The Testimony of the Rocks Part 8

ASAPHUS CAUDATUS.

(_Silurian._)]

[Ill.u.s.tration: Fig. 78.

ORTHOCERAS LATERALE.

(_Mountain Limestone._)]

[Ill.u.s.tration: Fig. 79.

SPIRIGERINA RETICULARIS.

(_Old Red Sandstone._)]

[Ill.u.s.tration: Fig. 80.

A. MARGARITATUS.

(_Lias._)]

[Ill.u.s.tration: Fig. 81.

A. BISULCATUS.

(_Lias._)]

[Ill.u.s.tration: Fig. 82.

BELEMNITELLA MUCRONATA.

(_Chalk._)]

[Ill.u.s.tration: Fig. 83.

BELEMNITES SULCATUS.

(_Oolite._)]

In the limits to which I have restricted myself, I have been able to do little more than simply to chronicle the successive eras in which the various cla.s.ses and divisions of the organic kingdom, vegetable and animal, make their appearance in creation. I have produced merely a brief record of the various births, in their order, of that great family whose father is G.o.d. And in pursuing such a plan, much, of necessity, must have been omitted. I ought perhaps to have told you, that very rarely, if ever, do the master forms of a period const.i.tute the prevailing or typical organisms of its deposits. Of the three great divisions of which the geologic scale consists,--Palaeozoic, Secondary, and Tertiary,--the first, or ichthyic period, is marked chiefly, not by its great fishes, but by the peculiar character of its brachipodous and cephalopodous mollusca, and in its earlier stages by its three-lobed crustaceae; the second or reptilian period was emphatically the period of the ammonite and belemnite; while the third and last, or mammalian period, was that of gastropodous and conchiferous molluscs, impressed, generically at least, by all the features of the group which still exists in our seas. Save in a few local deposits, fishes do not form the prevailing organisms in the formations of the age of fishes; nor reptiles in the formations of the age of reptiles; nor yet mammals in the formations of the age of mammals. Nay, it is not improbable that the recent or human period may be marked most prominently in the future, when it comes to exist simply as a geologic system, by a still humbler organism than most of these molluscs. On almost all rocky sh.o.r.es a line of pale gray may be seen at low water, running for mile after mile along the belt that has been laid bare at the bases of the cliffs by the fall of the tide. It owes its pale color to millions of millions of a small bala.n.u.s (_B. balanoides_), produced in such amazing abundance in the littoral zone as to cover with a rough crust every minute portion of rock and every sedentary sh.e.l.l. Other species of the same genus (_B.

crenatus_ and _B. porcatus_) occupy the depths of the sea beyond; and their remains, washed ash.o.r.e by the waves, and mingled with those of the littoral species, form often great acc.u.mulations of sh.e.l.l sand. I have seen among the Hebrides a sh.e.l.l sand acc.u.mulated along the beach to the depth of many feet, of which fully two thirds was composed of the valves and compartments of balanidae; and a similar sand on the east coast of Scotland, a little to the south of St. Andrews, formed in still larger proportions of the fragments of a single species,--_Bala.n.u.s crenatus_.

Now, this genus, so amazingly abundant at the present time in every existing sea, and whose acc.u.mulated remains bid fair to exist as great limestone rocks in the future, had no existence in the Palaeozoic or Secondary ages. It first appears in the times of the earlier Tertiary, in, however, only a single species; and, becoming gradually of more and more importance as a group, it receives its fullest numerical development in the present time. And thus the remains of a sub-cla.s.s of animals, low in their standing among the articulata, may form one of the most prominent Palaeontological features of the human period. But enough for the present of circ.u.mstance and detail.

[Ill.u.s.tration: Fig. 84.

MUREX ALVEOLATUS.

(_Red Crag._)]

[Ill.u.s.tration: Fig. 85.

ASTARTE OMALII.

(_Red Crag._)]

[Ill.u.s.tration: Fig. 86.

BALa.n.u.s CRa.s.sUS.

(_Red Crag._)]

Such, so far as the geologist has yet been able to read the records of his science, has been the course of creation, from the first beginnings of vitality upon our planet, until the appearance of man. And very wonderful, surely, has that course been! How strange a procession! Never yet on Egyptian obelisk or a.s.syrian frieze,--where long lines of figures seem stalking across the granite, each charged with symbol and mystery,--have our Layards or Rawlinsons seen aught so extraordinary as that long procession of being which, starting out of the blank depths of the bygone eternity, is still defiling across the stage, and of which we ourselves form some of the pa.s.sing figures. Who shall declare the profound meanings with which these geologic hieroglyphics are charged, or indicate the ultimate goal at which the long procession is destined to arrive?

The readings already given, the conclusions already deduced, are as various as the hopes and fears, the habits of thought, and the cast of intellect, of the several interpreters who have set themselves,--some, alas! with but little preparation and very imperfect knowledge,--to declare in their order the details of this marvellous, dream-like vision, and, with the dream, "the interpretation thereof." One cla.s.s of interpreters may well remind us of the dim-eyed old man,--the genius of unbelief so poetically described by Coleridge,--who, sitting in his cold and dreary cave, "talked much and vehemently concerning an infinite series of causes and effects, which he explained to be a string of blind men, the last of whom caught hold of the skirt of the one before him, he of the next, and so on, till they were all out of sight, and that they all walked infallibly straight, without making one false step, though all were alike blind." With these must I cla.s.s those a.s.sertors of the development hypothesis who can see in the upward progress of being only the operations of an incomprehending and incomprehensible law, through which, in the course of unreckoned ages, the lower tribes and families have risen into the higher, and inferior into superior natures, and in virtue of which, in short, the animal creation has grown, in at least its n.o.bler specimens, altogether unwittingly, without thought or care on its own part, and without intelligence on the part of the operating law, from irrational to rational, and risen in the scale from the mere promptings of instinct to the highest exercise of reason,--from apes and baboons to Bacons and Newtons. The blind lead the blind;--the unseeing law operates on the unperceiving creatures; and they go, not together into the ditch, but direct onwards, straight as an arrow, and higher and higher at every step.

Another cla.s.s look with profound melancholy on that great city of the dead,--the burial-place of all that ever lived in the past,--which occupies with its ever-extending pavements of gravestones, and its ever-lengthening streets of tombs and sepulchres, every region opened up by the geologist. They see the onward procession of being as if but tipped with life, and nought but inanimate carca.s.ses all behind,--dead individuals, dead species, dead genera, dead creations,--a universe of death; and ask whether the same annihilation which overtook in turn all the races of all the past, shall not one day overtake our own race also, and a time come when men and their works shall have no existence save as stone-pervaded fossils locked up in the rock forever? Nowhere do we find the doubts and fears of this cla.s.s more admirably portrayed than in the works of perhaps the most thoughtful and suggestive of living poets:--

"Are G.o.d and Nature then at strife, That Nature lends such evil dreams, So careful of the type she seems, So careless of the single life?

'So careful of the type!' but no, From scarped cliff and quarried stone, She cries, 'A thousand types are gone; I care for nothing; all shall go: Thou makest thine appeal to me; I bring to life, I bring to death; The spirit does but mean the breath.

I know no more.' And he,--shall he, Man, her last work, who seemed so fair, Such splendid purpose in his eyes, Who rolled the psalm to wintry skies And built him fanes of fruitless prayer, Who trusted G.o.d was love indeed, And love creation's final law, Though Nature, red in tooth and claw, With ravine shrieked against his creed,-- Who loved, who suffered countless ills, Who battled for the true, the just,-- Be blown about the desert dust, Or sealed within the iron hills?

No more!--a monster then, a dream, A discord. Dragons of the prime, That tore each other in their slime, Were mellow music matched with him.

O, life, as futile then as frail,-- O for thy voice to soothe and bless!

What hope of answer or redress, Behind the vail, behind the vail!"

The sagacity of the poet here,--that strange sagacity which seems so nearly akin to the prophetic spirit,--suggests in this n.o.ble pa.s.sage the true reading of the enigma. The appearance of man upon the scene of being const.i.tutes a new era in creation; the operations of a new _instinct_ come into play,--that _instinct_ which antic.i.p.ates a life after the grave, and reposes in implicit faith upon a G.o.d alike just and good, who is the pledged "rewarder of all who diligently seek Him." And in looking along the long line of being,--ever rising in the scale from higher to yet higher manifestations, or abroad on the lower animals, whom instinct never deceives,--can we hold that man, immeasurably higher in his place, and infinitely higher in his hopes and aspirations, than all that ever went before him, should be, notwithstanding, the one grand error in creation,--the one painful worker, in the midst of present trouble, for a state into which he is never to enter,--the befooled expectant of a happy future, which he is never to see? a.s.suredly no. He who keeps faith with all his humbler creatures,--who gives to even the bee and the dormouse the winter for which they prepare,--will to a certainty not break faith with man,--with man, alike the deputed lord of the present creation, and the chosen heir of all the future. We have been looking abroad on the old geologic burying-grounds, and deciphering the strange inscriptions on their tombs; but there are other burying-grounds, and other tombs,--solitary churchyards among the hills, where the dust of the martyrs lies, and tombs that rise over the ashes of the wise and good; nor are there awanting, on even the monuments of the perished races, frequent hieroglyphics, and symbols of high meaning, which darkly intimate to us, that while _their_ burial-yards contain but the debris of the past, we are to regard the others as charged with the sown seed of the future.

LECTURE THIRD.

THE TWO RECORDS, MOSAIC AND GEOLOGICAL.

It is now exactly fifty years since a clergyman of the Scottish Church, engaged in lecturing at St. Andrews, took occasion in enumerating the various earths of the chemist, to allude to the science, then in its infancy, that specially deals with the rocks and soils which these earths compose. "There is a prejudice," he remarked, "against the speculations of the geologist, which I am anxious to remove. It has been said that they nurture infidel propensities. It has been alleged that geology, by referring the origin of the globe to a higher antiquity than is a.s.signed to it by the writings of Moses, undermines our faith in the inspiration of the Bible, and in all the animating prospects of the immortality which it unfolds. This is a false alarm. _The writings of Moses do not fix the antiquity of the globe._"

The bold lecturer on this occasion,--for it needed no small courage in a divine of any Established Church to take up, at the beginning of the present century, a position so determined on the geologic side,--was at the time an obscure young man, characterized, in the small circle in which he moved, by the ardor of his temperament and the breadth and originality of his views; but not yet distinguished in the science or literature of his country, and of comparatively little weight in the theological field. He was marked, too, by what his soberer acquaintance deemed eccentricities of thought and conduct. When the opposite view was all but universal, he held and taught that free trade would be not only a general benefit to the people of this country, but would inflict permanent injury on no one cla.s.s or portion of them; and further, at a time when the streets and lanes of all the great cities of the empire were lighted with oil burnt in lamps, he held that the time was not distant when a carburetted hydrogen gas would be subst.i.tuted instead; and, on getting his snug parsonage-house repaired, he actually introduced into the walls a system of tubes and pipes for the pa.s.sage into its various rooms of the gaseous fluid yet to be employed as the illuminating agent. Time and experience have since impressed their stamp on these supposed eccentricities, and shown them to be the sagacious forecastings of a man who saw further and more clearly than his contemporaries; and fame has since blown his name very widely, as one of the most comprehensive and enlightened, and, withal, one of the most thoroughly earnest and sincere, of modern theologians. The bold lecturer of St. Andrews was Dr. Thomas Chalmers,--a divine whose writings are now known wherever the English language is spoken, and whose wonderful eloquence lives in memory as a vanished power, which even his extraordinary writings fail adequately to represent. And in the position which he took up at this early period with respect to geology and the Divine Record, we have yet another instance of the great sagacity of the man, and of his ability of correctly estimating the prevailing weight of the evidence with which, though but partially collected at the time, the geologist was preparing to establish the leading propositions of his science. Even in this late age, when the scientific standing of geology is all but universally recognized, and the vast periods of time which it demands fully conceded, neither geologist nor theologian, could, in any new scheme of reconciliation, shape his first proposition more skilfully than it was shaped by Chalmers a full half century ago. It has formed since that time the preliminary proposition of those ornaments of at once science and the English Church, the present venerable Archbishop of Canterbury, Dr. Bird Sumner, with Doctors Buckland, Conybeare, and Professor Sedgwick; of eminent evangelistic Dissenters too, such as the late Dr. Pye Smith, Dr. John Harris, Dr. Robert Vaughan, Dr. James Hamilton, and the Rev. Mr. Binney,--enlightened and distinguished men, who all came early to the conclusion, with the lecturer of St. Andrews, that "the writings of Moses do not fix the antiquity of the globe."

In 1814, ten years after the date of the St. Andrews' lectures, Dr.

Chalmers produced his more elaborate scheme of reconciliation between the Divine and the Geologic Records, in a "Review of Cuvier's Theory of the Earth;" and that scheme, perfectly adequate to bring the Mosaic narrative into harmony with what was known at the time of geologic history, has been very extensively received and adopted. It may, indeed, still be regarded as the most popular of the various existing schemes.

It teaches, and teaches truly, that between the first act of creation, which evoked out of the previous nothing the _matter_ of the heavens and earth, and the first act of the first day's work recorded in Genesis, periods of vast duration may have intervened; but further, it insists that the days themselves were but natural days of twenty-four hours each; and that, ere they began, the earth, though mayhap in the previous period a fair residence of life, had become void and formless, and the sun, moon, and stars, though mayhap they had before given light, had been, at least in relation to our planet, temporarily extinguished. In short, while it teaches that the successive creations of the geologist may all have found ample room in the period preceding that creation to which man belongs, it teaches also that the record in Genesis bears reference to but the existing creation, and that there lay between it and the preceding ones a chaotic period of death and darkness. The scheme propounded by the late Dr. Pye Smith, and since adopted by several writers, differs from that of Chalmers in but one circ.u.mstance, though an important one. Dr. Smith held, with the great northern divine, that the Mosaic days were natural days; that they were preceded by a chaotic period; and that the work done in them related to but that last of the creations to which the human species belongs. Further, however, he held in addition, that the chaos of darkness and confusion out of which that creation was called was of but limited extent, and that outside its area, and during the period of its existence, many of our present lands and seas may have enjoyed the light of the sun, and been tenanted by animals and occupied by plants, the descendants of which still continue to exist. The treatise of Dr. Pye Smith was published exactly a quarter of a century posterior to the promulgation, through the press, of the argument of Dr. Chalmers; and this important addition,--elaborated by its author between the years 1837 and 1839,--seems to have been made to suit the more advanced state of geological science at the time. The scheme of reconciliation perfectly adequate in 1814 was found in 1839 to be no longer so; and this mainly through a peculiarity in the order in which geological fact has been evolved and acc.u.mulated in this country, and the great fossiliferous systems studied and wrought out; to which I must be permitted briefly to advert.

William Smith, the "Father of English Geology," as he has been well termed (a humble engineer and mineral surveyor, possessed of but the ordinary education of men of his cla.s.s and profession), was born upon the English Oolite,--that system which, among the five prevailing divisions of the great Secondary cla.s.s of rocks, holds exactly the middle place. The Tria.s.sic system and the Lias lie beneath it; the Cretaceous system and the Weald rest above. Smith, while yet a child, had his attention attracted by the Oolitic fossils; and it was observed, that while his youthful contemporaries had their garnered stores of marbles purchased at the toy shop, he had collected, instead, a h.o.a.rd of spherical fossil terebratulae, which served the purposes of the game equally well. The interest which he took in organic remains, and the deposits in which they occur, influenced him in the choice of a profession; and, when supporting himself in honest independence as a skilful mineral surveyor and engineer, he travelled over many thousand miles of country, taking as his starting point the city of Bath, which stands near what is termed the Great Oolite: and from that centre he carefully explored the various Secondary formations above and below. He ascertained that these always occur in a certain determinate order; that each contains fossils peculiar to itself; and that they run diagonally across the kingdom in nearly parallel lines from north-east to south-west. And, devoting every hour which he could s.n.a.t.c.h from his professional labors to the work, in about a quarter of a century, or rather more, he completed his great stratigraphical map of England. But, though a truly Herculean achievement, regarded as that of a single man unindebted to public support, and uncheered by even any very general sympathy in his labors, it was found to be chiefly valuable in its tracings of the Secondary deposits, and strictly exact in only that Oolitic centre from which his labors began. It was remarked at an early period that he ought to have restricted his publication to the formations which lie between the Chalk and the Red Marl inclusive; or, in other words, to the great Secondary division. The Coal Measures had, however, been previously better known, from their economic importance, and the number of the workings opened among them, than the deposits of any other system; and ere the publication of the map of Smith, Cuvier and Brogniart had rendered famous all over the world the older Tertiary formations of the age of the London Clay. But both ends of the geological scale, comprising those ancient systems older than the Coal, and representative of periods in which, so far as is yet known, life, animal and vegetable, first began upon our planet, and those systems of comparatively modern date, representative of the periods which immediately preceded the human epoch, were equally unknown. The light fell strongly on only that middle portion of the series on which the labors of Smith had been mainly concentrated. The vast geologic bridge, which, like that in the exquisite allegory of Addison, strode across a "part of the great tide of eternity," "had a black cloud hanging at each end of it." And such was the state of geologic science when, in 1814, Dr. Chalmers framed his scheme of reconciliation.

Since that time, however, a light not less strong than the one thrown by William Smith on the formations of the Lias and the Oolite has been cast on both the older and the newer fossiliferous systems. Two great gaps still remain to be filled up,--that which separates the Palaeozoic from the Secondary division, and that which separates the Secondary from the Tertiary one. But they occur at neither end of the geological scale.

Mainly through the labors of two distinguished geologists, who, finding the geologic school of their own country distracted by a fierce and fruitless controversy, attached themselves to the geologic school of England, and have since received the honor of knighthood in acknowledgment of their labors, both ends of the geologic scale have been completed. Sir Roderick Murchison addressed himself to the formations older than the Coal, more especially to the Upper and Lower Silurian systems, from the Ludlow rooks to the Llandeilo flags. The Old Red Sandstone too, a system which lies more immediately beneath the Coal, has also been explored, and its various deposits, with their peculiar organic remains, enumerated and described. And Sir Charles Lyell, setting himself to the other extremity of the scale, has wrought out the Tertiary formations, and separated them into the four great divisions which they are now recognized as forming. And of these, the very names indicate that certain proportions of their organisms still continue to exist. It is a great fact, now fully established in the course of geological discovery, that between the plants which in the present time cover the earth, and the animals which inhabit it, and the animals and plants of the later extinct creations, there occurred no break or blank, but that, on the contrary, many of the existing organisms were contemporary during the morning of their being, with many of the extinct ones during the evening of theirs. We know further, that not a few of the sh.e.l.ls which now live on our coasts, and several of even the wild animals which continue to survive amid our tracts of hill and forest, were in existence many ages ere the human age began. Instead of dating their beginning only a single natural day, or at most two natural days, in advance of man, they must have preceded him by many thousands of years. In fine, in consequence of that comparatively recent extension of geologic fact in the direction of the later systems and formations, through which we are led to know that the present creation was not cut off abruptly from the preceding one, but that, on the contrary, it dovetailed into it at a thousand different points, we are led also to know, that any scheme of reconciliation which would separate between the recent and the extinct existences by a chaotic gulf of death and darkness, is a scheme which no longer meets the necessities of the case. Though perfectly adequate forty years ago, it has been greatly outgrown by the progress of geological discovery, and is, as I have said, adequate no longer; and it becomes a not unimportant matter to determine the special scheme that would bring into completest harmony the course of creation, as now ascertained by the geologist, and that brief but sublime narrative of its progress which forms a meet introduction in Holy Writ to the history of the human family. The first question to which we must address ourselves in any such inquiry is of course a very obvious one,--_What are the facts scientifically determined which now demand a new scheme of reconciliation?_

There runs around the sh.o.r.es of Great Britain and Ireland a flat terrace of unequal breadth, backed by an escarpment of varied height and character, which is known to geologists as the old coast-line. On this flat terrace most of the seaport towns of the empire are built. The subsoil which underlies its covering of vegetable mould consists usually of stratified sands and gravels, arranged after the same fas.h.i.+on as on the neighboring beach, and interspersed in the same manner with sea sh.e.l.ls. The escarpment behind, when formed of materials of no great coherency, such as gravel or clay, exists as a sloping, gra.s.s-covered bank,--at one place running out into promontories that encroach upon the terrace beneath,--at another receding into picturesque, bay-like recesses; and where composed, as in many localities, of rock of an enduring quality, we find it worn, as if by the action of the surf,--in some parts relieved into insulated stacks, in others hollowed into deep caverns,--in short, presenting all the appearance of a precipitous coast-line, subjected to the action of the waves. Now, no geologist can or does doubt that this escarpment was at one time the coast-line of the island,--the line against which the waves broke at high water in some distant age, when either the sea stood from twenty to thirty feet higher along our sh.o.r.es than it does now, or the land sat from twenty to thirty feet lower. Nor can the geologist doubt, that along the flat terrace beneath, with its stratified beds of sand and gravel, and its acc.u.mulations of sea sh.e.l.ls, the tides must have risen and fallen twice every day, as they now rise and fall along the beach that at present girdles our country. But, in reference to at least human history, the age of the old coast-line and terrace must be a very remote one. Though geologically recent, it lies far beyond the reach of any written record.

It has been shown by Mr. Smith of Jordanhill, one of our highest authorities on the subject, that the wall of Antoninus, erected by the Romans as a protection against the Northern Caledonians, was made to terminate at the Firths of Forth and Clyde, with relation, not to the level of the old coast-line, but to that of the existing one. And so we must infer that, ere the year A.D. 140 (the year during which, according to our antiquaries, the greater part of the wall was erected) the old coast-line had attained to its present elevation over the sea. Further, however, we know from the history of Diodorus the Sicilian, that at a period earlier by at least two hundred years, St. Michael's Mount, in Cornwall, was connected with the mainland at low water, just as it is now, by a flat isthmus, across which, upon the falling of the tide, the ancient Cornish miners used to carry over their tin in carts. Had the relative levels of sea and land been those of the old coast-line at the time, St. Michael's Mount, instead of being accessible at low ebb would have been separated from the sh.o.r.e by a strait from three to five fathoms in depth. It would not have been then as now, as described in the verse of Carew,--