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binary systems; clusters of stars; periodical stars; of varied and accelerating periods of such stars,-all seem to point the other way: leaving, though possibly facts small in amount, the original assumption a mere guess, unsupported by all that three centuries of most diligent, and in other respects, successful research, have been able to bring to light. All the knowledge of times succeeding Copernicus, Galileo, and Kepler, (who might well believe the stars to be in every sense suns); — among other things, the disclosure of the history of our own planet, as one in which such grand changes have been constantly going on; the certainty that in by far the greatest part of the duration of its existence it has been tenanted by creatures entirely different from those which give an interest, and thence a persuasiveness, to the belief of inhabitants in worlds appended to each star; the impossibility of which appears, in the gravest consideration of transferring to other worlds such interests as belong to our race in this world; all these considerations, it would seem, should have prevented that old and arbitrary conjecture from growing up, among a generation professing philosophical caution and scientific discipline, into a settled belief. Finally, it will be time enough to speculate about the inhabitants of the planets which belong to such systems, as soon as we shall have ascertained that there are such planets,—or that there is one such.*
In the Dialogue, written after the first edition of the "Essay" had appeared, the Essayist greatly strengthened the position for which he had contended in it, by an important passage containing the results of the eminent astronomer M. Struve's recent examination of double stars, and the result of his elaborate and comprehensive comparison of the whole body of facts in stellar astronomy. Among the brighter stars, he arrives at the conclusion, that every FOURTH such star is physically double; and that a completed knowledge of double stars may prove every THIRD bright star to be physically double! And in the case of stars of inferior magnitude, Dial., pp. 20-23.
Ch. viii., passim.
that the number of insulated stars, though indeed greater than that of such compound systems, is nevertheless only three times, perhaps only twice as great. Thus the loose evidence of resemblance between our Sun and the fixed stars becomes feebler the more it is examined; and the assumption of stellar planetary systems appears, when closely scrutinised, to dwindle away to nothing.t
Now, to so much of the foregoing facts and speculations as are contained in the Essay, from which we have faithfully and carefully extracted the substance, in order that our readers may judge for themselves, Sir David Brewster answers, in effect, and generally in words, thus :
The greatest and grandest truth in astronomy, is the motion of the solar system, advancing with all the planets and satellites in the heavens, at the rate of fifty-seven miles a second, round some distant invisible body, in an orbit of such inconceivable dimensions, that millions of years may be required for a single orbit. When we consider that this centre must be a sun with attendant planets like our own, revolving in like manner round our sun, [?] or round their common centre of gravity, the mind rejects, almost with indignation, the ignoble sentiment that Man is the only being performing this immeasurable journey
and that Jupiter, Saturn, Uranus, and Neptune, with their bright array of regal train-bearers, are but as colos sal blocks of lifeless clay, encumbering the Earth as a drag, and mocking the creative majesty of Heaven. From the birth of man to the extinction of his race [!] the system to which he belongs will have described but an infinitesimal arc in that grand cosmical orbit in which it is destined to move. This affords a new argument for the plurality of worlds. Since every fixed star must have planets, the fact of our system revolving round a similar system of planets, furnishes a new argument from analogy; for as there is at least one inhabited planet in the one system, there must for the same reason be one in the other, and consequently as many as there are systems in the Universe. ‡ Thus our system
More Worlds than One, Ch. vi., passim.
is not absolutely fixed in space, but is connected with the other systems in the Universe.
The Fixed Stars are suns of other systems, whose planets are invisible from their distance, as are ours from the nearest fixed star. Every single star shining by its own native light is the centre of a planetary system like our own-the lamp that lights, the stove that heats, and the power that guides in their orbits, inhabited worlds Like our own. Many are double, with a system of planets round each, or the centre of gravity of both. No one can believe that two suns would be placed in the heavens, for no other purpose than to revolve round their common centre of gravity. It is "highly probable," that our Sun is one of a binary system, and has at present an unseen partner; and we are "entitled to conclude" that all the other binary systems have at least an inhabited planet: wherever there is a self-luminous fixed or movable Sun there must be a planetary system; and wherever there is a planetary system, there must be life and intelligence.*
in motion; and the further attempt to show the direction of that motion;and again, the hypothesis that the Sun itseif revolves round some distant object in space." These minute inquiries and bold conjectures, he says,
cannot throw any light on the question, whether any part besides the earth be inhabited: any more than the investigation of the movements of the ocean and their laws can prove or disprove the existence of marine plants and animals. They do not, on that account, cease to be important and interesting objects of speculation, but they do not belong to our subject." As to the Sun's motion, we are bound to say, that the Astronomer Royal has recently declared that "every astronomer who has examined the matter carefully, has come to the conclusion of Sir William Herschell, that the whole solar system is moving towards a point in the constellation Hercules." Before quitting this part of the subject, we may state that the Essayist, in his second Preface,¶ points out the insecure character of astronomical calculations as to the amount of absolute light ascribed to some of the fixed stars. It has been estimated that the illuminating power of Alpha Centauri is nearly double that of the Sun, placed at that distance, which is two hundred thousand times as far off as is the Sun; but Sir John Herschell will not concur in more of the calculation than attributes to the star the emission of more light than our Sun. Surely the critical and precarious character of such calculations should not be lost sight of by candid inquirers, but incline them to scan somewhat closely any pretensions tinctured by astronomic dogmatism.
Apart from the assertion of his cardinal principle with which we are familiar, namely, that since our Sun has an inhabited planet, all others must; and also that all planets must be inhabited; the argumentative value of these two chapters seems to lie in this that they annihilate one of the Essayist's points of unlikeness between our Sun and other Fixed Stars, inasmuch as it, together with so many of them, is one of a binary system: wherefore what is true of it, is true of them, et vice versa. He bases this proposition, viz., that our Sun is one of a binary system, on "high probability," from "the motion of our own system round a distant centre." The great truth of this motion, he says the Essayist "has completely misrepresented, foreseeing its influence on the mind as an argument for more worlds than one."‡ What the Essayist had said on the subject, was this: § he speaks of "the attempt to show that the Sun, carrying with it the whole solar system, is
One immense step more, however, and it is our last, brings to "the outskirts of creation," as the Essayist calls it, the Nebula: and here we find him once more confronted by his indefatigable and implacable opponent. We must therefore take our biggest and best mental telescope to behold these two Specks intellectual, so far off in infinitude, wrangling about
More Worlds than One, Ch. viii.. passim.
+ Ibid., p. 164. Lect. on Astron., 2d edit. (1849.)
a faint cloud vastly further off than themselves. Do you see how angry one of them looks, and how provokingly stolid the other? 'Tis all about the nature of that same cloud, or Nebula; and if we could only hear what they said, we might catch a chord or two of the music of the spheres! The Essayist is required, by his brother speck, to believe that the faintly-luminous patch at which they are gazing-a thousandth part of the visible breadth of our own Sun-contains in it more life than exists in as many such systems as the unassisted eye can see stars in the heavens on the clearest winter night: a view of the greatness of creation so stupendous, that the astounded speck, the Essayist, asks for a moment's time to consider the matter. "We are entitled to draw the conclusion," says the other, "that these Nebula are clusters of stars, at such an immense distance from our own system, that each star of which they are composed is the sun or centre of a system of planets; and that these planets are inhabited-like our Earth, the seat of vegetable, animal, and intellectual life:"* that all the Nebulæ are resolvable into stars; and appear as Nebulæ only because they are more distant than the region in which they can appear as stars. The conclusion, however, at which the Essayist arrives, after an elaborate examination of evidence, and especially of the latest discoveries in this dim and distant region by Sir John Herschell and the Earl of Rosse, is-that "Nebulæ are vast masses of incoherent or gaseous matter, of immense tenuity, diffused in forms more or less irregular, but all of them destitute of any regular system of solid moving bodies. So far, then," he concludes," as these Nebulæ are concerned, the improbability of their being inhabited appears to amount to the highest point that can be conceived. We may, by the indulgence of fancy, people the summer clouds, or the beams of the aurora borealis, with living beings of the same kind of substance as those bright appearances themselves; and in doing so, we are not making any bolder as
* More Worlds than One, p. 176. Essay, pp. 235-236.
sertion than when we stock the Nebule with inhabitants, and call them, in that sense, inhabited worlds." The Essayist contends that the argument for the vastness of the scheme of the Universe, suggested by the resolution of the Nebulæ, is found to be untenable-inasmuch as the greatest astronomers now agree in believing Nebula to have distances of the same order as Fixed Stars. Their filmy appearance is a true indication of a highly attenuated substance: so attenuated as to destroy all probability of their being inhabited worlds. With this opinion as to the tenuity of Nebulæ agrees the absence of all observed motion among their parts; while the extraordinary spiral arrangement of many of them, prove that nevertheless many of them really have motion, and suggests modes of calculating their tenuity, and showing how extreme it is. "It is probable," said Lord Rosse, in a paper which we ourselves heard him read not long ago, from the chair of the Royal Society, "that in the Nebular systems, motion exists. If we see a system with a distinct spiral arrangement, all analogy leads us to conclude that there has been motion; and that if there has been motion, that motion still continues.".. "Among the Nebula," he says, "there are vast numbers, much too faint to be sketched or measured with any prospect of advantage: the most powerful instruments we possess showing in them nothing of an organised structure, but merely a confused mass of nebulosity, of varying brightness."§ The Essayist makes powerful use, moreover, of Sir John Herschell's celebrated observation of the Magellanic Clouds, lying near the South Pole; exhibiting the coexistence, in a limited compass, and in indiscriminate position, of stars, clusters of stars, nebulæ regular and irregular, and nebular streaks and patches, things different not merely to us, but in themselves: nebulæ, side by side with stars and clusters of stars; nebulous matter resolvable, close to nebulous matter irresolvable;
the last and widest step by which the dimensions of the Universe have
Essay, p. 211. $ Dial., p. 18.
been expanded, in the notions of eager speculators, being checked by a completer knowledge, and a sager spirit of speculation. In discussing such matters as these, he finely observes" It is difficult to make men feel that so much ignorance can lie close to so much knowledge; to make them believe that they have been allowed to discover so much, and yet are not allowed to discover more."t In alluding to the Nebula, as subjects of our most powerful telescopic observation, the Essayist speaks in a tone of sarcasm concerning the "shining dots," the "lumps of light" which are rendered apparent amidst them asking, what are these lumps? (1.) How large? (2.) At what distances? (3.) Of what structure? (4.) Of what use?-adding, he must be a bold man who undertakes to answer the question, that each is a Sun, with attendant systems of planets. Sir David, exceedingly irate, says, "We accept the challenge, and appeal to our readers: "-(1.) The size of the dot, or lump, is large enough to be a Sun. (2.) He cannot answer this, for want of knowing the apparent distance between the centres of the dots.' (3.) Like our Sun-' It will consist of a luminous envelope, enclosing a dark nucleus.' (4.) Of no conceivable use, but to give light to planets, or to the solid nuclei of which they consist." In his turn, he asks the Essayist-what is the size, distance, structure, and use of the dots, upon his hypothesis? The Essayist, he observes, is silent; but in his Essay, he had said, distinctly enough, “Let us not wrangle about words. By all means let these dots be stars, if we know about what we are speaking: if a star mean, merely, a luminous dot in the sky. But that these stars shall resemble, in their nature, Stars of the First Magnitude, and that such stars shall resemble Our Sun, are surely very bold structures of assumption, to build on such a basis. Some nebulæ are resolvable into distinct points but what would it amount to? That the substance of all nebulæ is not continuous; separate, and
Essay, p. 214.
+ More Worlds than One, p. 215.
separable into distinct luminous elements:-nebulæ are, it would then seem, as it were of a curdled or granulated texture; they have run into lumps of light, or been formed originally of such lumps." And then follow some very ingenious and refined speculations, into which we have not space to enter; and indeed we may be well content with what we have done, having travelled from a tolerable depth in the crust of our own little planet, past planet after planet, star after star, till we reached the nebulous "outskirts of creation ;" accompanied by two Mentors of Infinitude,-whispering into our earone, that life, animal, intellectual, moral, was swarming around us at every step; the other, that that life ceased with our own Earth, as far as we were able to detect its existence, and giving us very solemn and mysterious reasons why it should be so.
Our Essayist, however, is not exhausted by the efforts he has made in his destructive career. If he be a "proud setter down" of cosmological systems, he determines, in turn, to be a "putter up" and so presents us with his own Theory of the Solar System; and an explanation of the mode in which all appearances in the Universe beyond may be reconciled with it. "It may serve " he says, "to confirm his argument, if he give a description of the system which shall continue and connect his views of the constitution and peculiarities as to physical circumstances of each of the planets. It will help us in our speculation, if we can regard the planets as not only a collection, but a scheme;-if we can give not an Enunciation only, but a Theory. Now, such a SCHEME, such a THEORY, appears to offer itself to us."§ The scope of this scheme, or theory, is, as we some time ago saw, to make our earth, in point of astronomical fact and reality, the largest Planetary Body in the solar system; its domestic hearth; the only part of the frame revolving round the Sun which has become a "WORLD." We must, however, make short work of it.
+Ibid., p. 216. $ Essay, p. 298.
The planets exterior to Mars-especially Jupiter and Saturn-appear spheres of water, or aqueous vapour. The Earth has a considerable atmosphere of air and of vapour; while on Venus or Mercury-so close to the sun-we see nothing of a gaseous or aqueous atmosphere; they and Mars differing little in density from the earth.
THE EARTH'S ORBIT, according to the Essayist's theory, IS THE TEMPERATE ZONE OF THE SOLAR SYSTEM, where only the play of hot and cold, moist and dry, is possible. Water and gases, clouds and vapours, form, mainly, the planets in the outer part of the solar system; while masses, such as result from the fusion of the most solid materials, lie nearer the Sun, and are found principally within the orbit of Jupiter. After a further exposition of his "theory" the Essayist observes that it agrees with the nebular hypothesis, so FAR as it applies to the Solar System; actly, and very sternly, repudiating that hypothesis as it applies to the Universe in general.* "If we allow ourselves," says he, "to speculate at all on physical grounds respecting the origin of the Earth, the hypothesis, that it has passed through a fluid and a gaseous condition, does not appear more extravagant than any other cosmogonical hypothesis: not even if we suppose that the other bodies of the Solar System have shared in the like changes. But, that all the stars and the nebulæ have gone, or are going through, a series of changes such as those by which the Solar System has been formed,-the nebular hypothesis, as it applies to the Universe in general, is precisely the doctrine which I here reject, giving my reasons."†
The whole of the Chapter devoted to "the Theory of the Solar System," is distinguished by remarkable ingenuity and orginality. It is, however, that entitled the Argument from Design, which, independently of all connection with the speculations of the author as already laid before our readers, is worthiest of consideration, by all interested in Natural Theology. It touches many topics which must have
occupied the profoundest thoughts of mankind, and touches them with the utmost caution and delicacy. In the 34th Section will be found a passage of singular boldness and imaginative eloquence; but liable, in our opinion, to serious misconception, and susceptible of misrepresentation-by those, at least, who are either unable, or indisposed, to weigh the entire chapter, and ascertain its real value and tendency. Some expressions have startled us not a little, when reflecting that they relate to the possible mode of action of Omniscient Omnipotence; and we shall be gratified by seeing them vindicated or explained in the next edition of his "Essay."
Each of our speculators closes his book with a chapter devoted to "The Future." The ideas of Sir David concerning the duration of the human race upon the earth (which Inspiration tells us is so awfully uncertain, and will be cut short suddenly-in a moment-in the twinkling of an eye), seem to be curiously definite; for we have seen that in his sixth chapter he states that "from the birth of man to the extinction of his race, the Solar System to which he belongs will have described but an infinitesimal arc in that grand cosmical orbit in which it is destined to move." Without pausing to ask who told him this, let us intimate, that in his final chapter he says that the scientific truths on which depends the plurality of worlds are intimately associated with the future destiny of man: he turns to the future of the sidereal systems, as the hallowed spots in which is to be spent his immortal existence. Scripture has not spoken articulately of the future locality of the blest; but Reason has combined the scattered utterances of Inspiration, and with an almost oracular voice declared that the Maker of the worlds will place in these the beings of his choice. In what region, reason does not determine; but it is impossible for man, with the light of Revelation as his guide, to doubt for a moment that on the celestial spheres his future is to be spent in lofty inquiries; social intercourse; the renewal of domestic ties; and in the service of his Almighty benefactor. The Christian's future,
* More Worlds than One, p. 315, and note.
+ Ibid., p. 315.