§ 1.Closebeside the path by which travellers ascend the Montanvert from the valley of Chamouni, on the right hand, where it first begins to rise among the pines, there descends a small stream from the foot of the granite peak known to the guides as the Aiguille Charmoz. It is concealed from the traveller by a thicket of alder, and its murmur is hardly heard, for it is one of the weakest streams of the valley. But it is a constant stream; fed by a permanent though small glacier, and continuing to flow even to the close of the summer, when more copious torrents, depending only on the melting of the lower snows, have left their beds "stony channels in the sun."
I suppose that my readers must be generally aware that glaciers are masses of ice in slow motion, at the rate of from ten to twenty inches a day, and that the stones which are caught between them and the rocks over which they pass, or which are embedded in the ice and dragged along by it over those rocks, are of course subjected to a crushing and grinding power altogether unparalleled by any other force in constant action. The dust to which these stones are reduced by the friction is carried down by the streams which flow from the melting glacier, so that the water which in the morning may be pure, owing what little strength it has chiefly to the rock springs, is in the afternoon not only increased in volume, but whitened with dissolved dust of granite, in proportion to the heat of the preceding hours of the day, and to the power and size of the glacier which feeds it.
§ 2. The long drought which took place in the autumn of the year 1854, sealing every source of waters except these perpetual ones, left the torrent of which I am speaking, and such others, in a state peculiarly favorable to observance of theirleastaction on the mountains from which they descend. They were entirely limited to their own ice fountains, and the quantity of powdered rock which they brought down was, of course, at its minimum, being nearly unmingled with any earth derived from the dissolution of softer soil, or vegetable mould, by rains.
At three in the afternoon, on a warm day in September, when the torrent had reached its average maximum strength for the day, I filled an ordinary Bordeaux wine-flask with the water where it was least turbid. From this quart of water I obtained twenty-four grains of sand and sediment, more or less fine. I cannot estimate the quantity of water in the stream; but the runlet of it at which I filled the flask was giving about two hundred bottles a minute, or rather more, carrying down therefore about three quarters of a pound of powdered granite every minute. This would be forty-five pounds an hour; but allowing for the inferior power of the stream in the cooler periods of the day, and taking into consideration, on the other side, its increased power in rain, we may, I think, estimate its average hour's work at twenty-eight or thirty pounds, or a hundred weight every four hours. By this insignificant runlet, therefore, some four inches wide and four inches deep, rather more than two tons of the substance of the Mont Blanc are displaced, and carried down a certain distance every week; and as it is only for three or four months that the flow of the stream is checked by frost, we may certainly allow eighty tons for the mass which it annually moves.
§ 3. It is not worth while to enter into any calculation of the relation borne by this runlet to the great torrents which descend from the chain of Mont Blanc into the valley of Chamouni. To call it the thousandth part of the glacier waters, would give a ludicrous under-estimate of their total power; but even so calling it, we should find for result that eighty thousand tons of mountain must be yearly transformed into drifted sand, and carried down a certain distance.49How much greater than this is the actual quantity so transformed I cannot tell;but take this quantity as certain, and consider that this represents merely the results of the labor of the constant summer streams, utterly irrespective of all sudden falls of stones and of masses of mountain (a single thunderbolt will sometimes leave a scar on the flank of a soft rock, looking like a trench for a railroad); and we shall then begin to apprehend something of the operation of the great laws of change, which are the conditions of all material existence, however apparently enduring. The hills, which, as compared with living beings, seem "everlasting," are, in truth, as perishing as they: its veins of flowing fountain weary the mountain heart, as the crimson pulse does ours; the natural force of the iron crag is abated in its appointed time, like the strength of the sinews in a human old age; and it is but the lapse of the longer years of decay which, in the sight of its Creator, distinguishes the mountain range from the moth and the worm.
§ 4. And hence two questions arise of the deepest interest. From what first created forms were the mountains brought into their present condition? into what forms will they change in the course of ages? Was the world anciently in a more or less perfect state than it is now? was it less or more fitted for the habitation of the human race? and are the changes which it is now undergoing favorable to that race or not? The present conformation of the earth appears dictated, as has been shown in the preceding chapters, by supreme wisdom and kindness. And yet its former state must have been different from what it is now; as its present one from that which it must assume hereafter. Is this, therefore, the earth's prime into which we are born; or is it, with all its beauty, only the wreck of Paradise?
I cannot entangle the reader in the intricacy of the inquiries necessary for anything like a satisfactory solution of these questions. But, were he to engage in such inquiries, their result would be his strong conviction of the earth's having been brought from a state in which it was utterly uninhabitable into one fitted for man;—of its having been, when first inhabitable, more beautiful than it is now; and of its gradually tending to still greater inferiority of aspect, and unfitness for abode.
It has, indeed, been the endeavor of some geologists to provethat destruction and renovation are continually proceeding simultaneously in mountains as well as in organic creatures; that while existing eminences are being slowly lowered, others, in order to supply their place, are being slowly elevated; and that what is lost in beauty or healthiness in one spot is gained in another. But I cannot assent to such a conclusion. Evidence altogether incontrovertible points to a state of the earth in which it could be tenanted only by lower animals, fitted for the circumstances under which they lived by peculiar organizations. From this state it is admitted gradually to have been brought into that in which we now see it; and the circumstances of the existing dispensation, whatever may be the date of its endurance, seem to me to point not less clearly to an end than to an origin; to a creation, when "the earth was without form and void," and to a close, when it must either be renovated or destroyed.
§ 5. In one sense, and in one only, the idea of a continuous order of things is admissible, in so far as the phenomena which introduced, and those which are to terminate, the existing dispensation, may have been, and may in future be, nothing more than a gigantic development of agencies which are in continual operation around us. The experience we possess of volcanic agency is not yet large enough to enable us to set limits to its force; and as we see the rarity of subterraneous action generally proportioned to its violence, there may be appointed, in the natural order of things, convulsions to take place after certain epochs, on a scale which the human race has not yet lived long enough to witness. The soft silver cloud which writhes innocently on the crest of Vesuvius, rests there without intermission; but the fury which lays cities in sepulchres of lava bursts forth only after intervals of centuries; and the still fiercer indignation of the greater volcanoes, which make half the globe vibrate with earthquake, and shrivels up whole kingdoms with flame, is recorded only in dim distances of history: so that it is not irrational to admit that there may yet be powers dormant, not destroyed, beneath the apparently calm surface of the earth, whose date of rest is the endurance of the human race, and whose date of action must be that of its doom. But whether such colossal agencies are indeed in the existing order of things ornot, still the effective truth, for us, is one and the same. The earth, as a tormented and trembling ball, may have rolled in space for myriads of ages before humanity was formed from its dust; and as a devastated ruin it may continue to roll, when all that dust shall again have been mingled with ashes that never were warmed by life, or polluted by sin. But for us the intelligible and substantial fact is that the earth has been brought, by forces we know not of, into a form fitted for our habitation: on that form a gradual, but destructive, change is continually taking place, and the course of that change points clearly to a period when it will no more be fitted for the dwelling-place of men.
§ 6. It is, therefore, not so much what these forms of the earth actually are, as what they are continually becoming, that we have to observe; nor is it possible thus to observe them without an instinctive reference to the first state out of which they have been brought. The existing torrent has dug its bed a thousand feet deep. But in what form was the mountain originally raised which gave that torrent its track and power? The existing precipice is wrought into towers and bastions by the perpetual fall of its fragments. In what form did it stand before a single fragment fell?
Yet to such questions, continually suggesting themselves, it is never possible to give a complete answer. For a certain distance, the past work of existing forces can be traced; but there gradually the mist gathers, and the footsteps of more gigantic agencies are traceable in the darkness; and still, as we endeavor to penetrate farther and farther into departed time, the thunder of the Almighty power sounds louder and louder; and the clouds gather broader and more fearfully, until at last the Sinai of the world is seen altogether upon a smoke, and the fence of its foot is reached, which none can break through.
§ 7. If, therefore, we venture to advance towards the spot where the cloud first comes down, it is rather with the purpose of fully pointing out that there is a cloud, than of entering into it. It is well to have been fully convinced of the existence of the mystery, in an age far too apt to suppose that everything which is visible is explicable, and everything that is present, eternal. But besides ascertaining the existence of this mystery, we shall perhaps be able to form some new conjectures respectingthe facts of mountain aspects in the past ages. Not respecting the processes or powers to which the hills owe their origin, but respecting the aspect they first assumed.
§ 8. For it is evident that, through all their ruin, some traces must still exist of the original contours. The directions in which the mass gives way must have been dictated by the disposition of its ancient sides; and the currents of the streams that wear its flanks must still, in great part, follow the course of the primal valleys. So that, in the actual form of any mountain peak, there must usually be traceable the shadow or skeleton of its former self; like the obscure indications of the first frame of a war-worn tower, preserved, in some places, under the heap of its ruins, in others to be restored in imagination from the thin remnants of its tottering shell; while here and there, in some sheltered spot, a few unfallen stones retain their Gothic sculpture, and a few touches of the chisel, or stains of color, inform us of the whole mind and perfect skill of the old designer. With this great difference, nevertheless, that in the human architecture the builder did not calculate upon ruin, nor appoint the course of impendent desolation; but that in the hand of the great Architect of the mountains, time and decay are as much the instruments of His purpose as the forces by which He first led forth the troops of hills in leaping flocks:—the lightning and the torrent, and the wasting and weariness of innumerable ages, all bear their part in the working out of one consistent plan; and the Builder of the temple for ever stands beside His work, appointing the stone that is to fall, and the pillar that is to be abased, and guiding all the seeming wildness of chance and change, into ordained splendors and foreseen harmonies.
§ 9. Mountain masses, then, considered with respect to their first raising and first sculpture, may be conveniently divided into two great groups; namely, those made up of beds or layers, commonly called stratified; and those made of more or less united substance, called unstratified. The former are nearly always composed of coherent rocks, the latter of crystallines; and the former almost always occupy the outside, the latter the centre of mountain chains. It signifies, therefore, very little whether we distinguish the groups by calling one stratified andthe other unstratified, or one "coherent" and the other "crystalline," or one "lateral" and the other "central." But as this last distinction in position seems to have more influence on their forms than either of the others, it is, perhaps, best, when we are examining them in connection with art, that this should be thoroughly kept in mind; and therefore we will consider the first group under the title of "lateral ranges," and the second under that of "central peaks."
§ 10. Thelateral ranges, which we are first to examine, are, for the most part, broad tabular masses of sandstone, limestone, or whatever their material may be,—tiltedslightly up over large spaces (several or many miles square), and forming precipices with their exposed edges, as a book resting obliquely on another book forms miniature precipices with its back and sides. The book is a tolerably accurate representation of the mountain in substance, as well as in external aspect; nearly all these tabular masses of rock being composed of a multitude of thinner beds or layers, as the thickness of the book is made up of its leaves; while every one of the mountain leaves is usually written over, though in dim characters, like those of a faded manuscript, with history of departed ages.
"How were these mountain volumes raised, and how are they supported?" are the natural questions following such a statement.
And the only answer is: "Behold the cloud."
No eye has ever seen one of these raised on a large scale; no investigation has brought completely to light the conditions under which the materials which support them were prepared. This only is the simple fact, that theyareraised into such sloping positions; generally several resting one upon another, like a row of books fallen down (Fig. 8); the last book being usually propped by a piece of formless compact crystalline rock, represented by the piece of crumpled paper ata.
§ 11. It is another simple fact that this arrangement is not effected in an orderly and serene manner; but that the books, if they were ever neatly bound, have been fearfully torn to pieces and dog's-eared in the course of their elevation; sometimes torn leaf from leaf, but more commonly rent across, as if the paper had been wet and soft: or, to leave the book similitude, which is becoming inconvenient, the beds seem to have been in the consistence of a paste, more or less dry; in some places brittle, and breaking, like a cake, fairly across; in others moist and tough, and tearing like dough, or bending like hot iron; and, in others, crushed and shivering into dust, like unannealed glass. And in these various states they are either bent or broken, or shivered, as the case may be, into fragments of various shapes, which are usually tossed one on top of another, as above described; but, of course, under such circumstances, presenting, not the uniform edges of the books, but jagged edges, as inFig. 9.
§ 12. Do not let it be said that I am passing my prescribed limits, and that I have tried to enter the clouds, and am describing operations which have never been witnessed. I describe facts or semblances, not operations. I say "seemto have been," not "have been." I say "arebent;" I do not say "have beenbent." Most travellers must remember the entrance to the valley of Cluse, from the plain of Bonneville, on the road from Geneva to Chamouni. They remember that immediately after entering it they find a great precipice on their left, not less than two thousand feet in perpendicular height. That precipice is formed by beds of limestone bent like a rainbow, as inFig. 10. Their edges constitute the cliff; the flat arch which they form with their backs is covered with pine forests and meadows, extendingfor three or four leagues in the direction of Sixt. Whether the whole mountain was called out of nothing into the form it possesses, or created first in the form of a level mass, and then actually bent and broken by external force, is quite irrelevant to our present purpose; but it is impossible to describe its form without appearing to imply the latter alternative; and all the distinct evidence which can be obtained upon the subject points to such a conclusion, although there are certain features in such mountains which, up to the present time, have rendered all positive conclusion impossible, not because they contradict the theories in question, but because they are utterly inexplicable on any theory whatever.
§ 13. We return then to ourFig. 9, representing beds whichappearto have been broken short off at the edges. "If they ever were actually broken," the reader asks, "what could have become of the bits?" Sometimes they seem to have been lost, carried away no one knows where. Sometimes they are really found in scattered fragments or dust in the neighborhood. Sometimes the mountain is simply broken in two, and the pieces correspond to each other, only leaving a valley between; but more frequently one half slips down, or the other is pushed up. In such cases, the coincidence of part with part is sometimes so exact, that half of a broken pebble has been found on one side, and the other half five or six hundred feet below, on the other.
§ 14. The beds, however, which are to form mountains of any eminence are seldom divided in this gentle way. If brittle, one would think they had been broken as a captain's biscuit breaks, leaving sharp and ragged edges; and if tough, they appear to have been torn asunder very much like a piece of new cheese.
The beds which present the most definite appearances of abrupt fracture, are those of that grey or black limestone above described (Chap. x. § 4), formed into a number of thin layers or leaves, commonly separated by filmy spreadings of calcareous sand, hard when dry, but easily softened by moisture; the whole, considered as a mass, easily friable, though particular beds may be very thick and hard. Imagine a layer of such substance, three or four thousand feet thick, broken with a sharp crash through the middle, and one piece of it thrown up as inFig. 11. It is evident that the first result of such a shock would be a complete shattering of the consistence of the broken edges, and that these would fall, some on the instant, and others tottering and crumbling away from time to time, until the cliff had got in some degree settled into a tenable form. The fallen fragments would lie in a confused heap at the bottom, hiding perhaps one half of its height, as inFig. 12; the top of it, wrought into somewhat less ragged shape, would thenceforth submit itself only to the gradual influences of time and storm.
I do not say that this operation has actually taken place. I merely say that such cliffs do in multitudesexistin the form shown atFig. 12, or, more properly speaking, in that form modifiedby agencies in visible operation, whose work can be traced upon them, touch by touch. But the condition atFig. 12is the first rough blocking out of their form, the primal state in which they demonstrably were, some thousands of years ago, but beyond which no human reason can trace them without danger of error. The cloud fastens upon them there.
§ 15. It is rare, however, that such a cliff as that represented inFig. 12can maintain itself long in such a contour. Usually it moulders gradually away into a steep mound or bank; and the larger number of bold cliffs are composed of far more solid rock, which in its general make is quite unshattered and flawless; apparently unaffected, as far as its coherence is concerned, by any shock it may have suffered in being raised to its position, or hewn into its form. Beds occur in the Alps composed of solid coherent limestone (such as that familiar to the English traveller in the cliffs of Matlock and Bristol), 3000 or 4000 feet thick, and broken short off throughout a great part of this thickness, forming nearly50sheer precipices not less than 1500 or 2000 feet in height, after all deduction has been made for slopes of débris at the bottom, and for rounded diminution at the top.
§ 16. The geologist plunges into vague suppositions and fantastic theories in order to account for these cliffs; but, after all that can be dreamed or discovered, they remain in great part inexplicable. If they were interiorly shattered, it would be easy to understand that, in their hardened condition, they had been broken violently asunder; but it is not easy to conceive a firm cliff of limestone broken through a thickness of 2000 feet without showing a crack in any other part of it. If they were divided in a soft state, like that of paste, it is still less easy to understand how any such soft material could maintain itself, till it dried, in the form of a cliff so enormous and so ponderous: it must have flowed down from the top, or squeezed itself out in bulging protuberance at the base. But it has done neither; and we are left to choose between the suppositions that the mountain was created in a form approximating to that which it now wears, or that the shock which produced it wasso violent and irresistible, as to do its work neatly in an instant, and cause no flaws to the rock except in the actual line of fracture. The force must have been analogous either to the light and sharp blow of the hammer with which one breaks a stone into two pieces as it lies in the hand, or the parting caused by settlement under great weight, like the cracks through the brickwork of a modern ill-built house. And yet the very beds which seem at the time they were broken to have possessed this firmness of consistency, are also bent throughout their whole body into waves, apparently following the action of the force that fractured them, like waves of sea under the wind. Truly the cloud lies darkly upon us here!
§ 17. And it renders these precipices more remarkable that there is in them no principle of compensation against destructive influences. They are not cloven back continually into new cliffs, as our chalk shores are by the sea; otherwise, one might attribute their first existence to the force of streams. But, on the contrary, the action of years upon them is now always one of deterioration. The increasing heap of fallen fragments conceals more and more of their base, and the wearing of the rain lowers the height and softens the sternness of their brows, so that a great part of their terror has evidently been subdued by time; and the farther we endeavor to penetrate their history, the more mysterious are the forms we are required to explain.
§ 18. Hitherto, however, for the sake of clearness, we have spoken of hills as if they were composed of a single mass orThe three great representative forms of stratified mountains.volume of rock. It is very seldom that they are so. Two or three layers are usually raised at once, with certain general results on mountain form, which it is next necessary to examine.
1st. Suppose a series of beds raised in the conditiona,Fig. 13, the lowest soft, the uppermost compact; it is evident that the lower beds would rapidly crumble away, and the compact1. Wall above slope.mass above break for want of support, until the rocks beneath had reached a slope at which they could securely sustain themselves, as well as the weight of wall above, thus bringing the hill into the outlineb.
2d. If, on the other hand, the hill were originally raised as atc, the softest beds being at the top, these would crumble into their smooth slope without affecting the outline of the mass below,2. Slope above wall.and the hill would assume the formd, large masses of débris being in either of these two cases accumulated at the foot of the slope, or of the cliff. These first ruins might, by subsequent changes, be variously engulfed, carried away, or covered over, so as to leave nothing visible, or at least nothing notable, but the great cliff with its slope above or below it. Without insisting on the evidences or probabilities of such construction, it is sufficient to state that mountains of the two types,bandd, are exceedingly common in all parts of the world; and though of course confused with others, and themselves always more or less imperfectly developed, yet they are, on the whole, singularly definite as classes of hills, examples of which can hardly but remain clearly impressed on the mind of every traveller. Of the first,b, Salisbury Crags, near Edinburgh, is a nearly perfect instance, though on a diminutive scale. The cliffs of Lauterbrunnen, in the Oberland, are almost without exception formed on the typed.
3d. When the elevated mass, instead of consisting merely of two great divisions, includes alternately hard and soft beds, as ata,Fig. 14, the vertical cliffs and inclined banks alternate with3. Slope and wall alternately.each other, and the mountain rises on a series of steps, with receding slopes of turf or débris on theledge of each, as atb. At the head of the valley of Sixt, in Savoy, huge masses of mountain connected with the Buet are thus constructed: their slopes are quite smooth, and composed of good pasture land, and the cliffs in many places literally vertical. In the summer the peasants make hay on the inclined pastures; and the hay is "carried" by merely binding the haycocks tight and rolling them down the slope and over the cliff, when I have heard them fall to the bank below, a height of from five to eight hundred feet, with a sound like the distant report of a heavy piece of artillery.
§ 19. The next point of importance in these beds is the curvature, to which, as well as to fracture, they seem to have been subjected. This curvature is not to be confounded with that rippling or undulating character of every portion of the slaty crystalline rocks above described. I am now speaking of all kinds of rocks indifferently;—not of their appearance in small pieces, but of their great contours in masses, thousands of feet thick. And it is almost universally true of these masses that they do not merely lie in flat superposition one over another, as the books inFig. 8; but they lie inwaves, more or less vast and sweeping according to the scale of the country, as inFig. 15, where the distance from one side of the figure to the other is supposed to be four or five leagues.
§ 20. Now, observe, if the precipices which we have just been describing had been broken when their substance was in a hard state, there appears no reason why any connexion should be apparent between the energy ofundulationand thesebrokenrocks. If the continuous waves were caused by convulsive movements of the earth's surface while its substance was pliable, and were left in repose for so long a period as to become perfectly hard before they were broken into cliffs, there seems no reason why the second series of shocks should so closely haveconfined itself to the locality which had suffered the first, that the most abrupt precipices should always be associated with the wildest waves. We might have expected that sometimes we should have had noble cliffs raised where the waves had been slight; and sometimes low and slight fractures where the waves had been violent. But this is not so. The contortions and fractures bear always such relation to each other as appears positively to imply contemporaneous formation. Through all the lowland districts of the world the average contour of the waves of rock is somewhat as represented inFig. 16a, and the little cliffs or hills formed at the edges of the beds (whether by fracture, or, as oftener happens in such countries, by gradual washing away under the surge of ancient seas) are no higher, in proportion to the extent of surface, than the little steps seen in the centre of the figure. Such is the nature, and such the scale, of the ranges of hills which form our own downs and wolds, and the French coteaux beside their winding rivers. But as we approach the hill countries, the undulation becomes moremarked, and the crags more bold; so that almost any portion of such mountain ranges as the Jura or the Vosges will present itself under conditions such as those atb, the precipices at the edges being bolder in exact proportion to the violence of wave. And, finally, in the central and noblest chains the undulation becomes literally contortion; the beds occur in such positions as those atc, and the precipices are bold and terrific in exact proportion to this exaggerated and tremendous contortion.
§ 21. These facts appear to be just as contrary to the supposition of the mountains having been formed while the rocks were hard, as the considerations adduced in § 15 are to that of their being formed while they were soft. And I believe the more the reader revolves the subject in his thoughts, and the more opportunities he has of examining the existing facts, the less explicable those facts will become to him, and the more reverent will be his acknowledgment of the presence of the cloud.
For, as he examines more clearly the structure of the great mountain ranges, he will find that though invariably the boldest forms are associated with the most violent contortions, they sometimesfollowthe contortions, and sometimes appear entirely independent of them. For instance, in crossing the pass of the Tête Noire, if the traveller defers his journey till near the afternoon, so that from the top of the pass he may see the great limestone mountain in the Valais, called the Dent de Morcles, under the full evening light, he will observe that its peaks are hewn out of a group of contorted beds, as shown in Fig. 4,Plate 29. The wild and irregular zigzag of the beds, which traverse the face of the cliff with the irregularity of a flash of lightning, has apparently not the slightest influence on the outline of the peak. It has been carved out of the mass, with no reference whatever to the interior structure. In like manner, as we shall see hereafter, the most wonderful peak in the whole range of the Alps seems to have been cut out of a series of nearly horizontal beds, as a square pillar of hay is cut out of a half-consumed haystack. And yet, on the other hand, we meet perpetually with instances in which the curves of the beds have in great part directed the shape of the whole mass of mountain. The gorge which leads from the village of Ardon, in the Valais, up to the root of the Diablerets, runs between two ranges oflimestone hills, of which the rude contour is given inFig. 17, page 154. The great slope seen on the left, rising about seven thousand feet above the ravine, is nothing but the back of one sheet of limestone, whose broken edge forms the first cliff at the top, a height of about six hundred feet, the second cliff being the edge of another bed emergent beneath it, and the slope beyond, the surface of a third. These beds of limestone all descend at a uniform inclination into the gorge, where they are snapped short off, the torrent cutting its way along the cleft, while the beds rise on the other side in a huge contorted wave, forming the ridge of mountains on the right,—a chain about seven miles in length, and from five thousand to six thousand feet in height. The actual order of the beds is seen inFig. 18, and it is one of the boldest and clearest examples of the form of mountains being correspondent to the curves of beds which I have ever seen; it also exhibits a condition of the summits which is of constant occurrence in stratified hills, and peculiarly important as giving rise to the serrated structure, rendered classical by the Spaniards in their universal term for mountain ridges, Sierra, and obtaining for one of the most important members of the Comasque chain of Alps its well known Italian name—Il Resegone. Such mountains are not merely successions of irregular peaks, more or less resembling the edge of a much-hacked sword; they are orderly successions of teeth set in one direction, closely resembling those of a somewhat overworn saw, and nearly always produced by successive beds emerging one from beneath the other.
§ 22. In all such cases there is an infinitely greater difficulty in accounting for the forms than in explaining the fracture of a single bed. How, and when, and where, were the other portions carried away? Was each bed once continuous over a much larger space from the point where its edge is now broken off, or have such beds slipped back into some gulf behind them? It is very easy for geologists to speak generally of elevation and convulsion, but very difficult to explain what sort of convulsion it could be which passed forward from the edge of one bed to the edge of another, and broke the required portion off each without disturbing the rest. Try the experiment in the simplest way: put half a dozen of hard captain's biscuits in a slopingposition on a table, and then try, as they lie, to break the edge of each, one by one, without disturbing the rest. At least, you will have to raise the edge before you can break it; to put your hand underneath, between it and the next biscuit, before you can get any purchase on it. What force was it that put its fingers between one bed of limestone 600 feet thick and the next beneath? If you try to break the biscuits by a blow from above, observe the necessary force of your blow, and then conceive, if you can, the sort of hammer that was required to break the 600 feet of rock through in the same way. But, also, you will, ten to one, break two biscuits at the same time. Now, in these serrated formations, two biscuits areneverbroken at the same time. There is no appearance of the slightest jar having taken place affecting the bed beneath. If there be, a huge cliff or gorge is formed at that spot, not a sierra. Thus, inFig. 18, the beds are affected throughout their united body by the shock which formed the ravine ata; but they are broken, one by one, into the cliffs atbandc. Sometimes one is tempted to think that they must have been slipped back, one from off the other; but there is never any appearance of friction having taken place on their exposed surfaces; in the plurality of instances their continuance or rise from their roots in waves (seeFig. 16above) renders the thing utterly impossible; and in the few instances which have been known of such action actually takingplace(which have always been on a small scale), the sliding bed has been torn into a thousand fragments almost as soon as it began to move.51
§ 23. And, finally, supposing a force found capable of breaking these beds in the manner required, what force was it that carried the fragments away? How were the gigantic fields of shattered marble conveyed from the ledges which were to remain exposed? No signs of violence are found on these ledges; what marks there are, the rain and natural decay have softly traced through a long series of years. Those very time-marks may have indeed effaced mere superficial appearances of convulsion; but could they have effaced all evidence of the action ofsuch floods as would have been necessary to carry bodily away the whole ruin of a block of marble leagues in length and breadth, and a quarter of a mile thick? Ponder over the intense marvellousness of this. The bed atc(Fig. 18) must first be broken through the midst of it into a sharp precipice, without at all disturbing it elsewhere; and then all of it beyondcis to be broken up, and carried perfectly away, without disturbing or wearing down the face of the cliff atc.
And yet no trace of the means by which all this was effected is left. The rock stands forth in its white and rugged mystery, as if its peak had been born out of the blue sky. The strength that raised it, and the sea that wrought upon it, have passed away, and left no sign; and we have no words wherein to describe their departure, no thoughts to form about their action, than those of the perpetual and unsatisfied interrogation,—
"What ailed thee, O thou sea, that thou fleddest?And ye mountains, that ye skipped like lambs?"
49How far, is another question. The sand which the stream brings from the bottom of one eddy in its course, it throws down in the next; all that isprovedby the above trial is, that so many tons of material are annually carried down by it a certain number of feet.50Nearly; that is to say, not quite vertical. Of the degree of steepness, we shall have more to say hereafter.51The Rossberg fall, compared to the convulsions which seem to have taken place in the higher Alps, is like the slip of a paving stone compared to the fall of a tower.
49How far, is another question. The sand which the stream brings from the bottom of one eddy in its course, it throws down in the next; all that isprovedby the above trial is, that so many tons of material are annually carried down by it a certain number of feet.
50Nearly; that is to say, not quite vertical. Of the degree of steepness, we shall have more to say hereafter.
51The Rossberg fall, compared to the convulsions which seem to have taken place in the higher Alps, is like the slip of a paving stone compared to the fall of a tower.
§ 1.In the20th paragraph of the last chapter, it was noticed that ordinarily the most irregular contortions or fractures of beds of rock were found in the districts of most elevated hills, the contortion or fracture thus appearing to be produced at the moment of elevation. It has also previously been stated that the hardness and crystalline structure of the material increased with the mountainous character of the ground; so that we find as almost invariably correlative, thehardnessof the rock, itsdistortion, and itsheight; and, in like manner itssoftness,regularityofposition, andlowness. Thus, the line of beds in an English range of down, composed of soft chalk which crumbles beneath the fingers, will be as low and continuous as inaofFig. 16(p. 151); the beds in the Jura mountains, composed of firm limestone, which needs a heavy hammer stroke to break it, will be as high and wavy as atb; and the ranges of Alps, composed of slaty crystallines, yielding only to steel wedges or to gunpowder, will be as lofty and as wild in structure as atc. Without this beneficent connection of hardness of material with height, mountain ranges either could not have existed, or would not have been habitable. In their present magnificent form, they could not have existed; and whatever their forms, the frequent falls and crumblings away, which are of little consequence in the low crags of Hastings, Dover, or Lyme, would have been fatal to the population of the valleys beneath, when they took place from heights of eight or ten thousand feet.
§ 2. But this hardening of the material would not have been sufficient, by itself, to secure the safety of the inhabitants. Unless the reader has been already familiarized with geological facts, he must surely have been struck by the prominence ofthebeddedstructure in all the instances of mountain form given in the preceding chapter; and must have asked himself, Why are mountains always built in this masonry-like way, rather than in compact masses? Now, it is true that according to present geological theories, the bedded structure was a necessary consequence of the mode in which the materials were accumulated; but it is not less true that this bedded structure is now the principal means of securing the stability of the mass, and is to be regarded as a beneficent appointment, with such special view. That structure compels each mountain to assume the safest contour of which under the given circumstances of upheaval it is capable. If it were all composed of an amorphous mass of stone as atA,Fig. 19, a crack beginning from the top, as atxinA, might gradually extend downwards in the directionxyinB, until the whole mass, indicated by the shade, separated itself and fell. But when the whole mountain is arranged in beds, as atC, the crack beginning at the top stops in the uppermost bed, or, if it extends to the next, it will be in a different place, and the detached blocks, marked by the shaded portions, are of course still as secure in their positions as before the crack took place. If, indeed, the beds sloped towards the precipice, as atD, the danger would be greater; but if the reader looks to any of the examples of mountain form hitherto given, he will find that the universal tendency of the modes of elevation is tocause the beds to slopeawayfrom the precipice, and to build the whole mountain in the formC, which affords the utmost possible degree of security. Nearly all the mountains which rise immediately above thickly peopled districts, though they may appear to be thrown into isolated peaks, are in reality nothing more than flattish ranks of rock, terminated by walls of cliff, of this perfectly safe kind; and it will be part of our task in the succeeding chapter to examine at some length the modes in which sublime and threatening forms are almost deceptively assumed by arrangements of mountain which are in themselves thus simple and secure.
§ 3. It, however, fell within the purpose of the Great Builder to give, in the highest peaks of mountains, examples of form more strange and majestic than any which could be attained by structures so beneficently adapted to the welfare of the human race. And the admission of other modes of elevation, more terrific and less secure, takes place exactly in proportion to the increasing presence of such conditions in the locality as shall render it on other grounds unlikely to be inhabited, or incapable of being so. Where the soil is rich and the climate soft, the hills are low and safe;52as the ground becomes poorer and the air keener, they rise into forms of more peril and pride; and their utmost terror is shown only where their fragments fall on trackless ice, and the thunder of their ruin can be heard but by the ibex and the eagle.
§ 4. The safety of the lower mountains depends, as has just been observed, on their tendency to divide themselves into beds. But it will easily be understood that, together with security, such a structure involves some monotony of aspect; and that the possibility of a rent like that indicated in the last figure, extending itself without a check, so as to detach some vast portion of the mountain at once, would be a means of obtaining accidental forms of far greater awfulness. We find, accordingly, that the bedded structure is departed from in the central peaks; thatthey are in reality gifted with this power, or, if we choose so to regard it, affected with this weakness, of rending downwards throughout into vertical sheets; and that to this end they are usually composed of that structureless and massive rock which we have characterized by the term "compact crystalline."
§ 5. This, indeed, is not universal. It happens sometimes that toward the centre of great hill ranges ordinary stratified rocks of the coherent groups are hardened into more compact strength than is usual with them; and out of the hardened mass a peak, or range of peaks, is cut as if out of a single block. Thus the well known Dent du Midi of Bex, a mountain of peculiar interest to the English travellers who crowd the various inns and pensions which now glitter along the shores of the Lake of Geneva at Vevay, Clarens, and Montreux, is cut out of horizontal beds of rock which are traceable in the evening light by their dark and light lines along its sides, like courses of masonry; the real form of the mountain being that of the ridge of a steep house-roof, jagged and broken at the top, so that, seen from near St. Maurice, the extremity of the ridge appears a sharp pyramid. The Dent de Morcles, opposite the Dent du Midi, has been already noticed, and is figured inPlate 29, Fig. 4. In like manner, the Matterhorn is cut out of a block of nearly horizontal beds of gneiss. But in all these cases the materials are so hardened and knit together that to all intents and purposes they form one solid mass, and when the forms are to be of the boldest character possible, this solid mass is unstratified, and of compact crystalline rock.
§ 6. In looking from Geneva in the morning light, when Mont Blanc and its companion hills are seen dark against the dawn, almost every traveller must have been struck by the notable range of jagged peaks which bound the horizon immediately to the north-east of Mont Blanc. In ordinary weather they appear a single chain, but if any clouds or mists happen to float into the heart of the group, it divides itself into two ranges, lower and higher, as in Fig. 1,Plate 29, of which the uppermost and more distant chain is the real crest of the Alps, and the lower and darker line is composed of subordinate peaks which form the south side of the valley of Chamouni, and are therefore ordinarily known as the "Aiguilles of Chamouni."
Though separated by some eight or nine miles of actual distance, the two ranges are part of one and the same system of rock. They are both of them most notable examples of the structure of the compact crystalline peaks, and their jagged and spiry outlines are rendered still more remarkable in any view obtained of them in the immediate neighborhood of Geneva, by their rising, as in the figure, over two long slopes of comparatively flattish mountain. The highest of these is the back of a stratified limestone range, distant about twenty-five miles, whose precipitous extremity, nodding over the little village of St. Martin's, is well known under the name of the Aiguille de Varens. The nearer line is the edge of another limestone mountain, called the Petit Salève, within five miles of Geneva. And thus we have two ranges of the crystalline rocks opposed to two ranges of the coherents, both having their distinctive characters, the one of vertical fracture, the other of level continuousness, developed on an enormous scale. I am aware of no other view in Europe where the essential characteristics of the two formations are so closely and graphically displayed.
§ 7. Nor can I imagine any person thoughtfully regarding the more distant range, without feeling his curiosity strongly excited as to the method of its first sculpture. That long banks and fields of rock should be raised aslope, and break at their edges into cliffs, however mysterious the details of the operation may be, is yet conceivable in the main circumstances without any great effort of imagination. But the carving of those great obelisks and spires out of an infinitely harder rock; the sculpture of all the fretted pinnacles on the inaccessible and calm elevation of that great cathedral,—how and when was this wrought? It is necessary, before the extent and difficulty of such a question can be felt, to explain more fully the scale and character of the peaks under consideration.
§ 8. The valley of Chamouni, largely viewed, and irrespectively of minor ravines and irregularities, is nothing more than a deep trench, dug between two ranges of nearly continuous mountains,—dug with a straightness and evenness which render its scenery, in some respects, more monotonous than that of any other Alpine valley. On each side it is bordered by banks of turf, darkened with pine forest, rising at an even slope to aheight of about 3000 feet, so that it may best be imagined as a kind of dry moat, which, if cut across, would be of the form typically shown inFig. 20; the sloping bank on each side being about 3000 feet high, or the moat about three fifths of a mile in vertical depth. Then, on the top of the bank, on each side, and a little way back from the edge of the moat, rise the ranges of the great mountains, in the form of shattered crests and pyramids of barren rock sprinkled with snow. Those on the south side of the valley rise another 3000 feet above the bank on which they stand, so that each of the masses superadded inFig. 21may best be described as a sort of Egyptian pyramid,53of the height of Snowden or Ben Lomond, hewn out of solid rock, and set on the shoulder of the great bank which borders the valley. Then the Mont Blanc, a higher and heavier cluster of such summits, loaded with deep snow, terminates the range. Glaciers of greater or less extent descend between the pyramids of rock; and one, supplied from their largest recesses, even runs down the bank into the valley.Fig. 2254rudely represents the real contours of the mountains, includingMont Blanc itself, on its south side. The range of peaks,b,p, m, is that already spoken of, known as the "Aiguilles of Chamouni." They form but a very small portion of a great crowd of similar, and, for the most part, larger peaks which constitute the chain of Mont Blanc, and which receive from the Savoyards the name of Aiguilles, or needles, in consequence of their peculiarly sharp summits. The forms of these Aiguilles, wonderful enough in themselves, are, nevertheless, perpetually exaggerated both by the imagination of the traveller, and by theartists whose delineations of them find most frank acceptance. Fig. 1 inPlate 30is faithfully copied from the representation given of one of these mountains in a plate lately published at Geneva. Fig. 2 in the same plate is a true outline of the mountain itself. Of the exaggerations in the other I shall have more to say presently; meantime, I refer to it merely as a proof that I am not myself exaggerating, in givingFig. 22as showing the general characters of these peaks.
§ 9. This, then, is the problem to be considered,—How mountains of such rugged and precipitous outline, and at the least 3000 feet in height, were originally carved out of the hardest rocks, and set in their present position on the top of the green and sloping bank which sustains them.
"By mere accident," the reader replies. "The uniform bank might as easily have been the highest, and the broken granite peaks have risen from its sides, or at the bottom of it. It is merely the chance formation of the valley of Chamouni."
Nay; not so. Although, as if to bring the problem more clearly before the thoughts of men, by marking the structure most where the scenery is most attractive, the formation is more distinct at Chamouni than anywhere else in the Alpine chain; yet the general condition of a rounded bank sustaining jagged or pyramidal peaks is more or less traceable throughout the whole district of the great mountains. The most celebrated spot, next to the valley of Chamouni, is the centre of the Bernese Oberland; and it will be remembered by all travellers that in its principal valley, that of Grindelwald, not only does the summit of the Wetterhorn consist of a sharp pyramid raised on the advanced shoulder of a great promontory, but the two most notable summits of the Bernese Alps, the Schreckhorn and Finsteraarhorn, cannot be seen from the valley at all, being thrown far back upon an elevated plateau, of which only the advanced head or shoulder, under the name of the Mettenberg, can be seen from the village. The real summits, consisting in each case of a ridge starting steeply from this elevated plateau, as if by a new impulse of angry or ambitious mountain temper, can only be seen by ascending a considerable height upon the flank of the opposite mass of the Faulhorn.
§ 10. And this is, if possible, still more notably and provokinglythe case with the great peaks of the chain of Alps between Monte Rosa and Mont Blanc. It will be seen, by a glance at any map of Switzerland, that the district which forms the canton Valais is, in reality, nothing but a ravine sixty miles long, between that central chain and the Alps of the cantons Fribourg and Berne. This ravine is also, in its general structure, merely a deeper and widermoatthan that already described as forming the valley of Chamouni. It lies, in the same manner, between twobanksof mountain; and the principal peaks are precisely in the same manner set back upon the tops of these banks; and so provokingly far back, that throughout the whole length of the valley not one of the summits of the chief chain can be seen from it. That usually pointed out to travellers as Monte Rosa is a subordinate, though still very colossal mass, called the Montagne de Saas; and this is the only peak of great size discoverable from the valley throughout its extent; one or two glimpses of the snows, not at any eminent point, being caught through the entrances of the lateral valleys of Evolena, &c.
§ 11. Nor is this merely the consequence of the greatdistanceof the central ridge. It would be intelligible enough that the mountains should rise gradually higher and higher towards the middle of the chain, so that the summit atain the upper diagram ofFig. 23should be concealed by the intermediate eminencesb,c, from the valley atd. But this is not, by any means, the manner in which the concealment is effected. The great peaks stand, as atain the lower diagram, jagged, sharp, andsuddenly starting out of a comparatively tame mass of elevated land, through which the trench of the valley of the Rhone is cut, as atc. The subdivision of the bank atbby thousands of ravines, and its rise, here and there, into more or less notable summits, conceal the real fact of the structure from a casual observer. But the longer I stayed among the Alps, and the more closely I examined them, the more I was struck by the one broad fact of their being a vast Alpine plateau, or mass of elevated land, upon which nearly all the highest peaks stood like children set upon a table, removed, in most cases, far back from the edge of the plateau, as if for fear of their falling. And the most majestic scenes in the Alps are produced, not so much by any violation of this law, as by one of the great peaks having apparently walked to the edge of the table to look over, and thus showing itself suddenly above the valley in its full height. This is the case with the Wetterhorn and Eiger at Grindelwald, and with the Grande Jorasse, above the Col de Ferret. But the raised bank or table is always intelligibly in existence, even in these apparently exceptional cases; and, for the most part, the great peaks are not allowed to come to the edge of it, but remain like the keeps of castles far withdrawn, surrounded, league beyond league, by comparatively level fields of mountain, over which the lapping sheets of glacier writhe and flow, foaming about the feet of the dark central crests like the surf of an enormous sea-breaker hurled over a rounded rock, and islanding some fragment of it in the midst. And the result of this arrangement is a kind of division of the whole of Switzerland into an upper and lower mountain-world; the lower world consisting of rich valleys bordered by steep, but easily accessible, wooded banks of mountain, more or less divided by ravines, through which glimpses are caught of the higher Alps; the upper world, reached after the first steep banks, of 3000 or 4000 feet in height, have been surmounted, consisting of comparatively level but most desolate tracts of moor and rock, half covered by glacier, and stretching to the feet of the true pinnacles of the chain.
§ 12. It can hardly be necessary to point out the perfect wisdom and kindness of this arrangement, as a provision for the safety of the inhabitants of the high mountain regions. If thegreat peaks rose at once from the deepest valleys, every stone which was struck from their pinnacles, and every snow-wreath which slipped from their ledges, would descend at once upon the inhabitable ground, over which no year could pass without recording some calamity of earth-slip or avalanche; while, in the course of their fall, both the stones and the snow would strip the woods from the hill sides, leaving only naked channels of destruction where there are now the sloping meadow and the chestnut glade. Besides this, the masses of snow, cast down at once into the warmer air, would all melt rapidly in the spring, causing furious inundation of every great river for a month or six weeks. The snow being then all thawed, except what lay upon the highest peaks in regions of nearly perpetual frost, the rivers would be supplied, during the summer, only by fountains, and the feeble tricklings on sunny days from the high snows. The Rhone under such circumstances would hardly be larger at Lyons than the Severn at Shrewsbury, and many Swiss valleys would be left almost without moisture. All these calamities are prevented by the peculiar Alpine structure which has been described. The broken rocks and the sliding snow of the high peaks, instead of being dashed at once to the vales, are caught upon the desolate shelves or shoulders which everywhere surround the central crests. The soft banks which terminate these shelves, traversed by no falling fragments, clothe themselves with richest wood; while the masses of snow heaped upon the ledge above them, in a climate neither so warm as to thaw them quickly in the spring, nor so cold as to protect them from all the power of the summer sun, either form themselves into glaciers, or remain in slowly wasting fields even to the close of the year,—in either case supplying constant, abundant, and regular streams to the villages and pastures beneath, and, to the rest of Europe, noble and navigable rivers.
§ 13. Now, that such a structure is the best and wisest possible, is, indeed, sufficient reason for its existence; and to many people it may seem useless to question farther respecting its origin. But I can hardly conceive any one standing face to face with one of these towers of central rock, and yet not also asking himself, Is this indeed the actual first work of the Divine Master on which I gaze? Was the great precipice shaped by His finger,as Adam was shaped out of the dust? Were its clefts and ledges carved upon it by its Creator, as the letters were on the Tables of the Law, and was it thus left to bear its eternal testimony to His beneficence among these clouds of heaven? Or is it the descendant of a long race of mountains, existing under appointed laws of birth and endurance, death and decrepitude?
§ 14. There can be no doubt as to the answer. The rock itself answers audibly by the murmur of some falling stone or rending pinnacle. It isnotas it was once. Those waste leagues around its feet are loaded with the wrecks of what it was. On these, perhaps, of all mountains, the characters of decay are written most clearly; around these are spread most gloomily the memorials of their pride, and the signs of their humiliation.
"What then were they once?"
The only answer is yet again,—"Behold the cloud."
Their form, as far as human vision can trace it, is one of eternal decay. No retrospection can raise them out of their ruins, or withdraw them beyond the law of their perpetual fate. Existing science may be challenged to form, with the faintest color of probability, any conception of the original aspect of a crystalline mountain; it cannot be followed in its elevation, nor traced in its connection with its fellows. No eyes ever "saw its substance, yet being imperfect;" its history is a monotone of endurance and destruction: all that we can certainly know of it, is that it was once greater than it is now, and it only gathers vastness, and still gathers, as it fades into the abyss of the unknown.
§ 15. Yet this one piece of certain evidence ought not to be altogether unpursued; and while, with all humility, we shrink from endeavoring to theorize respecting processes which are concealed, we ought not to refuse to follow, as far as it will lead us, the course of thought which seems marked out by conspicuous and consistent phenomena. Exactly as the form of the lower mountains seems to have been produced by certain raisings and bendings of their formerly level beds, so the form of these higher mountains seems to have been produced by certain breakings away from their former elevated mass. If the process appears in either case doubtful, it is less so with respect to thehigher hills. We may not easily believe that the steep limestone cliffs on one side of a valley, now apparently secure and steadfast, ever were united with the cliffs on the other side; but we cannot hesitate to admit that the peak which we see shedding its flakes of granite, on all sides of it, as a fading rose lets fall its leaves, was once larger than it is, and owes the present characters of its forms chiefly to the modes of its diminution.
§ 16. Holding fast this clue, we have next to take into consideration another fact of not less importance,—that over the whole of the rounded banks of lower mountain, wherever they have been in anywise protected from the injuries of time, there are yet visible the tracks of ancient glaciers. I will not here enter into detail respecting the mode in which traces of glaciers are distinguishable. It is enough to state that the footmark, so to speak, of a glacier is just as easily recognizable as the trail of any well-known animal; and that with as much confidence as we should feel in asserting that a horse had passed along a soft road which yet retained the prints of its shoes, it may be concluded that the glaciers of the Alps had once triple or quadruple the extent that they have now; so that not only the banks of inferior mountains were once covered with sheets of ice, but even the great valley of the Rhone itself was the bed of an enormous "Mer de Glace," which extended beyond the Lake of Geneva to the slopes of Jura.55
§ 17. From what has already been noted of glacier action, the reader cannot but be aware that its universal effect is to round and soften the contours of the mountains subjected to it; so that a glacier may be considered as a vast instrument of friction, a white sand-paper, applied slowly but irresistibly to all the roughnesses of the hill which it covers. And this effect is of course greatest when the ice flows fastest, and contains more embedded stones; that is to say, greater towards the lower part of a mountain than near its summit.
Suppose now a chain of mountains raised in any accidental form, only of course highest where the force was greatest,—thatis to say, at the centre of the chain,—and presenting any profile such asa,Fig. 24; terminated, perhaps, by a broken secondary cliff, and the whole covered with a thick bed of glacier, indicated by the spotted space, and moving in the direction of the arrows. As it wears away the mountain, not at all at the top, but always more and more as it descends, it would in process of time reduce the contour of the flank of the hill to the form atb. But at this point the snow would begin to slide from the central peak, and to leave its rocks exposed to the action of the atmosphere. Supposing those rocks disposed to break into vertical sheets, the summit would soon cleave itselfinto such a form as that atx; and the flakes again subdividing and falling, we should have conditions such as aty. Meanwhile the glacier is still doing its work uninterruptedly on the lower bank, bringing the mountain successively into the outlinescandd, in which the formsxandyare substituted consecutively for the original summit. But the level of the whole flank of the mountain being now so much reduced, the glacier has brought itself by its own work into warmer climate, and has wrought out its own destruction. It would gradually be thinned away, and in many places at last vanish, leaving only the barren rounded mountains, and the tongues of ice still supplied from the peaks above.