The Religion of Geology and Its Connected Sciences

by Edward Hitchcock

But I need not adduce any more advocates of the interpretation of Genesis, for which I contend. Men more respected and confided in by the Christian world I could not quote, though I might enlarge the number; but I trust it is unnecessary. I trust that all who hear me are satisfied that the Mosaic history of the creation of the world does fairly admit of an interpretation which leaves an undefined interval between the creation of matter and the six days’ work. Let it be recollected that I do not maintain that this is the most natural interpretation, but only that the passage will fairly admit it by the strict rules of exegesis. The question still remains to be considered, whether there is sufficient reason to adopt it as the true interpretation. To show that there is, I now make my appeal to geology. This is a case, it seems to me, in which we may call in the aid of science to ascertain the true meaning of Scripture. The question is, Does geology teach, distinctly and uncontrovertibly, that the world must have existed during a long period prior to the existence of the races of organized beings that now occupy its surface?

To give a popular view of the evidence sustaining the affirmative of this question is no easy task. It needs a full and accurate acquaintance with the multiplied facts of geology, and, what is still more rare, a familiarity with geological reasoning, in order to feel the full force of the arguments that prove the high antiquity of the globe. Yet I know that I have a right to presume upon a high degree of scientific knowledge, and an accurate acquaintance with geology, among those whom I address.

In the first place, I must recur to a principle already briefly stated in a former lecture, viz., that a careful examination of the rocks presents irresistible evidence, that, in their present condition, they are all the result of second causes; in other words, they are not now in the condition in which they were originally created. Some of them have been melted and reconsolidated, and crowded in between others, or spread over them. Others have been worn down into mud, sand, and gravel, by water and other agents, and again cemented together, after having enveloped multitudes of animals and plants, which are now imbedded as organic remains. In short, all known rocks appear to have been brought into their present state by chemical or mechanical agencies. It is indeed easy to say that these appearances are deceptive, and that these rocks may, with perfect ease, have been created just as we now find them. But it is not easy to retain this opinion, after having carefully examined them. For the evidence that they are of secondary origin is nearly as strong, and of the same kind too, as it is that the remains of edifices lately discovered in Central America are the work of man, and were not created in their present condition.

In the second place, processes are going on by which rocks are formed on a small scale, of the same character as those which constitute the great mass of the earth. Hence it is fair to infer, that all the rocks were formed in a similar manner. Beds of gravel, for instance, are sometimes cemented together by heat, or iron, or lime, so as to resemble exactly the conglomerates found in mountain masses among the ancient rocks. Clay is sometimes converted into slate by heat, as is soft marl into limestone, by the same cause. In fact, we find causes now in operation that produce all the varieties of known rocks, except some of the oldest, which seem to need only a greater intensity in some of the causes now at work to produce them. By ascertaining the rate at which rocks are now forming, therefore, we can form some opinion as to the time requisite to produce those constituting the crust of the globe. If, for instance, we can determine how fast ponds, lakes, and oceans are filling up with mud, sand, and gravel, conveyed to their bottoms, we can judge of the period necessary to produce those rocks which appear to have been formed in a similar manner; and if there is any evidence that the process was more rapid in early times, we can make due allowance.

In the third place, all the stratified rocks appear to have been formed out of the fragments of other rocks, worn down by the action of water and atmospheric agencies. This is particularly true of that large proportion of these rocks which contain the remains of animals and plants. The mud, sand, and gravel of which these are mostly composed, must have been worn from rocks previously existing, and have been transported into lakes, and the ocean, as the same process is now going on. There the animals and plants, which died in the waters, and were transported thither by rivers, must have been buried; next, the rocks must have been hardened into stone, by admixture with lime, or iron, or by internal heat; and, finally, have been raised above the waters, so as to become dry land. Beds of limestone are interstratified with those of shale, sandstone, and conglomerate; but these form only a small proportion of the whole, and, besides, were mostly formed in an analogous manner, though by agencies more decidedly chemical.

Now, for the most part, this process of forming rocks by the accumulation of mud, sand, and gravel is very slow. In general, such accumulations, at the bottom of lakes and the ocean, do not increase more than a few inches in a century. During violent floods, indeed, and in a few limited spots, the accumulation is much more rapid; as in the Lake of Geneva, through which the Rhone, loaded with detritus from the Alps, passes, where a delta has been formed two miles long and nine hundred feet thick, within eight hundred years.[7] And occasionally such rapid depositions probably took place while the older rocks were in the course of formation. But in general, the work seems to have gone on as slowly as it usually does at present.

Yet, in the fourth place, there must have been time enough since the creation to deposit at least ten miles of rocks in perpendicular thickness, in the manner that has been described. For the stratified rocks are at least of that thickness in Europe, and in this country much thicker; or, if we regard only the fossiliferous strata as thus deposited, (since some geologists might hesitate to admit that the non-fossiliferous rocks were thus produced,) these are six and a half miles thick in Europe, and still thicker in this country. How immense a period was requisite for such a work! Some do, indeed, contend that the work, in all cases, as we have allowed it in a few, may have been vastly more rapid than at the present day. But the manner in which the materials are arranged, and especially the preservation of the most delicate parts of the organic remains, often in the very position in which the animals died, show the quiet and slow manner in which the process went on.

In the fifth place, it is certain that, since man existed on the globe, materials for the production of rocks have not accumulated to the average thickness of more than one hundred or two hundred feet; although in particular places, as already mentioned, the accumulations are thicker. The evidence of this position is, that neither the works nor the remains of man have been found any deeper in the earth than in the upper part of that superficial deposit called alluvium. But had man existed while the other deposits were going on, no possible reason can be given why his bones and the fruits of his labors should not be found mixed with those of other animals, so abundant in the rocks, to the depth of six or seven miles. In the last six thousand years, then, only one five hundredth part of the stratified rocks has been accumulated. I mention this fact, not as by any means an exact, but only an approximate, measure of the time in which the older rocks were deposited; for the precise age of the world is probably a problem which science never can solve. All the means of comparison within our reach enable us to say, only, that its duration must have been immense.

In the sixth place, during the deposition of the stratified rocks, a great number of changes must have occurred in the matter of which they are composed. Hundreds of such changes can be easily counted, and they often imply great changes in the waters holding the materials in solution or suspension; such changes, indeed, as must have required different oceans over the same spot. Such events could not have taken place without extensive elevations and subsidences of the earth’s crust; nor could such vertical movements have happened without much intervening time, as many facts, too technical to be here detailed, show. Here, then, we have another evidence of vast periods of time occupied in the secondary production and arrangements of the earth’s crust.

In the seventh place, numerous races of animals and plants must have occupied the globe previous to those which now inhabit it, and have successively passed away, as catastrophes occurred, or the climate became unfit for their residence. Not less than thirty thousand species have already been dug out of the rocks; and excepting a few hundred species, mostly of sea shells, occurring in the uppermost rocks, none of them correspond to those now living on the globe. In Europe, they are found to the depth of about six and a half miles; and in this country, deeper; and no living species is found more than one twelfth of this depth. All the rest are specifically and often generically unlike living species; and the conclusion seems irresistible, that they must have lived and died before the creation of the present species. Indeed, so different was the climate in those early times,—it having been much warmer than at present in most parts of the world,—that but few of the present races could have lived then. Still further: it appears that, during the whole period since organized beings first appeared on the globe, not less than four, or five, and probably more—some think as many as ten or twelve—entire races have passed away, and been succeeded by recent ones; so that the globe has actually changed all its inhabitants half a dozen times. Yet each of the successive groups occupied it long enough to leave immense quantities of their remains, which sometimes constitute almost entire mountains. And in general, these groups became extinct in consequence of a change of climate; which, if imputed to any known cause, must have been an extremely slow process.