LESSON XII.
A MOUNTAIN OF FOSSILS.
“The bleakest rock, upon the loneliest heath,Feels in its barrenness some touch of spring,And in the April dew, or beam of May,As moss and lichen freshen and revive.”
“The bleakest rock, upon the loneliest heath,Feels in its barrenness some touch of spring,And in the April dew, or beam of May,As moss and lichen freshen and revive.”
“The bleakest rock, upon the loneliest heath,Feels in its barrenness some touch of spring,And in the April dew, or beam of May,As moss and lichen freshen and revive.”
“The bleakest rock, upon the loneliest heath,
Feels in its barrenness some touch of spring,
And in the April dew, or beam of May,
As moss and lichen freshen and revive.”
—Beaumont.
Each successive age of the world brought forth its children, nourished them to their prime, accompanied them in the stages of their decay, and laid them in the tomb. Eachnew age rocked its cradles above the cemeteries of the age that had preceded it. Some sea-bed swarming with corals and mollusks was slowly lifted; in the shallow waters, sand, chalk, or clay were deposited, and gradually formed thick beds above the “swarmers,” which had suffocated in the mud, or, having lived out their span, had failed to reproduce their like. So in successive strata the present surface of the world was built, and sometimes in throes of uplifting, some long-buried stratum was doubled upon itself, and having been thrust up through deposits lying above it, once more reached sunlight. But it spread out into the sunlight not living creatures, but their sepulchres.
Let us now make a journey to one of the world’s wonderful graveyards. It is, in the first instance, wonderful for its great age. Is it then that acre on Coles’ Hill, sown with the graves of those who came in the Mayflower, with sweet Rose Standish in their midst? No; that in comparison is but of yesterday. Is it the graveyard at Battle Abbey, where, after the defeat of Harold the Saxon, Norman and Saxon lay down together in the peace of death? No; that in comparison is most modern. Is it the rock tombs of the Pharaohs before Moses? No; those tombs compared with this graveyard are newest possible fashions. The dead Pharaohs lie in their tombs in Egypt, with their servants and even the beasts and birds of their day, all turned into mummies. These mummies are so hard that many thousands of them have been chopped up for fuel by the Egyptians. This is a queer use for dead kings!
The creatures laid in the burial-ground where we shallnow go, are turned not into wood, but stone. I think I see the little genii and gnomes guarding them well through all the countless ages since they died.
Come then to this very ancient burial-ground. We trot briskly over a long, level stretch of prairie land, and now our stout horses fall from trotting to walking slowly up the steep hill. The wheels grind on the bare rocks; on the road-sides among the gray stones gleam patches of cinquefoil, blue-grass, and strawberry. Now the long faces of the horses no longer front the ascent, but the sharp crest is reached, and they look down upon the narrow valley into which the road suddenly falls. Across the valley lifts another range of hills, and these are colored like a map of various countries, by the masses of white dog-wood, rosy red-bud, purple birch in its soft springtime haze, green of young maple leaves, and the gold, rose, and bronze of the unfolding oak leaves.
Just here, in the midst of this flowery beauty, the roving eye detects on the road-side a gravestone with a well-cut inscription. Lo! here we are in one of the world’s most ancient burial-grounds. Here are the monuments; here the mummy-cases; here are the unburied bones. We can scoop them up by handfuls. How old is this graveyard? Who can tell? How long are the ages of geology? No doubt these dead were laid down here hundreds of thousands of years ago. Most ancient then is it not, and well worthy of our visit?
But quite as wonderful as the antiquity of this graveyard is the place where we find it. Here we stand: nine hundred miles to the east of us, as the crow flies, theAtlantic surges beat upon the coast, and wear away and rebuild the boundaries of our land. Two thousand miles to the west, lies the Pacific; nine hundred miles south, the Gulf of Mexico warms the Gulf Stream in its sunny bosom. Three thousand miles to the north, the Arctic Ocean, which no keel has ever crossed, groans and growls under the ice-floes. Very far from the seas are we not? What station could be more truly inland? And yet this graveyard is built up of corals and sea-shells and strange sea-creatures lie buried here.
Over this height where we stand the waves have thundered. Here was “a yellow beach of sand”; here the busy coral polyp built its palaces up, up, up, from sea-bottom to sunshine. These are not pebbles crunching here beneath our feet, but sea-shells, mollusks of the prime. This is the burial-ground of fishes and of zoöphytes. Is not this burial-ground wonderful for its locality?
And again it is wonderful for the distance which we must travel to find it. What is that? Did we not come here in a carriage, driving over a few easy miles, in a May morning? Let us see about that. Let me take you by the hand and lead you the real distance you must travel to reach this ancient burial-ground. Brace up your nerves, for we have to journey with the speed of thought, which is swifter even than light.
Our starting-point is this modern age of the world, the age which has brought forth grasses, palms, fruits, the higher mammals—man. Swiftly we traverse this age, and leave its landmarks far behind us, as we pass them with our faces set toward the old, old world. This modern age is one of thefive divisions of the Neozoic, ornewperiod. Through all the five we go, and at the gate of the one called the Eocene we pass out from under the palm shadows, from the mammals ranging in the forests and feeding on the green savannahs, and now we are back in the middle time, the age of the reptiles. The forests are dark with cycads and pines. Crocodiles, alligators, salamanders of very old-fashioned patterns, swarm the brakes and the bayous. Rushing above our heads go skin-winged flying things, with the tails and hands of lizards, and they crowd and cry about us for three ages more.
We must needs be brave as knights as we go back deeper still into mystery and antiquity, and by the door of the earliest reptilian age we find our way into the longest of the epochs, the time with six ages, the age which saw the coal-beds laid down and so many fossils locked up in rock—the Paleozoic[28]time.
We now find about us tree-ferns, club-mosses, reeds, calamites, lichens. There are fishes swarming in the warm seas; a few insects and spiders crawl among the ferns; here and there are toads, newts, and scorpions of curious patterns. One, two, three, four, five ages back we wander, and now the mosses and pines, the fishes and reptiles have disappeared, and we are in the age of sea-weeds and corals, crabs and mollusks, such as have few types in the modern world. And here, in the lower-Silurian, we have arrived at our ancient burial-ground. Have we not come a long way to find it?
Is there no shorter way to reach it? We have come here by the every-day style of a carriage over a few miles of plain and hill. We have come here also by a dash in imagination through three great times and thirteen busy ages of world-building. We can take yet a third way. Go yonder to the valley and sink a shaft for seven hundred feet, and you will pass through these ages and times and reach the era of this burial-ground. There it is hidden seven hundred feet deep; here it crops out into the sunshine; here have been tumult and convulsion, and what in some places might be thousands of feet below the surface, is here thrust up among modern methods, among apple trees, and bleating sheep, and white cottages, and little children at their play.
There is still another method of reaching this same burial-ground. Go into the valley and wander five miles toward the mouth of the little creek that divides it. As you touch its grassy bank you stand in the modern age of the present earth-building time. As you travel down the creek, the successive beds or stages of earth-building are laid bare, one after another, until at the end of five miles you stand on the lower-Silurian stratum of this burial-ground. Take a pamphlet, fold the first leaf over one half, the next a little less, and so on for thirteen pages, and you have a pattern of the manner in which the spring and autumn torrents flushing the brook have laid bare the rock strata, and shown them as they lie here closely crowded upon each other.
This is, however, an unusual case, for each of these ages has in many places left deposits thousands of feet in thickness. Here the uncovering has been rapid, deposit light, andwe can turn over the geologic pages in a volume a few hundreds of feet thick.
And having reached this ancient burial-ground by all these various lines of travel, what do we find here? Stoop and gather a handful of these little gray stones—small pebbles did you call them? The frost and rain of the past winter have washed away the sand and light soil which had hidden them. Why! these are shells, not pebbles. Stone shells, fossil shells! See how perfect every delicate fluting is, how sharply the hinge of the long-perished bivalve is defined. Some are of a delicate pale gray, others almost white; but long ago in the Silurian seas perhaps they shone in brown and yellow, red, pink, buff, and maroon, as gaily as the scallop shells of to-day, which in shape they much resemble.
What is this lump of stone covered with little star-shaped knobs? Trace the lines along the side where it was broken from some larger fragment, and they seem to branch; is it like the veins on a leaf? No; rather like the branches of coral, and in fact that is just what we have found,—a lump of fossilized coral of the Silurian age. The lower-Silurian was the age when coral was king. When after the two earlier epochs with their meagre fauna the Silurian age opened, suddenly the seas swarmed with life. They were warm tropic seas, warmer than any on the globe to-day, and in them these industrious coral-polyps built their towers. They built up from the sea-bottom to sunshine, and from each of these star-like towers a living creature unfurled itself like a flower, just beneath the surface of the sea. In orange,scarlet, purple, white, and pink, they expanded their coronals of filaments, and waved to and fro with the warm tides. No flower-garden ever bloomed more gorgeously than did these gardens of the sea in the Silurian age. Plume-like, fine as the stamens of a flower, these myriads of living things leaned from the towers and palaces themselves had built, and drank and fished in these clear seas under the glow of the sun.
Meanwhile among and around about these coral towers, cuttle-fish and nautili darted, while mailed crustaceans chased each other, fought and frolicked and devoured each other. See, we have another fossil in the rock, the beautiful stone lilies; they must have a chapter to themselves; and here again are lamp shells and other and different mollusks of the Silurian time. Here they were crowded, swimming and playing in these living coral bowers. How they were dashed by thousands upon this beach of sand! And by and by when life was in its prime, what strange mishaps overtook them all? Did the seas grow too hot or too cold? Did the bed of ocean rise? Did great sand-waves roll in among the coral bowers? They had had their day, another age was drawing on; there would be mollusks and crabs and crustaceans still, but these must perish and be locked up in this burial-ground. O gnomes and genii, keep your treasures well!
FOOTNOTES:[28]Pay-lee-o-zo-ic.
[28]Pay-lee-o-zo-ic.
[28]Pay-lee-o-zo-ic.