We now enter upon the ancient life, or Palæozoic period of the earth’s history, and proceed to examine the oldest forms of life, or the most ancient organic remains found in the crust of the earth. As we do not aim to teach geology in this small work, but simply to place the chief geological facts in such a light as to impart a taste for the science, the reader will not expect any minute details, which are more likely to perplex than to assist the beginner. Let the reader dismiss from his mind all that he has tried to remember about Upper and Lower Silurian rocks, and the Upper and Lower Ludlow rocks, the Caradoc sandstone and the Llandilo flags, and so on; let us simply say that one part of the crust of the earth, supposed to be between 50,000 and 60,000 feet in thickness,[[28]] is called the Silurian system, and constitutes a large and interesting part of the Palæozoic period. The term Silurian was given to this part of the earth’s crust in consequence of these rocks being found chiefly in Wales, Devon, and Cornwall—parts of England once inhabited by the Silures, who under Caractacus made so noble a stand against the Romans.
In coming for the first time into contact with the organic remains of pre-Adamite creations, it may be well to entreat the student to mark, as he goes on, the very different and characteristic fossils of the several formations through which we propose to travel. There will be little or no difficulty in doing this, and its mastery will be of invaluable service in our after researches. There is and there can be no royal road to any kind of learning; all, therefore, that we propose to do is to take a few of the big stones, boulders, &c., that have needlessly been allowed to make the road rougher than necessary, out of the way, that thus our companion traveller on this geologic route may feel that every step of ground walked over is a real and solid acquisition. In marking the characteristic fossils of each formation, let us suggest, in passing, the vast amount of pleasure there is in going to a friend’s house, and looking at the minerals or organic remains that may be in the cabinet or on the mantel-shelf, and being able to take them up one by one, and to say this is from the Silurian; that is from the Carboniferous; this is from the Cretaceous, and that from the Wealden formations, and so on. Why, it gives a magical feeling of delightful interest to every object we see, and will always make a person a welcome visitor with friends with whom, instead of talking scandal, he can talk geology. Not long since the writer had a very pleasing illustration of this. He had been lecturing on geology in a small agricultural village; there was a good sprinkling of smock-frocks among the hearers, and he said at the close of one of the lectures, “Now, very likely most of you have got some stones, as you call them, at home on the chimneypiece; perhaps you don’t know their names, or what they were before they became stones; well, bring them next week, and we will do our best to name them for you!” Next week, after the lecture, up came one, and then another, and then a third, and so on; and diving their hands down into the old orthodox agricultural pocket, brought out a variety of specimens, some of them very good indeed, which had been “picked up” by them in the course of their labour, and which, supposed to be “rather kūrŭss,” had been carefully conveyed home. When these matters were given a “local habitation and a name,” the delight of many was most gratifying.
Now, all this is only just the application of M. Cousin’s words in relation to physical geography: “Give me the map of a country, its configuration, its climate, its waters, its winds, and all its physical geography; give me its natural productions, its flora and fauna, and I pledge myself to tell you à priori what the inhabitants of that country will be, and what place that country will take in history, not accidentally, but necessarily; not at a particular epoch, but at all periods of time; in a word, the thought that country is formed to represent.”
These remarks furnish us with a clue. Each formation has its own peculiar and characteristic fossils, and these fossils are arranged with as much care, and preserved as uninjured, as if they had been arranged for a first-class museum. But before proceeding on this fossiliferous tour, we may anticipate a question that may possibly be asked on the threshold of our inquiries, and into which we propose going fully in the sequel of this volume. It may be asked, “Were not these fossils placed in the rocks by the Deluge?” To this, at present, we answer, that so partial and limited was the character of the Deluge, being confined to just so much of the earth as was inhabited by man, and so brief was its duration, compared with the vast geological epochs we shall have to consider, that we do not believe we have one single fossil that can be referred to the Noachian deluge; and before we close, we trust it will have been made evident to every careful reader that fossils, as records of Noah’s flood, are an impossibility; and that the vast antiquity of the globe, taken into connexion with the prevalence of death on a most extensive scale, ages and ages previous to the creation of man, can alone account for our innumerable treasures of the “deep places of the earth.”
1
The characteristic fossils of the Silurian system are entirely unique. The trilobite may fairly be regarded as the prominent one; besides which there are orthoceratites, and graptolites, some members of the crinoidean family, with different kinds of corallines, and some other names to be rendered familiar only by future further study. We shall confine ourselves to those that our own recent researches have made us familiar with. First, here is the trilobite. We need not perplex our readers by any of the numerous subdivisions of this remarkable animal’s nomenclature; that would defeat the purpose of this book. Any work on geology will do this.[[29]] Here are three trilobites: one (1) by itself; another, (2) imperfect in its bed or matrix, and a third (3) rolled up.
This most remarkable crustacean possessed the power of rolling itself up like the wood-louse or the hedgehog; and, reasoning by analogy, we suppose this to have been its defence against its numerous enemies. It is a very abundant fossil, found all over Europe, in some parts of America, at the Cape of Good Hope, but never in more recent strata than the Silurian. The hinder part of the body is covered with a crescent-like shield, composed of segments like the joints of a lobster’s tail; and two furrows divide it into three lobes, whence its name.[[30]] Most remarkable are the eyes of this animal, and it is the only specimen in the vestiges of ancient creations in which the eye, that most delicate organization, is preserved; and if, as we believe, this little creature was living and swimming about, now and then fighting with some greater Cephalopodous mollusk, millions and millions of years ago, then in this fact we have the real fossil poetry of science, the romance of an ancient world which geology reveals to our delighted and astonished minds. From Buckland’s Bridgewater Treatise we give a drawing of the eyes of the trilobite; and in Buckland’s words we add: “This point deserves peculiar consideration, as it affords the most ancient, and almost the only example yet found in the fossil world, of the preservation of parts so delicate as the visual organs of animals that ceased to live many thousands, and perhaps millions of years ago. We must regard these organs with feelings of no ordinary kind, when we recollect we have before us the identical instruments of vision through which the light of heaven was admitted to the sensorium of some of the first created inhabitants of our planet.”[[31]]
