "Is it not a curious reflection that the commercial greatness of Britain in the present day should be closely connected with the towering and thickly spread forests of arboraceous ferns and gigantic reeds, vegetables of strange forms and uncouth names, which flourished and decayed on its surface, age after age, during the vastly extended term of the carboniferous period, ere the mountains were yet upheaved, and when there was as yet no man to till the ground?"† After the perusal of these extracts, the mind may be considered to be prepared for entering, with more effect, into the examination of the very interesting section of geological research comprising the several groups up to the chalk inclusive, which unconformably overlie the coal measures. This latter being considered by the Dynamical System to have been the last, or most recent, deposit of the non-rotatory earth, it follows, that all those just mentioned, namely, the + Old Red Sandstone, pp. 233, 234. A A * Treatise, pp. 100-106, 112, 113. New Red Sandstone, the Oolitic, and the Cretaceous groups, are looked upon as having been formed by the débris spread abroad by the first diurnal rotation of the earth around its axis. Before, however, entering upon the investigation of the new red sandstone group, it may be opportune to remind the reader of a former advertence, "that the explanation of the nature and origin of the saline deposits, so universally associated with this particular series, is reserved for a future part of this work; it being necessary to explain the formation of the atmosphere, and the manner in which the water was separated from the land, before these saline depositions can be satisfactorily accounted for. I beg reference to the thirty-second Theorem, and to the following evidences in support of the opinions stated therein : "We now arrive," Dr. M'Culloch says, " at the magnesian limestone of the English series. A new order of arrangement here begins to be observed among the strata, whence we may take a fresh departure. It is not meant to say, that the red marl, much less the associated inferior limestone, is invariably present, even in Europe where it is known to occur; but if there is any series truly entitled to the character of regularity, as well as universality, using that term in the general sense formerly stated, it is this one."* And again "It is not always possible to distinguish the three red sandstones, except by careful geological investigations, since the mineral distinctions give but little assistance; the alternation of the primary sandstone with gneiss, or other primary strata, is an infallible geological criterion for that rock. With respect to the red marl, the presence of salt is equally infallible; that of gypsum is a good test, if not absolute. Its superiority to the coal series is another, as is its immediate inferiority to the lias limestone. . . . The sandstone under review appears to be one of the most generally diffused rocks in nature; and may thus be considered, like gneiss, among the deposits commonly called universal. . . . . . But that which distinguishes this deposit (upper sandstones) from all the secondary sandstones, is the presence of rock salt. . . . . . It is the proper or even exclusive repository of salt, although the mineral occasionally passes beyond the rigid boundaries, on both sides, so as to appear in the magnesian limestone below it, and in the lias above."t "These dissimilar conditions of three great divisions of our country," says Professor Buckland, "result from differences in the geological structure of the districts through which our three travellers * Geology, vol. i. pp. 274, 275. Ibid., vol. ii. pp. 214, 228. |
