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tween Ireland and Newfoundland, is found to historical nations, the workers of the chipped be a vast plain of deep-sea mud which is sub-flints of Hoxne1 or of Amiens2 are to them, as stantially chalk, deposited there by multitudes they are to us, in point of antiquity.

of organisms (Globigerina), which in life have the power of separating from the ocean the small proportion of carbonate of lime which is dissolved in sea-water, and of building that substance into skeletons for themselves.

Third. The living Globigerina are exclusively marine animals, and this, along with other evidence, compels the conclusion that the chalk beds of the dry land are the dried mud of an ancient deep sea.

Fourth. The thickness of the chalk bed and the character of its fossil remains prove that the period of deposit-the cretaceous epochwas of great duration.]

Thus not only is it certain that the chalk is the mud of an ancient sea-bottom; but it is no less certain that the chalk sea existed during an extremely long period, though we may not be prepared to give a precise estimate of the length of that period in years. The relative duration is clear, though the absolute duration may not be definable. The attempt to affix any precise date to the period at which the chalk sea began, or ended, its existence, is baffled by difficulties of the same kind. But the relative age of the cretaceous epoch may be determined with as great ease and certainty as the long duration of that epoch.

You will have heard of the interesting discoveries recently made in various parts of Western Europe of flint implements, obviously worked into shape by human hands, under circumstances which show conclusively that man is a very ancient denizen of these regions. It has been proved that the old populations of Europe, whose existence has been revealed to us in this way, consisted of savages, such as the Esquimaux are now; that, in the country which is now France, they hunted the reindeer, and were familiar with the ways of the mammoth and the bison. The physical geography of France was in those days different from what it is now the river Somme, for instance, having cut its bed a hundred feet deeper between that time and this; and it is probable that the climate was more like that of Canada or Siberia than that of Western Europe.

The existence of these people is forgotten even in the traditions of the oldest historical nations. The name and fame of them had utterly vanished until a few years back; and the amount of physical change which has been effected since their day renders it more than probable that, venerable as are some of the

But if we assign to these hoar relics of longvanished generations of men the greatest age that can possibly be claimed for them, they are not older than the drift, or boulder clay, which, in comparison with the chalk, is but a very juvenile deposit. You need go no further than your own sea-board for evidence of this fact. At one of the most charming spots on the coast of Norfolk, Cromer, you will see the boulder clay forming a vast mass, which lies upon the chalk, and must consequently have come into existence after it. Huge boulders of chalk are, in fact, included in the clay, and have evidently been brought to the position they now occupy by the same agency as that which has planted blocks of syenite from Norway side by side with them.

The chalk, then, is certainly older than the boulder clay. If you ask how much, I will again take you no further than the same spot upon your own coasts for evidence. I have spoken of the boulder clay and drift as resting upon the chalk. That is not strictly true. Interposed between the chalk and the drift is a comparatively insignificant layer, containing vegetable matter. But that layer tells a wonderful history. It is full of stumps of trees standing as they grew. Fir-trees are there with their cones, and hazel-bushes with their nuts; there stand the stools of oak and yew trees, beeches and alders. Hence this stratum is appropriately called the "forest-bed.''

It is obvious that the chalk must have been upheaved and converted into dry land before the timber trees could grow upon it. As the boles of some of these trees are from two to three feet in diameter, it is no less clear that the dry land thus formed remained in the same condition for long ages. And not only do the remains of stately oaks and well-grown firs testify to the duration of this condition of things, but additional evidence to the same effect is afforded by the abundant remains of elephants, rhinoceroses, hippopotamuses and other great wild beasts, which it has yielded to the zealous search of such men as the Rev. Mr. Gunn.4 When you look at such a collection as he has formed, and bethink you that these elephantine bones did veritably carry their owners about, and these great grinders crunch, in the dark 1 In Suffolk, England, where an important discovery of flint implements was made in 1797. 2 In northern France. 3 stumps

4 Robert Campbell Gunn (1808-1881), a British

naturalist.

woods of which the forest-bed is now the only trace, it is impossible not to feel that they are as good evidence of the lapse of time as the annual rings of the tree-stumps.

these later rocks, and for their upheaval into dry land, must have elapsed before the smallest brook which feeds the swift stream of "the great river, the river of Babylon,'' began to flow.

Thus there is a writing upon the walls of cliffs at Cromer, and whoso runs may read it. Thus, evidence which cannot be rebutted, and It tells us, with an authority which cannot be which need not be strengthened, though if time impeached, that the ancient sea-bed of the permitted I might indefinitely increase its quanchalk sea was raised up, and remained dry land | tity, compels you to believe that the earth, from until it was covered with forest, stocked with the time of the chalk to the present day, has the great game whose spoils have rejoiced your geologists. How long it remained in that conlition cannot be said; but "the whirligig of time brought its revenges ''5 in those days as in these. That dry land, with the bones and teeth of generations of long-lived elephants hidden away among the gnarled roots and dry leaves of its ancient trees, sank gradually to the bottom of the icy sea, which covered it with huge masses of drift and boulder clay. Sea-beasts, such as the walrus, now restricted to the extreme north, paddled about where birds had twittered among the topmost twigs of the firtrees. How long this state of things endured we know not, but at length it came to an end. The upheaved glacial mud hardened into the soil of modern Norfolk. Forests grew once more, the wolf and the beaver replaced the reindeer and the elephant; and at length what we call the history of England dawned.

Thus you have, within the limits of your own county, proof that the chalk can justly claim a very much greater antiquity than even the oldest physical traces of mankind. But we may go further and demonstrate, by evidence of the same authority as that which testifies to the existence of the father of men, that the chalk is vastly older than Adam himself.

The Book of Genesis informs us that Adam, immediately upon his creation, and before the appearance of Eve, was placed in the Garden of Eden. The problem of the geographical position of Eden has greatly vexed the spirits of the learned in such matters, but there is one point respecting which, so far as I know, no commentator has ever raised a doubt. This is, that of the four rivers which are said to run out of it, Euphrates and Hiddekel are identical with the rivers now known by the names of Euphrates and Tigris. But the whole country in which these mighty rivers take their origin, | and through which they run, is composed of rocks which are either of the same age as the chalk, or of later date. So that the chalk must not only have been formed, but, after its formation, the time required for the deposit of 5 Twelfth Night, V, i, 384.

been the theater of a series of changes as vast in their amount as they were slow in their progress. The area on which we stand has been first sea and then land, for at least four alternations; and has remained in each of these conditions for a period of great length. Nor have these wonderful metamorphoses of sea into land, and of land into sea, been confined to one corner of England. During the chalk period, or "cretaceous epoch," not one of the present great physical features of the globe was in existence. Our great mountain ranges, Pyrenees, Alps, Himalayas, Andes, have all been upheaved since the chalk was deposited, and the cretaceous sea flowed over the sites of Sinai and Ararat. All this is certain, because rocks of cretaceous, or still later date, have shared in the elevatory movements which gave rise to these mountain chains; and may be found perched up, in some cases, many thousand feet high upon their flanks. And evidence of equal cogency demonstrates that, though in Norfolk the forest-bed rests directly upon the chalk, yet it does so, not because the period at which the forest grew immediately followed that at which the chalk was formed, but because an immense lapse of time, represented elsewhere by thousands of feet of rock, is not indicated at Cromer.

I must ask you to believe that there is no less conclusive proof that a still more prolonged succession of similar changes occurred before the chalk was deposited. Nor have we any reason to think that the first term in the series of these changes is known. The oldest sea-beds preserved to us are sands, and mud, and pebbles, the wear and tear of rocks which were formed in still older oceans.

But, great as is the magnitude of these physical changes of the world, they have been accompanied by a no less striking series of modifications in its living inhabitants. All the great classes of animals, beasts of the field, fowls of the air, creeping things, and things which dwell in the waters, flourished upon the globe long ages before the chalk was deposited. Very few, 6 Genesis, XV, 18.

however, if any, of these ancient forms of ani- vegetation acquires a modern aspect. A few mal life were identical with those which now living animals are not even distinguishable as live. Certainly not one of the higher animals species from those which existed at that remote was of the same species as any of those now epoch. The Globigerina of the present day, in existence. The beasts of the field, in the for example, is not different specifically from days before the chalk, were not our beasts of that of the chalk; and the same may be said of the field, nor the fowls of the air such as those many other Foraminifera. I think it probable which the eye of man has seen flying, unless that critical and unprejudiced examination will his antiquity dates infinitely further back than show that more than one species of much higher we at present surmise. If we could be carried animals have had a similar longevity; but the back into those times, we should be as one sud-only example which I can at present give condenly set down in Australia before it was colo-fidently is the snake 's-head lamp-shell (Terenized. We should see mammals, birds, reptiles, bratulina caput serpentis), which lives in our fishes, insects, snails, and the like, clearly recog- English seas and abounded (as Terebratulina nizable as such, and yet not one of them would striata of authors) in the chalk. be just the same as those with which we are familiar, and many would be extremely dif ferent.

From that time to the present, the population of the world has undergone slow and gradual, but incessant changes. There has been no grand catastrophe-no destroyer has swept away the forms of life of one period and replaced them by a totally new creation; but one species has vanished and another has taken its place; creatures of one type of structure have diminished, those of another have increased, as time has passed on. And thus, while the differences between the living creatures of the time before the chalk and those of the present day appear startling if placed side by side, we are led from one to the other by the most gradual progress if we follow the course of Nature through the whole series of those relics of her operations which she has left behind.

The longest line of human ancestry must hide its diminished head before the pedigree of this insignificant shell-fish. We Englishmen are proud to have an ancestor who was present at the Battle of Hastings.8 The ancestors of Terebratulina caput serpentis may have been present at a battle of Ichthyosauria in that part of the sea which, when the chalk was forming, flowed over the site of Hastings. While all around has changed, this Terebratulina has peacefully propagated its species from generation to generation, and stands, to this day, as a living testimony to the continuity of the present with the past history of the globe.

Up to this moment I have stated, so far as I know, nothing but well-authenticated facts, and the immediate conclusions which they force upon the mind. But the mind is so constituted that it does not willingly rest in facts and immediate causes, but seeks always after a knowledge of the remoter links in the chain of causation. Taking the many changes of any given spot of the earth's surface, from sea to land and from land to sea, as an established fact, we cannot refrain from asking ourselves how these changes have occurred. we have explained them-as they must be explained-by the alternate slow movements of elevation and depression which have affected the crust of the earth, we go still further back and ask, Why these movements?

And when

And it is by the population of the chalk sea that the ancient and the modern inhabitants of the world are most completely connected. The groups which are dying out flourish side by side with the groups which are now the dominant forms of life. Thus the chalk contains remains of those strange flying and swimming reptiles, the pterodactyl, the ichthyosaurus, and the plesiosaurus, which are found in no later deposits, but abounded in preceding ages. The chambered shells called ammonites and belemnites, which are so characteristic of the period preceding the cretaceous, in like manner die I am not certain that anyone can give you with it. But amongst these fading remainders a satisfactory answer to that question. Assurof a previous state of things are some very mod-edly I cannot. All that can be said, for cerern forms of life, looking like Yankee pedlars tain, is that such movements are part of the among a tribe of Red Indians. Crocodiles of ordinary course of nature, inasmuch as they are modern type appear; bony fishes, many of them going on at the present time. Direct proof very similar to existing species, almost supplant may be given that some parts of the land of the forms of fish which predominate in more the northern hemisphere are at this moment inancient seas; and many kinds of living shell7 Paradise Lost, IV, 35. fish first become known to us in the chalk. The

8 The Norman Conquest, 1066.

sensibly rising and others insensibly sinking; the necessary alternative, that all these varied

and there is indirect, but perfectly satisfactory, proof that an enormous area now covered by the Pacific has been deepened thousands of feet since the present inhabitants of that sea came into existence. Thus there is not a shadow of a reason for believing that the physical changes of the globe in past times have been effected by other than natural causes. Is there any more reason for believing that the concomitant modifications in the forms of the living inhabitants of the globe have been brought about in other ways?

Before attempting to answer this question, let us try to form a distinct mental picture of what has happened in some special case. The crocodiles are animals which, as a group, have a very vast antiquity. They abounded ages before the chalk was deposited; they throng the rivers in warm climates at the present day. There is a difference in the form of the joints of the backbone, and in some minor particulars, between the crocodiles of the present epoch and those which lived before the chalk; but in the cretaceous epoch, as I have already mentioned, the crocodiles had assumed the modern type of structure. Notwithstanding this, the crocodiles of the chalk are not identically the same as those which lived in the times called "older tertiary," which succeeded the cretaceous epoch, and the crocodiles of the older tertiaries are not identical with those of the newer tertiaries, nor are these identical with existing forms. (I leave open the question whether particular species may have lived on from epoch to epoch.) Thus each epoch has had its peculiar crocodiles; though all, since the chalk, have belonged to the modern type, and differ simply in their proportions, and in such structural particulars as are discernible only to trained eyes.

How is the existence of this long succession of different species of crocodiles to be accounted for? Only two suppositions seem to be open to us-Either each species of crocodile has been specially created, or it has arisen out of some pre-existing form by the operation of natural causes. Choose your hypothesis; I have chosen mine. I can find no warranty for believing in the distinct creation of a score of successive species of crocodiles in the course of countless ages of time. Science gives no countenance to such a wild fancy; nor can even the perverse ingenuity of a commentator pretend to discover this sense in the simple words in which the writer of Genesis records the proceedings of the fifth and sixth days of the Creation. On the other hand, I see no good reason for doubting

species have been evolved from pre-existing crocodilian forms, by the operation of causes as completely a part of the common order of nature as those which have effected the changes of the inorganic world. Few will venture to affirm that the reasoning which applies to crocodiles loses its force among other animals, or among plants. If one series of species has come into existence by the operation of natural causes, it seems folly to deny that all may have arisen in the same way.

A small beginning has led us to a great ending. If I were to put the bit of chalk with which we started into the hot but obscure flame of burning hydrogen, it would presently shine like the sun. It seems to me that this physical metamorphosis is no false image of what has been the result of our subjecting it to a jet of fervent, though nowise brilliant, thought tonight. It has become luminous, and its clear rays, penetrating the abyss of the remote past, have brought within our ken some stages of the evolution of the earth. And in the shifting

without haste, but without rest'' of the land and sea, as in the endless variation of the forms assumed by living beings, we have observed nothing but the natural product of the forces originally possessed by the substance of the universe.

JOHN RUSKIN (1819-1900) FROM THE SEVEN LAMPS OF ARCHI

TECTURE*

THE LAMP OF MEMORY.

Among the hours of his life to which the writer looks back with peculiar gratitude as having been marked by more than ordinary fulness of joy or clearness of teaching, is one passed, now some years ago, near time of sunset, among the broken masses of pine forest which skirt the course of the Ain, above the village of Champagnole, in the Jura.1 It is a spot which has all the solemnity, with none of the savage"Ohne Hast, aber ohne Rast."-Goethe.

1 A chain of mountains in eastern France.

* Published in 1849, some time after the first two volumes of Modern Painters. The seven "Lamps" are Sacrifice, Truth, Power, Beauty, Life, Memory, and Obedience. The word "lamp" is used in allusion to the story of Aladdin's magic lamp; and the book was written, said Ruskin, "to show that certain right states of temper and moral feeling were the magic powers by which all good architecture, without exception, had been produced." The selection here given illustrates Ruskin's early exuberant style and also contains his fundamental doctrine of the necessity of relating art to life and morality.

curling pools of the green river gliding and glittering dizzily beneath him, their foam globes moving with him as he flew. It would be difficult to conceive a scene less dependent upon any other interest than that of its own secluded and serious beauty; but the writer well remembers the sudden blankness and chill which were cast upon it when he endeavoured, in order more strictly to arrive at the sources of its impressiveness, to imagine it, for a moment, a scene in some aboriginal forest of the New Continent. The flowers in an instant lost their light, the river its music; the hills became oppressively desolate; a heaviness in the boughs of the darkened forest showed how much of their former power had been dependent upon a life which was not theirs, how much of the glory of the imperishable, or continually renewed, creation is reflected from things more precious in their memories than it, in its renewing. Those ever springing flowers and ever flowing streams had been dyed by the deep colours of human endurance, valour, and virtue; and the crests of the sable hills that rose against the evening sky received a deeper worship, because their far shadows fell eastward over the iron wall of Joux,4 and the four-square keep of Granson.5

ness, of the Alps; where there is a sense of a great power beginning to be manifested in the earth, and of a deep and majestic concord in the rise of the long low lines of piny hills; the first utterance of those mighty mountain symphonies, soon to be more loudly lifted and wildly broken along the battlements of the Alps. But their strength is as yet restrained; and the far-reaching ridges of pastoral mountain succeed each other, like the long and sighing swell which moves over quiet waters from some faroff stormy sea. And there is a deep tenderness pervading that vast monotony. The destructive forces and the stern expression of the central ranges are alike withdrawn. No frost-ploughed, dust-encumbered paths of ancient glacier fret the soft Jura pastures; no splintered heaps of ruin break the fair ranks of her forests; no pale, defiled, or furious rivers rend their rude and changeful ways among her rocks. Patiently, eddy by eddy, the clear green streams wind along their well-known beds; and under the dark quietness of the undisturbed pines, there spring up, year by year, such company of joyful flowers as I know not the like of among all the blessings of the earth. It was spring time, too; and all were coming forth in clusters crowded for very love; there was room enough for all, but they crushed their leaves into all manner of strange shapes only to be nearer each other. There was the wood anemone, star after star, closing every now and then into nebulæ; and there was the oxalis, troop by troop, like virginal processions of the Mois de Maric,2 the dark vertical clefts in the limestone choked up with them as with heavy snow, and touched with ivy on the edges-ivy as light and lovely as the vine; and, ever and anon, a blue gush of violets, and cowslip bells in sunny places; and in the more open ground the vetch and comfrey, and mezereon, and the smali sapphire | buds of the Polygala Alpina,3 and the wild strawberry, just a blossom or two all showered amidst the golden softness of deep, warm, amber-coloured moss. I came out presently on the edge of the ravine; the solemn murmur of its waters rose suddenly from beneath, mixed with the singing of the thrushes among the pine boughs; and on the opposite side of the valley. walled all along as it was by gray cliffs of limestone, there was a hawk sailing slowly off their brow, touching them nearly with his wings, and with the shadows of the pines flickering 5 A village and castle on the Lake of Neuchâtel,

upon his plumage from above; but with the fall of a hundred fathoms under his breast, and the

2 "Mary's Month." The reference is to May processions in honor of the Virgin.

3 A milkwort.

It is as the centralization and protectross of this sacred influence, that Architecture is to be regarded by us with the most serious thought. We may live without her, and worship without her, but we cannot remember without her. How cold is all history, how lifeless all imagery, compared to that which the living nation writes, and the uncorrupted marble bears!-how many pages of doubtful record might we not often spare, for a few stones left one upon another! The ambition of the old Babel builders was well directed for this world: there are but two strong conquerors of the forgetfulness of men, Poetry and Architecture; and the latter in some sort includes the former, and is mightier in its reality; it is well to have, not only what men have thought and felt, but what their hands have handled, and their strength wrought, and their eyes beheld, all the days of their life. The age of Homer is surrounded with darkness, his very personality with doubt. Not so that of Pericles:7 and the day is coming when we shall

4 In the Fort de Joux, Mirabeau, the French orator. was once imprisoned; and Toussaint L'Ouverture, the Haitian revolutionist, died there.

Switzerland. A Swiss garrison was treacher ously put to death there by Charles the Bold in 1476 and gloriously avenged by the Swiss

army.

6 See Genesis. xl 4.

7 It was during the ascendency of Pericles that the Parthenon was built.

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