If now we examine the facts and arguments tending to show that the land has been thrown up from the bottom of the sea, we shall find that the evidence amounts to little less than absolute demonstration that this has been the

In the first place, strata composed of fragments of rocks of any considerable size will take the horizontal direction. It is true that deposites of fine matter, as clay, and sand, from water, will at first take the impression, or form of the bottom when this is uneven, but if the strata be of any considerable thickness, the layers will assume a horizontal level. But we shall find on examination, that very few stratified rocks in any part of the world, have preserved their coincidence with the horizon. On the contrary, they are inclined at various angles, and are sometimes even quite vertical; clearly evincing that they have been disturbed, and dislocated by some violence, since their formation.

ena.

"If," says Dr. Macculloch, "the highly inclined position of strata were not itself a proof of their elevation, evidences of motion are found in a great number of phenomIn their curvatures we find proofs of disturbance; we find even more decided evidence to the same purpose in their fractures. But when we see that these fractures are accompanied by a separation of parts which were once continuous, that one portion of a stratum occupies a higher or lower place than another, and that this separation is often attended by a difference in the angle of inclination of the separated parts, we have every proof that can be desired, of an alteration in the horizontal position of stratified rocks, since the period when they were consolidated."Geology, vol i. p. 88.

In the kind of materials of which many inclined strata are composed, we have additional evidence of their elevation.

We have stated that depositions of sediment from water will at first take the form of an uneven bottom; but we need not stop to prove, that fragments of rock of any considerable size will not rest on the sides of steep declivities, but will roll or slide down by their own gravity. Now, "it is notorious," says Dr. Macculloch, "that the conglomerates which form such conspicuous strata in many countries and which prevail chiefly at the boundary which separates the strata called secondary, from the primary, are

often found in positions, not only highly inclined, but absolutely vertical. As the materials of these are often of such bulks as to weigh even many hundred pounds, it is evident, that the original position of the strata which contain them must have been horizontal."

It is well known also, that certain marine worms which live in sand, and inhabit straight tubular shells, invariably penetrate the sand in a vertical direction, whether the surface be horizontal or not. If the strata remain undisturbed these shells remain in the position seen at Fig. 12.

Fig. 12.

a

And it needs little reflection to see that a concave, or dish formed shell, when it sinks in water, must reach the bottom with its convexity downwards, and hence in all recent formations, such shells are always found in this position. But in the inclined strata, of which we are speaking, such tubular shells are found making various angles with the horizon, though they preserve their perpendicu larity with respectto the strata: as represented at b. Fig. 13,

Fig. 13.

while had the strata been pierced after its disturbance, it would have been in the direction of c.

The

concave shells, under like circumstances, are found to have changed their positions, their cavities being no longer upward, but inclined acOn the same sub

cording to the position of the strata. ject Dr. Ure says, "the erection of subaqueous strata into primitive mountains and plains, was evidently accompanied with universal disruption. Innumerable fragments of both the upborne, and upbearing rocks, were tossed about and washed down into the congregated waters, along the precipitous shores, and over the beds of the primeval ocean. These shattered fragments becoming agglutinated by their own pulverulent cement, soon recomposed continuous strata, which bear internal evidence of the violence which gave them birth. Thus were formed the transition rocks of geologists, mineral masses which denote the passage between the upright primitive, and the horizontal secondary strata, between those of inorganic and organic evidence."

The convulsions which after a long interval caused the deluge, have dislocated many of these conglomerates, so

Fig. 14

that strata of rounded pebbles assuredly agglutinated in a horizontal position, are now found standing in upright walls. Thus the famous pudding stones of Valorsine in Savoy, are a kind of greywacke schist, containing rounded fragments of gneiss and mica slate, six or seven inches in diameter. That stones previously rounded by attrition, should build themselves up into a nearly perpendicular wall as seen at Fig. 14, and stand steadily thus, till fine particles of hydraulic cement should have time to envelope and fix them in their places, is an absurd and impossible supposition. It is therefore demonstrable that these pudding stone strata were formed in horizontal, or slightly inclined beds, and erected after their accretion. Such effects would be produced, in the convulsive emergence of the pebbly banks out of the primeval ocean, either at the deluge, or by some preceding catastrophe. There are mountains 10,000 feet high, in the Alps, formed of firmly conglomerated pebbles.

Another and most striking proof that the rocks have been elevated by some force acting beneath them, is exhibited by primitive, mountains in various parts of the world.

Here we find granite in the centre, with stratified rocks, as gneiss, mica-slate and clay-slate, leaning against its sides, sometimes nearly in a vertical position. Now as these stratified rocks must have been deposited on a horizontal level, or nearly so, and surely not in the highly inclined positions in which they are found, it is evident that their original positions must have been changed, and their inclinations caused by the same force which elevated the primitive mountains.

Under the article "Classification of Rocks," this subject is illustrated by a wood cut, to which the reader is referred.

It thus appears sufficiently evident, that at least a great proportion of the habitable earth was formed in strata under the sea; and that subsequently to its being consolidated chiefly in the position and form of horizontal layers, it has been violently elevated above the water, by

some tremendous subterranean power. Hence the strata are found oblique, dislocated, and rent asunder in nearly every part of the world; and from this cause it is, that the sea and land have exchanged places, and the mountains have been elevated; but to the same cause, even to the destruction of that continuity and harmony which seems to have existed in the form of the primitive globe, we must attribute many of the greatest conveniences and comforts which the present earth affords.

Had no disturbing forces interposed, there is reason to believe that the inferior strata, now in many places elevated into hills and mountains, would forever have been concealed from the knowledge of man; for was the earth every where covered with horizontal strata, lying in regular layers, one upon another, the same kind of formations would every where exist; and of which we should know nothing below the depth of actual excavations. Metallic veins, salt, and coal would afford no indications of their existence at or near the surface. There would have been no mural precipices, or mountain declivities, or outcroppings of strata, by which the geologist, or practical miner would be enabled to judge of the interior. Nor would there have been any spring of water issuing from the surface of the earth, for it is the inclination of the strata which directs the water to the surface, and its unevenness which allows it to break forth in the form of springs. In plain level districts, no water rises to the surface. In these, and many other examples which might be noticed, we cannot but see the traces of benevolence and design, even in the "wreck of matter" which this earth every where displays; and which at every step, forces us to acknowledge, not only the Power, but the Wisdom and Kindness of the Almighty Builder of this our habitation.

With respect to the agent which has thus thrown mountains and continents from the depths of the oceans, and has dislocated the frame work of the globe, we can conceive of none except volcanic, of sufficient power to produce such effects. It is true that no continents or extensive mountains, have been elevated from the sea, since the historical era, but we have a sufficient number of examples of the effects of this power, even during the present age to shew that the established order of nature would not be changed by the elevation of a continent,

The elevation of land to the extent of a hundred miles on the coast of Chili; the rising of the Sabrina island out of the ocean; and of the Aleutian islands on the coast of Kamtschatka, out of the same—the changes made by the force of volcanoes in the neighborhood of Naples, and the effects of the earthquakes of Calabria and Lisbon, (all of which we have described in the preceding pages,) afford analogies by which it is not unreasonable to conclude, that it was the same kind of force which broke in pieces. the crust of the primeval globe, and raised the habitable earth from the ocean's bed.

At what period of the creation these great changes took place, we must remain in ignorance, but it is improbable that they were all effected at the same time. On the contrary, the appearance of the strata seem to indicate a succession of revolutions at different, and perhaps remote periods from each other. These revolutions appear to have been before the creation of man and animals, and probably by such means did the Wisdom and Benevolence of the Creator prepare a place for their reception and comfort.

CLASSIFICATION OF ROCKS.

The most simple division of rocks is into Primitive or Primary, and Secondary. The first consisting of those which are supposed to have been originally formed, such as granite and its associates, and the second such as were formed by the disintegration, or destruction of these. In the early state of geological knowledge, this was the received classification. In the first kind no organic remains, as plants or shells, are found, and hence they were supposed to have been formed before the creation of organized beings. In the secondary, these remains exist, sometimes in great abundance. To this classification the celebrated Werner added the Transition class, which consists of the larger fragments of the primitive, and which is intermediate between this, and that usually called secondary.

At present, there are a considerable variety of classifications, some of which are too prolix and complicated for a popular work, while others are forbidding on account of the technical language in which they are written.