The Storm-Cloud of the Nineteenth Century
No colors that can be fixed in earth can ever represent to you the luster of these cloudy ones. But the actual tints may be shown you in a lower key, and to a certain extent their power and relation to each other.
I have painted the diagram here shown you with colors prepared for me lately by Messrs. Newman, which I find brilliant to the height that pigments can be; and the ready kindness of Mr. Wilson Barrett enables me to show you their effect by a white light as pure as that of the day. The diagram is enlarged from my careful sketch of the sunset of 1st October, 1868, at Abbeville, which was a beautiful example of what, in fine weather about to pass into storm, a sunset could then be, in the districts of Kent and Picardy unaffected by smoke. In reality, the ruby and vermilion clouds were, by myriads, more numerous than I have had time to paint: but the general character of their grouping is well enough expressed. All the illumined clouds are high in the air, and nearly motionless; beneath them, electric storm-cloud rises in a threatening cumulus on the right, and drifts in dark flakes across the horizon, casting from its broken masses radiating shadows on the upper clouds. These shadows are traced, in the first place by making the misty blue of the open sky more transparent, and therefore darker; and secondly, by entirely intercepting the sunbeams on the bars of cloud, which, within the shadowed spaces, show dark on the blue instead of light.
But, mind, all that is done by reflected light—and in that light you never get a green ray from the reflecting cloud; there is no such thing in nature as a green lighted cloud relieved from a red sky,—the cloud is always red, and the sky green, and green, observe, by transmitted, not reflected light.
But now note, there is another kind of cloud, pure white, and exquisitely delicate; which acts not by reflecting, nor by refracting, but, as it is now called, diffracting, the sun's rays. The particles of this cloud are said—with what truth I know not15—to send the sunbeams round them instead of through them; somehow or other, at any rate, they resolve them into their prismatic elements; and then you have literally a kaleidoscope in the sky, with every color of the prism in absolute purity; but above all in force, now, the ruby red and the green,—with purple, and violet-blue, in a virtual equality, more definite than that of the rainbow. The red in the rainbow is mostly brick red, the violet, though beautiful, often lost at the edge; but in the prismatic cloud the violet, the green, and the ruby are all more lovely than in any precious stones, and they are varied as in a bird's breast, changing their places, depths, and extent at every instant.
The main cause of this change being, that the prismatic cloud itself is always in rapid, and generally in fluctuating motion. "A light veil of clouds had drawn itself," says Professor Tyndall, in describing his solitary ascent of Monte Rosa, "between me and the sun, and this was flooded with the most brilliant dyes. Orange, red, green, blue—all the hues produced by diffraction—were exhibited in the utmost splendor.
"Three times during my ascent (the short ascent of the last peak) similar veils drew themselves across the sun, and at each passage the splendid phenomena were renewed. There seemed a tendency to form circular zones of color round the sun; but the clouds were not sufficiently uniform to permit of this, and they were consequently broken into spaces, each steeped with the color due to the condition of the cloud at the place."
Three times, you observe, the veil passed, and three times another came, or the first faded and another formed; and so it is always, as far as I have registered prismatic cloud: and the most beautiful colors I ever saw were on those that flew fastest.
This second diagram is enlarged admirably by Mr. Arthur Severn from my sketch of the sky in the afternoon of the 6th of August, 1880, at Brantwood, two hours before sunset. You are looking west by north, straight towards the sun, and nearly straight towards the wind. From the west the wind blows fiercely towards you out of the blue sky. Under the blue space is a flattened dome of earth-cloud clinging to, and altogether masking the form of, the mountain, known as the Old Man of Coniston.
The top of that dome of cloud is two thousand eight hundred feet above the sea, the mountain two thousand six hundred, the cloud lying two hundred feet deep on it. Behind it, westward and seaward, all's clear; but when the wind out of that blue clearness comes over the ridge of the earth-cloud, at that moment and that line, its own moisture congeals into these white—I believe, ice-clouds; threads, and meshes, and tresses, and tapestries, flying, failing, melting, reappearing; spinning and unspinning themselves, coiling and uncoiling, winding and unwinding, faster than eye or thought can follow: and through all their dazzling maze of frosty filaments shines a painted window in palpitation; its pulses of color interwoven in motion, intermittent in fire,—emerald and ruby and pale purple and violet melting into a blue that is not of the sky, but of the sunbeam;—purer than the crystal, softer than the rainbow, and brighter than the snow.
But you must please here observe that while my first diagram did with some adequateness represent to you the color facts there spoken of, the present diagram can only explain, not reproduce them. The bright reflected colors of clouds can be represented in painting, because they are relieved against darker colors, or, in many cases, are dark colors, the vermilion and ruby clouds being often much darker than the green or blue sky beyond them. But in the case of the phenomena now under your attention, the colors are all brighter than pure white,—the entire body of the cloud in which they show themselves being white by transmitted light, so that I can only show you what the colors are, and where they are,—but leaving them dark on the white ground. Only artificial, and very high illumination would give the real effect of them,—painting cannot.
Enough, however, is here done to fix in your minds the distinction between those two species of cloud,—one, either stationary,16 or slow in motion, reflecting unresolved light; the other, fast-flying, and transmitting resolved light. What difference is there in the nature of the atoms, between those two kinds of clouds? I leave the question with you for to-day, merely hinting to you my suspicion that the prismatic cloud is of finely-comminuted water, or ice,17 instead of aqueous vapor; but the only clue I have to this idea is in the purity of the rainbow formed in frost mist, lying close to water surfaces. Such mist, however, only becomes prismatic as common rain does, when the sun is behind the spectator, while prismatic clouds are, on the contrary, always between the spectator and the sun.
The main reason, however, why I can tell you nothing yet about these colors of diffraction or interference, is that, whenever I try to find anything firm for you to depend on, I am stopped by the quite frightful inaccuracy of the scientific people's terms, which is the consequence of their always trying to write mixed Latin and English, so losing the grace of the one and the sense of the other. And, in this point of the diffraction of light I am stopped dead by their confusion of idea also, in using the words undulation and vibration as synonyms. "When," says Professor Tyndall, "you are told that the atoms of the sun vibrate at different rates, and produce waves of different sizes,—your experience of water-waves will enable you to form a tolerably clear notion of what is meant."
'Tolerably clear'!—your toleration must be considerable, then. Do you suppose a water-wave is like a harp-string? Vibration is the movement of a body in a state of tension,—undulation, that of a body absolutely lax. In vibration, not an atom of the body changes its place in relation to another,—in undulation, not an atom of the body remains in the same place with regard to another. In vibration, every particle of the body ignores gravitation, or defies it,—in undulation, every particle of the body is slavishly submitted to it. In undulation, not one wave is like another; in vibration, every pulse is alike. And of undulation itself, there are all manner of visible conditions, which are not true conditions. A flag ripples in the wind, but it does not undulate as the sea does,—for in the sea, the water is taken from the trough to put on to the ridge, but in the flag, though the motion is progressive, the bits of bunting keep their place. You see a field of corn undulating as if it was water,—it is different from the flag, for the ears of corn bow out of their places and return to them,—and yet, it is no more like the undulation of the sea, than the shaking of an aspen leaf in a storm, or the lowering of the lances in a battle.
And the best of the jest is, that after mixing up these two notions in their heads inextricably, the scientific people apply both when neither will fit; and when all undulation known to us presumes weight, and all vibration, impact,—the undulating theory of light is proposed to you concerning a medium which you can neither weigh nor touch!
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1
The vapor over the pool of Anger in the 'Inferno,' the clogging stench which rises from Caina, and the fog of the circle of Anger in the 'Purgatorio' resemble, indeed, the cloud of the Plague-wind very closely,—but are conceived only as supernatural. The reader will no doubt observe, throughout the following lecture, my own habit of speaking of beautiful things as 'natural,' and of ugly ones as 'unnatural.' In the conception of recent philosophy, the world is one Kosmos in which diphtheria is held to be as natural as song, and cholera as digestion. To my own mind, and the more distinctly the more I see, know, and feel, the Earth, as prepared for the abode of man, appears distinctly ruled by agencies of health and disease, of which the first may be aided by his industry, prudence, and piety; while the destroying laws are allowed to prevail against him, in the degree in which he allows himself in idleness, folly, and vice. Had the point been distinctly indicated where the degrees of adversity necessary for his discipline pass into those intended for his punishment, the world would have been put under a manifest theocracy; but the declaration of the principle is at least distinct enough to have convinced all sensitive and earnest persons, from the beginning of speculation in the eyes and mind of Man: and it has been put in my power by one of the singular chances which have always helped me in my work when it was in the right direction, to present to the University of Oxford the most distinct expression of this first principle of mediæval Theology which, so far as I know, exists in fifteenth-century art. It is one of the drawings of the Florentine book which I bought for a thousand pounds, against the British Museum, some ten or twelve years since; being a compendium of classic and mediæval religious symbolism. In the two pages of it, forming one picture, given to Oxford, the delivery of the Law on Sinai is represented on the left hand, (contrary to the Scriptural narrative, but in deeper expression of the benediction of the Sacred Law to all nations,) as in the midst of bright and calm light, the figure of the Deity being supported by luminous and level clouds, and attended by happy angels: while opposite, on the right hand, the worship of the Golden Calf is symbolized by a single decorated pillar, with the calf on its summit, surrounded by the clouds and darkness of a furious storm, issuing from the mouths of fiends;—uprooting the trees, and throwing down the rocks, above the broken tables of the Law, of which the fragments lie in the foreground.
2
These conditions are mainly in the arrangement of the lower rain-clouds in flakes thin and detached enough to be illuminated by early or late sunbeams: their textures are then more softly blended than those of the upper cirri, and have the qualities of painted, instead of burnished or inflamed, color.
They were thus described in the 4th chapter of the 7th part of 'Modern Painters':—
"Often in our English mornings, the rain-clouds in the dawn form soft level fields, which melt imperceptibly into the blue; or when of less extent, gather into apparent bars, crossing the sheets of broader cloud above; and all these bathed throughout in an unspeakable light of pure rose-color, and purple, and amber, and blue, not shining, but misty-soft, the barred masses, when seen nearer, found to be woven in tresses of cloud, like floss silk, looking as if each knot were a little swathe or sheaf of lighted rain.
"No clouds form such skies, none are so tender, various, inimitable; Turner himself never caught them. Correggio, putting out his whole strength, could have painted them,—no other man."
3
I did not, in writing this sentence, forget Mr. Gladstone's finely scholastic enthusiasm for Homer; nor Mr. Newton's for Athenian—(I wish it had not been also for Halicarnassian) sculpture. But Byron loved Greece herself—through her death—and to his own; while the subsequent refusal of England to give Greece one of our own princes for a king, has always been held by me the most ignoble, cowardly, and lamentable, of all our base commercial impolicies.
4
'Deepening' clouds.—Byron never uses an epithet vainly,—he is the most accurate, and therefore the most powerful, of all modern describers. The deepening of the cloud is essentially necessary to the redness of the orb. Ordinary observers are continually unaware of this fact, and imagine that a red sun can be darker than the sky round it! Thus Mr. Gould, though a professed naturalist, and passing most of his life in the open air, over and over again, in his 'British Birds,' draws the setting sun dark on the sky!
5
'Like the blood he predicts.'—The astrological power of the planet Mars was of course ascribed to it in the same connection with its red color. The reader may be interested to see the notice, in 'Modern Painters,' of Turner's constant use of the same symbol; partly an expression of his own personal feeling, partly, the employment of a symbolic language known to all careful readers of solar and stellar tradition.
"He was very definitely in the habit of indicating the association of any subject with circumstances of death, especially the death of multitudes, by placing it under one of his most deeply crimsoned sunset skies.
"The color of blood is thus plainly taken for the leading tone in the storm-clouds above the 'Slave-ship.' It occurs with similar distinctness in the much earlier picture of 'Ulysses and Polypheme,' in that of 'Napoleon at St. Helena,' and, subdued by softer hues, in the 'Old Téméraire.'
"The sky of this Goldau is, in its scarlet and crimson, the deepest in tone of all that I know in Turner's drawings.
"Another feeling, traceable in several of his former works, is an acute sense of the contrast between the careless interests and idle pleasures of daily life, and the state of those whose time for labor, or knowledge, or delight, is passed forever. There is evidence of this feeling in the introduction of the boys at play in the churchyard of Kirkby Lonsdale, and the boy climbing for his kite among the thickets above the little mountain churchyard of Brignal-bank; it is in the same tone of thought that he has placed here the two figures fishing, leaning against these shattered flanks of rock,—the sepulchral stones of the great mountain Field of Death."
6
'Thy lore unto calamity.'—It is, I believe, recognized by all who have in any degree become interested in the traditions of Chaldean astrology, that its warnings were distinct,—its promises deceitful. Horace thus warns Leuconoe against reading the Babylonian numbers to learn the time of her death,—he does not imply their promise of previous happiness; and the continually deceptive character of the Delphic oracle itself, tempted always rather to fatal than to fortunate conduct, unless the inquirer were more than wise in his reading. Byron gathers into the bitter question all the sorrow of former superstition, while in the lines italicized, just above, he sums in the briefest and plainest English, all that we yet know, or may wisely think, about the Sun. It is the 'Burning oracle' (other oracles there are by sound, or feeling, but this by fire) of all that lives; the only means of our accurate knowledge of the things round us, and that affect our lives: it is the fountain of all life,—Byron does not say the origin;—the origin of life would be the origin of the sun itself; but it is the visible source of vital energy, as the spring is of a stream, though the origin is the sea. "And symbol of Him who bestows it."—This the sun has always been, to every one who believes there is a bestower; and a symbol so perfect and beautiful that it may also be thought of as partly an apocalypse.
7
'More beautiful in that variety.'—This line, with the one italicized beneath, expresses in Myrrha's mind, the feeling which I said, in the outset, every thoughtful watcher of heaven necessarily had in those old days; whereas now, the variety is for the most part, only in modes of disagreeableness; and the vapor, instead of adding light to the unclouded sky, takes away the aspect and destroys the functions of sky altogether.
8
'Steam out of an engine funnel.'—Compare the sixth paragraph of Professor Tyndall's 'Forms of Water,' and the following seventh one, in which the phenomenon of transparent steam becoming opaque is thus explained. "Every bit of steam shrinks, when chilled, to a much more minute particle of water. The liquid particles thus produced form a kind of water dust of exceeding fineness, which floats in the air, and is called a cloud."
But the author does not tell us, in the first place, what is the shape or nature of a 'bit of steam,' nor, in the second place, how the contraction of the individual bits of steam is effected without any diminution of the whole mass of them, but on the contrary, during its steady expansion; in the third place he assumes that the particles of water dust are solid, not vesicular, which is not yet ascertained; in the fourth place, he does not tell us how their number and size are related to the quantity of invisible moisture in the air; in the fifth place, he does not tell us how cool invisible moisture differs from hot invisible moisture; and in the sixth, he does not tell us why the cool visible moisture stays while the hot visible moisture melts away. So much for the present state of 'scientific' information, or at least communicativeness, on the first and simplest conditions of the problem before us!
In its wider range that problem embraces the total mystery of volatile power in substance; and of the visible states consequent on sudden—and presumably, therefore, imperfect—vaporization; as the smoke of frankincense, or the sacred fume of modern devotion which now fills the inhabited world, as that of the rose and violet its deserts. What,—it would be useful to know, is the actual bulk of an atom of orange perfume?—what of one of vaporized tobacco, or gunpowder?—and where do these artificial vapors fall back in beneficent rain? or through what areas of atmosphere exist, as invisible, though perhaps not innocuous, cloud?
All these questions were put, closely and precisely, four-and-twenty years ago, in the 1st chapter of the 7th part of 'Modern Painters,' paragraphs 4 to 9, of which I can here allow space only for the last, which expresses the final difficulties of the matter better than anything said in this lecture:—
"But farther: these questions of volatility, and visibility, and hue, are all complicated with those of shape. How is a cloud outlined? Granted whatever you choose to ask, concerning its material, or its aspect, its loftiness and luminousness,—how of its limitation? What hews it into a heap, or spins it into a web? Cold is usually shapeless, I suppose, extending over large spaces equally, or with gradual diminution. You cannot have in the open air, angles, and wedges, and coils, and cliffs, of cold. Yet the vapor stops suddenly, sharp and steep as a rock, or thrusts itself across the gates of heaven in likeness of a brazen bar; or braids itself in and out, and across and across, like a tissue of tapestry; or falls into ripples, like sand; or into waving shreds and tongues, as fire. On what anvils and wheels is the vapor pointed, twisted, hammered, whirled, as the potter's clay? By what hands is the incense of the sea built up into domes of marble?"
9
The opposed conditions of the higher and lower orders of cloud, with the balanced intermediate one, are beautifully seen on mountain summits of rock or earth. On snowy ones they are far more complex: but on rock summits there are three distinct forms of attached cloud in serene weather; the first that of cloud veil laid over them, and falling in folds through their ravines, (the obliquely descending clouds of the entering chorus in Aristophanes); secondly, the ascending cloud, which develops itself loosely and independently as it rises, and does not attach itself to the hill-side, while the falling veil cloud clings to it close all the way down;—and lastly the throned cloud, which rests indeed on the mountain summit, with its base, but rises high above into the sky, continually changing its outlines, but holding its seat perhaps all day long.
These three forms of cloud belong exclusively to calm weather; attached drift cloud, (see Note 11) can only be formed in the wind.
10
'Glaciers of the Alps,' page 10.—"Let a pound weight be placed upon a cube of granite" (size of supposed cube not mentioned), "the cube is flattened, though in an infinitesimal degree. Let the weight be removed, the cube remains a little flattened. Let us call the cube thus flattened No. 1. Starting with No. 1 as a new mass, let the pound weight be laid upon it. We have a more flattened mass, No. 2.... Apply this to squeezed rocks, to those, for example, which form the base of an obelisk like the Matterhorn,—the conclusion seems inevitable that the mountain is sinking by its own weight," etc., etc. Similarly the Nelson statue must be gradually flattening the Nelson column, and in time Cleopatra's needle will be as flat as her pincushion?
11
'Glaciers of the Alps,' page 146.—"The sun was near the western horizon, and I remained alone upon the Grat to see his last beams illuminate the mountains, which, with one exception, were without a trace of cloud.
"This exception was the Matterhorn, the appearance of which was extremely instructive. The obelisk appeared to be divided in two halves by a vertical line, drawn from its summit half-way down, to the windward of which we had the bare cliffs of the mountain; and to the left of it a cloud which appeared to cling tenaciously to the rocks.
"In reality, however, there was no clinging; the condensed vapor incessantly got away, but it was ever renewed, and thus a river of cloud had been sent from the mountain over the valley of Aosta. The wind, in fact, blew lightly up the valley of St. Nicholas, charged with moisture, and when the air that held it rubbed against the cold cone of the Matterhorn, the vapor was chilled and precipitated in his lee."
It is not explained, why the wind was not chilled by rubbing against any of the neighboring mountains, nor why the cone of the Matterhorn, mostly of rock, should be colder than cones of snow. The phenomenon was first described by De Saussure, who gives the same explanation as Tyndall; and from whom, in the first volume of 'Modern Painters,' I adopted it without sufficient examination. Afterwards I re-examined it, and showed its fallacy, with respect to the cap or helmet cloud, in the fifth volume of 'Modern Painters,' page 124, in the terms given in the subjoined note,