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!

All communicable vibration—of course I mean—and in dead matter: You may fall a shivering on your own account, if you like, but you can't get a billiard-ball to fall a shivering on its own account.18

Yet observe that in thus signalizing the inaccuracy of the terms in which they are taught, I neither accept, nor assail, the conclusions respecting the oscillatory states of light, heat, and sound, which have resulted from the postulate of an elastic, though impalpable and imponderable ether, possessing the elasticity of air. This only I desire you to mark with attention,—that both light and sound are sensations of the animal frame, which remain, and must remain, wholly inexplicable, whatever manner of force, pulse, or palpitation may be instrumental in producing them: nor does any such force become light or sound, except in its rencontre with an animal. The leaf hears no murmur in the wind to which it wavers on the branches, nor can the clay discern the vibration by which it is thrilled into a ruby. The Eye and the Ear are the creators alike of the ray and the tone; and the conclusion follows logically from the right conception of their living power,—"He that planted the Ear, shall He not hear? He that formed the Eye, shall not He see?"

For security, therefore, and simplicity of definition of light, you will find no possibility of advancing beyond Plato's "the power that through the eye manifests color," but on that definition, you will find, alike by Plato and all great subsequent thinkers, a moral Science of Light founded, far and away more important to you than all the physical laws ever learned by vitreous revelation. Concerning which I will refer you to the sixth lecture which I gave at Oxford in 1872, on the relation of Art to the Science of Light ('The Eagle's Nest'), reading now only the sentence introducing its subject:—"The 'Fiat lux' of creation is therefore, in the deep sense, 'fiat anima,' and is as much, when you understand it, the ordering of Intelligence as the ordering of Vision. It is the appointment of change of what had been else only a mechanical effluence from things unseen to things unseeing,—from Stars, that did not shine, to Earth, that did not perceive,—the change, I say, of that blind vibration into the glory of the Sun and Moon for human eyes: so making possible the communication out of the unfathomable truth of that portion of truth which is good for us, and animating to us, and is set to rule over the day and over the night of our joy and our sorrow."

Returning now to our subject at the point from which I permitted myself, I trust not without your pardon, to diverge; you may incidentally, but carefully, observe, that the effect of such a sky as that represented in the second diagram, so far as it can be abstracted or conveyed by painting at all, implies the total absence of any pervading warmth of tint, such as artists usually call 'tone.' Every tint must be the purest possible, and above all the white. Partly, lest you should think, from my treatment of these two phases of effect, that I am insensible to the quality of tone,—and partly to complete the representation of states of weather undefiled by plague-cloud, yet capable of the most solemn dignity in saddening color, I show you, Diagram 3, the record of an autumn twilight of the year 1845,—sketched while I was changing horses between Verona and Brescia. The distant sky in this drawing is in the glowing calm which is always taken by the great Italian painters for the background of their sacred pictures; a broad field of cloud is advancing upon it overhead, and meeting others enlarging in the distance; these are rain-clouds, which will certainly close over the clear sky, and bring on rain before midnight: but there is no power in them to pollute the sky beyond and above them: they do not darken the air, nor defile it, nor in any way mingle with it; their edges are burnished by the sun like the edges of golden shields, and their advancing march is as deliberate and majestic as the fading of the twilight itself into a darkness full of stars.

These three instances are all I have time to give of the former conditions of serene weather, and of non-electric rain-cloud. But I must yet, to complete the sequence of my subject, show you one example of a good, old-fashioned, healthy, and mighty, storm.

In Diagram 4, Mr. Severn has beautifully enlarged my sketch of a July thundercloud of the year 1858, on the Alps of the Val d'Aosta, seen from Turin, that is to say, some twenty-five or thirty miles distant. You see that no mistake is possible here about what is good weather and what bad, or which is cloud and which is sky; but I show you this sketch especially to give you the scale of heights for such clouds in the atmosphere. These thunder cumuli entirely hide the higher Alps. It does not, however, follow that they have buried them, for most of their own aspect of height is owing to the approach of their nearer masses; but at all events, you have cumulus there rising from its base, at about three thousand feet above the plain, to a good ten thousand in the air.

White cirri, in reality parallel, but by perspective radiating, catch the sunshine above, at a height of from fifteen to twenty thousand feet; but the storm on the mountains gathers itself into a full mile's depth of massy cloud, every fold of it involved with thunder, but every form of it, every action, every color, magnificent:—doing its mighty work in its own hour and its own dominion, nor snatching from you for an instant, nor defiling with a stain, the abiding blue of the transcendent sky, or the fretted silver of its passionless clouds.

We so rarely now see cumulus cloud of this grand kind, that I will yet delay you by reading the description of its nearer aspect, in the 'Eagle's Nest.'

"The rain which flooded our fields the Sunday before last, was followed, as you will remember, by bright days, of which Tuesday the 20th (February, 1872) was, in London, notable for the splendor, towards the afternoon, of its white cumulus clouds. There has been so much black east wind lately, and so much fog and artificial gloom, besides, that I find it is actually some two years since I last saw a noble cumulus cloud under full light. I chanced to be standing under the Victoria Tower at Westminster, when the largest mass of them floated past, that day, from the northwest; and I was more impressed than ever yet by the awfulness of the cloud-form, and its unaccountableness, in the present state of our knowledge. The Victoria Tower, seen against it, had no magnitude: it was like looking at Mont Blanc over a lamp-post. The domes of cloud-snow were heaped as definitely: their broken flanks were as gray and firm as rocks, and the whole mountain, of a compass and height in heaven which only became more and more inconceivable as the eye strove to ascend it, was passing behind the tower with a steady march, whose swiftness must in reality have been that of a tempest: yet, along all the ravines of vapor, precipice kept pace with precipice, and not one thrust another.

"What is it that hews them out? Why is the blue sky pure there,—the cloud solid here; and edged like marble: and why does the state of the blue sky pass into the state of cloud, in that calm advance?

"It is true that you can more or less imitate the forms of cloud with explosive vapor or steam; but the steam melts instantly, and the explosive vapor dissipates itself. The cloud, of perfect form, proceeds unchanged. It is not an explosion, but an enduring and advancing presence. The more you think of it, the less explicable it will become to you."

Thus far then of clouds that were once familiar; now at last, entering on my immediate subject, I shall best introduce it to you by reading an entry in my diary which gives progressive description of the most gentle aspect of the modern plague-cloud.

"Bolton Abbey, 4th July, 1875.

Half-past eight, morning; the first bright morning for the last fortnight.

At half-past five it was entirely clear, and entirely calm; the moorlands glowing, and the Wharfe glittering in sacred light, and even the thin-stemmed field-flowers quiet as stars, in the peace in which—

'All trees and simples, great and small,That balmy leaf do bear,Than they were painted on a wall,No more do move, nor steir.'

But, an hour ago, the leaves at my window first shook slightly. They are now trembling continuously, as those of all the trees, under a gradually rising wind, of which the tremulous action scarcely permits the direction to be defined,—but which falls and returns in fits of varying force, like those which precede a thunderstorm—never wholly ceasing: the direction of its upper current is shown by a few ragged white clouds, moving fast from the north, which rose, at the time of the first leaf-shaking, behind the edge of the moors in the east.

This wind is the plague-wind of the eighth decade of years in the nineteenth century; a period which will assuredly be recognized in future meteorological history as one of phenomena hitherto unrecorded in the courses of nature, and characterized pre-eminently by the almost ceaseless action of this calamitous wind. While I have been writing these sentences, the white clouds above specified have increased to twice the size they had when I began to write; and in about two hours from this time—say by eleven o'clock, if the wind continue,—the whole sky will be dark with them, as it was yesterday, and has been through prolonged periods during the last five years. I first noticed the definite character of this wind, and of the clouds it brings with it, in the year 1871, describing it then in the July number of 'Fors Clavigera'; but little, at that time, apprehending either its universality, or any probability of its annual continuance. I am able now to state positively that its range of power extends from the North of England to Sicily; and that it blows more or less during the whole of the year, except the early autumn. This autumnal abdication is, I hope, beginning: it blew but feebly yesterday, though without intermission, from the north, making every shady place cold, while the sun was burning; its effect on the sky being only to dim the blue of it between masses of ragged cumulus. To-day it has entirely fallen; and there seems hope of bright weather, the first for me since the end of May, when I had two fine days at Aylesbury; the third, May 28th, being black again from morning to evening. There seems to be some reference to the blackness caused by the prevalence of this wind in the old French name of Bise, 'gray wind'; and, indeed, one of the darkest and bitterest days of it I ever saw was at Vevay in 1872."

The first time I recognized the clouds brought by the plague-wind as distinct in character was in walking back from Oxford, after a hard day's work, to Abingdon, in the early spring of 1871: it would take too long to give you any account this evening of the particulars which drew my attention to them; but during the following months I had too frequent opportunities of verifying my first thoughts of them, and on the first of July in that year wrote the description of them which begins the 'Fors Clavigera' of August, thus:—

"It is the first of July, and I sit down to write by the dismalest light that ever yet I wrote by; namely, the light of this midsummer morning, in mid-England, (Matlock, Derbyshire), in the year 1871.

"For the sky is covered with gray cloud;—not rain-cloud, but a dry black veil, which no ray of sunshine can pierce; partly diffused in mist, feeble mist, enough to make distant objects unintelligible, yet without any substance, or wreathing, or color of its own. And everywhere the leaves of the trees are shaking fitfully, as they do before a thunder-storm; only not violently, but enough to show the passing to and fro of a strange, bitter, blighting wind. Dismal enough, had it been the first morning of its kind that summer had sent. But during all this spring, in London, and at Oxford, through meager March, through changelessly sullen April, through despondent May, and darkened June, morning after morning has come gray-shrouded thus.

"And it is a new thing to me, and a very dreadful one. I am fifty years old, and more; and since I was five, have gleaned the best hours of my life in the sun of spring and summer mornings; and I never saw such as these, till now.

"And the scientific men are busy as ants, examining the sun, and the moon, and the seven stars, and can tell me all about them, I believe, by this time; and how they move, and what they are made of.

"And I do not care, for my part, two copper spangles how they move, nor what they are made of. I can't move them any other way than they go, nor make them of anything else, better than they are made. But I would care much and give much, if I could be told where this bitter wind comes from, and what it is made of.

"For, perhaps, with forethought, and fine laboratory science, one might make it of something else.

"It looks partly as if it were made of poisonous smoke; very possibly it may be: there are at least two hundred furnace chimneys in a square of two miles on every side of me. But mere smoke would not blow to and fro in that wild way. It looks more to me as if it were made of dead men's souls—such of them as are not gone yet where they have to go, and may be flitting hither and thither, doubting, themselves, of the fittest place for them.

"You know, if there are such things as souls, and if ever any of them haunt places where they have been hurt, there must be many about us, just now, displeased enough!"

The last sentence refers of course to the battles of the Franco-German campaign, which was especially horrible to me, in its digging, as the Germans should have known, a moat flooded with waters of death between the two nations for a century to come.

Since that Midsummer day, my attention, however otherwise occupied, has never relaxed in its record of the phenomena characteristic of the plague-wind; and I now define for you, as briefly as possible, the essential signs of it.

1. It is a wind of darkness,—all the former conditions of tormenting winds, whether from the north or east were more or less capable of co-existing with sunlight, and often with steady and bright sunlight; but whenever, and wherever the plague-wind blows, be it but for ten minutes, the sky is darkened instantly.

2. It is a malignant quality of wind, unconnected with any one quarter of the compass; it blows indifferently from all, attaching its own bitterness and malice to the worst characters of the proper winds of each quarter. It will blow either with drenching rain, or dry rage, from the south,—with ruinous blasts from the west,—with bitterest chills from the north,—and with venomous blight from the east.

Its own favorite quarter, however, is the southwest, so that it is distinguished in its malignity equally from the Bise of Provence, which is a north wind always, and from our own old friend, the east.

3. It always blows tremulously, making the leaves of the trees shudder as if they were all aspens, but with a peculiar fitfulness which gives them—and I watch them this moment as I write—an expression of anger as well as of fear and distress. You may see the kind of quivering, and hear the ominous whimpering, in the gusts that precede a great thunderstorm; but plague-wind is more panic-struck, and feverish; and its sound is a hiss instead of a wail.