The Storm-Cloud of the Nineteenth Century Part 4

Nothing irritates me more, myself, than having the color of my own descriptions of phenomena in anywise attributed by the reader to accidental states either of my mind or body;--but I cannot, for once, forbear at least the innocent question to Professor Tyndall, whether the extreme beauty of these 'interference spectra' may not have been partly owing to the extreme _sobriety_ of the observer?

no refreshment, it appears, having been attainable the night before at the Grands Mulets, except the beverage diluted with dirty snow, of which I have elsewhere quoted the Professor's pensive report,--"my memory of that tea is not pleasant."]

[Footnote 16: 'Either stationary or slow in motion, reflecting unresolved light.'

The rate of motion is of course not essentially connected with the method of illumination; their connection, in this instance, needs explanation of some points which could not be dealt with in the time of a single lecture.

It is before said, with reserve only, that "a cloud is where it is seen, and is not where it is not seen." But thirty years ago, in 'Modern Painters,' I pointed out (see the paragraph quoted in note 8th), the extreme difficulty of arriving at the cause of cloud outline, or explaining how, if we admitted at any given moment the atmospheric moisture to be generally diffused, it could be chilled by formal _chills_ into formal clouds. How, for instance, in the upper cirri, a thousand little chills, alternating with a thousand little warmths, could stand still as a thousand little feathers.

But the first step to any elucidation of the matter is in the firmly fixing in our minds the difference between windless clouds, unaffected by any conceivable local accident, and windy clouds, affected by some change in their circ.u.mstances as they move.

In the sunset at Abbeville, represented in my first diagram, the air is absolutely calm at the ground surface, and the motion of its upper currents extremely slow. There is no local reason a.s.signable for the presence of the cirri above, or of the thundercloud below.

There is no conceivable cause either in the geology, or the moral character, of the two sides of the town of Abbeville, to explain why there should be decorative fresco on the sky over the southern suburb, and a muttering heap of gloom and danger over the northern.

The electric cloud is as calm in motion as the harmless one; it changes its forms, indeed; but imperceptibly; and, so far as can be discerned, only at its own will is exalted, and with its own consent abased.

But in my second diagram are shown forms of vapor sustaining at every instant all kinds of varying local influences; beneath, fastened down by mountain attraction, above, flung afar by distracting winds; here, spread abroad into blanched sheets beneath the suns.h.i.+ne, and presently gathered into strands of coiled cordage in the shade. Their total existence is in metamorphosis, and their every aspect a surprise, or a deceit.]

[Footnote 17: 'Finely comminuted water or _ice_.'

My impression that these clouds were glacial was at once confirmed by a member of my audience, Dr. John Rae, in conversation after the lecture, in which he communicated to me the perfectly definite observations which he has had the kindness to set down with their dates for me, in the following letter:--

"4, ADDISON GARDENS, KENSINGTON, _4th Feb., 1884._

DEAR SIR,--I have looked up my old journal of thirty years ago, written in pencil because it was impossible to keep ink unfrozen in the snow-hut in which I pa.s.sed the winter of 1853-4, at Repulse Bay, on the Arctic Circle.[A]

On the 1st of February, 1854, I find the following:--

'A beautiful appearance of some cirrus clouds near the sun, the central part of the cloud being of a fine pink or red, then green, and pink fringe. This continued for about a quarter of an hour. The same was observed on the 27th of the month, but not so bright.

Distance of clouds from sun, from 3 to 6.'

On the 1st February the temperature was 38 below zero, and on the 27th February 26 below.

'On the 23d and 30th (of March) the same splendid appearance of clouds as mentioned in last month's journal was observed. On the first of these days, about 10.30 a.m., it was extremely beautiful.

The clouds were about 8 or 10 from the sun, below him and slightly to the eastward,--having a green fringe all round, then pink; the center part at first green, and then pink or red.'

The temperature was 21 below zero, Fahrenheit.

There may have been other colors--blue, perhaps--but I merely noted the most prominent; and what I call green may have been bluish, although I do not mention this last color in my notes.

From the lowness of the temperature at the time, the clouds _must_ have been frozen moisture.

The phenomenon is by no means common, even in the Arctic zone.

The second beautiful cloud-picture shown this afternoon brought so visibly to my memory the appearance seen by me as above described, that I could not avoid remarking upon it.

Believe me very truly yours, JOHN RAE." (M.D., F.R.S.)

Now this letter enables me to leave the elements of your problem for you in very clear terms.

Your sky--altogether--may be composed of one or more of four things:--

Molecules of water in warm weather.

Molecules of ice in cold weather.

Molecules of water-vapor in warm weather.

Molecules of ice-vapor in cold weather.

But of the size, distances, or modes of attraction between these different kinds of particles, I find no definite information anywhere, except the somewhat vague statement by Sir William Thomson, that "if a drop of water could be magnified so as to be as large as the earth, and have a diameter of eight thousand miles, then a molecule of this water in it would appear _somewhat larger than a shot_." (What kind of shot?) "_and somewhat smaller than a cricket-ball_"!

And as I finally review the common accounts given of cloud formation, I find it quite hopeless for the general reader to deal with the quant.i.ty of points which have to be kept in mind and severally valued, before he can account for any given phenomena. I have myself, in many of the pa.s.sages of 'Modern Painters' before referred to, conceived of cloud too narrowly as always produced by _cold_, whereas the temperature of a cloud must continually, like that of our visible breath in frosty weather, or of the visible current of steam, or the smoking of a warm lake surface under sudden frost, be above that of the surrounding atmosphere; and yet I never remember entering a cloud without being chilled by it, and the darkness of the plague-wind, unless in electric states of the air, is always accompanied by deadly chill.

Nor, so far as I can read, has any proper account yet been given of the balance, in serene air, of the warm air under the cold, in which the warm air is at once compressed by weight, and expanded by heat, and the cold air is thinned by its elevation, yet contracted by its cold. There is indeed no possibility of embracing the conditions in a single sentence, any more than in a single thought.

But the practical balance is effected in calm air, so that its lower strata have no tendency to rise, like the air in a fire balloon, nor its higher strata to fall, unless they congeal into rain or snow.

I believe it will be an extreme benefit to my younger readers if I write for them a little 'Grammar of Ice and Air,' collecting the known facts on all these matters, and I am much minded to put by my ecclesiastical history for a while, in order to relate what is legible of the history of the visible Heaven.

[Footnote A: I trust that Dr. Rae will forgive my making the reader better aware of the real value of this communication by allowing him to see also the following pa.s.sage from the kind private letter by which it was supplemented:--

"Many years in the Hudson's Bay Company's service, I and my men became educated for Arctic work, in which I was five different times employed, in two of which expeditions we lived wholly by our own hunting and fis.h.i.+ng for twelve months, once in a stone house (very disagreeable), and another winter in a snow hut (better), _without fire of any kind to warm us_. On the first of these expeditions, 1846-7, my little party, there being no officer but myself, surveyed seven hundred miles of coast of Arctic America by a sledge journey, which Parry, Ross, Bach, and Lyon had failed to accomplish, costing the country about 70,000 or 80,000 at the lowest computation. The total expense of my little party, including my own pay, was under fourteen hundred pounds sterling.

"My Arctic work has been recognized by the award of the founder's gold medal of the Royal Geographical Society (before the completion of the whole of it)."]]

[Footnote 18: 'You can't get a billiard ball to fall a s.h.i.+vering on its own account.'--I am under correction in this statement by the Lucasian professor of Cambridge, with respect to the molecules of bodies capable of 'epipolizing' light. "Nothing seems more natural than to suppose that the incident vibrations of the luminiferous ether produce vibratory movements among the ultimate molecules of sensitive substances, and that the molecules in return, _swinging on their own account_, produce vibrations in the luminous ether, and thus cause the sensation of light. The periodic times of these vibrations depend upon the periods in which the molecules are _disposed to swing_." ('On the Changes of Refrangibility of Light,'

p. 549.)

It seems to me a pleasant conclusion, this, of recent science, and suggestive of a perfectly regenerate theology. The 'Let there be light' of the former Creation is first expanded into 'Let there be a disposition of the molecules to swing,' and the destinies of mankind, no less than the vitality of the universe, depend thereafter upon this amiable, but perhaps capricious, and at all events not easily influenced or antic.i.p.ated, disposition!

Is it not also strange that in a treatise entering into so high mathematical a.n.a.lysis as that from which I quote, the false word 'swing,' expressing the action of a body liable to continuous arrest by gravitation, should be employed to signify the oscillation, wholly unaffected by gravity, of substance in which the motion once originated, may cease only with the essence of the body?

It is true that in men of high scientific caliber, such as the writer in this instance, carelessness in expression does not affect the security of their conclusions. But in men of lower rank, mental defects in language indicate fatal flaws in thought. And although the constant habit to which I owe my (often foolishly praised) "command of language"--of never allowing a sentence to pa.s.s proof in which I have not considered whether, for the vital word in it, a better could be found in the dictionary, makes me somewhat morbidly intolerant of careless diction, it may be taken for an extremely useful and practical rule, that if a man can think clearly he will write well, and that no good science was ever written in bad English. So that, before you consider whether a scientific author says a true or a false thing, you had better first look if he is able properly to say _any_thing,--and secondly, whether his conceit permits him to say anything properly.

Thus, when Professor Tyndall, endeavoring to write poetically of the sun, tells you that "The Lilies of the field are his workmans.h.i.+p," you may observe, first, that since the sun is not a man, nothing that he does is workmans.h.i.+p; while even the figurative statement that he rejoices _as_ a strong man to run his course, is one which Professor Tyndall has no intention whatever of admitting.

And you may then observe, in the second place, that, if even in that figurative sense, the lilies of the field are the sun's workmans.h.i.+p, in the same sense the lilies of the hothouse are the stove's workmans.h.i.+p,--and in perfectly logical parallel, you, who are alive here to listen to me, because you have been warmed and fed through the winter, are the workmans.h.i.+p of your own coal-scuttles.

Again, when Mr. Balfour Stewart begins a treatise on the 'Conservation of Energy,' which is to conclude, as we shall see presently, with the prophecy of its total extinction as far as the present world is concerned,--by clothing in a "properly scientific garb," our innocent impression that there is some difference between the blow of a rifle stock and a rifle ball; he prepares for the scientific toilet by telling us in italics that "the something which the rifle ball possesses in contradistinction to the rifle stock is clearly the power of overcoming resistance," since "it can penetrate through oak-wood or through water--or (alas! that it should be so often tried) through the human body; and _this power of penetration_" (italics now mine) "_is the distinguis.h.i.+ng characteristic of a substance moving with very great velocity_. Let us define by the term 'Energy,' this power which the rifle ball possesses of overcoming obstacles, or of doing work."

Now, had Mr. Stewart been a better scholar, he would have felt, even if he had not known, that the Greek word 'energy' could only be applied to the living--and of living, with perfect propriety only to the _mental_, action of animals, and that it could no more be applied as a 'scientific garb,' to the flight of a rifle ball, than to the fall of a dead body. And, if he had attained thus much, even of the science of language, it is just possible that the small forte and faculty of thought he himself possesses might have been energized so far as to perceive that the force of all inertly moving bodies, whether rifle stock, rifle ball, or rolling world, is under precisely one and the same relation to their weights and velocities; that the effect of their impact depends--not merely on their pace, but their const.i.tution; and on the relative forms and stability of the substances they encounter, and that there is no more quality of Energy, though much less quality of Art, in the swiftly penetrating shot, or crus.h.i.+ng ball, than in the deliberately contemplative and administrative puncture by a gnat's proboscis, or a seamstress' needle.

Mistakes of this kind, beginning with affectations of diction, do not always invalidate general statements or conclusions,--for a bad writer often equivocates out of a blunder as he equivocates into one,--but I have been strict in pointing out the confusions of idea admitted in scientific books between the movement of a swing, that of a sounding violin chord, and that of an agitated liquid, because these confusions have actually enabled Professor Tyndall to keep the scientific world in darkness as to the real nature of glacier motion for the last twenty years; and to induce a resultant quant.i.ty of aberration in the scientific mind concerning glacial erosion, of which another twenty years will scarcely undo the damage.]

[Footnote 19: 'Force and pace.'--Among the nearer questions which the careless terminology on which I have dwelt in the above note has left unsettled, I believe the reader will be surprised, as much as I am myself, to find that of the mode of impulse in a common gust of wind! Whence is its strength communicated to it, and how gathered in it? and what is the difference of manner in the impulse between compressible gas and incompressible fluid? For instance: The water at the head of a weir is pa.s.sing every instant from slower into quicker motion; but (until broken in the air) the fast flowing water is just as dense as the slowly flowing water. But a fan alternately compresses and rarefies the air between it and the cheek, and the violence of a destructive gust in a gale of wind means a momentary increase in velocity and density of which I cannot myself in the least explain,--and find in no book on dynamics explained,--the mechanical causation.

The following letter, from a friend whose observations on natural history for the last seven or eight years have been consistently valuable and instructive to me, will be found, with that subjoined in the note, in various ways interesting; but especially in its notice of the inefficiency of ordinary instrumental registry in such matters:--

"6, MOIRA PLACE, SOUTHAMPTON, _Feb. 8th, 1884_.

DEAR MR. RUSKIN,--Some time since I troubled you with a note or two about sea-birds, etc.... but perhaps I should never have ventured to trouble you again, had not your lecture on the 'Storm Clouds'

touched a subject which has deeply interested me for years past. I had, of course, no idea that you had noticed this thing, though I might have known that, living the life you do, you must have done so. As for me, it has been a source of perplexity for years: so much so, that I began to wonder at times whether I was not under some mental delusion about it, until the strange theatrical displays, of the last few months, for which I was more or less prepared, led so many to use their eyes, unmuzzled by bra.s.s or gla.s.s, for a time. I know you do not bother, or care much to read newspapers, but I have taken the liberty of cutting out and sending a letter of mine, sent on the 1st January to an evening paper,[A] upon this subject, thinking you might like to know that one person, at any rate, has seen that strange, bleared look about the sun, s.h.i.+ning so seldom except through a ghastly glare of pale, persistent haze. May it be that the singular coloring of the sunsets marks an end of this long period of plague-cloud, and that in them we have promise of steadier weather? (No: those sunsets were entirely distinct phenomena, and promised, if anything, only evil.--R.)

I was glad to see that in your lecture you gave the dependants upon the instrument-makers a warning. On the 26th I had a heavy sailing-boat lifted and blown, from where she lay hauled up, a distance of four feet, which, as the boat has four hundred-weight of iron upon her keel, gives a wind-gust, or force, not easily measured by instruments.