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EXTRAVAGANT SPECULATIONS OF PLAYFAIR.
thence elevated by catastrophe into the present dry lands. Their marine deposition was slow and tranquil, disturbing the general economy of nature no more than at present, and consequently, not interfering with the production of marine testaceous animals, nor with the distribution of their shelly exuviæ. Hence, should these beds be eventually indurated and heaved up by the subjacent fires into the nearly vertical mountain schists of a new earth, they must contain the organic witnesses of their submarine formation. But since our actual mountains of gneiss and micaslate are destitute of these internal witnesses, as also of their basis, carbonate of lime, they cannot have been ormed at the bottom of an ocean teeming with animal life. Devoid of organic remains, they indicate a sea devoid of vital energy. The first appearance of shelly strata is coincident with a specific exertion of creative power.
This mortal chasm, in the succession of mineral formations, breaks the chain of the Huttonians. It is the death blow of their theory; demonstrating that the present earth has resulted from definite creative Fiats; and not from the progressive operations of any merely physical forces whatsoever. It is therefore to be regretted, that a mind so accomplished as that of Professor Playfair, should have devoted so many studious years to the decoration of the phantom described by him in the following paragraph.
"How often these vicissitudes of decay and renovation have been repeated, is not for us to determine; they constitute a series, of which, as the author of this theory has remarked, we neither see the beginning nor the end; a circumstance that accords well with what is known concerning other parts of the economy of the world. In the continuation of the different species of animals and vegetables that inhabit the earth, we discern neither a beginning nor an end; and in the planetary motions, where geometry has carried the eye so far both into the future and the past, we discover no mark either of the commencement or of the
termination of the present order. It is unreasonable indeed, to suppose, that such marks should any where exist. The Author of Nature has not given laws to the universe, which, like the institutions of men, carry in themselves the elements of their own destruction. He has not permitted in his works any symptom of infancy or old age, or any sign by which we may estimate either their future or past duration. These phenomena then are all so many marks of the lapse of time, among which the principles of geology enable us to distinguish a certain order, so that we know some of them to be more, and others to be less distant, but without being able to ascertain with any exactness, the proportion of the immense intervals which separate them. These intervals admit of no comparison with the astronomical measures of time; they cannot be expressed by the revolutions of the sun or the moon; nor is there any synchronism between the most recent epochas of the mineral kingdom, and the most ancient of our ordinary chronology.'
Our ordinary chronology comprehends the deluge, a great epocha of the mineral kingdom, the truth of which is obviously discarded by Mr. Playfair. In the third part of the present work, ample evidence will be adduced from Cuvier and other practical naturalists, of the reality of that recent epocha, and of its synchronism with our chronology. Moreover, it will be shown in our second part, that the mineral strata contain formations which "discover marks of the commencement" of the different species of vegetables and animals that peopled the earth. The Astronomical comparison is a strange solecism for so acute a logician to commit. The cases are quite discrete, and destitute of any true analogy. The laws of the planetary motions are represented in a system of mechanical theorems, which relate solely to co-existing phenomena. The principles of their actual equilibrium apply equally to all past and future
* Playfair's Illustrations, § 118 and § 124.
GEOGNOSY OF WERNER.
time. The appearances reveal nothing in the past, or the future, different from the present, except change of relative position among separate masses. The physical constitution of the planets, which could alone afford, in their interior metamorphoses, kindred or parallel facts for geology, are beyond our cognisance. In the mineral structure of the earth, we shall find symptoms of infancy, as well as on its surface, considered as the dwelling place of man.
A very brief survey of the principles of the Neptunian theory of the earth, will evince it also to be an idol set up by a vain philosophy, to usurp the rank and functions of a creative intelligence.
"Anciently," says Werner, "a vast solution covered all the globe, rising above the highest mountains. This great chaotic ocean, very different from our existing seas, contained the elements of the primitive lands. The most ancient of its products, namely, the rocks on which all the others repose, are also those which constitute the most elevated summits; those which form the greater part of the most prominent points of the globe, with the exception of the volcanic mountains. Over and around their tops, we find the mineral masses which were deposited imme diately thereafter. They envelope the former in the shape of beds of great extent, and they are enveloped in their turn by other beds. In proportion as these deposits are newer, their extremity or upper edge, appears at a lower level.
"Thus, above a certain height, we find nothing but granites; a little lower we have gneiss; lower still, we see the successive appearance of mica-slate, clay-slate, and the other primitive formations. Those of posterior formation proceed with a continually declining level. The most ancient of these still stand at considerable heights; but the more modern, such as chalk, and the later formations of gypsum, occupy only the lower districts of the terrestrial surface. Finally, the great alluvial territories exist merely in the low plains, or at little elevations above
the level of the sea. These facts lead us to conclude that the solution, in whose bosom the different mineral masses were elaborated, has successively lowered its level; and that from an elevation above our highest mountains, a gradual diminution has reduced it to the level of our present seas." In the later geognostic works published in Germany, on the principles of Werner, the several mineral formations are regarded as having been produced by four great irruptions and subsidences of four successive seas.
"The above solution successively changed its nature. Its first mineral precipitates were very different from the following ones; and these also differed from their successors. At the beginning, they were chiefly granites; in the middle period of the mineral formations, schistose or slaty strata abounded; and in the last stage, calcareous rocks began to predominate. The change in the nature of the precipitate was sometimes abrupt, but more commonly it took place in gradual succession. Thus, among the first mineral formations, the principles of felspar were most abundant; these diminished by degrees, while those of mica increased ; and in consequence of this alteration, gneiss, mica-slate, and clay-slate appeared. The limestone, which was rare in the early stage, occurred subsequently in more abundance, forming the principal ingredient of the later deposits. Magnesia became remarkable, chiefly towards the middle of the first period; some time after that, coal began to show itself, and progressively increased in the middle era.
"While the solution covered and enveloped the whole surface of the globe, it formed a clear and tranquil liquid of great depth. At this time, its products were entirely crystalline. Thus, when we contemplate a piece of granite, and examine the distinct grains or small crystals of quartz, felspar, &c. which compose it, the segregation and arrangement of their integrant particles denote a mineral formation made with leisure and tranquillity.
"In proportion as the level of the liquid sank down,
WERNER'S FORMATION PHANTASMS.
the agitation appears to have augmented. The crystallisation became confused; the particles had no longer an opportunity of coming forth separately, as in the first epocha, so as to form considerable crystals. Hence arose those finegrained granites which form the paste of porphyries; those mica-slates in which the grains of quartz, and the spangles of mica are amorphous, and are difficult to distinguish. Finally, chemical separation ceased to take place, or be practicable; the crystalline aspect disappeared, and nothing but homogeneous masses were produced, whose texture became more and more loose and earthy, till their translucency vanished. The serpentines, the slates, and even the limestones furnish examples of these gradations. At last, the turbidity having increased to a still greater degree, and the precipitation becoming more rapid, the mineral deposits became mere earthy masses, feebly indurated; they were now simple sediments.
"Werner supposed that frequent oscillations had modified these successive formations. Before the large grained crystalline granite had passed into schists of a clayey or sedimentary quality, nature often retraced her steps for a season. After making mica-slates, and even clay-slates, she thought fit to reproduce some granites; and it was not till after several such alternations, that she advanced in a decided manner, to form the great schistose mountains.*
I believe this outline of Werner's theoretic notions to be genuine. The authority is apparently most legitimate, that of his favourite pupil, M. D'Aubuisson, engineer in chief of the royal corps of mines in France, "who was honoured during four successive years with the confidence of his master, Werner, and favoured with a disclosure of geological principles which he himself never submitted to the press." It would be superfluous, indeed, to offer an elaborate refutation of a world-building hypothesis, so extravagant,
* D'Aubuisson Traité de Géognosie, Tom. I. pp. 355, et seq.