Chapter II: The Cloud-Flocks

§ 1. From the tenor of the foregoing chapter, the reader will, I hope, be prepared to find me, though dogmatic (it is said) upon some occasions, anything rather than dogmatic respecting clouds. I will assume nothing concerning them, beyond the simple fact, that as a floating sediment forms in a saturated liquid, vapor forms in the body of the air; and all that I want the reader to be clear about in the outset is that this vapor floats in and with the wind (as, if you throw any thick coloring matter into a river, it floats with the stream), and that it is not blown before a denser volume of the wind, as a fleece of wool would be.

§ 2. At whatever height they form, clouds may be broadly considered as of two species only, massive and striated. I cannot find a better word than massive, though it is not a good one, for I mean it only to signify a fleecy arrangement in which no _lines_ are visible. The fleece may be so bright as to look like flying thistle-down, or so diffused as to show no visible outline at all. Still if it is all of one common texture, like a handful of wool, or a wreath of smoke, I call it massive.

On the other hand, if divided by parallel lines, so as to look more or less like spun-glass, I call it striated. In Plate 69, Fig. 4, the top of the Aiguille Dru (Chamouni) is seen emergent above low striated clouds, with heaped massive cloud beyond. I do not know in the least what causes this striation, except that it depends on the nature of the cloud, not on the wind. The strongest wind will not throw a cloud, massive by nature, into the linear form. It will toss it about, and tear it to pieces, but not spin it into threads. On the other hand, often without any wind at all, the cloud will spin itself into threads fine as gossamer. These threads are often said to be a prognostic of storm; but they are not produced by storm.

63. The Cloud-Flocks.]

§ 3. In the first volume, we considered all clouds as belonging to three regions, that of the cirrous, the central cloud, and the rain-cloud. It is of course an arrangement more of convenience than of true description, for cirrous clouds sometimes form low as well as high; and rain sometimes falls high as well as low. I will, nevertheless, retain this old arrangement, which is practically as serviceable as any.

Allowing, also, for various exceptions and modifications, these three bodies of cloud may be generally distinguished in our minds thus. The clouds of upper region are for the most part quiet, or seem to be so, owing to their distance. They are formed now of striated, now of massive substance; but always finely divided into large ragged flakes or ponderous heaps. These heaps (cumuli) and flakes, or drifts, present different phenomena, but must be joined in our minds under the head of central cloud. The lower clouds, bearing rain abundantly, are composed partly of striated, partly of massive substance; but may generally be comprehended under the term rain-cloud.

Our business in this chapter, then, is with the upper clouds, which, owing to their quietness and multitude, we may perhaps conveniently think of as the "cloud-flocks." And we have to discover if any laws of beauty attach to them, such as we have seen in mountains or tree-branches.

§ 4. On one of the few mornings of this winter, when the sky was clear, and one of the far fewer, on which its clearness was visible from the neighborhood of London,--which now entirely loses at least two out of three sunrises, owing to the environing smoke,--the dawn broke beneath a broad field of level purple cloud, under which floated ranks of divided cirri, composed of finely striated vapor.

It was not a sky containing any extraordinary number of these minor clouds; but each was more than usually distinct in separation from its neighbor, and as they showed in nearly pure pale scarlet on the dark purple ground, they were easily to be counted.

§ 5. There were five or six ranks, from the zenith to the horizon; that is to say, three distinct ones, and then two or three more running together, and losing themselves in distance, in the manner roughly shown in Fig. 79. The nearest rank was composed of more than 150 rows of cloud, set obliquely, as in the figure. I counted 150 which was near the mark, and then stopped, lest the light should fail, to count the separate clouds in some of the rows. The average number was 60 in each row, rather more than less.

There were therefore 150×60, that is, 9,000, separate clouds in this one rank, or about 50,000 in the field of sight. Flocks of Admetus under Apollo's keeping. Who else could shepherd such? He by day, dog Sirius by night; or huntress Diana herself--her bright arrows driving away the clouds of prey that would ravage her fair flocks. We must leave fancies, however; these wonderful clouds need close looking at. I will try to draw one or two of them before they fade.

§ 6. On doing which we find, after all, they are not much more like sheep than Canis Major is like a dog. They resemble more some of our old friends, the pine branches, covered with snow. The three forming the uppermost figure, in the Plate opposite, are as like three of the fifty thousand as I could get them, complex enough in structure, even this single group. Busy workers they must be, that twine the braiding of them all to the horizon, and down beyond it.

And who are these workers? You have two questions here, both difficult. What separates these thousands of clouds each from the other, and each about equally from the other? How can they be drawn asunder, yet not allowed to part? Looped lace as it were, richest point--invisible threads fastening embroidered cloud to cloud--the "plighted clouds" of Milton,--creatures of the element--

"That in the colors of the rainbow live
And play in the plighted clouds."

Compare Geraldine dressing:--

"Puts on her silken vestments white,
And tricks her hair in lovely plight."

And Britomart's--

"Her well-plighted frock
She low let fall, that flowed from her lanck side
Down to her foot, with careless modesty."

And, secondly, what bends each of them into these flame-like curves, tender and various, as motions of a bird, hither and thither? Perhaps you may hardly see the curves well in the softly finished forms; here they are plainer in rude outline, Fig. 80.[1]

§ 7. What is it that throws them into these lines?

Eddies of wind?

Nay, an eddy of wind will not stay quiet for three minutes, as that cloud did to be drawn; as all the others did, each in his place. You see there is perfect harmony among the curves. They all flow into each other as the currents of a stream do. If you throw dust that will float on the surface of a slow river, it will arrange itself in lines somewhat like these. To a certain extent, indeed, it is true that there are gentle currents of change in the atmosphere, which move slowly enough to permit in the clouds that follow them some appearance of stability. But how to obtain change so complex in an infinite number of consecutive spaces;--fifty thousand separate groups of current in half of a morning sky, with quiet invisible vapor between, or none--and yet all obedient to one ruling law, gone forth through their companies;--each marshalled to their white standards, in great unity of warlike march, unarrested, unconfused? "One shall not thrust another, they shall walk every one in his own path."

§ 8. These questions occur, at first sight, respecting every group of cirrus cloud. Whatever the form may be, whether branched, as in this instance, or merely rippled, or thrown into shield-like segments, as in Fig. 81--a frequent arrangement--there is still the same difficulty in accounting satisfactorily for the individual forces which regulate the similar shape of each mass, while all are moved by a general force that has apparently no influence on the divided structure. Thus the mass of clouds disposed as in Fig. 81, will probably move, mutually, in the direction of the arrow; that is to say, sideways, as far as their separate curvature is concerned. I suppose it probable that as the science of electricity is more perfectly systematized, the explanation of many circumstances of cloud-form will be rendered by it. At present I see no use in troubling the reader or myself with conjectures which a year's progress in science might either effectively contradict or supersede. All that I want is, that we should have our questions ready to put clearly to the electricians when the electricians are ready to answer us.

§ 9. It is possible that some of the loveliest conditions of these parallel clouds may be owing to a structure which I forgot to explain, when it occurred in rocks, in the course of the last volume.

When they are finely stratified, and their surfaces abraded by broad, shallow furrows, the edges of the beds, of course, are thrown into undulations, and at some distance, where the furrows disappear, the surface looks as if the rock had flowed over it in successive waves. Such a condition is seen on the left at the top in Fig. 17, in Vol. IV. Supposing a series of beds of vapor cut across by a straight sloping current of air, and so placed as to catch the light on their edges, we should have a series of curved lights, looking like independent clouds.

§ 10. I believe conditions of form like those in Fig. 82 (turn the book with its outer edge down) may not unfrequently be thus, owing to stratification, when they occur in the nearer sky. This line of cloud is far off at the horizon, drifting towards the left (the points of course forward), and is, I suppose, a series of nearly circular eddies seen in perspective.

Which question of perspective we must examine a little before going a step farther. In order to simplify it, let us assume that the under surfaces of clouds are flat, and lie in a horizontal extended field. This is in great measure the fact, and notable perspective phenomena depend on the approximation of clouds to such a condition.

§ 11. Referring the reader to my Elements of Perspective for statements of law which would be in this place tiresome, I can only ask him to take my word for it that the three figures in Plate 64 represent limiting lines of sky perspective, as they would appear over a large space of the sky. Supposing that the breadth included was one-fourth of the horizon, the shaded portions in the central figure represent square fields of cloud,[2] and those in the uppermost figure narrow triangles, with their shortest side next us, but sloping a little away from us.

In each figure, the shaded portions show the perspective limits of cloud-masses, which, in reality, are arranged in perfectly straight lines, are all similar, and are equidistant from each other. Their exact relative positions are marked by the lines connecting them, and may be determined by the reader if he knows perspective. If he does not, he may be surprised at first to be told that the stubborn and blunt little triangle, _b_, Fig. 1, Plate 64, represents a cloud precisely similar, and similarly situated, to that represented by the thin triangle, _a_; and, in like manner, the stout diamond, _a_, Fig. 2, represents precisely the same form and size of cloud as the thin strip at _b_. He may perhaps think it still more curious that the retiring perspective which causes stoutness in the triangle, causes leanness in the diamond.[3]

§ 12. Still greater confusion in aspect is induced by the apparent change caused by perspective in the direction of the wind. If Fig. 3 be supposed to include a quarter of the horizon, the spaces, into which its straight lines divide it, represent squares of sky. The curved lines, which cross these spaces from corner to corner, are precisely parallel throughout; and, therefore, two clouds moving, one on the curved line from _a_ to _b_, and the other on the other side, from _c_ to _d_, would, in reality, be moving with the same wind, in parallel lines. In Plate 66, which is a sketch of an actual sunset behind Beauvais cathedral (the point of the roof of the apse, a little to the left of the centre, shows it to be a summer sunset), the white cirri in the high light are all moving eastward, away from the sun, in perfectly parallel lines, curving a little round to the south. Underneath, are two straight ranks of rainy cirri, crossing each other; one directed south-east; the other, north-west. The meeting perspective of these, in extreme distance, determines the shape of the angular light which opens above the cathedral. Underneath all, fragments of true rain-cloud are floating between us and the sun, governed by curves of their own. They are, nevertheless, connected with the straight cirri, by the dark semi-cumulus in the middle of the shade above the cathedral.

§ 13. Sky perspective, however, remains perfectly simple, so long as it can be reduced to any rectilinear arrangement; but when nearly the whole system is curved, which nine times out of ten is the case, it becomes embarrassing. The central figure in Plate 65 represents the simplest possible combination of perspective of straight lines with that of curves, a group of concentric circles of small clouds being supposed to cast shadows from the sun near the horizon. Such shadows are often cast in misty air; the aspect of rays about the sun being, in fact, only caused by spaces between them. They are carried out formally and far in the Plate, to show how curiously they may modify the arrangement of light in a sky. The woodcut, Fig. 83, gives roughly the arrangement of the clouds in Turner's Pools of Solomon, in which he has employed a concentric system of circles of this kind, and thus lighted. In the perspective figure the clouds are represented as small square masses, for the sake of greater simplicity, and are so beaded or strung as it were on the curves in which they move, as to keep their distances precisely equal, and their sides parallel. This is the usual condition of cloud: for though arranged in curved ranks, each cloud has its face to the front, or, at all events, acts in some parallel line--generally another curve--with those next to it: being rarely, except in the form of fine radiating striæ, arranged on the curves as at _a_, Fig. 84; but as at _b_, or _c_. It would make the diagram too complex if I gave one of intersecting curves; but the lowest figure in Plate 65 represents, in perspective, two groups of ellipses arranged in equidistant straight and parallel lines, and following each other on two circular curves. Their exact relative position is shown in Fig. 2, Plate 56. While the uppermost figure in Plate 65 represents, in parallel perspective, a series of ellipses arranged in radiation on a circle, their exact relative size and position are shown in Fig. 3, Plate 56, and the lines of such a sky as would be produced by them, roughly, in Fig. 90, facing page 128.[4]

§ 14. And in these figures, which, if we look up the subject rightly, would be but the first and simplest of the series necessary to illustrate the action of the upper cirri, the reader may see, at once, how necessarily painters, untrained in observance of proportion, and ignorant of perspective, must lose in every touch the expression of buoyancy and space in sky. The absolute forms of each cloud are, indeed, not alike, as the ellipses in the engraving; but assuredly, when moving in groups of this kind, there are among them the same proportioned inequalities of relative distance, the same gradated changes from ponderous to elongated form, the same exquisite suggestions of including curve; and a common painter, dotting his clouds down at random, or in more or less equal masses, can no more paint a sky, than he could, by random dashes for its ruined arches, paint the Coliseum.

§ 15. Whatever approximation to the character of upper clouds may have been reached by some of our modern students, it will be found, on careful analysis, that Turner stands more absolutely alone in this gift of cloud-drawing, than in any other of his great powers. Observe, I say, cloud-_drawing_; other great men colored clouds beautifully; none but he ever drew them truly: this power coming from his constant habit of drawing skies, like everything else, with the pencil point. It is quite impossible to engrave any of his large finished skies on a small scale; but the woodcut, Fig. 85, will give some idea of the forms of cloud involved in one of his small drawings. It is only half of the sky in question, that of Rouen from St. Catherine's Hill, in the Rivers of France. Its clouds are arranged on two systems of intersecting circles, crossed beneath by long bars very slightly bent. The form of every separate cloud is completely studied; the manner of drawing them will be understood better by help of the Plate opposite, which is a piece of the sky above the "Campo Santo,"[5] at Venice, exhibited in 1842. It is exquisite in rounding of the separate fragments and buoyancy of the rising central group, as well as in its expression of the wayward influence of curved lines of breeze on a generally rectilinear system of cloud.

§ 16. To follow the subject farther would, however, lead us into doctrine of circular storms, and all kinds of pleasant, but infinite, difficulty, from which temptation I keep clear, believing that enough is now stated to enable the reader to understand what he is to look for in Turner's skies; and what kind of power, thought, and science are involved continually in the little white or purple dashes of cloud-spray, which, in such pictures as the San Benedetto, looking to Fusina, the Napoleon, or the Temeraire, guide the eye to the horizon more by their true perspective than by their aërial tone, and are buoyant, not so much by expression of lightness as of motion.[6]

§ 17. I say the "white or purple" cloud-spray. One word yet may be permitted me respecting the mystery of that color. What should we have thought--if we had lived in a country where there were no clouds, but only low mist or fog--of any stranger who had told us that, in his country, these mists rose into the air, and became purple, crimson, scarlet, and gold? I am aware of no sufficient explanation of these hues of the upper clouds, nor of their strange mingling of opacity with a power of absorbing light. All clouds are so opaque that, however delicate they may be, you never see one through another. Six feet depth of them, at a little distance, will wholly veil the darkest mountain edge; so that, whether for light or shade, they tell upon the sky as body color on canvas; they have always a perfect surface and bloom;--delicate as a rose-leaf, when required of them, but never poor or meagre in hue, like old-fashioned water-colors. And, if needed, in mass, they will bear themselves for solid force of hue against any rock. Facing p. 339, I have engraved a memorandum made of a clear sunset after rain, from the top of Milan cathedral. The greater part of the outline is granite--Monte Rosa--the rest cloud; but it and the granite were dark alike. Frequently, in effects of this kind, the cloud is darker of the two.[7] And this opacity is, nevertheless, obtained without destroying the gift they have of letting broken light through them, so that, between us and the sun, they may become golden fleeces, and float as fields of light.

Now their distant colors depend on these two properties together; partly on the opacity, which enables them to reflect light strongly; partly on a spongelike power of gathering light into their bodies.

§ 18. Long ago it was noted by Aristotle, and again by Leonardo, that vaporous bodies looked russet, or even red, when warm light was seen through them, and blue when deep shade was seen through them. Both colors may, generally, be seen on any wreath of cottage smoke.

Whereon, easy conclusion has sometimes been founded by modern reasoners. All red in sky is caused by light seen through vapor, and all blue by shade seen through vapor.

Easy, indeed, but not sure, even in cloud-color only. It is true that the smoke of a town may be of a rich brick red against golden twilight; and of a very lovely, though not bright, blue against shade. But I never saw crimson or scarlet smoke, nor ultramarine smoke.

Even granting that watery vapor in its purity may give the colors more clearly, the red colors are by no means always relieved against light. The finest scarlets are constantly seen in broken flakes on a deep purple ground of heavier cloud beyond, and some of the loveliest rose-colors on clouds in the east, opposite the sunset, or in the west in the morning. Nor are blues always attainable by throwing vapor over shade. Especially, you cannot get them by putting it over blue itself. A thin vapor on dark blue sky is of a warm gray, not blue. A thunder-cloud, deep enough to conceal everything behind it, is often dark lead-color, or sulphurous blue; but the thin vapors crossing it, milky-white. The vividest hues are connected also with another attribute of clouds, their lustre--metallic in effect, watery in reality. They not only reflect color as dust or wool would, but, when far off, as water would; sometimes even giving a distinct image of the sun underneath the orb itself;--in all cases becoming dazzling in lustre, when at a low angle, capable of strong reflection. Practically, this low angle is only obtained when the cloud seems near the sun, and hence we get into the careless habit of looking at the golden reflected light as if it were actually caused by nearness to the fiery ball.

§ 19. Without, however, troubling ourselves at all about laws, or causes of color, the visible consequences of their operation are notably these--that when near us, clouds present only subdued and uncertain colors; but when far from us, and struck by the sun on their under surfaces--so that the greater part of the light they receive is reflected--they may become golden, purple, scarlet, and intense fiery white, mingled in all kinds of gradations, such as I tried to describe in the chapter on the upper clouds in the first volume, in hope of being able to return to them "when we knew what was beautiful."

The question before us now is, therefore, What value ought this attribute of clouds to possess in the human mind? Ought we to admire their colors, or despise them? Is it well to watch them as Turner does, and strive to paint them through all deficiency and darkness of inadequate material? Or, is it wiser and nobler--like Claude, Salvator, Ruysdael, Wouvermans--never to look for them--never to portray? We must yet have patience a little before deciding this, because we have to ascertain some facts respecting the typical meaning of color itself; which, reserving for another place, let us proceed here to learn the forms of the inferior clouds.

FOOTNOTES:

[1] Before going farther, I must say a word or two respecting method
of drawing clouds.

Absolutely well no cloud _can_ be drawn with the point; nothing but
the most delicate management of the brush will express its variety of
edge and texture. By laborious and tender engraving, a close
approximation may be obtained either to nature or to good painting;
and the engravings of sky by our modern line engravers are often
admirable;--in many respects as good as can be, and to my mind the
best part of their work. There still exist some early proofs of
Miller's plate of the Grand Canal, Venice, in which the sky is the
likest thing to Turner's work I have ever seen in large engravings.
The plate was spoiled after a few impressions were taken off by
desire of the publisher. The sky was so exactly like Turner's that he
thought it would not please the public, and had all the fine
cloud-drawing rubbed away to make it soft.

The Plate opposite page 118, by Mr. Armytage, is also, I think, a
superb specimen of engraving, though in result not so good as the one
just spoken of, because this was done from my copy of Turner's sky,
not from the picture itself.

But engraving of this finished kind cannot, by reason of its
costliness, be given for every illustration of cloud form. Nor, if it
could, can skies be sketched with the completion which would bear it.
It is sometimes possible to draw one cloud out of fifty thousand with
something like fidelity before it fades. But if we want the
arrangement of the fifty thousand, they can only be indicated with
the rudest lines, and finished from memory. It was, as we shall see
presently, only by his gigantic powers of memory that Turner was
enabled to draw skies as he did.

Now, I look upon my own memory of clouds, or of anything else, as of
no value whatever. All the drawings on which I have ever rested an
assertion have been made without stirring from the spot; and in
sketching clouds from nature, it is very seldom desirable to use the
brush. For broad effects and notes of color (though these, hastily
made, are always inaccurate, and letters indicating the color do
nearly as well) the brush may be sometimes useful, but, in most
cases, a dark pencil, which will lay shade with its side and draw
lines with its point, is the best instrument. Turner almost always
outlined merely with the point, being able to remember the relations
of shade without the slightest chance of error. The point, at all
events, is needful, however much stump work may be added to it.

Now, in translating sketches made with the pencil point into
engraving, we must either engrave delicately and expensively, or be
content to substitute for the soft varied pencil lines the finer and
uncloudlike touches of the pen. It is best to do this boldly, if at
all, and without the least aim at fineness of effect, to lay down a
vigorous black line as the limit of the cloud form or action. The
more subtle a painter's finished work, the more fearless he is in
using the vigorous black line when he is making memoranda, of
treating his subject conventionally. At the top of page 224, Vol.
IV., the reader may see the kind of outline which Titian uses for
clouds in his pen work. Usually he is even bolder and coarser. And in
the rude woodcuts I am going to employ here, I believe the reader
will find ultimately that, with whatever ill success used by me, the
means of expression are the fullest and most convenient that can be
adopted, short of finished engraving, while there are some conditions
of cloud-action which I satisfy myself better in expressing by these
coarse lines than in any other way.

[2] If the figures are supposed to include less than one-fourth of
the horizon, the shaded figures represent diamond-shaped clouds; but
the reader cannot understand this without studying perspective laws
accurately.

[3] In reality, the retiring ranks of cloud, if long enough, would,
of course, go on converging to the horizon. I do not continue them,
because the figures would become too compressed.

[4] I use ellipses in order to make these figures easily
intelligible; the curves actually _are_ variable curves, of the
nature of the cycloid, or other curves of continuous motion; probably
produced by a current moving in some such direction as that indicated
by the dotted line in Fig. 3, Plate 56.

[5] Now in the possession of E. Bicknell, Esq., who kindly lent me
the picture, that I might make this drawing from it carefully.

[6] I cannot yet engrave these; but the little study of a single rank
of cirrus, the lowest in Plate 63, may serve to show the value of
perspective in expressing buoyancy. It is not, however, though
beautifully engraved by Mr. Armytage, as delicate as it should be, in
the finer threads which indicate increasing distance at the
extremity. Compare the rising of the lines of curve at the edges of
this mass, with the similar action on a larger scale, of Turner's
cloud, opposite.

[7] In the autobiography of John Newton there is an interesting
account of the deception of a whole ship's company by cloud, taking
the aspect and outline of mountainous land. They ate the last
provision in the ship, so sure were they of its being land, and were
nearly starved to death in consequence.