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moving in all directions, but the prism, | Happily the days are not yet over when which can take note only of motions which discoveries can be made without an armory are precisely in the line of sight, gives us of instruments. direct information of that component only of a star's motion which is towards or from us. The method is applicable not only to the drift of star-systems, but also to the internal motions within those sys
It is obvious that a star moving round in an orbit, unless the plane of the orbit is across the line of sight, has alternate periods of approach and recession. A line in its spectrum will be seen to swing backwards and forwards relatively to a terrestrial line of the same substance in times corresponding to the star's orbital period. It is equally clear that if in a binary system both stars are bright, the spectrum will be a compound one, the spectrum of one star superposed upon that of the other. If the spectra are identical, all the lines will be really double, but apparently single when the stars have no relative motion; and will separate and close up as the stars go round.
It was by this method, from the motions of the variable star Algol, photographed at Potsdam, that the dusky companion which periodically eclipses its light in part, stood revealed; and a similar discovery was made there of the companion of Spica. Of these double stars only one companion was bright, but by the opening and closing of double lines in the spectrum of Mizar, Professor Pickering brought to light a pair of gigantic blazing suns equal together to forty times the sun's mass, and whirling round their common centre of gravity with the speed of some fifty miles a second. Then followed, also at the Harvard observatory, the discovery in 6 Auriga, of an order of close binary stars hitherto unknown. The pair revolve with a speed of seventy miles a second within some seven and a half millions of miles of each other.
Now it was by this method of spectroscopic observation that the remarkable state of things existing in the new star was revealed to us. It is not a little surprising that a new star, as bright as the fifth magnitude, could burst out almost directly overhead in the heavens, and yet remain undiscovered for nearly seven weeks. Europe and the United States bristle every clear night with telescopes from open observatories, which are served by an army of astronomers; yet the discovery of the new star was left to an amateur, Mr. Anderson, possessed only of a small pocket-telescope and a star-chart.
As soon as the news reached Cambridge, U.S., Professor Pickering, by means of photographs which had been taken there, was able to cause the part of the sky where the new star appeared to pass again under examination, as it had appeared at successive intervals during the last six years, but with the result that the new star's place had remained unoccupied all that time by any star so bright as the eleventh magnitude. For about a year a closer watch has been kept upon the sky at Cambridge by means of a photographic transit instrument driven by clockwork, which automatically patrols the sky every clear night, and registers all stars as bright as the sixth magnitude in a great zone sixty degrees in breadth, and three hours of right ascension in length. On December 1st the nova was not recorded, but the next clear night, December 10, it was already of the fifth magnitude. Max Wolf photographed this part of Auriga on December 8, including all stars to the ninth magnitude, but the nova was not on the plate. The star therefore must have sprung up from below the ninth magnitude to the fifth within two days at the longest.
On Professor Pickering's plates taken in December, the nova appears without any surrounding nebulosity. This point, which has been in dispute, appears to be settled by a plate taken with an exposure of three hours by Mr. Roberts, which fails to show any appearance of a surrounding nebula, though a similar accumulation of the light-action of the Pleiades fills the whole background with nebulæ.
The nova was discovered at the end of January by Mr. Anderson, and from February I was observed at many observatories. Its magnitude then was about the fourth and one-half magnitude. Though its light showed continual fluctuations, a slow but steady decline set in, carrying it down to about the sixth magnitude in the early days of March; but after March 7, these swayings to and fro of its light, set up doubtless by the commotions attendant on the cause of its outburst, calmed down, and the star fell rapidly and with great regularity to about the eleventh magnitude on March 24, and by the beginning of
Professor Pickering informs the writer that the new star was still visible at Harvard Observatory on April 26. Its magnitude was then scarcely lower than at the beginning of the month, on the scale of their meridian photometer, 14'5.
April to the fifteenth magnitude. So short | come in before each other, the cooler gas was the star's day of glory.
We commenced our observations of its spectrum on February 2. The spectrum showed a brilliant array of bright lines, conspicuous among which were the wellknown lines of hydrogen, and three lines in the green. A remarkable phenomenon was seen; each bright line seemed to cast a shadow, for on the blue side of each was narrow space of intense blackness. When the light from a hydrogen vacuum tube was thrown into the spectroscope, the hydrogen line at F did not fall upon the middle of the bright stellar line, but towards the blue edge. The secret was revealed; we had a magnificent example, on a great scale, of motions in the line of sight. Two mighty masses of hydrogen fleeing from each other, the hotter one which emitted the bright lines going from us, while the cooler one, producing the dark shadows by absorption, approached us, with a relative velocity as great as five hundred and fifty miles a second.
It would be out of place here to describe the spectrum in any detail; it may suffice to say that we were sure that the spectrum of the star showed no relationship to that of the bright-lined nebulæ, nor to the usual hydro-carbon spectrum of comets. Its general features suggested rather a state of things similar to the erupted solar surface. This view was confirmed by a photograph of its spectrum which we took with a mirror of speculum metal and a spectroscope with a prism of Iceland spar and lenses of quartz, so that the extreme violet part of the star's light was not cut off by passing through glass. The fainter continuous spectrum and the brilliant lines were found to extend upon the plate nearly as far as does the light of Sirius, and not far short of the place where our atmosphere stops all celestial light. The whole range of the hydrogen lines, including the ultra-violet series present in the white stars and H and K, were bright as they show themselves occasionally reversed in photographs of the solar prominences, and each accompanied by a line of absorption.
A remarkable feature of great significance in the character of the hydrogen lines, bright and dark, must be noticed. They appeared to be sometimes double and sometimes triple- the dark ones as if by fine bright threads superposed upon themand, indeed, to be subject to continual change. Now when on the sun's surface, or in the laboratory, portions of the same gas at different temperatures
may cause a narrow absorption line to form upon a broader bright line, and thus impart to it the appearance of a double line; or in the case of hotter gas, a narrow bright line upon a dark line. Professors Liveing and Dewar, whose researches with the electric arc-crucible have made them specially familiar with the ever-changing guises and disguises of this Protean phenomenon of reversal, as it is called, have recorded cases not only of double reversals giving apparent triplicity to a single line, but even of threefold reversals. The unsymmetrical division of bright and dark lines, which was occasionally seen in the spectrum of the nova, frequently presents itself in the laboratory, in consequence of the unequal expansion on the two sides of the line on which the reversed line falls. Unless we accept this obvious interpretation of the multiple character of the stellar lines, we should have to assume a system of at least six bodies all moving with different velocities.
It is important to state that the waning of the star appeared to produce no material alteration of its spectrum, but only such apparent changes as necessarily come in when parts of an object differ greatly in brightness. On March 24th, when the star's light had fallen so low as to about the eleventh magnitude, we could still glimpse the faint continuous spectrum, upon which the remarkable quartet of bright lines still shone out without any change of relative intensity. Professor Pickering informs me that in his photographs the principal lines in that part of the spectrum "faded in the order, K, H, a, F, h, and G, the latter becoming brighter as star was faint." Omitting the calcium lines H and K, which varied, the order of disappearance agrees with that of the sensitiveness of the plate for these parts of the spectrum, and supports the view that the star's spectrum remained without material change through this great range of magnitude.
How are we to account for the appearance and doings of this new star, or rather stars? For, as we have seen, the great shifts of the bright and dark lines, the bright to the red, the dark to the blue, clearly indicate two bodies having a relative motion in the line of sight of about five hundred and fifty miles a second. Now, during the whole time, some seven weeks, that the spectrum was under observation, this relative velocity was main tained materially unaltered, though small changes beyond the reach of our instru
interior of the bodies to give rise to enormous eruptions of the hotter matter from within, immensely greater but similar in kind to solar eruptions.
In such a state of things we should have, in the existence of portions of the same gas at different levels and temperatures, conditions so favorable for the production of reversed lines undergoing continual change, similar to those exhib ited by the lines of the nova, that we could not suppose them to be absent. The integration of light from all parts of the disturbed surfaces of the bodies might give breadth to the lines, and might ac count for the varying irregularities of intensity of different parts of the lines.
The source of the light of the continuous spectrum, upon which were seen the dark lines of absorption shifted towards the blue, must have remained behind the cooler absorbing gas; indeed must have formed with it the body which was ap
ments may have taken place. A reasonable explanation may perhaps be found, if we venture to assume, though with some hesitation, as the subject is very obscure, two gaseous bodies, or bodies with gaseous atmospheres, moving away from each other after a near approach in parabolic or hyperbolic orbits. If our sun were nearly in the line of axis of the orbits, the components of the motions of the two bodies in the line of sight after the bodies had swung round, might well be as rapid and remain relatively as unchanged as those observed in the new star. Unfortunately, decisive information from the motions of the two bodies at the critical time of the outburst is wanting, for the event through which the star became bright had been over for some forty days before observations were made with the spectroscope. Analogy from the variable stars of long period would suggest the view that the near approach of the two bodies may have been of the nature of a periodical disturb-proaching us, unless we assume that ance arising at long intervals in a complex system of bodies. Chandler has recently shown in the case of Algol that the minor irregularities in the variation of its light are probably caused by the presence of one or more bodies in the system besides the bright star and the dusky one which partially eclipses it. To a similar cause are probably due the minor irregularities which form so prominent a feature in the waxing and waning of the variable stars as a class. We know, too, that the stellar orbits are usually very eccentric. In the case of y Virginis, the eccentricity is as great as o'9, and Auwers has recently found Sirius to have the considerable eccentricity of 0.63.
But a casual near approach of two bodies of great size would be a greatly less improbable event than an actual collision. The phenomena of the new star scarcely permit us to suppose even a partial collision, though if the bodies were diffused enough, or the approach close enough, there may have been possibly some mutual interpenetration and mingling of the rare gases near their boundaries.
An explanation which would better accord with what we know of the behavior of the nova may, perhaps, be found in a view put forward many years ago by Klinkerfues and recently developed by Wilsing, that under such circumstances of near approach enormous tidal disturb ances would be set up, amounting, it may be, to partial deformation in the case of a gaseous body, and producing sufficiently great changes of pressure in the
both bodies were moving exactly in the line of sight, or that the absorbing gas was of very enormous extent.
The difference of state between the two bodies, as shown by the receding one emitting bright lines, while the approaching body behaved similarly to a white star in giving a continuous spectrum with broad absorption lines, may perhaps be accounted for by the two bodies being in different evolutionary stages, and differing consequently in diffuseness and in temperature. We appear, indeed, to have a similar state of things in the variable star ẞ Lyræ, of which one component star gives bright lines, and the other a spectrum with dark lines of absorption. In the case of the nova, we must assume a similar chemical nature for both bodies, and that they existed under conditions sufficiently similar for equivalent dark and bright lines to appear in their respective spectra.
We know nothing of the distance of the nova from our system, but the assumption is not an improbable one, that it was as far away from us as the nova of 1876, for which Sir Robert Ball failed to find any parallax. If this be so, the emission of light suddenly set up in the very faint stars, certainly within two days, and possibly, as in the case of the nova of 1866, within a few hours, was much greater than the light emitted by our sun. Yet within some fifty days after its discovery at the end of January, its light fell to about the one-three-hundredth part, and in some three months to the one-ten-thousandth part. So long as its spectrum could be
grave, against the wall. And so enough of it; and may the poor little Package arrive safe, and kindly bring me before you again!
observed, the chief features remained un- | fact, covering the dust of the Poet; the changed. Under what conditions could Figure itself standing at the head of the we suppose the sun to cool down sufficiently for its light to decrease to a similar extent in so short a time, and without the incurring of material changes in the solar spectrum? It is, therefore, scarcely conceivable that we have to do with the conversion of gravitational energy into light and heat. On the view we have ventured to suggest, the rapid calming down, after some swayings to and fro of the tidal disturbances, and the closing in again of the outer and cooler gases, together with the want of transparency which often comes in under such circumstances, might acing in the dark chaos that it could seem count reasonably for the very rapid, and at first curiously fluctuating, waning of the nova, as well as for the want of change in its spectrum.
The writer may be permitted to state that the view suggested by Dr. Allen Miller and himself in the case of the nova of 1866, was so far similar that they ascribed its outbursts to erupted gases, but with our present knowledge of the light-changes of stars, the writer would now hesitate to make the further sug. gestion that chemical action may have contributed to its sudden and transient splendor. WILLIAM HUGGINS.
From The New Review.
I have been silent this long while, only hearing of you from third parties; the more is the pity for me. In fact, I have not been well; travelling, too, in Scotland, in Ireland; much tumbled about by manifold confusions outward and inward; and have, on the whole, been silent to all the world; silent till clearer days should come. I have still no fixed work; noth
beautiful to conquer and do; - no work to write at; and as for reading, alas that has become, and is ever more becoming, a most sorry business for me; and often enough I feel as if Caliph Omar, long ago, was pretty much in the right after all; as if there might be worse feats than burning whole continents of rhetorical, logical, historical, philosophical jangle, and insincere obsolete rubbish, out of one's way; and leaving some living God's-message, real Koran or "Thing worth reading" in its stead! These are my heterodoxies, my paradoxes of which too I try to know the limits. But in very deed I do expect from the region of Silence some salvation for myself and others; not from the region of Speech, of written or Oral Babblement, unless that latter very much alter soon! Cant has filled the whole universe, - from
LETTERS OF CARLYLE TO VARNHAGEN Nadir up to Zenith, God deliver us!
Chelsea, London: Decr. 16, 1846.
MY DEAR SIR, Yesterday there went from Mr. Nutt's shop, imbedded, I suppose, in a soft mass of English Literature, -a small box bearing your address; which I hope may reach you safely, in time for a New-year's remembrance of me. It is a model of the Tomb of Shakespeare, done by an ingenious little artist here; which may perhaps interest you or some of your friends, for a moment. I understand the likeness in all respects to be nearly perfect, - which indeed is the sole merit of such a thing; - a perfect copy of the old monument, as it stands within Stratford Church for these two centuries and more:-only with regard to that part of the Inscription, "Sweet friends, for Jesus' sake," &c. to these lines, which in the model have found room for themselves directly under the Figure of Shakespeare, you are to understand that, in the original, they lay on the floor of the Church, some three feet in advance of the Figure; in
Preuss's "Friedrich" has not yet reached hither, except through private channels; but I mean to make an effort for sight of it by and by. I have the old "Euvres de Frédéric " beside me here; but without chronology and perpetual commentary they are entirely illegible. "Zinzendorf" received long since, and read: thanks! Yours ever truly,
Chelsea, London: March 3, 1847.
MY DEAR SIR, Some ten days ago your new volume of "Denkwürdigkeiten was safely handed in to me; I fancy it must have been delayed among the ice of the Elbe, for the note accompanying it bears date a good while back. Thanks for this new kindness; a valued Gift, to be counted with very many other which I now owe to you. - Some time before, there had arrived your announcement that the little Tomb of Shakespeare had made its way across the impediments and, what was very welcome to me, that you meant
be excited and ever anew excited, till it also had to kindle and flame along with him. "Kerle, Ihr sehet aus wie Schweine !" and then these scenes, as at Katztadt, Napoleon just behind me, say you?" or to the enthusiastic Public on the streets of Halberstadt, " So mögt Ihr denn alle -"- I have laughed aloud at such naivetes, every time they have come into my mind since. Thanks again and again for painting us such pictures, a real possession for all men.
to show it to Herr Tiek. Surely, there is
which nevertheless one must persevere !
Of my own affairs I can report no alteration hitherto. I remain contentedly idle; shall doubtless feel a call to work again by and by, but wait unbeschreiblich ruhig (as Attila Schmelze has it) for that questionable consummation! I am very seri ous in my ever deepening regard for the I have read the new volume of "Denk-"Silences" that are in our Existence, würdigkeiten ;" and am veritably called to quite unheeded in these poor days; and thank you, not in my private capacity do, for myself, regard Book-writing in alone, but as a speaker for the Public such a time as but a Pis-aller. withal. If the Public thought as I do on such matters, that is to say, if the Public were not more or less a blockhead - the Public would say to itself, "This is the kind of thing that before all others is good for me at present! This, to give me an account of memorable actions and events, in more and more compact, intelligent, illuminative form, evolving for me more and more the real essence of said actions and events, this is Literature, Art, Poetry, or what name you like to give it; this is the real problem the writing-man has to solve for me, at present." Truly if I had command over you, I should say, "Memoirs, and ever new Memoirs !" There are no books that give me so lively an impression of modern Facts as these of yours do. Withal I get a view as if into the very heart of Prussia through them; which also is highly valuable to me. I can only bid you persevere, give us what is possible; and must reflect with regret that one man's capabilities in such respect are limited and not unlimited. Last week too I have read with the live-ness for the Sequel too! The book does liest interest your book on "Blücher," which I had not sufficiently studied before. A Capital Book; a capital rough old Prussian Mastiff set forth to us there! I seem to see old Blücher face to face; recognize his supreme and indispensable worth in that vast heterogeneous Combination, which also to him was indispensable; for in a common element, one sees, he might very easily have spent himself, as hundreds like him have done, to comparatively small purpose; but that huge, inert mass was always there to fall back upon, to VOL. LXXIX. 4083
Chelsea, London: Nov. 5, 1847. MY DEAR SIR, — It is a long time since I heard from you; a long time since I wrote to you, a still longer indeed; so that, however I may regret, there is no room for complaining: it is my own blame! Your last letter found me in Yorkshire; wandering about the country, as I long continued to do, in the brightest Autumn weather; I did not get the Schiller book into actual possession till my return home, some little while ago; when I found there had a second volume also arrived. Many kind thanks to you for such a Gift. For its own worth, and for sake of the Giver, it is right welcome to me. I finished the second volume last night; my most interesting book for many months past; in great haste, I send you forthwith a word of hasty acknowledgment:-in great eager.
not say who is Editor; have not You yourself perhaps some hand in it? Whoever the Editor may be, the whole world is bound to thank him. Never before did one see Schiller; the authentic homely Prose Schiller, out of whom the Hero Schiller as seen in Poetry and on the Public Stage hitherto, had to fashion himself and grow! And truly, as you say, they are one and the same. For the veracity, and real unconscious manliness of this poor, hungry Schilier of Prose, fighting his battle with the confusion of