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The Atlantic Monthly, Volume 04, No. 26, December, 1859
This seems almost too wonderful for belief, and yet the proof is incontestable. However, the fact being established that the currents from the aurora borealis do have a direct effect upon the telegraph-wires, and that the currents are of both kinds, positive and negative,—as I have shown in my remarks upon the aurora of 1852, which sometimes left a dark line upon the prepared paper, and at other times bleached it,—it is a natural consequence that the wires should work better without batteries than with them, whenever a current from the aurora has sufficient intensity to neutralize the current from the batteries.
I will try to make myself clear upon this point. It makes no difference, in working the Morse, or any other system of magnetic telegraph, whether we have the positive or the negative pole to the line; but, whichever way we point, the same direction must be continued with all additional batteries we put upon the line. Now if we put a battery upon the line at Boston, of, say, twenty-five cells, and point the positive pole eastward, and the same number of cells at Portland, pointing the positive pole westward, the current will be null, that is to say, each will neutralize the other. Now the aurora, in presenting its positive pole, we will say, increases the current upon the line beyond the power of the magnet-keeper-spring to control it, and thus prevents the line from working, by surfeiting it with the electric current; until, presently, the wave recedes and is followed by a negative current which neutralizes the battery current, and prevents the line from working for want of power. It is plain, therefore, that, if the batteries be taken off, the positive current of the aurora cannot increase nor the negative decrease the working state of the line to the same extent as when the batteries are connected; but that, whichever pole is presented, the magnetism can be made use of by the operator for the ordinary duties of the line.
At Springfield, a gentleman who observed the needle of the compass, during the auroral display of August 28th, noticed that it was deflected first to the west, and then to the east, while the waves of the aurora were in motion. The electrotype plates at the office of the "Republican" at that place were so seriously affected by the aurora, that they could not be printed from during the continuance of the phenomenon.
The aurora borealis of August 28th was surpassingly brilliant not only in the northern portion of this continent, but also as far south as the equator,—as well as in Cuba, Jamaica, California, and the greater portion of Europe. The London newspapers of the 29th contain glowing descriptions of it. A California journal says:—"During the last ten years the aurora borealis was never seen in California except on very rare occasions, and then the light was very faint or barely visible; but on the 28th ult., it appeared in wonderful splendor,—the whole northern part of the sky being of a bright crimson; and the same phenomenon, with equal magnificence, was repeated on the night of the first instant."
In Jamaica the aurora borealis was witnessed for the first time, perhaps, since the discovery of this island by Columbus. So rare is the phenomenon in those latitudes, that it was taken for the glare of a fire, and was associated with the recent riots.
Mr. E.B. Elliot of Boston, in an interesting article upon the recent aurora, points out the simultaneous occurrence of the auroral display of February 19th, 1852, with the eruption of Mauna Loa,—the largest volcano in the world, situated on Hawaii, (one of the Sandwich Island group,)—on the 20th of February; on which occasion, the side of the mountain gave way about two-thirds of the distance from the base, giving passage to a magnificent stream of lava, five hundred feet deep and seven hundred broad.
Again, on the 17th of December, 1857, between the hours of one and four in the morning, there occurred an aurora of unwonted magnificence. The first steamer arriving from Europe after that date brought the following intelligence, which is taken from one of the journals of the day:—"An earthquake took place on the night of the 17th, throughout the whole kingdom of Naples, but its effects were most severe in the towns of Salerno, Potenza, and Nola. At Salerno, the walls of the houses were rent from top to bottom. Numerous villages were half destroyed."
Were these coincidences of extraordinary auroras with extraordinary commotions in the physical condition of our globe merely accidental? or are these phenomena due to a common cause? The latter supposition is not improbable, but the question can be fully settled only by further observations.
Mr. Meriam, "the sage of Brooklyn," as the daily journals denominate him, considers the aurora as the result of earthquakes or volcanic eruptions. He also says:—"The auroral light sometimes is composed of threads, like the silken warp of a web; these sometimes become broken and fall to the earth, and possess exquisite softness and a silvery lustre, and I denominate them the products of the silkery of the skies. I once obtained a small piece, which I preserved."
It is due to Mr. Meriam, as well as to the scientific world, to say, that he stands alone in his convictions with regard to the aurora, both in respect of the cause and the effect of the phenomenon.
Having thus illustrated the effects of the aurora, let us now return to the discussion of its causes.
The intimate and constant connection between the phenomena of the aurora borealis and terrestrial magnetism led Humboldt to class under the head of Magnetic Storms all disturbances in the equilibrium of the earth's magnetic forces. The presence of such storms is indicated by the oscillations of the magnetized needle, the disturbance of the currents upon the telegraph-wires, and the appearance of the aurora, of which these oscillations and disturbances are, as it were, the forerunners, and which itself puts an end to the storm,—as in electric storms the phenomenon of lightning announces that, the electrical equilibrium, temporarily disturbed, is now restored.
The atmosphere is constantly charged with positive electricity,—electricity furnished by the vapors that rise from the sea, especially in tropical regions,—and, on the other hand, the earth is negatively electrized. The recomposition or neutralization of the two opposite electricities of the atmosphere and of the terrestrial globe is brought about by means of the moisture with which the lower strata of the air are more or less charged. But it is especially in the polar regions, where the eternal ice that reigns there constantly condenses the aqueous vapors under the form of haze, that this recomposition must be brought about; the more so, as the positive vapors are carried thither and accumulated by the tropical current, which, setting out from the equatorial regions, where it occupies the most elevated regions of the atmosphere, descends as it advances towards the higher latitudes, until it comes in contact with the earth in the neighborhood of the poles. It is there, then, chiefly, that the equilibrium between the positive electricity of the vapors and the negative electricity of the earth must be accomplished by means of a discharge, which, when of sufficient intensity, will be accompanied with light, if, as is almost always the case near the poles, and sometimes in the higher parts of the atmosphere, it take place among those extremely small icy particles which constitute the hazes and the very elevated clouds.
There can be no doubt that the occurrence of the phenomenon is materially dependent on the presence in the atmosphere of these particles of ice, forming a kind of thin haze, which, becoming luminous by the transmission of electricity, must appear simply as an illuminated surface of greater or less extent, and more or less cut up. The phenomenon actually takes place in this manner in the parts of the atmosphere that are the most distant from the earth. We perceive what are termed auroral plates of a purple or reddish-violet color, more or less extended, according as this species of veil, formed by icy particles, extends to a greater or less distance from the poles. The tenuity of this veil is such that it admits of our seeing the stars through the auroral plates. Of its existence, independently of indirect proofs, we have a direct demonstration in the observation of MM. Bixio and Baral, who, being raised in a balloon to a great height, found themselves, on a sudden, although the sky was entirely serene and the atmosphere cloudless, in the midst of a perfectly transparent veil, formed by a multitude of little icy needles, so fine that they were scarcely visible.
If we place the pole of an electro-magnet over the jets of electric light that are made to converge in extremely rarefied air, we shall see that the electric light, instead of coming out indifferently from all points of the upper surface, as had taken place before the magnetization, comes out from the points of the circumference only of this surface, so as to form around it a continuous luminous ring. This ring possesses a movement of rotation around the magnetized cylinder, sometimes in one direction, sometimes in another, according to the direction of the discharge and of the magnetization. Finally, some more brilliant jets seem to come out from this luminous circumference without being confounded with the rest of the group. Now the magnetic pole exercises over the luminous haze which we have mentioned as always present during an aurora precisely the same action which the pole of the electro-magnet exercises in the experiment just described; and what takes place on the small scale of the experiment is precisely what takes place on the large scale of the phenomenon of the aurora borealis.
The arc of the aurora borealis is a portion of a luminous ring, the different points of which are sensibly at equal distances from the earth, and which centres upon the boreal magnetic pole, so as to cut at right angles all the magnetic meridians that converge towards this pole. Such a ring, seen by an observer placed at the surface of the earth, evidently presents to him the known arc of the aurora; and its apparent summit is always necessarily situated in the magnetic meridian of the place.
The diameter of the luminous ring is greater in proportion as the magnetic pole is more distant from the surface of the earth, since this pole must be situated upon the intersection of the plane of the ring with the axis of the terrestrial globe; if we could determine rigorously the position of the aurora borealis, we should then have the means of knowing exactly that of the pole itself.
Each observer sees the summit of the auroral arc at his magnetic meridian; it is, therefore, only those who are on the same magnetic meridian who see the same summit, and who are able by simultaneous observations to take its height.
If the summit of the arc pass beyond the zenith of the observer, the latter is surrounded by the matter of the aurora borealis. This matter is nothing else than aqueous vapors traversed by the discharges, and which are in general luminous only at a certain height from the ground, either because the air is there more rarefied, or because they are themselves congealed, and more capable, consequently, of liberating their electric light. Then it is, that, from being nearer to the spot where the phenomenon is taking place, the observer hears the crepitation, or whizzing, of which we have spoken, especially if he be in an open country and in a quiet place. But if the arc do not attain to his zenith, he is situated beyond the region in which the meeting of the electric currents takes place; he sees only an arc a little more elevated to the north or the south, according as he is situated in one hemisphere or the other; and he hears no noise, on account of his too great distance. The crepitation is the result of the action of a powerful magnetic pole upon luminous electric jets in its immediate neighborhood. With regard to the sulphurous odor which some observers have perceived, it arises, as does that which accompanies the fall of lightning, from the conversion into ozone of the oxygen of the air, by the passage of electric discharges.
Gisler says, that on the high mountains of Sweden the traveller is sometimes suddenly enveloped in a very transparent fog, of a whitish-gray color inclining a little to green, which rises from the ground, and is transformed into an aurora borealis. The cirro-cumulus and the hazes become luminous when they are traversed by sufficiently energetic discharges of electricity, and when the light of day is no longer present to overcome their more feeble light. Dr. Usher describes an aurora borealis seen in the open day, at noon, May 24, 1778.
MM. Cornulier and Verdier are convinced, after carefully studying the subject, that there are almost always aurorae boreales in the high polar latitudes, and that their brilliancy alone is variable. This conviction is in accordance with the very careful observations which have now been made for four years in the northern hemisphere. It appears, as the result of these, that the aurora borealis is visible almost every clear night, but it does not show itself at all the stations at the same time. From October to March there is scarcely a night in which it may not be seen; but it is in February that it is most brilliant. In 1850 it was observed two hundred and sixty-one nights, and during 1851 two hundred and seven. The proportion of nights in which the aurora is seen is much greater the nearer we are to the magnetic pole.
De la Rive, from whose admirable treatise upon Electricity we have borrowed our general views, and whose theory we have attempted to illustrate in this paper, concludes that the aurora borealis is a phenomenon which has its seat in the atmosphere, and consists in the production of a luminous ring of greater or less diameter, having for its centre the magnetic pole. Experiment shows, as we have seen, that, on bringing about in rarefied air the reunion of the two electricities, near the pole of a powerful artificial magnet, a small luminous ring is produced, similar to that which constitutes the aurora borealis, and animated by a similar movement of rotation. The aurora borealis would be due, consequently, to electric discharges taking place in the polar regions between the positive electricity of the atmosphere and the negative electricity of the earth. These electric discharges taking place constantly, but with intensities varying according to the state of the atmosphere, the aurora borealis should be a daily phenomenon, more or less intense, consequently visible at greater or less distances, but only when the nights are clear,—which is perfectly in accordance with observation.
The aurora australis presents precisely the same phenomena as the aurora borealis, and is explained, consequently, in the same manner.
THE PROFESSOR AT THE BREAKFAST-TABLE
WHAT HE SAID, WHAT HE HEARD, AND WHAT HE SAW
A young fellow, born of good stock, in one of the more thoroughly civilized portions of these United States of America, bred in good principles, inheriting a social position which makes him at his ease everywhere, means sufficient to educate him thoroughly without taking away the stimulus for vigorous exertion, and with a good opening in some honorable path of labor, is the finest sight our private satellite has had the opportunity of inspecting on the planet to which she belongs. In some respects it was better to be a young Greek. If we may trust the old marbles,—my friend with his arm stretched over my head, above there, (in plaster of Paris,) or the discobolus, whom one may see at the principal sculpture gallery of this metropolis,—those Greek young men were of supreme beauty. Their close curls, their elegantly set heads, column-like necks, straight noses, short, curled lips, firm chins, deep chests, light flanks, large muscles, small joints, were finer than anything we ever see. It may well be questioned whether the human shape will ever present itself again in a race of such perfect symmetry. But the life of the youthful Greek was local, not planetary, like that of the young American. He had a string of legends, in place of our Gospels. He had no printed books, no newspaper, no steam caravans, no forks, no soap, none of the thousand cheap conveniences which have become matters of necessity to our modern civilization. Above all things, if he aspired to know as well as to enjoy, he found knowledge not diffused everywhere about him, so that a day's labor would buy him more wisdom than a year could master, but held in private hands, hoarded in precious manuscripts, to be sought for only as gold is sought in narrow fissures and in the bed of brawling streams. Never, since man came into this atmosphere of oxygen and azote, was there anything like the condition of the young American of the nineteenth century. Having in possession or in prospect the best part of half a world, with all its climates and soils to choose from; equipped with wings of fire and smoke that fly with him day and night, so that he counts his journey not in miles, but in degrees, and sees the seasons change as the wild fowl sees them in his annual flights; with huge leviathans always ready to take him on their broad backs and push behind them with their pectoral or caudal fins the waters that seam the continent or separate the hemispheres; heir of all old civilizations, founder of that new one which, if all the prophecies of the human heart are not lies, is to be the noblest, as it is the last; isolated in space from the races that are governed by dynasties whose divine right grows out of human wrong, yet knit into the most absolute solidarity with mankind of all times and places by the one great thought he inherits as his national birthright; free to form and express his opinions on almost every subject, and assured that he will soon acquire the last franchise which men withhold from man,—that of stating the laws of his spiritual being and the beliefs he accepts without hindrance except from clearer views of truth,—he seems to want nothing for a large, wholesome, noble, beneficent life. In fact, the chief danger is that he will think the whole planet is made for him, and forget that there are some possibilities left in the débris of the old-world civilization which deserve a certain respectful consideration at his hands.
The combing and clipping of this shaggy wild continent are in some measure done for him by those who have gone before. Society has subdivided itself enough to have a place for every form of talent. Thus, if a man show the least sign of ability as a sculptor or a painter, for instance, he finds the means of education and a demand for his services. Even a man who knows nothing but science will be provided for, if he does not think it necessary to hang about his birthplace all his days,—which is a most un-American weakness. The apron-strings of an American mother are made of India-rubber. Her boy belongs where he is wanted; and that young Marylander of ours spoke for all our young men, when he said that his home was wherever the stars and stripes blew over his head.
And that leads me to say a few words of this young gentleman, who made that audacious movement lately which I chronicled in my last record,—jumping over the seats of I don't know how many boarders to put himself in the place which the Little Gentleman's absence had left vacant at the side of Iris. When a young man is found habitually at the side of any one given young lady,—when he lingers where she stays, and hastens when she leaves,—when his eyes follow her as she moves, and rest upon her when she is still,—when he begins to grow a little timid, he who was so bold, and a little pensive, he who was so gay, whenever accident finds them alone,—when he thinks very often of the given young lady, and names her very seldom,–
What do you say about it, my charming young expert in that sweet science in which, perhaps, a long experience is not the first of qualifications?
–—But we don't know anything about this young man, except that he is good-looking, and somewhat high-spirited, and strong-limbed, and has a generous style of nature,—all very promising, but by no means proving that he is a proper lover for Iris, whose heart we turned inside out when we opened that sealed book of hers.
Ah, my dear young friend! When your mamma—then, if you will believe it, a very slight young lady, with very pretty hair and figure—came and told her mamma that your papa had—had—asked–No, no, no! she couldn't say it; but her mother—oh, the depth of maternal sagacity!—guessed it all without another word!—When your mother, I say, came and told her mother she was engaged, and your grandmother told your grandfather, how much did they know of the intimate nature of the young gentleman to whom she had pledged her existence? I will not be so hard as to ask how much your respected mamma knew at that time of the intimate nature of your respected papa, though, if we should compare a young girl's man-as-she-thinks-him with a forty-summered matron's man-as-she-finds-him, I have my doubts as to whether the second would be a fac-simile of the first in most cases.
The idea that in this world each young person is to wait until he or she finds that precise counterpart who alone of all creation was meant for him or her, and then fall instantly in love with it, is pretty enough, only it is not Nature's way. It is not at all essential that all pairs of human beings should be, as we sometimes say of particular couples, "born for each other." Sometimes a man or a woman is made a great deal better and happier in the end for having had to conquer the faults of the one beloved, and make the fitness not found at first, by gradual assimilation. There is a class of good women who have no right to marry perfectly good men, because they have the power of saving those who would go to ruin but for the guiding providence of a good wife. I have known many such cases. It is the most momentous question a woman is ever called upon to decide, whether the faults of the man she loves are beyond remedy and will drag her down, or whether she is competent to be his earthly redeemer and lift him to her own level.
A person of genius should marry a person of character. Genius does not herd with genius. The musk-deer and the civet-cat are never found in company. They don't care for strange scents,—they like plain animals better than perfumed ones. Nay, if you will have the kindness to notice, Nature has not gifted my lady musk-deer with the personal peculiarity by which her lord is so widely known.
Now when genius allies itself with character, the world is very apt to think character has the best of the bargain. A brilliant woman marries a plain, manly fellow, with a simple intellectual mechanism; we have all seen such cases. The world often stares a good deal and wonders. She should have taken that other, with a far more complex mental machinery. She might have had a watch with the philosophical compensation-balance, with the metaphysical index which can split a second into tenths, with the musical chime which can turn every quarter of an hour into melody. She has chosen a plain one, that keeps good time, and that is all.
Let her alone! She knows what she is about. Genius has an infinitely deeper reverence for character than character can have for genius. To be sure, genius gets the world's praise, because its work is a tangible product, to be bought, or had for nothing. It bribes the common voice to praise it by presents of speeches, poems, statues, pictures, or whatever it can please with. Character evolves its best products for home consumption; but, mind you, it takes a deal more to feed a family for thirty years than to make a holiday feast for our neighbors once or twice in our lives. You talk of the fire of genius. Many a blessed woman, who dies unsung and unremembered, has given out more of the real vital heat that keeps the life in human souls, without a spark flitting through her humble chimney to tell the world about it, than would set a dozen theories smoking, or a hundred odes simmering, in the brains of so many men of genius. It is in latent caloric, if I may borrow a philosophical expression, that many of the noblest hearts give out the life that warms them. Cornelia's lips grow white, and her pulse hardly warms her thin fingers,—but she has melted all the ice out of the hearts of those young Gracchi, and her lost heat is in the blood of her youthful heroes.