ments deposited in the deep bed of the ocean. Perhaps the foundation of some of our present coral islands, was begun in those remote ages, and that the successive architects of the solid pile, have reared a structure which has witnessed more than one revolution of the major axis of the earth's orbit. & We close with the following beautiful description of a coral grove, by Percival. "The floor is of sand, like the mountain-drift, And the pearl-shells 'spangle the flinty snow; Their boughs, where the tides and billows flow; For the winds and the waves are absent there; The sea-flag streams through the silent water, To blush like a banner bathed in slaughter; The fan-coral sweeps through the clear deep sea; Are bending like corn on the upland lea; Is sporting amid those bowers of stone, Where the myriad voices of ocean roar, Then far below in the peaceful sea The purple mullet and gold-fish rove, Where the waters murmur tranquilly Through the bending twigs of the coral-grove," ORGANIC REMAINS. 295 CHAPTER XII. Organic Remains. "And thou didst shine, thou rolling moon, upon As 'twere, anew, the gaps, of centuries." Byron. We have also IN. the preceding chapters we have, though somewhat imperfectly, given a sketch of the great causes of change now in operation on our globe, and we have shown that the earth's surface has been, and still is, subject to perpetual mutations. What was once dry land is now the bed of the ocean, and what is now the bed of the sea will one day be elevated land. seen that the crust or superficial covering of the globe is composed of strata succeeding each other in a well determined and regular order, and the remains of countless myriads of animals are entombed in them, which lived and died at periods long antecedent to the creation of the human race, nay, more than this, that almost every grain of sand and particle of dust wafted by the wind, teems with organized matter. We have lying before us specimens of whitish earth which to the unassisted eye appears but light chalky powder; we have but to wet a little of it and place it under the microscope and a thousand perfect forms are visible. From the midst of a lump of chalk we have extracted a nodule of flint, and by the hammer have chipped off several thin slices; one of these is now under the microscope by us, and we distinctly recognize two beautiful species of infusoria, as perfect and well defined as though now alive, and yet, these little beings have been entombed for myriads of years. What mighty changes have come over the face of our globe since the flinty sea encom. passed them, and how few of the countless thousands of all that sea, have been preserved for the curious gaze of the student of nature. The thoughts which overwhelm the mind when contemplating the wonders of the universe, impress us with almost a feeling of sadness that creation is so vast we can never comprehend the whole of it. The influence however, of scientific pursuits upon the mind, is most beneficial, and the great lesson taught by science is, that our habitual ideas, and our first impressions are far from being nearest the truth. Indeed we have already observed in the first part of this work, that Astronomy begins by convincing us that the sun, which apparently is revolving around the earth, is in reality still, but that our globe is turning daily on its axis, although apparently unmoving. Geology in like manner begins with even more unpleasant truths, and convinces us that the present configuration of the continents and seas, so far from being the primeval condition of things, is but one of the various vicissitudes through which the world has passed. We are accustomed to consider the earth as coeval with man, and that but five or six thousand years have elapsed since their creation. Geology demonstrates that our present abode is of far greater antiquity, and the slightest examination of the crust of the earth will convince us, that the substances of which it is composed, are the results of accumulations or deposits extended through a long period of cycles. As we have already observed all the strata, with the exceptions of the igneous rocks, the granite, the gneiss, and the mica-schist systems, are fossiliferous, and it is highly probable that even these rocks are of sedimentary origin, and once contained the remains of organic matter. The vast series of other deposits are the undoubted mineralized beds of primeval oceans, with occasional interpositions of lacrustine or lake formed, and fluviatile or river deposits, the former rivaling those of the vast Atlantic and Pacific, and the latter those of the immense inland lakes and rivers of the American continent. We do not find these mineralized beds or rocks, in all cases bearing the marks of quiet, but showing the agency of numerous disturbing influences, they have been upheaved and bent over; and broken through by the erupted and molten masses from beneath, MINERALS AND FOSSILS. 291 which have flown up through wide chasms and overspread them. Intervals of unusual volcanic agency, have been succeeded by ages of tranquil repose, and these again succeeded by a revival of former energy. We see in all these vast changes the control ing power of an Eternal Mind; periods of time which man in vain endeavors to comprehend, have witnessed continual exhibitions of creative power and wisdom. The diversified materials of which the earth is composed, have been elaborated into beauty and order, every object has its sphere of usefulness and action, and its period of existence is limited. We have never been able to perceive at all the grounds for the too hasty conclusion which some superficial philosophers have adopted, that the present perfect system of organization is the result of a progressive development of inferior types of existence, and that the remote origin of all life is the monad or animalcule. It has ever been the attempt of man to penetrate beyond the ordinary boundaries, which nevertheless, like the almost impassible barriers of a deep ocean surround him. Now with his heavendirected tube, he speculates upon the former conditions of all worlds. Penetrating back to periods of time far beyond the dream of the geologists, he imagines the wisps of nebulous matter which in a clear night, with the most powerful glasses, he can just descry, and which appear as rare and light as the thinnest vapor which floats in the form of a cloud on a summer's eve, these he imagines slowly condensing, and gradually forming worlds. The geologist looks back to the remote and primeval ages when the first life appeared on our planet, and he uncovers with careful hand the imbedded remains of fragile plants, and shells, which have lain hidden in their stony beds for periods of time compared with which, our years dwindle to utter insignificance. The whole substance of our globe, at least so far as the solid - materials which compose its crust are concerned, may be divided into two great classes, minerals and fossils. P MINERALS are inorganic snbstances, and are the products of chemical or electrical action. FOSSILS are the remains of organic substances imbedded in the . strata by natural causes at some remote period, and these remains are of the utmost importance in the eyes of geologists. If we examine the successive beds of water deposits in the various parts of our country we soon find that peculiar and characteristic fossils belonging to one locality. Or if we penetrate the earth to "such a depth that we reach the strata, which at some distan't place may crop out, or appear on the surface, as explained page 184, we will then find the same fossil remains as would be found at the surface at that distant place. The inference which we naturally draw from this is, that if at different ages of the globe, when the successive strata were deposited, different races of animals and vegetables flourished, then these fossil remains will enable us to determine with something like certainty, the relative ages of the strata which compose the various parts of a country, 'for it must be remembered that the mineralogical character of most of these beds is the same, and many times no opinion whatever can be formed from this. Hence these remains have been appropriately termed the "Medals of Creation," and they afford to the geologist precisely the same evidence of the character of the period when they existed, and were deposited, as an 'ancient coin to the numismatist, of the character of the people, "and the period when it was struck. Oftentimes a single coin or medal, is the sole remembrance which exists, to determine the date of a great event, and so a few bones, a shell, or a tooth, or track of a bird in the sand, are the sole memorials of peculiar types of existence of the primeval world. It would seem at first that from the very nature of the materials which compose most organic substances, that all traces of them would soon be obliterated. It is true that the soft and delicate parts of animal and vegetable organisms rapidly decay after death, yet in certain cases, their decomposition is arrested, and by a peculiar process every part is transformed into stone; thus, many of the most perishable vegetable tissues have been preserved, and even in the anthracite coal, which has been burned in the grate, distinct traces of organic structure can be observed under the microscope. The woody fibre of vegetables, the bones and teeth of animals, deeply imbedded in the earth, are thus preserved in some instances with wonderful accuracy and perfection. The perishable fleshy parts |