HUGH MILLER
Hugh Miller was born in Cromarty, in the North of Scotland, October 10, 1802. From the time he was seventeen until he was thirty-four, he worked as a common stone-mason, although devoting his leisure hours to independent researches in natural history, for which he formed a taste early in life. He became interested in journalism, and was editor of the Edinburgh "Witness," when, in 1840, he published the contents of the volume issued a year later as "The Old Red Sandstone." The book deals with its author's most distinctive work, namely, finding fossils that tell much of the history of the Lower Old Red Sandstone, and fixing in the geological scale the place to which the larger beds of remains found in the system belong. Besides being a practical and original geologist, Miller had a fine imaginative power, which enabled him to reconstruct the past from its ruinous relics. The fact that he unfortunately set himself the task of combating the theory of evolution, which was fast gaining ground in his day, should not blind us to the high value of his geological experiences. The results of his observations provide some of the most cogent proofs of the theory he disputed. Late in life Miller's mind gave way, and he put an end to his own life on December 24, 1856.
I.—A Stone-mason's Researches
My advice to young working men desirous of bettering their circumstances, and adding to the amount of their enjoyment, is to seek happiness in study. Learn to make a right use of your eyes; the commonest things are worth looking at—even stones, weeds, and the most familiar animals. There are none of the intellectual or moral faculties, the exercise of which does not lead to enjoyment; hence it is that happiness bears so little reference to station.
Twenty years ago I made my first acquaintance with a life of labour and restraint. I was but a slim, loose-jointed boy at the time, fond of the pretty intangibilities of romance, and of dreaming when broad awake; and, woful change! I was now going to work in a quarry. I was going to exchange all my day-dreams for the kind of life in which men toil every day that they may be enabled to eat, and eat every day that they may be enabled to toil!
That first day was no very formidable beginning of the course of life I had so much dreaded. To be sure, my hands were a little sore, and I felt nearly as much fatigued as if I had been climbing among the rocks; but I had wrought and been useful, and had yet enjoyed the day fully as much as usual. I was as light of heart next morning as any of my brother-workmen. That night, arising out of my employment, I found I had food enough for thought without once thinking of the unhappiness of a life of labour.
In the course of the day I picked up a nodular mass of blue limestone, and laid it open by a stroke of the hammer. Wonderful to relate, it contained inside a beautifully finished piece of sculpture, one of the volutes, apparently, of an Ionic capital. Was there another such curiosity in the whole world? I broke open a few other nodules of similar appearance, and found that there might be. In one of these there were what seemed to be scales of fishes and the impressions of a few minute bivalves, prettily striated; in the centre of another there was actually a piece of decayed wood.
Of all nature's riddles these seemed to me to be at once the most interesting and the most difficult to expound. I treasured them carefully up, and was told by one of the workmen to whom I showed them that there was a part of the shore, about two miles further to the west, where curiously shaped stones, somewhat like the heads of boarding-pikes, were occasionally picked up, and that in his father's day the country people called them thunderbolts. Our first half-holiday I employed in visiting the place where the thunderbolts had fallen so thickly, and found it a richer scene of wonder than I could have fancied even in my dreams.
My first year of labour came to a close, and I found that the amount of my happiness had not been less than in the last of my boyhood. My knowledge had increased in more than the ratio of former seasons; and as I had acquired the skill of at least the common mechanic, I had fitted myself for independence.
My curiosity, once fully awakened, remained awake, and my opportunities of gratifying it have been tolerably ample. I have been an explorer of caves and ravines, a loiterer along sea-shores, a climber among rocks, a labourer in quarries. My profession was a wandering one. I remember passing direct, on one occasion, from the wild western coast of Ross-shire, where the Old Red Sandstone leans at a high angle against the prevailing quartz of the district, to where, on the southern skirts of Midlothian, the Mountain Limestone rises amid the coal. I have resided one season on a raised beach of the Moray Firth. I have spent the season immediately following amid the ancient granite and contorted schists of the central Highlands. In the north I have laid open by thousands the shells and lignites of the oolite; in the south I have disinterred from their matrices of stone or of shale the huge reds and tree ferns of the carboniferous period.
I advise the stone-mason to acquaint himself with geology. Much of his time must be spent amid the rocks and quarries of widely separated localities, and so, in the course of a few years he may pass over the whole geological scale, and this, too, with opportunities of observation at every stage which can be shared with him by only the gentleman of fortune who devotes his whole time to study. Nay, in some respects, his advantages are superior to those of the amateur, for the man whose employments have to be carried on in the same formation for months, perhaps years, enjoys better opportunities of arriving at just conclusions. There are formations which yield their organisms slowly to the discoverer, and the proofs which establish their place in the geological scale more tardily still. I was acquainted with the Old Red Sandstone of Ross and Cromarty for nearly ten years ere I ascertained that it is richly fossiliferous; I was acquainted with it for nearly ten years more ere I could assign its fossils to their exact place in the scale. Nature is vast and knowledge limited, and no individual need despair of adding to the general fund.
II.—Bridging Life's Gaps
"The Old Red Sandstone," says a Scottish geologist in a digest of some recent geological discoveries, "has hitherto been considered as remarkably barren of fossils." Only a few years have gone by since men of no low standing in the science disputed the very existence of this formation—or system, rather, for it contains at least three distinct formations. There are some of our British geologists who still regard it as a sort of debatable tract, entitled to no independent status, a sort of common which should be divided.
It will be found, however, that this hitherto neglected system yields in importance to none of the others, whether we take into account its amazing depth, the great extent to which it is developed both at home and abroad, the interesting links which it furnishes in the geological scale, or the vast period of time which it represents. There are localities in which the depth of the Old Red Sandstone fully equals the elevation of Mount Etna over the level of the sea, and in which it contains three distinct groups of organic remains, the one rising in beautiful progression over the other.
My first statement regarding the system must be much the reverse of the one just quoted, for the fossils are remarkably numerous and in a state of high preservation. I have a hundred solid proofs by which to establish the truth of the assertion within less than a yard of me. Half my closet walls are covered with the peculiar fossils of the Lower Old Red Sandstone; and certainly a stranger assemblage of forms has rarely been grouped together—creatures whose very type is lost, fantastic and uncouth, which puzzle the naturalist to assign them even to their class; boat-like animals, furnished with oars and a rudder; fish, plated over, like the tortoise, above and below, with a strong armour of bone, and furnished with but one solitary rudder-like fin; other fish with the membranes of their fins thickly covered with scales; creatures bristling over with thorns; others glistening in an enamelled coat, as if beautifully japanned; the tail in every instance among the less equivocal shapes formed not equally, as in existing fish, on each side the central vertebral column, but chiefly on the lower side—the column sending out its diminished vertebræ to the extreme termination of the fin. All the forms testify of a remote antiquity. The figures on a Chinese vase or an Egyptian obelisk are scarce more unlike what now exists in nature than are the fossils of the Lower Old Red Sandstone.
Lamarck, on the strength of a few striking facts which prove that to a certain extent the instincts of species may be improved and heightened, has concluded that there is a natural progress from the inferior orders of being towards the superior, and that the offspring of creatures low in the scale may belong to a different and nobler species a few thousand years hence. Never was there a fancy so wild and extravagant. The principle of adaptation still leaves the vegetable a vegetable, and the dog a dog. It is true that it is a law of nature that the chain of being is in some degree a continuous chain, and the various classes of existence shade into each other. All the animal families have their connecting links. Geology abounds with creatures of the intermediate class.
Fishes seem to have been the master existences of two great geological systems, mayhap of three, ere the age of reptiles began. Now, fishes differ very much among themselves, some ranking nearly as low as worms, some nearly as high as reptiles; and we find in the Old Red Sandstone series of links which are wanting in the present creation, and the absence of which occasions a wide gap between the two grand divisions of fishes, the bony and the cartilaginous.
Of all the organisms of the system one of the most extraordinary is the pterichthys, or winged fish, which the writer had the pleasure of introducing to the acquaintance of geologists. Had Lamarck been the discoverer he would unquestionably have held that he had caught a fish almost in the act of wishing itself into a bird. There are wings which want only feathers, a body which seems to have been as well adapted for passing through the air as through water, and a tail with which to steer.
My first idea regarding it was that I had discovered a connecting link-between the tortoise and the fish. I submitted some of my specimens to Mr. Murchison, and they furnished him with additional data by which to construct the calculations he was then making respecting fossils, and they added a new and very singular link to the chain of existence in its relation to human knowledge. Agassiz confirmed the conclusions of Murchison in almost every particular, deciding at once that the creature must have been a fish.
Next to the pterichthys of the Lower Old Red Sandstone I shall place its contemporary the coccosteus of Agassiz—a fish which in some respects must have resembled it. Both were covered with an armour of thickly tubercled bony plates, and both furnished with a vertebrated tail. The coccosteus seems to have been most abundant. Another of the families of the ichthyolites of the Old Red Sandstone—the cephalaspis—seems almost to constitute a connecting link between fishes and crustaceans. In the present creation fishes are either osseous or cartilaginous, that is, with bony skeletons, or with a framework of elastic, semi-transparent animal matter, like the shark; and the ichthyolites of the Old Red Sandstone unite these characteristics, resembling in some respects the osseous and in others the cartilaginous tribes. Agassiz at once confirmed my suspicion that the ichthyolites of the Old Red Sandstone were intermediate. Though it required skill to determine the place of the pterichthys and coccosteus there could be no mistaking the osteolepis—it must have been a fish, and a handsome one, too. But while its head resembled the heads of the bony fishes, its tail differed in no respects from the tails of the cartilaginous ones. And so through the discovery of extinct species the gaps between existing species have been bridged.
III.—Place-Fixing in the Dim Past
The next step was to fix the exact place of the ichthyolites in the geological scale, and this I was enabled to do by finding a large and complete bed in situ. Its true place is a little more than a hundred feet above the top, and not much more than a hundred yards above the base of the great conglomerate.
The Old Red Sandstone in Scotland and in England has its lower, middle, and upper groups—three distinct formations. As the pterichthys and coccosteus are the characteristic ichthyolites of the Lower Old Red formation, so the cephalaspis distinguishes the middle or coronstone division of the system in England. When we pass to the upper formation, we find the holoptychius the most characteristic fossil.
These fossils are found in a degree of entireness which depends less on their age than on the nature of the rock in which they occur. Limestone is the preserving salt of the geological world, and the conservative qualities of the shales and stratified clays of the Lower Old Red Sandstone are not much inferior to limestone itself; while in the Upper Old Red the beds of consolidated sand are much less conservative of organic remains. The older fossils, therefore, can be described almost as minutely as the existence of the present creation, whereas the newer fossils exist, except in a few rare cases, as fragments, and demand the powers of a Cuvier or an Agassiz to restore them to their original combinations. On the other hand, while the organisms of the Lower Old Red are numerous and well preserved, those of the Upper Old Red are much greater in individual size. In short, the fish of the lower ocean must have ranged in size between a stickleback and a cod; whereas some of the fish of the ocean of the Upper Sandstone were covered with scales as large as oyster shells, and were armed with teeth that rivalled in size those of the crocodile.
IV.—Fish as Nature's Last Word
I will now attempt to present to the reader the Old Red Sandstone as it existed in time—during the succeeding periods of its formation, and when its existences lived and moved as the denizens of primeval oceans. We pass from the cemetery with its heaps of bones to the ancient city full of life and animation in all its streets and dwellings.
Before we commence our picture, two great geological periods have come to their close, and the floor of the widely spread ocean is occupied to the depth of many thousand feet by the remains of bygone existences. The rocks of these two earlier periods are those of the Cambrian and Silurian groups. The lower—Cambrian, representative of the first glimmering twilight of being—must be regarded as a period of uncertainty. It remains for future discoverers to determine regarding the shapes of life that burrowed in its ooze or careered through the incumbent waters.
There is less doubt respecting the existences of the Silurian rocks. Four distinct platforms of being range in it, the one over the other, like the stories of a building. Life abounded on all these platforms, and in shapes the most wonderful. In the period of the Upper Silurian fish, properly so called, and of a very perfect organisation, had taken precedence of the crustacean. These most ancient beings of their class were cartilaginous fishes, and they appear to have been introduced by myriads. Such are the remains of what seem to have been the first vertebrata.
The history of the period represented by the Old Red Sandstone seems, in what now forms the northern half of Scotland, to have opened amid confusion and turmoil. The finely laminated Tilestones of England were deposited evidently in a calm sea. During the contemporary period the space which now includes Orkney, Lochness, Dingwall, Gamrie, and many a thousand square miles besides, was the scene of a shallow ocean, perplexed by powerful currents and agitated by waves. A vast stratum of water-rolled pebbles, varying in depth from a hundred feet to a hundred yards, remains, in a thousand different localities, to testify to the disturbing agencies of this time of commotion, though it is difficult to conceive how the bottom of any sea could have been so violently and equally agitated for so greatly extended a space.
The period of this shallow and stormy ocean passed, and the bottom, composed of the identical conglomerate which now forms the summit of some of our loftiest mountains, sank to a depth so profound as to be little affected by tides and tempests. During this second period there took place a vast deposit of coarse sandstone strata, and the subsidence continued until fully ninety feet had overlaid the conglomerate in waters perfectly undisturbed. And here we find the first proof that this ancient ocean literally swarmed with life—that its bottom was covered with miniature forests of algae, and its waters darkened by immense shoals of fish. I have seen the ichthyolite bed where they were as thickly covered with fossil remains as I have ever seen a fishing-bank covered with herrings.
At this period some terrible catastrophe involved in sudden destruction the fish of an area at least a hundred miles from boundary to boundary, perhaps much more. The same platform in Orkney as in Cromarty is strewn thick with remains which exhibit unequivocally the marks of violent death. In what could it have originated? By what quiet but potent agency of destruction could the innumerable existences of an area perhaps ten thousand miles in extent be annihilated at once, and yet the medium in which they lived be left undisturbed by its operations? The thought has often struck me that calcined lime, cast out as ashes from some distant crater and carried by the winds, might have been the cause of the widely spread destruction to which the fossil organisms testify. I have seen the fish of a small trouting stream, over which a bridge was in the course of building, destroyed in a single hour, for a full mile below the erection, by a few troughfuls of lime that fell into the water when the centring was removed.
The period of death passed, and over the innumerable dead there settled a soft muddy sediment. For an unknown space of time, represented in the formation by a deposit about fifty feet in thickness, the waters of the depopulated area seem to have remained devoid of life. A few scales and plates then begin to appear. The fish that had existed outside the chasm seem to have gradually gained upon it as their numbers increased.
The work of deposition went on and sandstone was overlaid by stratified clay. This upper bed had also its organisms, but the circumstances were less favourable to the preservation of entire ichthyolites than those in which the organisms were wrapped up in their stony coverings. Age followed age, generations were entombed in ever-growing depositions. Vast periods passed, and it seemed as if the power of the Creator had reached its extreme limit when fishes had been called into existence, and our planet was destined to be the dwelling-place of no nobler inhabitants.
The curtain rises, and the scene is new. The myriads of the lower formation have disappeared, and we are surrounded on an upper platform by the existences of a later creation. Shoals of cephalaspides, feathered with fins, sweep past. We see the distant gleam of scales, that some of the coats glitter with enamel, that others bristle over with minute thorny points. A huge crustacean, of uncouth proportions, stalks over the weedy bottoms, or burrows in the hollows of the banks. Ages and centuries pass—who can sum up their number?—for the depth of this middle formation greatly exceeds that of the other two.
The curtain rises. A last day had at length come to the period of the middle formation, and in an ocean roughened by waves and agitated by currents we find new races of existences. We may mark the clumsy bulk of the Holoptychius conspicuous in the group. The shark family have their representative as before; a new variety of the pterichthys spreads out its spear-like wings at every alarm, like its predecessor of the lower formation. Fish still remained the lords of creation, and their bulk, at least, had become immensely more great. We began with an age of dwarfs, we end with an age of giants, which is carried on into the lower coal measures. We pursue our history no further?
Has the last scene in the series arisen? Cuvier asked the question, hesitated, and then decided in the negative, for he was too intimately acquainted with the works of the Creator to think of limiting His power, and he could anticipate a coming period in which man would have to resign his post of honour to some nobler and wiser creature, the monarch of a better and happier world.