|
|
SCIENCE having practically diminished the moon's distance, and rendered distinct its elevations and depressions, it is natural for " those obstinate questionings of sense and outward things " to urge the inquiry, Is the moon inhabited? This question it is easier to ask than to answer. It has been a mooted point for many years, and our wise men of the west seem still disposed to give it up, or, at least, to adjourn its decision for want of evidence. Of "guesses at truth" there have been a great multitude, and of dogmatic assertions not a few; but demonstrations are things which do not yet appear. We now take leave to report progress, and give the subject a little ventilation. We do not expect to furnish an Ariadne's thread, but we may hope to find some indication of the right way out of this labyrinth of uncertainty. Veritas nihil veretur nisi abscondi: or, as the German proverb says, "Truth creeps not into corners"; its life is the light.
But before we advance a single step, we desire to preclude all misunderstanding on one point, by distinctly avowing our conviction that the teachings of Christian theology are not at all involved in the issue of this discussion, whatever it may prove. Infinite harm has been done by confusing the religion of science with the science of religion. Religion is a science, and science is a religion; but they are not identical. Philosophy ought to be pious, and piety ought to be philosophical; but philosophy and piety are two quantities and qualities that may dwell apart, though, happily, they may also be found in one nature. Each has its own faculties and functions; and in our present investigation, religion has nothing more to do than to shed the influence of reverence, humility, and teachableness over the scientific student as he ponders his problem and works out the truth. In this, and in kindred studies, we may yield without reluctance what a certain professor of religion concedes, and grant without grudging what a certain professor of science demands. Dr. James Martineau says, "In so far as Church belief is still committed to a given kosmogony and natural history of man, it lies open to scientific refutation"; and again, "The whole history of the Genesis of things Religion must unconditionally surrender to the Sciences."421 In this we willingly concur, for science ought to be, and will be, supreme in its own domain. Bishop Temple does "not hesitate to ascribe to Science a clearer knowledge of the true interpretation of the first chapter of Genesis, and to scientific history a truer knowledge of the great historical prophets. Science enters into Religion, and the believer is bound to recognise its value and make use of its services."422 Then, to quote the professor of science, Dr. John Tyndall says. "The impregnable position of science may be described in a few words. We claim, and we shall wrest from Theology, the entire domain of cosmological theory."423 We wish the eloquent professor all success.
It was not the spirit of primitive Christianity, but the spirit of priestly ignorance, intolerance, and despotism, which invaded the territory of natural science; and if those who are its rightful lords can recover the soil, we bid them heartily, God speed! We have been driven to these remarks by a twofold impulse. First, we can never forget the injury that has been inflicted on science by the oppositions of a headless religion; any more than we can forget the injury which has been inflicted on religion by the oppositions of a heartless science. Secondly, we have seen this very question of the inhabitation of the planets and satellites rendered a topic of ridicule for Thomas Paine, and an inviting theme for raillery to others of sophistical spirit, by the way in which it has been foolishly mixed up with sacred or spiritual concerns. Surely, the object of God in the creation of our terrestrial race, or the benefits of the death of Jesus Christ, can have no more to do with the habitability of the moon, than the doctrine of the Trinity has to do with the multiplication table and the rule of three, or the hypostatical union with the chemical composition of water and light. Having said thus much of compulsion, we return, not as ministers in the temple of religion so much as students in the school of science, to consider with docility the question in dispute, Is the moon inhabited?
Three avenues, more or less umbrageous, are open to us; all of which have been entered.
They may be named observation, induction, and analogy. The first, if we could pursue it, would explicate the enigma at once. The second, if clear, would satisfy our reason, which, in such a matter, might be equivalent to sight. And the third might conduct us to a shadow which would "prove the substance true." We begin by dealing briefly with the argument from observation. Here our data are small and our difficulties great. One considerable inconvenience in the inquiry is, of course, the moon's distance. Though she is our next-door neighbour in the many-mansioned universe, two hundred and thirty-seven thousand miles are no mere step heavenward. Transit across the intervenient space being at present impracticable, we have to derive our most enlarged views of this "spotty globe" from the "optic glass." But this admirable appliance, much as it has revealed, is thus far wholly inadequate to the solution of our mystery. Robert Hooke, in the seventeenth century, thought that he could construct a telescope with which we might discern the inhabitants of the moon life-size-seeing them as plainly as we see the inhabitants of the earth. But, alas! the sanguine mathematician died in his sleep, and his dream has not yet come true.
Since Hooke's day gigantic instruments have been fitted up, furnished with all the modern improvements which could be supplied through the genius or generosity of such astronomers as Joseph Fraunhofer and Sir William Herschel, the third Earl of Rosse and the fourth Duke of Northumberland. But all of these worthy men left something to be done by their successors. Consequently, not long since, our scientists set to work to increase their artificial eyesight. The Rev. Mr. Webb tells us that "the first 'Moon Committee' of the British Association recommended a power of 1,000." But he discourages us if we anticipate large returns; for he adds: "Few indeed are the instruments or the nights that will bear it; but when employed, what will be the result? Since increase of magnifying is equivalent to decrease of distance, we shall see the moon as large (though not as distinct) as if it were 240 miles off, and any one can judge what could be made of the grandest building upon earth at that distance."424 If therefore we are to see the settlement of the matter in the speculum of a telescope, it may be some time before we have done with what Guillemin calls "the interesting, almost insoluble question, of the existence of living and organized beings on the surface of the satellite of our little earth."425 Some cynic may interpose with the quotation,--
"But optics sharp it needs, I ween,
To see what is not to be seen."426
True, but it remains to be shown that there is nothing to be seen beyond what we see. We are not prepared to deny the existence of everything which our mortal eyes may fail to trace. Four hundred years ago all Europe believed that to sail in search of a western continent was to wish "to see what is not to be seen"; but a certain Christopher Columbus went out persuaded of things not seen as yet, and having embarked in faith he landed in sight. The lesson must not be lost upon us.
"There are more things in heaven and earth,
Horatio,
Than are dreamt of in your philosophy."
Because we cannot now make out either habitations or habitants on the moon, it does not necessarily follow that the night will never come when, through some mightier medium than any ever yet constructed or conceived, we shall descry, beside mountains and valleys, also peopled plains and populous cities animating the fair features of this beautiful orb. One valuable auxiliary of the telescope, destined to play an important part in lunar discovery, must not be overlooked. Mr. Norman Lockyer says, "With reference to the moon, if we wish to map her correctly, it is now no longer necessary to depend on ordinary eye observations alone; it is perfectly clear that by means of an image of the moon, taken by photography, we are able to fix many points on the lunar surface."427[paragraph continues]
With telescopic and photographic lenses in skilled hands, and a wealth of inventive genius in fertile brains, we can afford to wait a long while before we close the debate with a final negative.
In the meantime, eyes and glasses giving us no satisfaction, we turn to scientific induction. Speculation is a kind of mental mirror, that before now has anticipated or supplemented the visions of sense. Not being practical astronomers ourselves, we have to follow the counsel of that unknown authority who bids us believe the expert. But expertness being the fruit of experience, we may be puzzled to tell who have attained that rank. We will inquire, however, with due docility, of the oracles of scientific research. It is agreed on all sides that to render the moon habitable by beings at all akin with our own kind, there must be within or upon that body an atmosphere, water, changing seasons, and the alternations of day and night. We know that changes occur in the moon, from cold to heat, and from darkness to light. But the lunar day is as long as 291 of ours; so that each portion of the surface is exposed to, or turned from, the sun for nearly 14 days.
This long exposure produces excessive heat, and the long darkness excessive cold. Such extremities of temperature are unfavourable to the existence of beings at all like those living upon the earth, especially if the moon be without water and atmosphere. As these two desiderata seem indispensable to lunar inhabitation, we may chiefly consider the question, Do these conditions exist? If so, inductive reasoning will lead us to the inference, which subsequent experience will strengthen, that the moon is inhabited like its superior planet. But if not, life on the satellite similar to life on the earth, is altogether improbable, if not absolutely impossible.
The replies given to this query will be by no means unanimous. But, for the full understanding of the state of the main question, and to assist us in arriving at some sort of verdict, we will hear several authorities on both sides of the case. The evidence being cumulative, we pursue the chronological order, and begin with La Place. He writes: "The lunar atmosphere, if any such exists, is of an extreme rarity, greater even than that which can be produced on the surface of the earth by the best constructed air-pumps. It may be inferred from this that no terrestrial animal could live or respire at the surface of the moon, and that if the moon be inhabited, it must be by animals of another species."428 This opinion, as Sir David Brewster points out, is not that the moon has no atmosphere, but that if it have any it is extremely attenuated. Mr. Russell Hind's opinion is similar with respect to water. He says: "Earlier selenographists considered the dull, grayish spots to be water, and termed them the lunar seas, bays, and lakes. They arc so called to the present day, though we have strong evidence to show that if water exist at all on the moon, it must be in very small quantity."429 Mr. Grant tells us that "the question whether the moon be surrounded by an atmosphere has been much discussed by astronomers. Various phenomena are capable of indicating such an atmosphere, but, generally speaking, they are found to be unfavourable to its existence, or at all events they lead to the conclusion that it must be very inconsiderable."430 Humboldt thinks that Schroeter's assumptions of a lunar atmosphere and lunar twilight are refuted, and adds: "If, then, the moon is without any gaseous envelope, the entire absence of any diffused light must cause the heavenly bodies, as seen from thence, to appear projected against a sky almost black in the day-time. No undulation of air can there convey sound, song, or speech. The moon, to our imagination, which loves to soar into regions inaccessible to full research, is a desert where silence reigns unbroken."431 Dr. Lardner considers it proven "that there does not exist upon the moon an atmosphere capable of reflecting light in any sensible degree," and also believes that "the same physical tests which show the non-existence of an atmosphere of air upon the moon are equally conclusive against an atmosphere of vapour."432 Mr. Breen is more emphatic. He writes: "In the want of water and air, the question as to whether this body is inhabited is no longer equivocal. Its surface resolves itself into a sterile and inhospitable waste, where the lichen which flourishes amidst the frosts and snows of Lapland would quickly wither and die, and where no animal with a drop of blood in its veins could exist."433 The anonymous author of the Essay on the Plurality of Worlds announces that astronomers are agreed to negative our question without dissent. We shall have to manifest his mistake. His words are: "Now this minute examination of the moon's surface being possible, and having been made by many careful and skilful astronomers, what is the conviction which has been conveyed to their minds with regard to the fact of her being the seat of vegetable or animal life? Without exception, it would seem, they have all been led to the belief that the moon is not inhabited; that she is, so far as life and organization are concerned, waste and barren, like the streams of lava or of volcanic ashes on the earth, before any vestige of vegetation has been impressed upon them; or like the sands of Africa, where no blade of grass finds root."434
Robert Chambers says: "It does not appear that our satellite is provided with an atmosphere of the kind found upon earth; neither is there any appearance of water upon the surface. . . . These characteristics of the moon forbid the idea that it can be at present a theatre of life like the earth, and almost seem to declare that it never can become so."435 Schoedler's opinion is concurrent with what has preceded. He writes: "According to the most exact observations it appears that the moon has no atmosphere similar to ours, that on its surface there are no great bodies of water like our seas and oceans, so that the existence of water is doubtful. The whole physical condition of the lunar surface must, therefore, be so different from that of our earth, that beings organized as we are could not exist there."436 Another German author says: "The observations of Fraunhofer (1823), Brewster and Gladstone (1860), Huggins and Miller, as well as Janssen, agree in establishing the complete accordance of the lunar spectrum with that of the sun.
In all the various portions of the moon's disk brought under observation, no difference could be perceived in the dark lines of the spectrum, either in respect of their number or relative intensity. From this entire absence of any special absorption lines, it must be concluded that there is no atmosphere in the moon, a conclusion previously arrived at from the circumstance that during an occultation no refraction is perceived on the moon's limb when a star disappears behind the disk."437 Mr. Nasmyth follows in the same strain. Holding that the moon lacks air, moisture, and temperature, he says, "Taking all these adverse conditions into consideration, we are in every respect justified in concluding that there is no possibility of animal or vegetable life existing on the moon, and that our satellite must therefore be regarded as a barren world."438 A French astronomer holds a like opinion, saying: "There is nothing to show that the moon possesses an atmosphere; and if there was one, it would be perceptible during the occultations of the stars and the eclipses of the sun. It seems impossible that, in the complete absence of air, the moon can be peopled by beings organized like ourselves, nor is there any sign of vegetation or of any alteration in the state of its surface which can be attributed to a change of seasons."439 On the same side Mr. Crampton writes most decisively, "With what we do know, however, of our satellite, I think the idea of her being inhabited may be dismissed summarily; i.e. her inhabitation by intelligent beings, or an animal creation such as exist here."440 And, finally, in one of Maunder's excellent Treasuries, we read of the moon, "She has no atmosphere, or at least none of sufficient density to refract the rays of light as they pass through it, and hence there is no water on her surface; consequently she can have no animals like those on our planet, no vegetation, nor any change of seasons."441 These opinions, recorded by so many judges of approved ability and learning, have great weight; and some may regard their premisses and conclusions as irresistibly cogent and convincing. The case against inhabitation is certainly strong. But justice is impartial. Audi alteram partem.
Judges of equal erudition will now speak as respondents. We go back to the seventeenth century, and begin with a work whose reasoning is really remarkable, seeing that it is nearly two hundred and fifty years since it was first published. We refer to the Discovery of a New World by John Wilkins, Bishop of Chester; in which the reverend philosopher aims to prove the following propositions:--"1. That the strangeness of this opinion (that the moon may be a world) is no sufficient reason why it should be rejected; because other certain truths have been formerly esteemed as ridiculous, and great absurdities entertained by common consent. 2. That a plurality of worlds does not contradict any principle of reason or faith. 3. That the heavens do not consist of any such pure matter which can privilege them from the like change and corruption, as these inferior bodies are liable unto. 4. That the moon is a solid, compacted, opacous body. 5. That the moon hath not any light of her own. 6. That there is a world in the moon, hath been the direct opinion of many ancient, with some modern mathematicians; and may probably be deduced from the tenets of others. 9. That there are high mountains, deep valleys, and spacious plains in the body of the moon. 10. That there is an atmosphœra, or an orb of gross vaporous air, immediately encompassing the body of the moon. 13. That 'tis probable there may be inhabitants in this other world; but of what kind they are, is uncertain."442 We go on to 1686, and listen to the French philosopher, Fontenelle, in his Conversations with the Marchioness. "'Well, madam,' said I, 'you will not be surprised when you hear that the moon is an earth too, and that she is inhabited as ours is.' 'I confess,' said she, 'I have often heard talk of the world in the moon, but I always looked upon it as visionary and mere fancy.' 'And it may be so still,' said I. 'I am in this case as people in a civil war, where the uncertainty of what may happen makes them hold intelligence with the opposite party; for though I verily believe the moon is inhabited, I live civilly with those who do not believe it; and I am still ready to embrace the prevailing opinion.
But till the unbelievers have a more considerable advantage, I am for the people in the moon.'"443 Whatever may be thought of his philosophy, no one could quarrel with the Secretary of the Academy on the score of his politeness or his prudence. A more recent and more reliable authority appears in Sir David Brewster. He tells us that "MM. Mädler and Beer, who have studied the moon's surface more diligently than any of their predecessors or contemporaries, have arrived at the conclusion that she has an atmosphere." Sir David himself maintains that "every planet and satellite in the solar system must have an atmosphere."444 Bonnycastle, whilom professor of mathematics in the Royal Military Academy, Woolwich, writes: "Astronomers were formerly of opinion that the moon had no atmosphere, on account of her never being obscured by clouds or vapours; and because the fixed stars, at the time of an occultation, disappear behind her instantaneously, without any gradual diminution of their light.
But if we consider the effects of her days and nights, which are near thirty times as long as with us, it may be readily conceived that the phenomena of vapours and meteors must be very different. And besides, the vaporous or obscure part of our atmosphere is only about the one thousand nine hundred and eightieth part of the earth's diameter, as is evident from observing the clouds, which are seldom above three or four miles high; and therefore, as the moon's apparent diameter is only about thirty-one minutes and a half, or one thousand eight hundred and ninety seconds, the obscure part of her atmosphere, supposing it to resemble our own, when viewed from the earth, must subtend an angle of less than one second; which is so small a space, that observations must be extremely accurate to determine whether the supposed obscuration takes place or not."445 Dr. Brinkley, at one time the Astronomer-Royal of Ireland, writes: "Many astronomers formerly denied the existence of an atmosphere at the moon; principally from observing no variation of appearance on the surface, like what would take place, did clouds exist as with us; and also, from observing no change in the light of the fixed stars on the approach of the dark edge of the moon. The circumstance of there being no clouds, proves either that there is no atmosphere similar to that of our earth, or that there are no waters on its surface to be converted into vapour; and that of the lustre of the stars not being changed, proves that there can be no dense atmosphere.
But astronomers now seem agreed that an atmosphere does surround the moon, although of small density when compared with that of our earth. M. Schroeter has observed a small twilight in the moon, such as would arise from an atmosphere capable of reflecting the rays at the height of about one mile."446 Dr. Brinkley is inaccurate in saying that astronomers are agreed as to the lunar atmosphere. Like students in every other department of inquiry, spiritual as well as physical, they fail at present to see "eye to eye"; which is not surprising, seeing that the eye is so restricted, and the object so remote.
Dr. Dick, whose productions have done much to popularize the study of the heavens, and to promote its reverent pursuit, says: "On the whole it appears most probable that the moon is surrounded with a fluid which serves the purpose of an atmosphere; although this atmosphere, as to its nature, composition, and refractive power, may be very different from the atmosphere which surrounds the earth. It forms no proof that the moon, or any of the planets, is destitute of an atmosphere, because its constitution, its density, and its power of refracting the rays of light are different from ours. An atmosphere may surround a planetary body, and yet its parts be so fine and transparent that the rays of light, from a star or any other body, may pass through it without being in the least obscured, or changing their direction. In our reasonings on this subject, we too frequently proceed on the false principle, that everything connected with other worlds must bear a resemblance to those on the earth."447 Mr. Neison, who has written one of the latest contributions to the science of selenography, says, "Of the present non-existence of masses of water upon the surface of the moon, there remains no doubt, though no evidence of its entire absence from the lunar crust can be adduced; and similarly, many well-established facts in reference to the moon afford ample proof of the non-existence of a lunar atmosphere, having a density equal to, or even much less than, that of the earth; but of the absence of an atmosphere, whose mass should enable it to play an important part in the moulding of the surface of the moon, and comparable almost to that of the terrestrial atmosphere, in their respective ratios to the masses of their planets, little, if any, trustworthy evidence exists." On another page of the same work, the author affirms "that later inquiries have shown that the moon may possess an atmosphere that must be regarded as fully capable of sustaining various forms of vegetation of even an advanced type; and, moreover, it does not appear how it can justly be questioned that the lunar surface in favourable positions may yet retain a sufficiency of moisture to support vegetation of many kinds; whilst in a very considerable portion of the entire surface of the moon, the temperature would not vary sufficiently to materially affect the existence of vegetable life."448 Some of these writers may appear to be travelling rather too fast or too far, and their assumptions may wear more of the aspect of plausibility than of probability. But on their atmospheric and aqueous hypothesis, vegetation in abundance is confessedly a legitimate consequence. If a recent writer has liberty to condense into a sentence the conclusion from the negative premiss in the argument by saying, "As there is but a little appearance of water or air upon the moon, the conclusion has been inferred that there exists no vegetable or animal life on that globe,"449 other writers, holding opposite views of the moon's physical condition, may be allowed to expatiate on the luxuriant life which an atmosphere with water and temperature would undoubtedly produce.
Mr. Proctor's tone is temperate, and his language that of one who is conscious with Hippocrates that "art is long and life is short." He says, in one of his contributions to lunar science, "It may safely be asserted that the opportunities presented during the life of any single astronomer for a trustworthy investigation of any portion of the moon's surface, under like conditions, are few and far between, and the whole time so employed must be brief, even though the astronomer devote many more years than usual to observational research."450 This prepares us to find in another of the same author's works the following suggestive sentence: "With regard to the present habitability of the moon, it may be remarked that we are not justified in asserting positively that no life exists upon her surface. Life has been found under conditions so strange, we have been so often mistaken in assuming that here certainly, or there, no living creatures can possibly exist, that it would be rash indeed to dogmatise respecting the state of the moon in this respect."451 Narrien, one of the historians of the science, may be heard, though his contribution might be cast into either scale. He writes: "The absence of those variations of light and shade which would be produced by clouds floating above her surface, and the irregularities of the ground, visible at the bottom and on the sides of her cavities, have given reason to believe that no atmosphere surrounds her, and that she is destitute of rivers and seas. Such are the opinions generally entertained concerning the moon; but M. Schroeter, a German astronomer, ventures to assert that our satellite is the abode of living and intellectual beings; he has perceived some indications of an atmosphere which, however, he admits, cannot exceed two miles in height, and certain elevations which appear to him to be works of art rather than of nature. He considers that a uniformity of temperature must be produced on her surface by her slow rotation on her axis, by the insensible change from day to night, and the attenuated state of her atmosphere, which is never disturbed by storms; and that light vapours, rising from her valleys, fall in the manner of a gentle and refreshing dew to fertilize her fields."452
Dr. H. W. M. Olbers is fully persuaded "that the moon is inhabited by rational creatures, and that its surface is more or less covered with a vegetation not very dissimilar to that of our own earth." Dr. Gruithuisen, of Munich, maintains that he has descried through his large achromatic telescope "great artificial works in the moon erected by the lunarians," which he considers to be "a system of fortifications thrown up by the selenitic engineers." We should have scant hope of deciding the dispute by the dicta of the ancients, were these far more copious than we find them to be. Yet reverence for antiquity may justify our quoting one of the classic fathers. Plutarch says, "The Pythagoreans affirme, that the moone appeereth terrestriall, for that she is inhabited round about, like as the earth wherein we are, and peopled as it were with the greatest living creatures, and the fairest plants." Again, "And of all this that hath been said (my friend Theon) there is nothing that doth proove and show directly, this habitation of men in the moon to be impossible."453 Here we close the argument based on induction, and sum up the evidence in our possession. On the one hand, several scientific men, whose names we need not repeat, having surveyed the moon, deny it an atmosphere, water, and other conditions of life. Consequently, they disbelieve in its inhabitation, solely because they consider the fact undemonstrable; none of them being so unscientific as to believe it to be absolutely impossible. On the other hand, we have the valuable views of Mädler and Beer, whose lunar labours are unsurpassed, and whose map of the moon is a marvel and model of advanced selenography. They do not suppose the conditions on our satellite to be exactly what they are on this globe. In their own words, the moon is "no copy of the earth, much less a colony of the same." They merely believe her to be environed with air, and thus habitable. And when we recall our own Sir David Brewster, Professor Bonnycastle, Dr. Brinkley, Dr. Dick, Mr. Neison, and Mr. Proctor; and reckon with them the continental astronomers, Dr. Gruithuisen, Dr. Olbers, and Schroeter, all of whom attempted to fix the idea of planetary inhabitation on the popular mind, we must acknowledge that they, with their opponents, have a strong claim on our attention. The only verdict we are able just now to render, after hearing these conflicting testimonies, is the Scotch one, Not proven. We but append the legal indorsement ignoramus, we do not know. The subject must remain sub judice; but what we know not now, we hope to know hereafter.
Having interrogated sense and science, with the solution of our enigma anything but complete, we resort last of all to the argument from analogy. If this can illumine the obscurity, it will all be on the positive side of the inquiry. At present the question resembles a half-moon: analogy may show that the affirmative is waxing towards a full-orbed conviction. We open with Huyghens, a Dutch astronomer of note, who, while he thinks it certain "that the moon has no air or atmosphere surrounding it as we have," and "cannot imagine how any plants or animals whose whole nourishment comes from fluid bodies, can thrive in a dry, waterless, parched soil," yet asks, "What, then, shall this great ball be made for; nothing but to give us a little weak light in the night time, or to raise our tides in the sea? Shall not we plant some people there that may have the pleasure of seeing our earth turn upon its axis, presenting them sometimes with a prospect of Europe and Africa, and then of Asia and America; sometimes half and sometimes full?"454 Ray was "persuaded that this luminary doth serve many ends and uses, especially to maintain the creatures which in all likelihood breed and inhabit there."455 Swedenborg's ipse dixit ought to convince the most incredulous; for he speaks "from what has been heard and seen." Thus he says: "That there are inhabitants in the moon is well known to spirits and angels, and in like manner that there are inhabitants in the moons or satellites which revolve about Jupiter and Saturn. They who have not seen and discoursed with spirits coming from those moons still entertain no doubt but there are men inhabiting them, because they are earths alike with the planets, and wherever an earth is, there are men inhabitants; for man is the end for which every earth was created, and nothing was made by the great Creator without an end."456 If any are still sceptical, Sir William Herschel, an intellectual light of no mean magnitude, may reach them. He writes: "While man walks upon the ground, the birds fly in the air, and fishes swim in water, we can certainly not object to the conveniences afforded by the moon, if those that are to inhabit its regions are fitted to their conditions as well as we on this globe arc to ours. An absolute or total sameness seems rather to denote imperfections, such as nature never exposes to our view; and, on this account, I believe the analogies that have been mentioned fully sufficient to establish the high probability of the moon's being inhabited like the earth."457
The voice of Dr. Dwight, the American theologian, will not be out of harmony here. In discoursing of the starry heavens, he says of the planets: "Of these inferior worlds, the moon is one; and to us, far the most interesting. How many important purposes which are known does this beautiful attendant of our earth continually accomplish! How many more, in all probability, which are hitherto unknown, and which hereafter may be extensively disclosed to more enlightened, virtuous, and happy generations of men! At the same time, it is most rationally concluded that intelligent beings in great multitudes inhabit her lucid regions, being far better and happier than ourselves."458 Whewell's Bridgewater Treatise will furnish us a fitting quotation. "The earth, the globular body thus covered with life, is not the only globe in the universe. There are, circling about our own sun, six others, so far as we can judge, perfectly analogous in their nature: besides our moon and other bodies analogous to it. No one can resist the temptation to conjecture, that these globes, some of them much larger than our own, are not dead and barren:--that they are, like ours, occupied with organization, life, intelligence."459 In a most eloquent passage, Dr. Chalmers, who will always be heard with admiration, exclaims: "Who shall assign a limit to the discoveries of future ages? Who shall prescribe to science her boundaries, or restrain the active and insatiable curiosity of man within the circle of his present acquirements? We may guess with plausibility what we cannot anticipate with confidence. The day may yet be coming when our instruments of observation shall be inconceivably more powerful. They may ascertain still more decisive points of resemblance. They may resolve the same question by the evidence of sense which is now so abundantly convincing by the evidence of analogy. They may lay open to us the unquestionable vestiges of art, and industry, and intelligence.
We may see summer throwing its green mantle over those mighty tracts, and we may see them left naked and colourless after the flush of vegetation has disappeared. In the progress of years or of centuries, we may trace the hand of cultivation spreading a new aspect over some portion of a planetary surface. Perhaps some large city, the metropolis of a mighty empire, may expand into a visible spot by the powers of some future telescope. Perhaps the glass of some observer, in a distant age, may enable him to construct the map of another world, and to lay down the surface of it in all its minute and topical varieties. But there is no end of conjecture; and to the men of other times we leave the full assurance of what we can assert with the highest probability, that yon planetary orbs are so many worlds, that they teem with life, and that the mighty Being who presides in high authority over this scene of grandeur and astonishment has there planted the worshippers of His glory."460
How fine is this outburst of the great Scotch orator! He spoke as one inspired with prophetic foreknowledge; for in less than twenty years after this utterance, Beer and Mädler published their splendid Mappe Selenographica, or map of the moon; and photography offered its aid to the fuller delineation of our silvery satellite. Who can tell what the last fifteen years of this eventful century may develop in the same direction? Verily these intuitions of reason seem often favoured with an apocalypse of coming disclosures; and, if we may venture to adopt with slight alteration a sentence of Shelley, we will say: "It is impossible to read the compositions of the most celebrated writers of the present day without being startled with the electric life which burns within their words. They measure the circumference and sound the depths of nature with a comprehensive and all-penetrating spirit, and they are themselves perhaps the most sincerely astonished at its manifestations; for it is less their spirit than the spirit of the age." The poets of science, in their analogies, are "the hierophants of an unapprehended inspiration; the mirrors of the gigantic shadows which futurity casts upon the present."461 Equally noble with the language of Chalmers is a paragraph which we have extracted from a work by that scholarly writer, Isaac Taylor. He says: "There are two facts, each of which is significant in relation to our present subject, and of which the first has long been understood, while the latter (only of late ascertained) is every day receiving new illustrations; namely, that our planet is, in no sense, of primary importance in the general system, or entitled, by its magnitude, or its position, or its constitution, to be considered as exerting any peculiar influence over others, or as the object of more regard than any others. This knowledge of our real place and value in the universe is a very important consequence of our modern astronomy, and should not be lost sight of in any of our speculations. But then it is also now ascertained that the great laws of our own planet, and of the solar system to which it belongs, prevail in all other and the most remote systems, so as to make the visible universe, in the strictest sense, ONE SYSTEM--indicating one origin and showing the presence of one Controlling Power. Thus the law of gravitation, with all the conditions it implies, and the laws of light, are demonstrated to be in operation in regions incalculably remote; and just so far as the physical constitution of the other planets of our system can be either traced, or reasonably conjectured, it appears that, amid great diversities of constitution, the same great principles prevail in all; and therefore our further conjecture concerning the existence of sentient and rational life in other worlds is borne out by every sort of analogy, abstract and physical; and this same rule of analogy impels us to suppose that rational and moral agents, in whatever world found, and whatever diversity of form may distinguish them, would be such that we should soon feel at home in their society, and able to confer with them, to communicate knowledge to them, and to receive knowledge from them. Neither truth nor virtue is local; nor can there be wisdom and goodness in one planet, which is not wisdom and goodness in every other."462
The writer of the Plurality of Worlds, a little work distinct from the essay already quoted, vigorously vindicates "the deeply cherished belief of some philosophers, and of many Christians, that our world, in its present state, contains the mere embryo of intelligent, moral, and religious happiness; that the progress of man in his present state is but the initiation of an interminable career of glory; and that his most widely extended associations are a preparation for as interminably an intercourse with the whole family of an intelligent universe."463 Dr. Arnott may add a final word, a last link in this evidential chain of analogy. He writes: "To think, as our remote forefathers did, that the wondrous array of the many planets visible from this earth serve no purpose but to adorn its nocturnal sky, would now appear absurd indeed; but whether they are inhabited by beings at all resembling the men of this earth, we have not the means of knowing. All the analogies favour the opinion that they are the abodes of life and its satisfactions. On this earth there is no place so hot or so cold, so illumined or so dark, so dry or so wet, but that it has creatures constituted to enjoy life there."464
Here our long list of learned authorities shall terminate. We have strung together a large number of citations, and have ourselves furnished only the string. Indeed, what more have amateurs that they can do? For, as Pope puts it,--
"Who shall decide, when doctors disagree,
And soundest casuists doubt, like you and me?
Besides, astronomy is no child's play, nor are its abstruse problems to be mastered by superficial meddlers. "Its intricacy," as Narrien reminds us, "in the higher departments, is such as to render the processes unintelligible to all but the few distinguished persons who, by nature and profound application to the subject, are qualified for such researches."465 But if professionals must be summoned as witnesses, ordinary men may sit as jurors. This function we have wished to fufil; and we avow ourselves considerably perplexed, though not in despair. We hoped that after a somewhat exhaustive examination, we might be able to state the result with an emphasis of conviction. This we find impossible; but we can affirm on which side the evidence appears to preponderate, and whither, we rest assured, further light will lead our willing feet. The conclusion, therefore, of the whole matter is: we cannot see any living creatures on the moon, however long we strain our eyes. No instrument has yet been constructed that will reveal the slightest vestige of inhabitation. Consequently, the actual evidence of sense is all against us, and we resign it without demur. This point, being settled, is dismissed.
Next, we reconsider the results of scientific study, and are strongly inclined to think the weight of testimony favours the existence of a thin atmosphere, at least some water, and a measure of light and shade in succession. These conditions must enable vegetables and animals to exist upon its surface, though their constitution is in all probability not analogous with that of those which are found upon our earth. But to deny the being of inhabitants of some kind, even in the absence of these conditions, we submit would be unphilosophical, seeing that the Power which adapted terrestrial life to terrestrial environments could also adapt lunar life to the environments in the moon. We are seeking no shelter in the miraculous, nor do we run from a dilemma to the refuges of religion. Apart from our theological belief in the potency of the Creator and Controller of all worlds, we simply regard it as illogical and inconclusive to argue that because organization, life, and intelligence obtain within one sphere under one order of circumstances, therefore the same order obtains in every other sphere throughout the system to which that one belongs. The unity of nature is as clear to us as the unity of God; but unity is not uniformity. We view the whole creation as we view this world; the entire empire as we view this single province,
"Where order in variety we see,
And where, though all things differ, all agree."
And, finally, as analogy is unreservedly on the side of the occupation of every domain in creation, by some creatures who have the dominion, we cannot admit the probability that the earth is the only tenement with tenants: we must be confirmed in our judgment that the sun and the planets, with their moons, ours of course included, are neither blank nor barren, but abodes of variously organized beings, fitted to fulfil the chief end of all noble existence: the enjoyment of life, the effluence of love, the good of all around and the glory of God above.
This article, that the moon is inhabited, may therefore form a clause of our scientific creed; not to be held at any hazard, as a matter of life or death, or a test of communion, but to be maintained subject to corrections such as future elucidation may require. We believe that we are justified by science, reason, and analogy; and confidently look to be further justified by verification. We accept many things as matters of faith, which we have not fully ascertained to be matters of fact; but "faith is the assurance of things hoped for, the proving of things not seen." By double entry the books of science are kept, by reasoning and demonstration: when future auditors shall examine the accounts of the moon's inhabitation, we are persuaded that the result of our reckoning will be found to be correct.
If any would charge us with a wish to be wise above what is written, we merely reply: There are unwritten revelations which are nevertheless true.
Besides, we are not sure that at least an intimation of other races than those of the earth is not already on record. Not to prove any position, but to check obstructive criticism, we refer to the divine who is said to have witnessed in magnificent apocalypse some closing scenes of the human drama. If he also heard in sublime oratorio a prelude of this widely extended glory, our vision may not be a "baseless fabric." After the quartettes of earth, and the interludes of angels, came the grand finale, when every creature which is in heaven, as well as on the earth, was heard ascribing "Blessing and honour and glory and power to Him who sitteth upon the throne." Assuredly, our conception of a choir worthy to render that chorus is not of an elect handful of "saints," or contracted souls, embraced within any Calvinistic covenant, but of an innumerable multitude of ennobled, purified, and expanded beings, convoked from every satellite and planet, every sun and star, and overflowing with gratitude and love to that universal Father of lights, with whom is no parallax, nor descension, and who kindled every spark of life and beauty that in their individual and combined lustre He might reflect and repeat His own ineffable blessedness.