Part 11
An eighth motion, due to the action of the Moon on the equatorial swelling of the Earth, that of nutation, causes the pole of the equator to describe a small ellipse in eighteen years and eight months.
A ninth, due also to the attraction of our satellite, incessantly changes the position of the globe's centre of gravity and the Earth's place in space. When the Moon is in front of us, she accelerates the speed of the globe; when she is behind, she retards us, on the contrary, like a check-rein,--a monthly complication which is added to all the others.
When the Earth passes between the Sun and Jupiter, the attraction of the latter, in spite of its distance of 155,000,000 leagues, makes it deviate by 2 m. 10 sec. from its absolute orbit. The attraction of Venus makes it deviate 1 m. 25 sec. the other way. Saturn and Mars also act upon it, but more feebly. These are exterior disturbances, which make up a tenth kind of correction to add to the motion of our celestial barque.
The whole of the planets weigh about one seven hundredth part of the weight of the Sun; the centre of gravity around which the Earth annually turns is not in the very centre of the Sun, but far from the centre, and often even outside of the solar globe. Now, absolutely speaking, the Earth does not turn around the Sun; but the two heavenly bodies, Sun and Earth, turn about their common centre of gravity. Thus the centre of our planet's annual motion is constantly changing place, and we may add this eleventh complication to the others. We might even add many others to these; but the preceding ones are enough to make the degree of lightness and delicacy of our floating island appreciated, subject, as we have seen, to all the fluctuations of celestial influences. Mathematical analysis goes very far beyond this summary statement. It has found that the Moon alone, which seems to turn so peacefully about us, has more than sixty distinct motions.
The expression is therefore not exaggerated: our planet is but the plaything of the cosmic forces which accompany it in the meadows of the sky, and it is the same with everything existing in the universe. Matter is meekly obedient to force.
Where, then, is the fixed point which we desire for our support?
Our planet, then, formerly supposed to be at the base of the universe, is in fact kept up at a distance by the Sun, which makes the Earth gravitate about it with a speed corresponding to that distance. This speed, caused by the solar mass itself, keeps our planet at the same mean distance from the central star. A lesser speed would make the weight predominate, and would lead to the Earth's falling into the Sun; a greater speed, on the contrary, would progressively and infinitely send our planet away from its life-giving focus. But at the speed resulting from gravitation, our wandering home remains suspended in permanent stability, just as the Moon is upheld in space by the force of the Earth's gravity, which makes it circulate about the Earth with the speed requisite to maintain it constantly at the same mean distance. The Earth and the Moon thus form a planetary couple in space which sustain each other in perpetual equilibrium under the supreme domination of solar attraction. If the Earth existed alone in the universe, it would be forever motionless in the void, wherever it had been placed, with no power to descend or rise or change its position in any way whatsoever; these very expressions--to rise, descend, left or right--having no absolute sense whatever. If this same Earth, while existing alone, had received any impetus whatever, had been thrown with any speed in any direction, it would have whirled away forever in a straight line in that direction, never being able to stop or to slacken its pace or change its motion. It would have been the same thing if the Moon had existed alone with it; they would both have turned about their common centre of gravity, fulfilling their destiny in the same place in space, flying together, following the direction in which they had been thrown. The Sun existing and being the centre of its system, the Earth, all the planets and their satellites, are dependent upon it, and to it their destiny is irrevocably bound.
Is the fixed point that we are seeking, the solid base which we seem to need to insure the stability of the universe, to be found in that colossal and heavy globe, the Sun?
Assuredly not, since the Sun itself is not in repose, for it is bearing us and all its system away towards the constellation of Hercules.
Does our Sun gravitate around an immense sun whose attraction extends to it and controls its destinies as it controls that of the planets? Do investigations in sidereal astronomy lead us to believe that a star of such magnitude can exist in a direction situated at right angles with our course towards Hercules? No; our Sun is influenced by sidereal attraction, but no one star appears to overpower all the others and reign sovereign over our central star.
Although it may be perfectly admissible, or rather certain, that the sun nearest to ours, the star Alpha Centauri, and our own Sun feel their mutual attraction; although this star may be situated at about 90 degrees from our tangent towards Hercules, and, more than that, in the plane of the principal stars, passing by Perseus, Capella, Vega, Aldebaran, and the Southern Cross; and although the proper motion of this neighboring sun may be turned sensibly in the opposite direction from ours,--yet we could not consider these two systems as forming one couple analogous to that of the double stars; in the first place, because all the known double-star systems are composed of stars much nearer to each other, and then because in the immensity of the orbit described, according to this hypothesis, the attraction of the neighboring stars could not be considered as remaining without influence; and lastly, because the actual rates of speed with which these two suns are moved are much less great than those which would result from their mutual attraction.
The little constellation of Perseus, especially, might very well exert a more powerful action than that of the Pleiades, or than any other group of stars, and be the fixed point, the centre of gravity, of the motions of our Sun, of Alpha Centauri, and the neighboring stars, inasmuch as the cluster of Perseus is not only at right angles with the tangent of our movement towards Hercules, but also in the great circle of the principal stars and precisely at the intersection of this circle with the Milky Way. But here another factor comes in, of more importance than all the preceding ones,--this Milky Way, with its eighteen millions of suns, of which it would assuredly be audacious to seek the centre of gravity.
But what is the whole entire Milky Way, after all, compared with the milliards of stars which our mind contemplates in the bosom of the sidereal universe? Is not this Milky Way itself moving like an archipelago of floating islands? Is not every resolvable nebula, each cluster of stars, a Milky Way in motion under the action of the gravitation of other universes, which call to it and appeal to it through the infinite night?
* * * * *
Our thoughts are transported from star to star, from system to system, from region to region, in the presence of unfathomable grandeurs, in sight of celestial motions whose speed we are but just beginning properly to value, but which already surpasses all conception. The proper annual motion of the sun Alpha Centauri exceeds 188 millions of leagues per year. The proper motion of the 61st of Cygnus (second sun in the order of distances) is equivalent to 370 millions of leagues per year, or about one million of leagues per day. The star Alpha Cygni comes to us in a direct line at a speed of 500 millions of leagues per year. The proper motion of the star 1830 of Groombridge's Catalogue rises to 2,590 millions of leagues per year, which represents seven millions of leagues per day, 115,000 kilometres per hour, or 320,000 metres per second! These are minimum estimates, inasmuch as we certainly do not see perpendicularly, but obliquely, the stellar displacements thus measured.
What projectiles! They are suns thousands and millions of times heavier than the Earth, launched through the unfathomable void with giddy rates of speed, revolving in immensity under the influence of the gravitation of all the stars of the universe. And these millions and thousand millions of suns, planets, clusters of stars, nebulæ, worlds in their infancy, worlds near their end, rush with equal velocity towards goals of which they are ignorant, with an energy and intensity of action before which gunpowder and dynamite are like the breath of sleeping babes.
And thus everything hurries on through all eternity perhaps, without being able ever to reach the unexisting limits of infinity.... Motion, activity, light, life everywhere. Happily so, without doubt. If all these innumerable suns, planets, earths, moons, comets, were fixed and immovable, petrified kings in their eternal tombs, how much more formidable, but also more mournful, would be the aspect of such a universe! Can you imagine the whole creation stopped, benumbed, mummified? Is not such an idea unbearable? Is there not something funereal about it?
What causes these motions? What maintains them? What regulates them? Universal gravitation, invisible force, which the visible universe (what we call matter) obeys. A body attracted from infinity by the Earth would attain a velocity of 11,300 metres per second; just as a body thrown from the Earth with that speed would never fall again. A body attracted by the Sun from the infinite would attain a speed of 608,000 metres; and a body thrown by the Sun with that swiftness would never return to its point of departure. Clusters of stars may give us velocities much more remarkable still, but which are explained by the theory of gravitation. A glance at a map of the proper motions of the stars is enough to make one understand the variety and grandeur of these motions.
* * * * *
Thus the stars, the suns, the planets, the worlds, the shooting-stars, the meteoric stones, in short all the bodies which constitute this vast universe, rest, not on solid bases, as the childish and primitive conception of our fathers seemed to require, but _upon invisible and immaterial forces_ which govern their motions. These milliards of celestial bodies have their respective movements for the purpose of stability, and mutually lean upon each other across the void which separates them. The mind which could eliminate time and space would see the Earth, the planets, the Sun, the stars, rain down from a limitless sky in all imaginable directions, like the drops carried away by the whirlwinds of a gigantic tempest, and drawn, not by a common basis, but by the attraction of each and all; each one of these cosmic drops, each one of these worlds, each one of these suns, is whirled away at a speed so rapid that the flight of cannon-balls is but rest in comparison: it is not one hundred, nor five hundred, nor a thousand metres per second,--it is ten thousand, twenty, fifty, a hundred, and even two or three hundred thousand metres _per second_!
How is it that there are no meetings in the midst of all this motion? Perhaps there may be some,--the "temporary stars," which appear to rise again from their ashes, would seem to indicate it. But as a matter of fact, it would be difficult for meetings to occur, because space is immense, relatively to the celestial bodies, and because the motion by which each body is animated entirely prevents it from submitting passively to the attraction of another body and falling upon it; it keeps its own motion, which cannot be destroyed, and glides around the focus which attracts it, as a butterfly would obey the attraction of a flame without burning itself in it. Besides, absolutely speaking, these motions are not "rapid."
Indeed, everything runs, flies, falls, rolls, rushes through the void, but at such respective distances that it all appears to be at rest. If we wanted to place in a frame, the size of Paris, the stars whose distances have been measured up to the present time, the nearest star would be placed at two kilometres from the Sun, from which the Earth would be distant one centimetre, Jupiter at five centimetres, and Neptune at thirty centimetres. The 61st of Cygnus would be at four kilometres, Sirius at ten kilometres, the polar star at twenty-seven kilometres, etc.; and the immense majority of the stars would remain outside the department of the Seine. Well, to give to all these projectiles their relative motions, the Earth would take a year to run through its orbit of a centimetre radius, Jupiter twelve years to run through his of five centimetres, and Neptune one hundred and sixty-five years. The proper motions of the Sun and stars would be of the same nature; that is to say, all would appear to be at rest, even under the microscope. Urania reigns with calmness and serenity in the immensity of the universe.
So the constitution of the sidereal universe is just like that of the bodies which we call material. All bodies, organic or inorganic, man, animal, plant, stone, iron, bronze, are composed of molecules which are in perpetual motion, and which do not touch one another. Each one of these atoms is infinitely small, and invisible not only to the eye, not only to the microscope, but even to thought; since it is possible that these atoms may be centres of force. It has been calculated that in the head of a pin there are not less than eight sextillions of atoms,--that is, eight thousand milliards of milliards,--and that in one centimetre of cubic air there are not less than a sextillion of molecules. All these atoms, all these molecules, are in motion under the influence of the forces which govern them; and as compared with their dimensions, great distances separate them. We may even believe that there is in principle but one kind of atoms, and that it is the number of primitive atoms, essentially simple and homogeneous, their modes of arrangement, and their motions, which constitute the diversity of molecules; a molecule of gold, of iron, would not differ from a molecule of sulphur, of oxygen, of hydrogen, etc., except in the number, the disposition, and the motion of the primitive atoms which compose it: each molecule would be a system, a microcosm.
But whatever may be the idea that one conceives of the inner constitution of bodies, the truth is now recognized and indisputable that the fixed point for which our imagination has been seeking, exists nowhere. Archimedes can vainly call for a point of support, that he may lift the world. _Worlds, like atoms, rest on the invisible_, on immaterial force; everything moves, urged on by attraction, and as if in search of that fixed point which flies as it is pursued, and which does not exist, since in the infinite the centre is everywhere and nowhere. So-called positive minds, which assert with so much assurance that "Matter reigns alone, with its properties," and who smile disdainfully at the researches of thinkers, should first tell us what they mean by that famous word "matter." If they did not stop at the surface of things, if they even suspected that appearances hid intangible realities, they would doubtless be a little more modest.
To us, who seek the truth with no jealousy of system, it seems that the essence of matter remains as mysterious as the essence of force; the visible universe not being in the least what it appears to be to our senses. In fact, that visible universe is composed of invisible atoms; it rests upon the void, and the forces which govern it are in themselves immaterial and invisible. It would be less bold to think that matter does not exist, that all is dynamism, than to pretend to affirm the existence of an exclusively material universe. As to the material support of the world, it disappeared--a somewhat interesting observation--precisely with the conquest of Mechanics, which proclaim the triumph of the invisible. The fixed point vanishes in the universal balance of powers, in the ideal harmony of ether vibrations; the more one seeks it, the less one finds it; and the last effort of our thought has for a last support, for supreme reality, the Infinite.
A SOUL CLOTHED WITH AIR.
She was standing, in her chaste nudity, with uplifted arms, twisting the thick and waving masses of her hair, which she was trying to bring into subjection on the top of her head,--a fresh, young beauty, who had not yet attained the fulness and perfection of developed form, but was approaching it, radiant in the loveliness of her seventeenth year.
A child of Venice, her white, soft, rose-tinted skin revealed the circulation of a strong and ardent life-blood beneath its transparency; her eyes shone with a mysterious and haunting light, and the dewy redness of her lightly parted lips made one think of the fruit as much as of the flower. She was marvellously beautiful as she stood thus; and if some hero Paris had received a mission to award the palm to her, I do not know which he would have laid at her feet, that of grace, elegance, or beauty,--for she seemed to blend the living charm of modern attractiveness with the calm perfections of classic beauty.
The happiest, the most unexpected chance had led the painter Falero and me to where she was. One lovely afternoon last spring we were walking on the seashore. We had been through one of the groves of olive-trees, with their sad-looking leaves, which are so frequent between Nice and Monaco, and without being aware of it had entered some private grounds which were unenclosed on the side towards the beach. A picturesque, winding path led up the hill. We had just passed an orange-grove whose golden apples recalled the garden of the Hesperides; the air was fragrant, the sky a deep blue, and we were discoursing upon a parallel between art and science, when my companion suddenly stopped, as if by an irresistible fascination, making me a sign to be silent and to look.
Behind the clumps of cactus and fig-trees, a few feet in front of us, was a sumptuous bathroom, with its western window open, letting us see the young girl standing not far from a marble basin into which a jet of water fell with a gentle murmur, and before a large mirror which reflected her image from head to foot. Probably the noise of the falling water had prevented her hearing our footsteps. We stood mute and motionless behind the cactus, discreetly, or indiscreetly, watching her. She was lovely, and apparently unaware of her own beauty. Her feet were on a tiger-skin; she was in no haste. Finding that her hair was still too damp, she let it fall about her again, turned in our direction, and picked up a rose from the table near the window; then going back to the long mirror, she resumed her hair-dressing, finished it leisurely, put the little rose between two coils, and turning with her back to the sun, stooped, probably to pick up her first piece of clothing. But she suddenly sprang back with a piercing cry, hid her face in her hands, and hastily retreated to a shaded corner.
We have always thought since that some movement of our heads must have betrayed our presence, or that by some trick of the mirror she had seen us. Whatever it was, we thought it prudent to retrace our steps, and went down to the sea again by the same path.
* * * * *
"Ah," said my companion, "I assure you that among all my models I have never seen any more perfect, even for my picture of the 'Double Stars' and of 'Celia.' What do you think about it yourself? Did not that apparition come just in time to prove that I am right? You need waste no eloquence upon the delights of science,--acknowledge that art also has its charms. Do not the stars of Earth compare favorably with the beauties of the sky? Do you not admire the graceful beauty of that form as I do? What exquisite tints, what flesh!"
"I should not have the bad taste not to admire what is truly beautiful," I answered. "I admit that human beauty (and of course female loveliness in particular) truly represents the most perfect thing that Nature has produced on our planet. But do you know what I most admire in that being? It is not its artistic or æsthetic aspect, it is the scientific proof it gives of a simply wonderful fact. In that beautiful body I see a soul clothed with air."
"Oh, you are fond of paradoxes! A soul clothed with air! That is rather idealistic for so real a body! No doubt the charming creature has a soul; but permit an artist to admire her body, her vitality, her solidity, her color...."
"I do not object. But it is just that physical beauty which makes me admire the soul in her, the invisible force that formed her."
"What do you mean by that? We surely have a body! The existence of a soul is less palpable."
"To the senses, yes; to the mind, no. Now, your senses absolutely deceive you about the motion of the Earth, the nature of the sky, the apparent solidity of the body; about beings and about things. Will you follow my reasoning for a moment?
* * * * *
"When I breathe the perfume of a rose, when I admire the beauty of form, the smoothness of coloring, the grace of this flower in its freshly opening bloom, what strikes me most is the work of the hidden, unknown, mysterious force which rules over the plant's life and can direct it in the maintenance of its existence, which chooses the proper molecules of air, water, and earth for its nourishment, and which knows above all how to assimilate those molecules and group them so delicately as to form this graceful stem, these dainty little green leaves, these soft pink petals, these exquisite tints and delicious fragrance. This mysterious force is the animating principle of the plant. Put a lily-seed, an acorn, a grain of wheat, and a peach-stone side by side in the ground; each germ will build up its own organism.
"I knew a maple-tree which was dying on the ruins of an old wall, a few feet from good, rich soil in a ditch, and which in despair threw out a venturesome root, reached the coveted soil, buried itself there, and gained a solid footing, so that by degrees, although a motionless thing, it changed its place, let its original roots die, left the stones, and lived resuscitated upon the organ that had set it free. I have known elms which were going to eat up the soil of a fertile field, whose food had been cut off from them by a wide ditch, and who therefore determined to make their uncut roots pass under the ditch. They succeeded, and returned to their regular food, much to the cultivator's astonishment. I knew an heroic jasmine which went eight times through holes in a board which kept the light away from it, and which a teasing observer would put back into the shade, hoping at last to wear out the flower's energy; but he did not succeed.
"A plant breathes, drinks, eats, selects, refuses, seeks, works, lives, acts according to its instincts. One does 'like a charm,' another pines, a third is nervous and agitated. The sensitive-plant shivers and droops its leaves at the slightest touch. In certain hours of well-being the calla lily is warm, the pink is phosphorescent, the valisneria goes down to the bottom of the lake to ripen the fruit of her loves. In these manifestations of an unknown life the philosopher cannot help recognizing a song from the universal choir in the plant world.