Lyell confesses that the test of organic remains must be used "under very much the same restrictions as the test of mineral composition." Sir Henry De la Beche, who variously illustrates this truth, gives, as one instance, the great incongruity there must be between the fossils of our carboniferous rocks and those of the marine strata deposited at the same period. But though, in the abstract, the danger of basing positive conclusions on evidence derived from fossils is clearly recognized, yet in the concrete this danger is generally disregarded. The established conclusions respecting the ages of strata, take but little note of it, and by some geologists it seems altogether ignored. Throughout his "Siluria," Sir Roderick Murchison habitually assumes that the same, or kindred species, lived in all parts of the earth at the same time.1 Having verified his assertion respecting Murchison, by instances selected from the work named, he convicts Lyell of the same error. "Notwithstanding facts like these," he says, "and notwithstanding his avowed opinion that the test of organic remains must be used 'under very much the same restrictions as the test of mineral composition,' Sir Charles Lyell, too, bases positive conclusions on this test, even where the community of fossils is slight and the distance great;" and cites marked cases in proof. 112 Huxley's testimony on the matter in hand is brief and to the point; and let us observe that it comes to us, not as the opinion of the author in 1862, but in 1870, when the revised addresses were put in book form. He says: If the further question be put whether physical geology is in possession of any method by which the actual synchrony (or the reverse), of any two distant deposits can be ascertained, no such method can be heard of: it being admitted by all the best authorities that neither similarity of mineral composition, nor of physical character, nor even direct continuity of stratum, are absolute proofs of the synchronism of even approximate sedimentary strata: while, for distant deposits, there seems to be no kind of physical evidence attainable of a nature competent to decide whether they possess any given difference of antiquity. All competent authorities will probably assent to the proposition that physical geology does not enable us in any way to reply to this question: Were the British cretaceous rocks deposited at the same time as those of India, or are they a million of years younger, or a million of years older ?3 He adds: "Is palæontology able to succeed where physical geology fails? Standard writers on paleontology, as has been seen, assume that she can. They take it for granted that deposits containing 1 Illustrations of Universal Progress, pp. 339, 340. 2 Ib., p. similar organic remains are synchronous, at any rate in a broad sense." He proceeds to show the untenable nature of the ground they occupy, and elsewhere asks, "Whether, after all, it might not be well for paleontologists to learn a little more carefully that scientific ars artium, the art of saying 'I don't know '?"2 Finally, Huxley makes this important declaration: For anything that geology or palaeontology are able to show to the contrary, a Devonian fauna and flora in the British Islands may have been contemporaneous with Silurian life in North America, and with a Carboniferous fauna and flora in Africa. It may be so; it may be otherwise. In the present condition of our knowledge, and of our methods one verdict, "not proven and not provable,"-must be recorded against all the grand hypotheses of the paleontologist respecting the general succession of life on the globe. The order and nature of terrestial life as a whole, are open questions. Geology, at present, provides us with most valuable topographical records, but she has not the means of working them into a universal history.3 Accepting these passages from Spencer and Huxley as statements. of most important truths, we wish, at the same time, to be fully understood as having no sympathy with the use which they make of them in the interests of their pet and pernicious philosophy of evolution in general, and of the Darwinian theory in particular. And we may properly claim that the foregoing testimony of both writers is not less, but rather the more valuable for our purpose, because it was given on the opposite side of the theological question than that for which we employ it. But as already intimated, the revelations of the dredge only began with Edward Forbes. His observations in the Ægean led him to suppose that the zero of animal life would be found at a depth of about 300 fathoms. Within a few years past, as is well known, the British and Swedish governments, and our own, have provided for dredgings at great depths, too expensive to be undertaken at the charge of individual naturalists. The English dredgers have reached, in lat. 47° 38′ north, and long. 12° 08′ west from Greenwich, a depth of 2435 fathoms, and found, even there, living in no small numbers, large and highly organized animals. Deep-sea dredgings in the gulf stream have brought up a great variety of animals in a profusion rivalling that of shoal waters. It is practically proved that depth sets no limit to animal life; that many genera and species 1 Lay Sermons, Addresses, and Reviews, p. 210. 2 Ib., p. 206. 3 Ib., p. 213. hitherto regarded as extinct and peculiar to ancient epochs, still survive; that cold and warm areas may co-exist close together, side by side, one tenanted by boreal, and another by temperate or tropical species. It is hardly necessary to observe that such facts contradict current geological theories, and afford additional proof of the inadequacy of their foundations. In Prof. Agassiz's report on the dredgings in the Gulf Stream, dated November, 1869, and to be found printed in the "Bulletin of the Museum of Comparative Zoölogy," occurs a passage of remarkable significance. It is this: There is one subject of scientific research, the connection of which with deep-sea soundings cannot fail to lead to unexpected results. From what I have seen of the deep-sea bottom, I am already led to infer that among the rocks forming the bulk of the stratified crust of our globe, from the oldest to the youngest formation, there are probably none which have been formed in very deep waters. If this be so, we shall have to admit that the areas now respectively occupied by our continents, as circumscribed by the 200 fathom curve or thereabout, and the oceans at greater depth, have from the beginning [mark the words from the beginning] retained their relative outline and position; the continents having been at all times areas of gradual upheaval, with comparatively slight oscillations of rise and subsidence, and the oceans at all times areas of gradual depression with equally slight oscillations. Now that the geological constitution of our continent is satisfactorily known over the greater part of its extent, it seems to me to afford the strongest evidence that this has been the case; while there is no support whatever for the assumption that any part of it has sunk again to any very great depth after its rise above the surface of the ocean. The fact that upon the American continent, east of the Rocky Mountains, the geological formations crop out, in their regular succession, from the oldest azoic and primordial deposits to the cretaceous formation, without the slightest indication of a great subsidence, seems to me the most complete and direct demonstration of my proposition. Moreover, the position of the cretaceous and tertiary formations, along the low grounds east of the Alleghany range, is another indication of the permanence of the ocean trough, on the margin of which these more recent beds have been formed. I am well aware that in a comparatively recent period, portions of Canada and the United States, which now stand six or seven hundred feet above the level of the sea, have been under water; but this has not changed the configuration of the continent, if we admit that the latter is in reality circumscribed by the 200 fathom curve of depth. Here we have, on the part of a distinguished leader in science, an 1 Vol. I, No. 13, pp. 368, 369. undisguised abandonment of the accepted and leading doctrine that continental and oceanic areas are not permanent, but interchangeable. Yet the latest standard publications of geological theories, as now held,—the last editions of Lyell's "Principles," and of his "Elements," the latter not yet three months from the press,-recognize throughout this doctrine and its vast requirements of time. A single sentence from the "Elements" is conclusive in this respect; it is as follows: "We need not be surprised if we learn from geology that the continents and oceans were not always placed where they now are, although the imagination may well be overpowered when it endeavors to contemplate the quantity of time required for such revolutions." In view of the foregoing testimony, how shall we avoid the conclusion that several of the current leading theories of geology are hasty generalizations from insufficient data? And if so, it must follow that the old classifications and names to which they have given rise, serve at present to hamper rather than promote the advance of the science. If geology has not outgrown its theories, how is it that, as we have seen, the most cautious geologists are unable to write upon the questions and phenomena with which they are concerned, without falling into inconsistency? Is it not true that the old nomenclature of periods and systems necessarily keeps alive the original implications, and does not the need of arranging new data in some order, naturally result in their being thrust into classifications whose incongruity with the data is very glaring? And what hinders the casting off of outgrown theories but the tenacity of old associations, and unwillingness to confess with Huxley that a scheme that shall be of universal application is now impossible? Of Agassiz's recent view,' the logical results have not been publicly remarked, so far as we are aware. It is quite impossible, in the present aspect of theories, to conjecture how a rational system of geology can be built up, unless the old idea of the alternation of continental and oceanic areas be abandoned. But this involves a revolution on a grand scale. Agassiz's supposition that "the continents have at all times been areas of gradual upheaval, with comparatively slight oscillations of rise and subsidence, and the oceans at all times areas of gradual depression, with equally slight oscillations," furnishes, it would seem, a promising basis for a new geology. If we start with such a doctrine, the acknowledged simplicity and unity of North American geology is readily accounted for, as Agassiz has shown. 1 The idea of the permanence of oceanic and continental areas was first advanced by Professor Dana (Manual of Geology, 1863); but the doctrine was first fully stated by Agassiz. But in such a scheme each continent must have its own history, for nearly connected as are the eastern and western continents upon the north (nearly enough to account for migrations of species through both from single specific centres of creation), and connected as is South with North America by an isthmus, yet lying between more eastern meridians, neither geological nor palæontological evidence, as we have already seen, can ever be expected to prove synchronism in the movements of their wholes or parts. Each new continent, if not subjected to very great disturbance in the general process of its upheaval, would exhibit, as North America does, "the geological formations cropping out in their regular succession, from the oldest azoic and primordial deposits" to the latest, with clear evidence of the successive introduction of higher types of life to correspond to higher and higher conditions of the earth. Such a progress nothing heretofore said has, on our part, been intended to deny. And this is in strict accordance with what Agassiz maintains in his "Geological Sketches," in these words: "For thirty years geology has been gradually establishing by evidence, the fulness and accuracy of which are truly amazing, the regularity in the sequence of the geological formations." The geological history of each continent would be best expressed in terms and classifications of its own. Should this new view be substantiated, its consequences would not stop with the limits of geology. It would at one stroke sweep away the foundation of the Darwinian theory and of the whole doctrine of evolution as now held, so essential to the purposes of materialism; for it points to the actual beginning of life as coeval with the earliest existing fossiliferous rocks, establishes the approximate completeness of the geological record, and the gratuitous nature of the assumption that untold millions of years are necessary to account for the facts of geology and palæontology. The advocates of the hypothesis of natural selection admit it to be wholly untenable unless the geological record is acknowledged to be a mere fragment,-the last chapter of the earth's history, and geological time to be practically illimitable. Huxley concedes all this in a single paragraph. He says: 2 Obviously, if the earliest fossiliferous rocks now known are coeval with the commencement of life, and if their contents give us any just conception of the nature and the extent of the earliest fauna and flora, the insignificant amount of modification which can be demonstrated to have taken place in any one group of animals or plants, is quite incompatible 1 P. 207. Op. cit., p. 226. |