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English shore to thank Him for having brought j them so far on an enterprise so glorious. Two weeks; and what weeks! Wrecked, torn by cannon shot, ten thousand of them dead or dying—for this was the estimated loss by battle—the survivors could now but pray to be delivered from a miserable death by the elements. In cyclones the wind often changes suddenly back from northwest to west, from west to south. At that moment, as if in answer to their petition, one of these sudden shifts of wind saved them from the immediate peril. The gale backed round to S.8.W., and ceased to press them on the shoals. They could ease their sheets, draw off into open water, and steer a course up the middle of the North Sea.

So only that they went north, Drake was content to leave them unmolested. Once away into the high latitudes they might go where they would. Neither Howard nor he, in the low state of their own magazines, desired any unnecessary fighting. If the Armada turned back they must close with it. If it held its present course they must follow it till they could be assured it would communicate no more for that summer with the Prince of Parma. Drake thought they would perhaps make for the Baltic or some port in Norway. They would meet no hospitable reception from either Swedes or Danes, but they would probably try. One only imminent danger remained to be provided against. If they turned into the Forth, it was still possible for the Spaniards to redeem their defeat, and even yet shake Elizabeth's throne. Among the many plans which had been formed for the invasion of England, a landing in Scotland had long been the favourite. Guise had always preferred Scotland when it was intended that Guise should be the leader. Santa Cruz had been in close correspondence with Guise on this very subject, and many officers in the Armada must have been acquainted with Santa Cruz's views. The Scotch Catholic nobles were still savage at Mary Stuart's execution, and had the Armada anchored in Leith Roads* with twenty thousand men, half a million ducats, and a Santa Cruz at its head, it might have kindled a blaze at that moment from John o 'Groat's Landr> to the Border.

But no such purpose occurred to the Duke of Medina Sidonia. He probably knew nothing at all of Scotland or its parties. Among the many deficiencies which he had pleaded to Philip as unfitting him for the command, he had said that Santa Cruz had acquaintances

4 On the Firth of Forth, 5 The northwestern exnear Edinburgh. tremity of Scotland.

j among the English and Scotch peers. He had | himself none. The small information which he had of anything did not go beyond his orange gardens and his tunny fishing. His chief merit was that he was conscious of his incapacity; and, detesting a service into which he had been fooled by a hysterical nun,* his only anxiety was to carry home the still considerable fleet which had been trusted to him without further loss. Beyond Scotland and the Scotch isles there was the open ocean, and in the open ocean there were no sandbanks and no English guns. Thus, with all sail set, he went on before the wind. Drake and Howard attended him till they had seen him past the Forth, and knew then that there was no more to fear. It was time to see to the wants of their own poor fellows, who had endured so patiently and fought so magnificently. On the 13th day of August they saw the last of the Armada, turned back, and made their way to the Thames-t

THOMAS HENRY HUXLEY
(1825-1895)

ON A PIECE OF CHALK.+.

If a well were to be sunk at our feet in the midst of the city of Norwich, the diggers would very soon find themselves at work in that white substance, almost too soft to be called rock, with which we are all familiar as "chalk." Not only here, but over the whole county of Norfolk, the well-sinker might carry his shaft down many hundred feet without coming to the end of the chalk; and, on the sea-coast, where the waves have pared away the face of the land which breasts them, the scarped faces of the high cliffs are often wholly formed of the same material. Northward, the chalk may be followed as far as Yorkshire; on the south

* A nun at Lisbon had told the wavering Duke that "Our Lady had sent her to promise him

success."

t The remainder of the narrative is the Btory of the disasters that attended the Spanish In their voyage around Scotland and Ireland. Many died from exposure, scanty food, and poisonous water: many were wrecked; even of those who reached Spain alive, few ever rallied from the experience.

t A lecture delivered to the working men of Norwich, England, and printed in UaemiUon's Magazine, 1868: now In Lay Sermons, Addresses and Reviews. Some changes have here been made in paragraphing and punctuation. For clearness of exposition Huxley has few or no superiors, but the system of paragraphing employed in his works as they are ordinarily printed not Infrequently has an obscuring effect.

coast it appears abruptly in the picturesque' western bays of Dorset, and breaks into the ] Needles' of the Isle of Wight; while on the shores of Kent it supplies that long line of i white cliffs to which England owes her name j of Albion.

Were the thin soil which covers it all washed | away, a curved band of white chalk, here broader and there narrower, might be followed diagonally across England from Lulworth in Dorset j to Klamborough Head in Yorkshire—a distance of over two hundred and eighty miles as the j crow Hies, from this band to the >>orth Sea, on the east, and the Channel, on the south, the chalk is largely hidden by other deposits; but, except in the Wealdt of Kent and Sussex, it enters into the very foundation of all the j south-eastern counties.

Attaining, as it does in some places, a thickness of more than a thousand feet, the English chalk must be admitted to be a mass of consid- j erable magnitude. Nevertheless, it covers but j an insignificant portion of the whole area occupied by the chalk formation of the globe, which j has precisely the same general characters us our.", and is found in detached patches, some less anil others more extensive than the English. Chalk occurs in northwest Ireland; it stretches over, a large part of France,—the chalk which un-; derlies Paris being, in fact, a continuation of that of the London basin; runs through Denmark and Central Europe, and extends southward to North Africa; while eastward, it appears in the Crimea and in Syria, anil may be traced as far as the shores of the Sea of Aral, in Central Asia. If all the points at which true chalk occurs were circumscribed, they would lie within an irregular oval about three thousand miles in long diameter, the area of which would be as great as that of Europe, and would many times exceed that of the largest existing inland sea—the Mediterranean.

Thus the chalk is no unimportant element in the masonry of the earth's crust, and it impresses a peculiar stamp, varying with the conditions to which it is exposed, on the scenery of the districts in which it occurs. The undulating downs and rounded coombs-, covered with sweet-grassed turf, of our inland chalk country, have a peacefully domestic and mutton-suggesting prettiness, but can hardly bo called either grand or beautiful. But on our southern coasts.

1 Three white rocks rlsine nhruptlv from the sen

to the beiKbt of 100 feet.

2 Latin albn/t. "white."

a Or combs; bowl-shapeil valleys.

t This name for the region is old: Anclo-Saxon trmlil (German Wnhl) means "forest." Compare Onxlim's aicount of his liirili. p. f)."..

the wall-sided cliffs, many hundred feet high, with vast needles and pinnacles standing out in the sea, sharp and solitary enough to serve as perches for the wary cormorant, confer a wonderful beauty and grandeur upon the chalk headlands. And in the East, chalk has its share in the formation of some of the most venerable of mountain ranges, such as the Lebanon.

What is this wide-spread component of the surface of the earth? and whence did it comet

You may think this no very hopeful inquiry. Y'ou may not unnaturally suppose that the attempt to solve such problems as these can lead to no result, save that of entangling the inquirer in vague speculations, incapable of refutation and of verification. If such were really the case, 1 should have selected some other subject than a "piece of chalk" for my discourse. But in truth, after much deliberation, I have been unable to think of any topic which would so well enable me to lead you to see how solid is the foundation upon which some of the most startling conclusions of physical science rest. A great chapter in the history of the world is written in the chalk. Few passages in the history of man can be supported by such an overwhelming mass of direct and indirect evidence .is that which testifies to the truth of the fragment of the history of the globe which I hope to enable you to read, with your own eyes, tonight.

Let me add that few chapters of human history have a more profound significance for ourselves. I weigh my words well when I assort that the man who should know the true history of the bit of chalk which every carpenter carries about in his breeches pocket, though ignorant of all other history, is likely, if he will think his knowledge out to its ultimate results, to have a truer, and therefore a better, conception of this wonderful universe, and of man's relation to it. than the most learned student who is deep read in the records of humanity and ignorant of those of Nature. The language of the chalk is not hard to learn, not nearly so hard as Latin, if you only want to get at the liroad features of the story it has to tell; and I propose that w e now set to work to spell that story out together. .

[In the intervening portion of his address Huxley sets forth the following facts:

First. Chemically, chalk consists of earlionie acid and quicklime. Under the microscope it is seen to be made up of granules in which are imbedded numerous calcareous skeletons known

:IS (rlobifJClilHF.

Second. The bed of the North Atlantic, between Ireland ami Newfoundland, is found to he a vast plain of deep-sea mini which is substantially chalk, deposit0(1 there by multitudes of organisms (Globigvrinte), 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 Globir/erium 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 epoch— was of great duration. 1

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

'historical nations, the workers of the chipped flints of Hoxne' or of Amiens- are to them, as they are to us, in point of antiquity.

But if we assign to these hoar relics of longvanished generations of men the greatest age that can possibly be claimed for them, they arc 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.

i 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.

1 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.< When you look at such a collection as he has formed, and bethink you that these elephantine hones did veritably carry their owners about, and these great grinders crunch, in the dark

I In Suffolk. England, where an important discovery of flint implements was made in 1707. •2 In northern France. ■i stumps

t 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.

Thus there is a writing upon the walls of cliffs at Cromer, and whoso runs may read it. It tells us, with an authority which cannot be impeached, that the ancient sea-bed of the chalk sea was raised up, and remained dry land until it was covered with forest, stocked with the great game whose spoils have rejoiced your geologists. How long it remained in that condition cannot be said; but "the whirligig of time brought its revenges''» 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 arc 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 Ticelfih Night, V. i, 384.

'these later rocks, and for their upheaval into I 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, evidence which cannot be rebutted, and which need not be strengthened, though if time permitted I might indefinitely increase its quantity, compels you to believe that the earth, from the time of the chalk to the present day, has 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 I 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,

ii Genesis, xv, 18.

however, if any, of these ancient forms of animal life were identical with those which now live. Certainly not one of the higher animals was of the same species as any of those now in existence. The beasts of the field, in the days before the chalk, were not our beasts of the field, nor the fowls of the air such as those which the eye of man has seen flying, unless his antiquity dates infinitely further back than we at present surmise. If we could be carried back into those times, we should be aB one suddenly set down in Australia before it was colonized. We should see mammals, birds, reptiles, fishes, insects, snails, and the like, clearly recognizable as such, and yet not one of them would be juBt the same as those with which we are familiar, and many would be extremely different.

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 dif- | ferences 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.

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 plesioBaurus, 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 with it. But amongst these fading remainders of a previous state of things are some very modern forms of life, looking like Yankee pedlars among a tribe of Red Indians. Crocodiles of modern type appear; bony fishes, many of them very similar to existing species, almost supplant the forms of fish which predominate in more ancient seas; and many kinds of living shellfish first become known to us in the chalk. The

vegetation acquires a modern aspect. A few living animals are not even distinguishable as species from those which existed at that remote epoch. The Globigerina of the present day, for example, is not different specifically from that of the chalk; and the same may be said of many other Foraminifcra. 1 think it probable that critical and unprejudiced examination will show that more than one species of much higher animals have had a similar longevity; but the only example which I can at present give confidently is the snake 's-head lamp-shell (Terebratulina caput serpentis), which lives in our English seas and abounded (as Terebratulina striata of authors) in the chalk.

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 anund 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. And when 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?

I am not certain that anyone can give you a satisfactory answer to that question. Assuredly I cannot. All that can be said, for certain, is that such movements are part of the ordinary course of nature, inasmuch as they are going on at the present time. Direct proof may be given that some parts of the land of the northern hemisphere are at this moment in

7 Paratlite Lost. IV. 35.

» The Norman Conquest, 1066.

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