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of his fancy, which he has to shape into realities by the use of certain traits and peculiarities of humanity with which his extraordinary observation has supplied him. Major Pendennis, and Costigan, and Becky Sharp are realities whom Thackeray idealizes, makes characters of fiction out of. But Sam Weller and Mrs. Gamp are the children of fancy whom Dickens makes real, partly by the addition of sundry human attributes, but even more so by the marvellous skill and distinctness with which he brings them and keeps them before us. But in order to do this he is obliged never to lose sight, or to suffer us to lose sight, of those peculiarities, whether of speech, or manner, or condition, which make them for us the realities that

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they are. And in so doing it cannot but happen that he seems to thrust those peculiarities at times somewhat too persistently upon us. In "David Copperfield" this is not so, or much less so than anywhere else, except, of course, in The Tale of Two Cities,' Dickens's only essay at the romance proper, where the characters are subordinate to the story. We may see this, for example, by comparing Omer, the undertaker, in" David Copperfield," with Mould, the undertaker, in "Martin Chuzzlewit." Mould and all his family live in a perpetual atmosphere of funerals; his children are represented as solacing their young existences by playing at buryin's down in the shop, and followin' the order-book to its long home in the iron safe;" and Mr. Mould's own idea of fellowship is of a person one would almost feel disposed to bury for nothing, and do it neatly, too!'' On his first introduction, after old Anthony's death, he sets the seal on his personality by the remark that Jonas's liberal orders for the funeral prove what was so forcibly observed by the lamented theatrical poet-buried at Stratford-that there is good in everything."* That touch is very comical, but also very grotesque; it is a touch of fancy, not of nature. But when David Copperfield, as a man, recalls himself to the recollection of the good-hearted Omer, who had known him as a boy, the undertaker is revealed

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"Martin Chuzzlewit," chap. xix. NEW SERIES.-VOL. XXXVII., No. 2

in a very different fashion. To be sure," said Mr. Omer, touching my waistcoat with his forefinger; and there was a little child too! There was two parties. The little party was laid along with the other party. Over at Blunderstone it was, of course. Dear me! And how have you been since ?'’* Every one must be conscious of the difference here.

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Coragio and think of 2850," wrote Macaulay in his diary, to console himself for some bitter pill of American criticism he had been forced to swallow. We need not cast our thoughts quite so far into the future to see that much of what gave Dickens his popularity, and still keeps it with so many of us, will avail him nothing then.. Those qualities which so endeared his writings to the great mass of his contemporaries, and won the respect even of those who could not always admire the method and direction of their employment, will have for posterity no more attraction than will many of the subjects on which he so lavishly and dauntlessly expended them. Our descendants will have, we may be very sure, too frequent and too real claims upon their compassion to let them spare many tears for those rather theatrical personages which Dickens too often employed to point his moral. Harsh as it may seem to say, whatever his writings may actually have done to reduce the sum of human suffering will tell against rather than for them. It will always be so with those who employ fiction for the purpose of some particular social or political reformation; for the wrongs they help to remove, and the evils they help to redress, will seem slight and unreal in the pages of fiction, because they have so long ceased to form a part of actual existence. soul of good-nature and kindness is a quality we are right to recognize in contemporary work, and for that work it constitutes a special and a noble title to our praise; but posterity will judge the writings of one whom their forefathers called a great writer by the sheer value of the writing, and such praise, if it be found to rest on no more practical foundation, will seem to them, to use the words of one of Dickens's own

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* "David Copperfield," chap. xxi.

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characters, pious, but not to the purpose. It is inevitable that much of his serious and sentimental work will have for future generations neither the attraction nor the solidity that it had for his own. For the tears he sought to draw, the graver feelings he sought to move, he went too often, if I may use the word, to local sources, too often to artificial. What Lamb said of comedy is surely true to a certain extent of all fiction our fire-side concerns, attractive as they are to us, cannot in reason have the same attraction for those who have never warmed themselves at our hearth. Each age has its own fireside; each age provides its own tears. The familiar matter of to-day will not be the familiar matter of tomorrow. It is the splendid sorrows of a Priam or a Lear that touch the heart of Time.

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"The cease of majesty Dies not alone; but like a gulf doth draw What's near it with it; it is a massy wheel, Fix'd on the summit of the highest mount To whose huge spokes ten thousand lesser things

Are mortised and adjoin'd: which when it falls

Each small annexment, petty consequence, Attends the boisterous ruin. Never alone Did the king sigh, but with a general groan."

But the quality of a humor founded in the roots of our common humanity can never wax old nor die, and it seems im

possible to imagine a day when the world will refuse to laugh with Dickens. The careless glance of curiosity, or the student's all-ranging eye, may turn a century hence upon the little Nells and Pauls, the Joes and the Trotty Vecks; but the Wellers and the Pecksniffs, the Swivellers and the Micawbers must surely abide forever, unchanging and immortal-immortals of lesser note, and with more of mortal mixture, but still of the same lineage with Falstaff. And then with the laughter that they stir will be remembered and confessed the real worth of the noble praise Dean Stanley gave to their creator's memory, praise whose significance our own age has in truth too ample means for judging: "Remember, if there be any who think you cannot be witty without being wicked; who think that in order to amuse the world, and to awaken the interest of hearers or readers, you must descend to filthy jests, and unclean suggestions, and debasing scenes, so wrote not the genial loving humorist we now mourn. However deep his imagination led him to descend into the dregs of society, he still breathed an untainted atmosphere around him; he was still able to show by his own example that, even in dealing with the darkest scenes and most degraded characters, genius could be clean and mirth decent."Fortnightly Review.

STAR UNTO STAR.

BY RICHARD A. PROCTOR.

WHEN, nearly twenty years ago, Drs. Huggins and Miller published the first results obtained from the spectroscopic study of stars, few could have supposed that a line of research so difficult and delicate would lead to the bold and startling views of the star depths which now seem opening out before us. Still less would it have been thought that the method of research would be so modified that the observations belonging to it could be pursued without the direct personal study of the stellar spectra which had been found so difficult and even (where exact researches were in question) so painful. In 1864 the observer who wished to determine whether

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a special substance existed in the vaporous atmosphere of a star, had to compare the spectrum of the star directly with the spectrum of the substance. other words, he had first to turn his telescope upon the star with such precision that the image of the star should fall on the fine slit of the spectroscope (and be kept there by clock motion, driving the telescope throughout the operation), and the light of the star being then sifted out by the action of the prisms in the spectroscope, so as to form a rainbow-tinted streak or spectrum crossed by dark lines where certain tints are missing (on account of special absorptive action in the vaporous atmos

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phere of the star), the observer had to bring into the same field of view, and into precisely corresponding position, by the action of the same spectroscope, $2 the bright line spectrum of whatever substance he wished to deal with. If the bright lines forming the spectrum of magnesium, or sodium, or calcium, or the like, were found to correspond exactly with dark lines or missing tints in the spectrum of the star, then the observer would know that the particular substance giving those bright lines (or more correctly shining with those tints) existed in the atmosphere of the star. But he might very well be in doubt as to the precise accuracy of the coincidences (on which everything depends), or he might not be able to perceive clearly, yet might suspect the existence of one or other of the dark lines necessary to complete the evidence. To make sure he must cause the electric spark producing the spectrum of the substance he is dealing with to flash again and again out of the darkness, wearying the eye by the constant alternation of darkness with bright light. Not a few minutes, but many hours, or even several observing nights, would be required for each observation of the sort; and later, some other observer, with different visual powers, or with instruments of greater or less precision, might throw doubt on the accuracy of the observation, and the whole work might have to be repeated.

Now, all this is changed. A photographic record of the spectrum is taken (hitherto only of the blue, violet, and ultra-violet part, but before long the whole visible spectrum, and parts invisible beyond the red and violet, will doubtless be photographed), and, either at the same time or under precisely the same optical conditions, a photograph of the sun's spectrum (not taken directly from the sun, but either from the twilight sky or from a planet like Venus which reflects pure sunlight): and then the known dark lines in the solar spectrum can be compared directly with the dark lines in the spectrum of the star. If doubt be afterward thrown on the result, the slips with the recorded photographic spectra are always available for comparison. And thus star after star can be added to the list of those whose light-record of their vaporous

structure has been obtained. Fainter and fainter stars can be dealt with as the sensitive plates are made more delicate, or as the accuracy of the clockdriving of telescopes is increased, until the photographic plate may be exposed during the whole of any clear night to receive the light impressions from a star. Already Dr. Draper has obtained records of the spectra of stars of the tenth magnitude--that is, far beyond the range of ordinary vision-though as yet such records of faint stars have not been available for the kind of research we are considering. In fact, they have only been received accidentally, so to speak, when search was being made for something entirely different.

We are not, however, here concerned to consider at any length the methods employed. It is interesting, and will appear more so as we proceed, to note how widely the research we are considering is likely to be extended in the future. But at present we propose chiefly to discuss the most remarkable result which has rewarded the method of spectroscopic inquiry into the stars, whether by ordinary vision or by the use of photographic appliances.

The result to which we refer is the marshalling of the stars into orders, different in color, which spectroscopic analysis shows to be due to difference in present physical constitution, which again analogical reasoning shows to be due to difference in age.

Take first the bluish-white stars of which Sirius, Vega, Altair, and others are typical.

In the first place, we note that the only star of this order whose distance has been even roughly determined (Alpha Centauri in the southern hemisphere is a yellowish-white star) is demonstrably a much larger orb than our own sun, if the quantity of light which a sun emits is any indication of size. Sirius is so remote that the motion of the earth in her vast orbit, 185 million miles in diameter, scarcely at all affects the apparent position of that brilliant star. Very exact and careful study of the star indicates apparent motion (due to the earth's real motion) in a tiny ellipse, the larger axis of which is roughly about the 4000th part of the moon's apparent diameter-the nature of the observation being such that this

larger axis may be as much as the 3000th or as little as the 5000th part of the moon's apparent diameter, or even lie outside those limits. Taking the mean of the best measurements, a distance is inferred so great that our sun's light, were he placed at that distance, would be reduced to about the 50th part of the apparent lustre of a leading firstmagnitude star, or, roughly, to about the 200th part of the lustre of Sirius. Hence it would follow that if an average square mile of the surface of Sirius emits as much light as an average square mile of the sun's surface, the surface of Sirius must be 200 times as large as the surface of our sun. If so, the diameter of Sirius would be about 14 times the diameter of the sun (for 14 times 14 are 196), and his volume about 2800 times, or in round numbers 3000 times the volume of the sun. We can hardly suppose that this volume, or probably his mass, is less than a thousand times larger than the sun's.

Of other stars of the bluish-white order we know less, with precision, but we do know so much as this, that all the brighter ones must be, and therefore even the fainter ones probably are, very much larger than the sun. For though the actual distance of Vega and Altair, for example, cannot be determined, it is because they are so far away that attempts at measurement fail. If either of them were as near as Sirius, its distance would be as readily determinable. But the measures which, applied to Sirius, give a recognizable result, fail utterly when applied to Vega and Altair. It is true, results are published in our books of astronomy which if accepted would indicate a measured distance in the case of Vega, but it is utterly untrustworthy. Vega and Altair lie beyond the range of the best methods of measurement yet invented. But noting that their lustre still exceeds many times that which the sun would have if removed to the distance of Sirius, we infer safely that the lustre of these two bluish-white stars exceeds in yet greater degree that which our sun would have if removed to their distance in what precise degree we cannot determine, but we may confidently say that these stars are very much larger than our own sun. The same argument applies to all the brighter stars of

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the bluish-white kind. thus inferred that so many stars of this color exceed our sun in size, it is a highly probable inference that all do (the fainter being simply very much farther away), if it shall appear that all the stars of this kind possess certain physical characteristics which stars of other colors do not possess. For it is a fair inference that because all bluish-white stars yet examined possess such characteristics, so will others of the same color which may hereafter be examined; and again, that because no other stars have yet been found to possess these characteristics but stars of a bluish-white color, therefore others which may hereafter be found to possess them will also be of this color; it is clearly as fair an inference to assume that the great size characterizing all the stars of this kind yet tested or testable in this respect is a characteristic also of the class.

Now it appears from direct spectroscopic study of these stars, as well as from their spectra, that they differ in physical structure in marked manner and degree from our sun. The lines which indicate the presence of relatively cool hydrogen-hydrogen exerting an absorptive action on the light from the central glowing mass-in these stars, are always much stronger and broader than in the spectrum of our sun. I do not dwell here on a question which has arisen as to a certain line which appears to be common both to calcium and hydrogen, and has therefore given rise to certain discussions (running, in my opinion, far in advance of the evidence) as to the identity of some element common to both calcium and hydrogen, which of course, according to that view, would neither of them be elements. I prefer now to consider only the broad lines of distinction between the various orders of stars, and not to discuss minutia which may hereafter very probably be shown to be altogether without significance.*

Now the great breadth and strength

*Just as Professor Young, by using spectroscopes of great dispersive power and showing lines to be diverse which with inferior instruments had seemed identical, has entirely destroyed the imagined validity of evidence on which certain very bold assumptions as to the elementary constitution of matter had been based.

of the hydrogen lines in these monstrous suns (suns exceeding our sun much as our sun exceeds Jupiter and Saturn, and as these planets exceed our earth, Venus, and Mars) may be taken safely enough to indicate the existence of much deeper and denser atmospheres of relatively cool hydrogen around those suns than exist around our own. Yet the in tense brightness and whiteness of those suns serve to show that such deep envelopes of relatively cool hydrogen are by no means due to the longer continuance of a process of cooling. On the contrary, it seems clear that it is the greater intensity of the radiation of those parts of the stars' light which form the continuous background of the spectrum, and not the greater intensity of the absorptive action of the hydrogen, which really occasions these lines to appear broad and dark. The hydrogen itself, which, owing to the great lightness of this element under the same conditions of temperature and pressure, extends high above the other gaseous envelopes, forming the outer parts of these intensely bright white stars, is no doubt itself intensely hot. Most probably it is far hotter than those hydrogen layers which cause the finer absorptive lines of hydrogen in the spectrum of our own sun and his fellows. But so much more intense is the light radiated from the glowing mass within (mostly from glowing gas at great pressure, I think) that the absorptive lines of hydrogen appear by contrast very broad and very strong. On this view we may fairly assume that the darkness of the hydrogen lines is a characteristic of stars at a much higher temperature than our sun and suns of his class. And finding this characteristic associated with some stars which are certainly of enormous size, and with other stars which may be thus exceptionally large, we are led to infer that this association is not accidental-that all stars having these very strong hydrogen lines are very much larger than our own sun.

Whether we can accept this inference or not will depend very much on whether we can regard the youth of a sun as in any way correlated with the sun's size. The reasoning which I have applied to planets-the justice of which reasoning seems confirmed by

the accordance of the results to which it leads with observed facts-may be applied also to the stars. I have shown that if two planets of different size are at any given epoch in the same stage of planetary life—that is, at the same temperature the smaller will presently pass into a more advanced stage than the larger will have attained to, because it will part with its heat at a relatively greater rate. Supposing, for instance, the diameter of the larger planet is twice as great as that of the smaller, and therefore the surface four times as great, and the volume (or mass, if the planets are of nearly the same density) eight times as great as that of the other, it is evident that as the quantity of heat is proportional to the quantity of matter, or eight times as great in the larger planet when the two are at the same temperature, while the rate of emission, being proportional to the surface, is but four times as great, the supply of heat in the larger will last twice as long as the smaller supply af heat in the smaller planet. Now, as I have said, this reasoning applies equally to the stars; and if we could only be assured that at any given time two stars of unequal size were in exactly the same stage of stellar life, we should be sure that at any much later stage the smaller star would be much more advanced in stellar life than the larger.

The difficulty arises here, however, that we have no means of proving, but on the contrary strong reason for doubting, whether the stars of our galaxy began their existence of stars at any common time. When we see the various orders of nebulous masses within the galaxy, and note how very different these nebulæ seem to be as to condition, while the very existence of true nebulæ (many of which we may regard as unformed suns or star clusters) indicates the great diversities of age existing among the occupants of stellar space, we perceive how very unsafe it would be to assume that the stars, simply because they are stars, began their existence as such all at the same or nearly the same time. The contrary is not only far more probable, but to all intents and purposes certain.

All we can safely assume is, that the greater size and mass of a star indicates

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