[Ill.u.s.tration: FIG. 49.]

-- 7. In order to obtain this kind of crest, we first require to have our mountain beds thrown up in the form _a_, Fig. 48. This is not easily done on a large scale, except among the slaty crystallines forming the flanks of the great chains, as in Fig. 29, p. 176. In that figure it will be seen that the beds forming each side of the chain of Mont Blanc are thrown into the required steepness, and therefore, whenever they are broken towards the central mountain, they naturally form the front of a crest, while the torrents and glaciers falling over their longer slopes, carve them into rounded banks towards the valley.

-- 8. But the beauty of a crest or bird's wing consists, in nature, not merely in its curved terminal outline, but in the radiation of the plumes, so that while each a.s.sumes a different curve, every curve shall show a certain harmony of direction with all the others.

We shall have to enter into the examination of this subject at greater length in the 17th chapter; meanwhile, it is sufficient to observe the law in a single example, such as Fig. 49, which is a wing of one of the angels in Durer's woodcut of the Fall of Lucifer.[68] At first sight, the plumes seem disposed with much irregularity, but there is a sense of power and motion in the whole which the reader would find was at once lost by a careless copyist; for it depends on the fact that if we take the princ.i.p.al curves at any points of the wing, and continue them in the lines which they are pursuing at the moment they terminate, these continued lines will all meet in a single point, C. It is this law which gives unity to the wing.

All groups of curves set beside each other depend for their beauty upon the observance of this law;[69] and if, therefore, the mountain crests are to be perfectly beautiful, Nature must contrive to get this element of radiant curvature into them in one way or another. Nor does it, at first sight, appear easy for her to get, I do not say radiant curves, but curves _at all_: for in the aiguilles, she actually bent their beds; but in these slaty crystallines it seems not always convenient to her to bend the beds; and when they are to remain straight, she must obtain the curvature in some other way.

[Ill.u.s.tration: FIG. 50.]

[Ill.u.s.tration: FIG. 51.]

[Ill.u.s.tration: FIG. 52.]

-- 9. One way in which she gets it is curiously simple in itself, but somewhat difficult to explain, unless the reader will be at the pains of making a little model for himself out of paste or clay. Hitherto, observe, we have spoken of these crests as seen at their sides, as a Greek helmet is seen from the side of the wearer. By means presently to be examined, these mountain crests are so shaped that, seen _in front_, or from behind (as a helmet crest is seen in front of or behind the wearer), they present the contour of a sharp ridge, or house gable. Now if the breadth of this ridge at its base remains the same, while its height gradually diminishes from the front of it to the back (as from the top of the crest to the back of the helmet), it necessarily a.s.sumes the form of such a quaint gable roof as that shown in profile in Fig.

50, and in perspective[70] in Fig. 51, in which the gable is steep at the end farthest off, but depressed at the end nearest us; and the rows of tiles, in consequence, though in reality quite straight, appear to radiate as they retire, owing to their different slopes. When a mountain crest is thus formed, and the concave curve of its front is carried into its flanks, each edge of bed a.s.suming this concave curve, and radiating, like the rows of tiles, in perspective at the same time, the whole crest is thrown into the form Fig. 52, which is that of the radiating plume required.

[Ill.u.s.tration: FIG. 53.]

-- 10. It often happens, however, that Nature does not choose to keep the ridge broad at the lower extremity, so as to diminish its steepness. But when this is not so, and the base is narrowed so that the slope of side shall be nearly equal everywhere, she almost always obtains her varied curvature of the plume in another way, by merely turning the crest a little round as it descends. I will not confuse the reader by examining the complicated results of such turning on the inclined lines of the strata; but he can understand, in a moment, its effect on another series of lines, those caused by rivulets of water down the sides of the crest.

These lines are, of course, always, in general tendency, perpendicular.

Let _a_, Fig. 53, be a circular funnel, painted inside with a pattern of vertical lines meeting at the bottom. Suppose these lines to represent the ravines traced by the water. Cut off a portion of the lip of the funnel, as at _b_, to represent the crest side. Cut the edge so as to slope down towards you, and add a slope on the other side. Then give each inner line the concave sweep, and you have your ridge _c_, of the required form, with radiant curvature.

-- 11. A greater s.p.a.ce of such a crest is always seen on its concave than on its convex side (the outside of the funnel); of this other perspective I shall have to speak hereafter; meantime, we had better continue the examination of the proper crest, the _c_ of Fig. 48, in some special instance.

The form is obtained usually in the greatest perfection among the high ridges near the central chain, where the beds of the slaty crystallines are steep and hard. Perhaps the most interesting example I can choose for close examination will be that of a mountain in Chamouni, called the Aiguille Bouchard, now familiar to the eye of every traveller, being the ridge which rises, exactly opposite the Montanvert, beyond the Mer de Glace. The structure of this crest is best seen from near the foot of the Montanvert, on the road to the source of the Arveiron, whence the top of it, _a_, presents itself under the outline given rudely in the opposite plate (+33+), in which it will be seen that, while the main energy of the mountain ma.s.s tosses itself against the central chain of Mont Blanc (which is on the right hand), it is met by a group of counter-crests, like the recoil of a broken wave cast against it from the other side; and yet, as the recoiling water has a sympathy with the under swell of the very wave against which it clashes, the whole ma.s.s writhes together in strange unity of mountain pa.s.sion; so that it is almost impossible to persuade oneself, after long looking at it, that the crests have not indeed been once fused and tossed into the air by a tempest which had mastery over them, as the winds have over ocean.

-- 12. And yet, if we examine the crest structure closely, we shall find that nearly all these curvatures are obtained by Nature's skilful handling of perfectly straight beds,--only the meeting of those two waves of crest is indeed indicative of the meeting of two ma.s.ses of different rocks; it marks that junction of the slaty with the compact crystallines, which has before been noticed as the princ.i.p.al mystery of rock structure. To this junction my attention was chiefly directed during my stay at Chamouni, as I found it was always at that point that Nature produced the loveliest mountain forms. Perhaps the time I gave to the study of it may have exaggerated its interest in my eyes; and the reader who does not care for these geological questions, except in their direct bearing upon art, may, without much harm, miss the next seven paragraphs, and go on at the twenty-first. Yet there is one point, in a Turner drawing presently to be examined, which I cannot explain without inflicting the tediousness even of these seven upon him.

[Ill.u.s.tration: J. Ruskin. R. P. Cuff.

33. Leading Contours of Aiguille Bouchard.]

-- 13. First, then, the right of the Aiguille Bouchard to be called a crest at all depends, not on the slope from _a_ to _b_, Plate +33+, but on that from _a_ to _h_. The slope from _a_ to _b_ is a perspective deception; _b_ is much the highest point of the two. Seen from the village of Chamouni, the range presents itself under the outline Fig.

54, the same points in each figure being indicated by the same letters.

From the end of the valley the supremacy of the ma.s.s _b c_ is still more notable. It is altogether with mountains as with human spirits, you never know which is greatest till they are far away.

[Ill.u.s.tration: FIG. 54.]

-- 14. It will be observed also, that the beauty of the crest, in both Plate +33+ and Fig. 54, depends on the gradually increasing steepness of the lines of slope between _a_ and _b_. This is in great part deceptive, being obtained by the receding of the crest into a great mountain crater, or basin, as explained in -- 11. But this very recession is a matter of interest, for it takes place exactly on the line above spoken of, where the slaty crystallines of the crest join the compact crystallines of the aiguilles; at which junction a correspondent chasm or recession, of some kind or another, takes place along the whole front of Mont Blanc.

-- 15. In the third paragraph of the last chapter we had occasion to refer to the junction of the slaty and compact crystallines at the roots of the aiguilles. It will be seen in the figure there given, that this change is not sudden, but gradated. The rocks to be joined are of the two types represented in Fig. 3, p. 106 (for convenience' sake I shall in the rest of this chapter call the slaty rock gneiss, and the compact rock protogine, its usual French name). Fig. 55 shows the general manner of junction, beds of gneiss occurring in the middle of the protogine, and of protogine in the gneiss; sometimes one touching the other so closely, that a hammer-stroke breaks off a piece of both; sometimes one pa.s.sing into the other by a gradual change, like the zones of a rainbow; the only general phenomenon being this, that the higher up the hill the gneiss is, the harder it is (so that while it often yields to the pressure of the finger down in the valley, on the Montanvert it is nearly as hard as protogine); and, on the other hand, the lower down the hill, or the nearer the gneiss, the protogine is, the finer it is in grain. But still the actual transition from one to the other is usually within a few fathoms; and it is that transition, and the preparation for it, which causes the great step, or jag, on the flank of the chain, and forms the tops of the Aiguille Bouchard, Charmoz ridges, Tapia, Montagne de la Cote, Montagne de Taconay, and Aiguille du Goute.

[Ill.u.s.tration: FIG. 55.]

[Ill.u.s.tration: FIG. 56.]

[Ill.u.s.tration: FIG. 57.]

[Ill.u.s.tration: FIG. 58.]

-- 16. But what most puzzled me was the intense _straightness_ of the lines of the gneiss beds, dipping, as it seemed, under the Mont Blanc.

For it has been a chief theory with geologists that these central protogine rocks have once been in fusion, and have risen up in molten fury, overturning and altering all the rocks around. But every day, as I looked at the crested flanks of the Mont Blanc, I saw more plainly the exquisite _regularity_ of the slopes of the beds, ruled, it seemed, with an architect's rule, along the edge of their every flake from the summits to the valley. And this surprised me the more because I had always heard it stated that the beds of the lateral crests, _a_ and _b_, Fig. 56, varied in slope, getting less and less inclined as they descended, so as to arrange themselves somewhat in the form of a fan. It may be so; but I can only say that all my observations and drawings give an opposite report, and that the beds seemed invariably to present themselves to the eye and the pencil in parallelism, modified only by the phenomena just explained (---- 9, 10). Thus the entire ma.s.s of the Aiguille Bouchard, of which only the top is represented in Plate +33+, appeared to me in profile, as in Fig. 57, dependent for all its effect and character on the descent of the beds in the directions of the dotted lines, _a_, _b_, _d_. The interrupting s.p.a.ce, _g g_, is the Glacier des Bois; M is the Montanvert; _c_, _c_, the rocks under the glacier, much worn by the fall of avalanches, but, for all that, showing the steep lines still with the greatest distinctness. Again, looking down the valley instead of up, so as to put the Mont Blanc on the left hand, the princ.i.p.al crests which support it, Taconay and La Cote, always appeared to me constructed as in Plate +35+ (p. 212), they also depending for all their effect on the descent of the beds in diagonal lines towards the left. Nay, half-way up the Breven, whence the structure of the Mont Blanc is commanded, as far as these lower b.u.t.tresses are concerned, better than from the top of the Breven, I drew carefully the cleavages of the beds, as high as the edge of the Aiguille de Goute, and found them exquisitely parallel throughout; and again on the Cormayeur side, though less steep, the beds _a_, _b_, Fig. 58, traversing the vertical irregular fissures of the great aiguille of the Allee Blanche, as seen over the Lac de Combal, still appeared to me perfectly regular and parallel.[71] I have not had time to trace them round, through the Aiguille de Biona.s.say, and above the Col de Bonhomme, though I know the relations of the beds of limestone to the gneiss on the latter col are most notable and interesting. But, as far as was required for any artistical purposes, I perfectly ascertained the fact that, whatever their real structure might be, these beds did appear, through the softer contours of the hill, as straight and parallel; that they continued to appear so until near the tops of the crests; and that those tops seemed, in some mysterious way, dependent on the junction of the gneissitic beds with, or their transition into, the harder protogine of the aiguilles.

Look back to Plate +33+. The peak of the Bouchard, _a_, is of gneiss, and its beds run down in lines originally straight, but more or less hollowed by weathering, to the point _h_, where they plunge under debris. But the point _b_ is, I believe, of protogine; and all the opposed writhing of the waves of rock to the right appears to be in consequence of the junction.

[Ill.u.s.tration: 34. Cleavages of Aiguille Bouchard.]

-- 17. The way in which these curves are produced cannot, however, be guessed at until we examine the junction more closely. Ascending about five hundred feet above the cabin of the Montanvert, the opposite crest of the Bouchard, from _a_ to _c_, Plate +33+, is seen more in front, expanded into the jagged line, _a_ to _c_, Plate +34+, and the beds, with their fractures, are now seen clearly throughout the ma.s.s, namely:

1st. (See references on plate). The true gneiss beds dipping down in the direction G H, the point H being the same as _h_ in Plate +33+. These are the beds so notable for their accurate straightness and parallelism.

2nd. The smooth fractures which in the middle of the etching seem to divide the column of rock into a kind of brickwork. They are very neat and sharp, running nearly at right angles with the true beds.[72]

3rd. The curved fractures of the aiguilles (seen first under the letter _b_, and seeming to push outwards against the gneiss beds[73]) continuing through _c_ and the spur below.

4th. An irregular cleavage, something like that of starch, showing itself in broken vertical lines.

5th. Writhing lines, cut by water. These have the greatest possible influence on the aspect of the precipice: they are not merely caused by torrents, but by falls of winter snow, and stones from the glacier moraines, so that the cliff being continually worn away at the foot of it, is wrought into a great amphitheatre, of which the receding sweep continually varies the apparent steepness of the crest, as already explained. I believe in ancient times the great Glacier des Bois itself used to fill this amphitheatre, and break right up against the base of the Bouchard.

6th. Curvatures worn by water over the back of the crest towards the valley, in the direction _g i_.

7th. A tendency (which I do not understand) to form horizontal ma.s.ses at the levels _k_ and _l_.[74]

[Ill.u.s.tration: FIG. 61.]

-- 18. The reader may imagine what strange harmonies and changes of line must result throughout the ma.s.s of the mountain from the varied prevalence of one or other of these secret inclinations of its rocks (modified, also, as they are by perpetual deceptions of perspective), and how completely the rigidity or parallelism of any one of them is conquered by the fitful urgencies of the rest,--a sevenfold action seeming to run through every atom of crag. For the sake of clearness, I have shown in this plate merely leading lines; the next (Plate +35+, opposite) will give some idea of the complete aspect of two of the princ.i.p.al crests on the Mont Blanc flanks, known as the Montagne de la Cote, and Montagne de Taconay, _c_ and _t_ in Fig. 22, at page 163. In which note, first, that the eminences marked _a a_, _b b_, _c c_, here, in the reference figure (61), are in each of the mountains correspondent, and indicate certain changes in the conditions of their beds at those points. I have no doubt the two mountains were once one ma.s.s, and that they have been sawn asunder by the great glacier of Taconay, which descends between them; and similarly the Montagne de la Cote sawn from the Tapia by the glacier des Bossons, B B in reference figure.

[Ill.u.s.tration: 35. Crests of La Cote and Taconay.]

[Ill.u.s.tration: 36. Crest of La Cote.]

-- 19. Note, secondly, the general tendency in each mountain to throw itself into concave curves towards the Mont Blanc, and descend in rounded slopes to the valley; more or less interrupted by the direct manifestation of the straight beds, which are indeed, in this view of Taconay, the princ.i.p.al features of it. They necessarily become, however, more prominent in the outline etching than in the scene itself, because in reality the delicate cleavages are lost in distance or in mist, and the effects of light bring out the rounded forms of the larger ma.s.ses; and wherever the clouds fill the hollows between, as they are apt to do, (the glaciers causing a chillness in the ravines, while the wind, blowing _up_ the larger valleys, clears the edges of the crests,) the summits show themselves as in Plate 36, dividing, with their dark frontlets, the perpetual sweep of the glaciers and the clouds.[75]

-- 20. Of the aqueous curvatures of this crest, we shall have more to say presently; meantime let us especially observe how the providential laws of beauty, acting with reversed data, arrive at similar results in the aiguilles and crests. In the aiguilles, which are of such hard rock that the fall of snow and trickling of streams do not affect them, the inner structure is so disposed as to bring out the curvatures by the mere fracture. In the crests and lower hills, which are of softer rock, and largely influenced by external violence, the inner structure is straight, and the necessary curvatures are produced by perspective, by external modulation, and by the balancing of adverse influences of cleavage. But, as the accuracy of an artist's eye is usually shown by his perceiving the inner anatomy which regulates growth and form, and as in the aiguilles, while we watch them, we are continually discovering new curves, so in the crests, while we watch them, we are continually discovering new straightnesses; and nothing more distinguishes good mountain-drawing, or mountain-seeing, from careless and inefficient mountain-drawing, than the observance of the marvellous parallelisms which exist among the beds of the crests.

[Ill.u.s.tration: FIG. 62.]

-- 21. It indeed happens, not unfrequently, that in hills composed of somewhat soft rock, the aqueous contours will so prevail over the straight cleavage as to leave nothing manifest at the first glance but sweeping lines like those of waves. Fig. 43, p. 196, is the crest of a mountain on the north of the valley of Chamouni, known, from the rapid decay and fall of its crags, as the Aiguille _Pourri_; and at first there indeed seems little distinction between its contours and those of the summit of a sea wave. Yet I think also, if it _were_ a wave, we should immediately suppose the tide was running towards the right hand; and if we examined the reason for this supposition, we should perceive that along the ridge the steepest falls of crag were always on the right-hand side; indicating a tendency in them to break rather in the direction of the line _a b_ than any other. If we go half-way down the Montanvert, and examine the left side of the crest somewhat more closely, we shall find this tendency still more definitely visible, as in Fig. 62.

-- 22. But what, then, has given rise to all those coiled plungings of the crest hither and thither, yet with such strange unity of motion?

Yes. There is the cloud. How the top of the hill was first shaped so as to let the currents of water act upon it in so varied a way we know not, but I think that the appearance of _interior_ force of elevation is for the most part deceptive. The series of beds would be found, if examined in section, very uniform in their arrangement, only a little harder in one place, and more delicate in another. A stream receives a slight impulse this way or that, at the top of the hill, but increases in energy and sweep as it descends, gathering into itself others from its sides, and uniting their power with its own. A single knot of quartz occurring in a flake of slate at the crest of the ridge may alter the entire destinies of the mountain form. It may turn the little rivulet of water to the right or left, and that little turn will be to the future direction of the gathering stream what the touch of a finger on the barrel of a rifle would be to the direction of the bullet. Each succeeding year increases the importance of every determined form, and arranges in ma.s.ses yet more and more harmonious, the promontories shaped by the sweeping of the eternal waterfalls.

-- 23. The importance of the results thus obtained by the slightest change of direction in the infant streamlets, furnishes an interesting type of the formation of human characters by habit. Every one of those notable ravines and crags is the expression, not of any sudden violence done to the mountain, but of its little _habits_, persisted in continually. It was created with one ruling instinct; but its destiny depended nevertheless, for effective result, on the direction of the small and all but invisible tricklings of water, in which the first shower of rain found its way down its sides. The feeblest, most insensible oozings of the drops of dew among its dust were in reality arbiters of its eternal form; commissioned, with a touch more tender than that of a child's finger,--as silent and slight as the fall of a half-checked tear on a maiden's cheek,--to fix for ever the forms of peak and precipice, and hew those leagues of lifted granite into the shapes that were to divide the earth and its kingdoms. Once the little stone evaded,--once the dim furrow traced,--and the peak was for ever invested with its majesty, the ravine for ever doomed to its degradation. Thenceforward, day by day, the subtle habit gained in power; the evaded stone was left with wider bas.e.m.e.nt; the chosen furrow deepened with swifter-sliding wave; repentance and arrest were alike impossible, and hour after hour saw written in larger and rockier characters upon the sky, the history of the choice that had been directed by a drop of rain, and of the balance that had been turned by a grain of sand.

[Ill.u.s.tration: FIG. 63.]

-- 24. Such are the princ.i.p.al laws, relating to the crested mountains, for the expression of which we are to look to art; and we shall accordingly find good and intelligent mountain-drawing distinguished from bad mountain-drawing, by an indication, first, of the artist's recognition of some great harmony among the summits, and of their tendency to throw themselves into tidal waves, closely resembling those of the sea itself; sometimes in free tossing towards the sky, but more frequently still in the form of _breakers_, concave and steep on one side, convex and less steep on the other; secondly, by his indication of straight beds or fractures, continually stiffening themselves through the curves in some given direction.