God's glory in the heavens/The Uses Of The Moon
Moon in Quarter.
V.
THE USES OF THE MOON.
M. Comte, while forced to admit that we do derive some benefit from the moon, scouts the idea that there was any anterior design to make it useful to us. His views on the religious aspect are given in the following passage:—"To those who are strangers to the study of the heavenly bodies, although frequently masters of the other parts of natural philosophy, astronomy has still the reputation of being an eminently religions science, as if the famous verse, 'The heavens declare the glory of God,' still preserved all its value. To minds early familiarised with true philosophical astronomy, the heavens declare no other glory than that of Hipparchus, of Kepler, of Newton, and of all those who have aided in establishing their laws. It is, however, certain, as I have shewn, that all real science is in radical and necessary opposition to all theology, and this characteristic is more decided in astronomy than anywhere else, just because astronomy is, so to speak, more a science than any other. No other has given more terrible shocks to the doctrine of final causes, generally regarded by the moderns as the indispensable basis of every religious system, although, in reality, it has been the consequence of them. The simple knowledge of the movement of the earth must have destroyed the prime and real foundation of this doctrine—the idea of the universe subordinated to the earth, and consequently to man. Besides, the accurate exploration of our system could not but dispel that blind and unlimited wonder which the general order of nature inspired, by shewing, in the most sensible manner, and in various respects, that the elements of this system are certainly not disposed in the most advantageous manner and science permits us easily to conceive a happier arrangement."
We shall not stop to notice the tone of arrogant assumption in the statement that every philosophic astronomer must be an atheist. We mean only to advert to the argument here employed to banish a Divine Intelligence from the universe. It amounts to this—that, as we can conceive a better arrangement, there could have been no intelligence in the original adjusting of the arrangement. Let us take the moon for illustration. Laplace fancied he could improve on the solar system by placing the moon differently. He endeavours to shew that if the purpose of the moon was to give light to the earth, this could be accomplished far more effectually if the moon was so situated that it revolved round the earth in the same time that the earth revolved round the sun. In that case, she would be always full, and her light would be enjoyed every night, instead of only occasionally. The conclusion is, that she was not ordained to rule the night, seeing that, by a different arrangement, this could be more effectually accomplished. But with all his skill in celestial mechanics, Laplace would not, by the suggested arrangement, improve matters. If the moon' s orbit were situated where he proposed, her light would be sixteen times less than at present, and, what is more, the arrangement would not be a stable one. The moon would not only be at first a very dim lamp, but it would be in danger of going out altogether.
Sir David Brewster, in maintaining the habitableness of the moon, questions the doctrine that her use is to give light to the earth; and he does this on the ground that she would give a much better light if her surface was all of a chalky whiteness, and not studded over, as it is, with dark spots. Now, granting that there might be a happier arrangement, if the use of the moon was to give light—granting that it would be better to have a wider orbit, and a more uniform disc, are we to conclude that a use cannot be proved, unless we can shew that it is the best possible contrivance for the use intended? Let us take the case of Paley's watch on the heath. Would the inference of design be legitimate only on the supposition that the watch had the most faultless scapement, and the most artistic finish? Would not some rude, old crown-and-verge movement, dropped by some boor as he crossed the common, quite as irresistibly lead to the inference of design? And in dealing with the mechanism of the heavens, the real question at issue, is not—Is the intelligent contriver perfect? but. Is there a contriver at all? No doubt, the ultimate aim of the theist is to prove a perfect intelligence, but the first is to prove that there is an intelligence—that the use necessarily implies a designing mind, lie knows that the atheist must be forced to surrender all, if he admits that mind, in any form, is necessary to account for material laws and arrangements. When it is therefore held that the design of the moon is to give light, or the eye to see, it is not necessary at all to prove that the moon is the best possible lamp, or the eye the best possible lens.
But is the atheist to be permitted to maintain his position that any given arrangement is imperfect? Are we to concede to Laplace that he can improve the mechanism of the solar system? By no means. We may not be able to prove the absolute perfection of the arrangement, but we can shew the probability that the caviller is far more likely to be at fault, than that there should be a defect in the machine. A skilful mechanician may, on examining the works of a watch, say, without presumption, that the scapement is imperfect, and that he could suggest an improvement; and the reason simply is, that the tools formed by man for useful purposes have their object clearly defined. It is easy to see what the one requirement of a good scapement, for example, is, and there is no presumption in suggesting how this one well-defined object is to be attained in a more satisfactory manner. But the instruments of nature are not like human tools. The extent of their uses cannot be defined. All nature is one great whole; and it would require omniscience itself to say whether any given arrangement is the best possible for the innumerable uses it may subserve. To give light is one use of the moon, but we know not the many other uses it may serve. It is not, however, necessary to discover all these uses in order to maintain the position that it is ordained to give light, and we are not entitled to criticise its efficiency till we know all its functions.
Although we cannot prove the absolute perfection of any contrivance, yet, when increased research invariably discovers new points of excellence, we are warranted to conclude that, did we know all, we would be forced to acknowledge that all is perfect. We see only a few of the spokes of a revolving wheel, and it accords more with the modesty of true science, to ascribe the apparent imperfection to our point of view, than to conclude that the circle is defective. The more we enlarge our view the more complete does the circle become; and it is but the doctrine of inductive philosophy to conclude, that if our vision were entirely unobstructed, the machinery would appear in all its perfection. But Laplace and M. Comte would project their own imperfection on the perfect works of God.
To appreciate the usefulness of the moon as a source of light, we must view man in his least civilised state. The refinements of civilisation have, to a great degree, contracted the usefulness of the moon in this respect. City life, too, is not favourable to a grateful spirit for the service of the moon. In towns lighted by gas, little depends on the state of the moon; but in the country, the moon is consulted in the fixing of all social and religious meetings, and country people in general are able to inform you as to the quarter in which the moon is. This mixing up of the moon with the daily thoughts of the people in rural scenes, shews that her usefulness is fully appreciated.
In savage life, especially in high latitudes, the moon is an ever-present power. When the Red Indian speaks of moons, as measures of time, he speaks in the tone of affection and reverence for the benign luminary that guides his steps through the trackless forest. The Oriental bows to the sun, but the Red Indian nurtures his grand and impassive nature in the mild beams of the moon. In hunting and trapping, the moon is his ever- faithful ally, and he would as soon think of doubting its use, as he would the use of his spear or his traps.
But the use of the moon is not confined to lightgiving. As a mechanical power, the moon is of, much service. The sun is the grand source of power on the face of the earth, but still, some little work is left to the moon. To her chiefly is assigned the task of raising the tides of the ocean. The tides are of incalculable benefit to man. In a sanitary point of view, the moon may be regarded as the great scavenger of our globe. Twice every day she flushes, with sea water in abundance, the rivers on which our towns are situated, and keeps them comparatively pure. Again, by her mechanical power, she bears ships on the crest of the tidal wave, deep into the heart of the country, where the centres of commerce are often found. Insignificant streams are thus rendered navigable, and cities brought into immediate connexion with the ocean—the highway of commerce. By the convenience afforded by the moon, London is, at the same time, connected with the ocean, and in the heart of the country, where it can be best protected from any invasion. In an island of such limited extent as Great Britain, the rivers must necessarily be small, but the tidal wave compensates for the defect, and gives us the advantages of river navigation. The mechanical power of the tide is made available by means of the tide mill. The rise and fall of the tide can be utilised as well as the fall of a river. This source of power has not been very generally turned to account, though there is no mechanical difficulty in applying it.
One of the most useful purposes served by the moon is that of a time-ball. When the time-ball falls at Greenwich, all within range of seeing, have the opportunity of knowing that it is precisely one o'clock at Greenwich. But its utility would be vastly increased, if the mariner far out at sea, could also see the signal, for it would at once give him his longitude. He has the means on shipboard, of ascertaining the local time, and at sea the clock in the saloon is put right every day at noon. If the ship is sailing westwards, the hands must be put back in proportion to the speed of the ship. The longitude of a ship is simply the difference between her own clock and a clock at Greenwich. If, for example, the ship's clock shews twelve o'clock at the moment the time-ball falls at one o'clock at Greenwich, her longitude is one hour west. The great object, then, is to see the time-ball at Greenwich, or something equivalent to it. The moon admirably serves the purpose. Suppose it is previously ascertained, by calculationjthat the moment the ball falls, the moon, in its progress through the sky, will touch or occult a certain star; then, though the mariner cannot see the ball, it is enough if he can watch the moment when the moon comes in contact with the star. The nautical almanac tells when he may expect the contact, and if he succeeds in observing it, it is as serviceable to him as if he had the time-signal itself. It is not necessary, however, that the moon should actually come in contact with some star. It may happen that the moon is still some little distance from the star at the moment the ball falls, but this serves the purpose equally. If it is known from the almanac, that the moon will be so many degrees from the star when the ball falls, it is only necessary to watch the instant when the moon comes within the precise distance, in order to know when it is one o'clock at Greenwich. But there is no need to limit the signal to one o'clock. It is only necessary to know from the almanac the time by the Greenwich clock when the moon will arrive at any point i'n her track across the heavens, in order to ascertain what the time at Greenwich is. To people living along a line of railway, the trains are so many time-signals. The time-table shews the Greenwich time when the trains should arrive at each station, and if they be regular, they serve the purpose of a clock. If a person wishes to know the longitude of the station, he has only to ascertain the local time from a sun-dial, and the difference between this and the railway time gives the longitude. What the railway train is to the landsman, the moon is to the mariner, and while the landsman uses a dial to ascertain the local time, the sailor uses a sextant. The sailor may adopt the obvious plan of carrying a chronometer set to Greenwich time, and which, by comparison with the local time, at once gives him the longitude; but no chronometer can equal the moon as an indicator of time. The captain may forget to wind up the chronometer, some parts of the works may give way, the rate of going may change, and many other accidents may occur to render the chronometer useless; but the moon can ever be relied on. No winding up is needed, no danger of the mainspring of gravitation breaking. She no doubt changes her rate of motion, but the rate of change can be calculated so that her precise position at any moment can be predicted with absolute accuracy.
The moon would be useful to man for the division of time, though it was only monthly periods that she marked off, and though she only met the necessities of savage life; but the usefulness becomes more apparent when she serves to give the minutest divisions of time to meet the increasing necessities of man as he advances in civilisation. It is this development of adaptation, running parallel with the development of the human intellect and the social advance of the human race, that most clearly indicates the exercise of divine intelligence. No doubt the illustrations of direct adaptation of the material world to man's physical constitution are striking enough, and it is these that are usually appealed to in support of a divine intelligence; but the secondary adaptations to man as a moral, intellectual, and social being, are still more striking and convincing. These adaptations, being progressive, also recognise the progressive nature of man and his higher destiny.
It may appear straining the argument too much to speak of the usefulness of the moon in developing poetical sentiment, but we have an æsthetic element in our nature which requires suitable appliances, as much as the functions of digestion and respiration. The material universe, in the midst of which we are placed, is not adapted merely to gross utilitarian purposes. It is equally fitted to cherish refined and lofty sentiment, and when a want of our nature is supplied we have a use. And how useful in this respect is the moon! Volumes might be filled with the poetry of the moon; and yet the theme is ever fresh. The poet and the painter find the subject to be inexhaustible. The aspect of nature in moonlight is so different, that we have, by the gift of the lesser light, virtually two worlds for our abode. The gorgeous sunlit scene gives way, like a dissolving view, to the milder radiance of the moon, and, as by a magic spell, a new scene, with its own characteristic beauty, starts out from nature's canvas. The picturesque effects of moonlight are infinitely varied; but how many are lost simply because we do not look for them with aesthetic fondness. In crossing the Atlantic, we had once the opportunity of witnessing the effect produced by a moon picture which was new to the whole ship's company, and to which we do not remember any allusion in the pages of the poet or the savant. The attention of the captain was called to a dark pillar rising from the horizon and terminating in the full moon, which was about thirty degrees above the horizon. It assumed the form of an elongated pyramid, the moon being at the apex. He had, no doubt, seen this hundreds of times before, but he had never really observed it. But now that his attention was called to it, he was filled with wonder at the magnificence of the phenomenon, and the distinct manner in which the pillar stood out in relief from the sky. The officers gathered round the captain, and it was also new to them, as they gazed in admiration. The passengers, who lingered on the deck, swelled the crowd of admirers, and to all the spectacle was perfectly novel. After all were filled with the beauty of the spectacle, the spirit of philosophy arose, and the captain was appealed to for an explanation. His solution was one characteristic of the sailor—it was a sign of bad weather. This tentative effort at a theory was negatived by simply shading the eye from the bright wake of the moon in the sea. The instant this was done, the majestic pillar vanished, shewing that it was the counterpart of the wake, and merely the effect of contrast. This simple solution did not divest the object of its beauty, and during successive nights the same effect was watched with increased interest, and all tacitly acknowledged that the moon had a use in thus giving a new charm to the ocean scenery, and helping to while away the hours of the long voyage.
The moon has a use, too, in reference to the religious element in man's nature, not merely by furnishing an argument for design but by directly cherishing the religious spirit. Its adaptation to this purpose is shewn in the almost universal adoration paid to this luminary. The idolatry of the heathen is only the perversion of a native instinct of the human heart, and is a testimony to the fact that the object of adoration has a natural tendency, in the pure and enlightened spirit, to lift the heart up to God. When the Psalmist considered the heavens, and contemplated the luminaries in detail, the moon had the first place, as declaring the glory and goodness of God. The moon is the most familiar symbol of God's providence; we feel that she is nearer to us than any other heavenly body, and that her special duty is to wait upon us. She accompanies us like a guardian angel, bearing a lamp before us, in the darkness of the night. She circles round us like the parent bird round the nest of her helpless young. She is the first round in the ladder that leads up to the throne of God — the first link in the chain that binds us to the universe of worlds. The moon is thus specially fitted to be useful in bringing home to us the presence and the providence of God.
It was undoubtedly the feeling that the moon was our nearest neighbour, that led man to ascribe fanciful functions to the moon. While the sun was supposed to preside over the heart, the moon was believed to have supreme power in controlling the brain—the characteristic part of man's organisation. Hence, any crisis in mental phenomena was always connected with the phases of the moon, and paroxysms of insanity were long believed to be regulated by the maxima and minima of the moon's illuminated disc. It is strange that such a delusion should have so long clung to the human mind although contradicted by innumerable facts. This is explained by the principle of an anterior bias, and the love of coincidences. The passion of tracing coincidence has its use in prompting to scientific inquiry, but we often find it indulged in for its own sake. How many examine their barometer daily to see whether it is rising or falling, simply for the pleasure of marking the coincidence between the weather and the indications of the barometer. They may be neither mariners nor sailors, and have no immediate interests at stake. They may have no pretensions to scientific inquiry. And whether their theory is that the barometer influences the weather, or the weather the barometer, the pleasure is still great of tracing a coincidence. So, in regard to the moon, the human mind has derived great pleasure in tracing the coincidence between the moon's phases and the mental and physical phenomena on the surface of the globe. From the bias of this love of coincidence, the many adverse facts were overlooked, and the few favourable ones were allowed to have more than their due weight. The influence of the moon in insanity is now entirely discredited, but many cling to its influence on the weather. Many who have a half conviction that their belief is a mere superstition, still have a pleasure in speaking of a change of weather at the new or full moon. And there are always a sufficient number of coincidences to give colour to their belief. Almost every different country has its own rules for prognosticating the weather from the phases of the moon, but however different they may be, they all serve equally well to cherish the conviction that there is some real influence. Many scientific researches have been made to settle the point, but no decisive result has been arrived at. Sometimes a preponderating effect has been ascribed to particular phases, but it has been as often against the popular belief as in favour of it.
There is no a priori reason why the moon should not influence the weather. It is simply a question of fact, and as yet no appreciable effect has been detected. Perhaps the only effect for which there is tolerable probability, is the influence of the full moon in dispelling light fleecy clouds. This is effected by the heat of the moon which is expended in the higher strata of the air—the heat being employed in converting the clouds into invisible vapour.
While science is lessening the influence of the moon in one direction, it is extending it in another. The moon is now found to be a magnet, and to exercise an influence on the magnetic elements of our globe. The oscillations of the barometer are found to be slightly affected by the phases of the moon. The rays of the moon are found to have a chemical influence like those of the sun, and its heat, though insignificant, has at last been measured. These physical effects render it not improbable that the moon may influence the weather and the human constitution, but the precise effects are yet to be discerned. The effects hitherto ascribed to the moon have been shewn to be either fanciful, or, when real, produced by other causes. But admitting all this, there is a wide enough margin for the undoubted uses of the moon.