Myths and Marvels of Astronomy

by Richard A. Proctor

'"And," continued Sir John, "why cannot the illuminating microscope, say the hydro-oxygen, be applied to render distinct, and, if necessary, even to magnify, the focal object?" Sir David sprung from his chair' [and well he might, though not] 'in an ecstasy of conviction, and, leaping half-way to the ceiling, exclaimed, "Thou art the man!" Each philosopher anticipated the other in presenting the prompt illustration that if the rays of the hydro-oxygen microscope, passed through a drop of water containing the larvæ of a gnat and other objects invisible to the naked eye, rendered them not only keenly but firmly magnified to dimensions of many feet; so could the same artificial light, passed through the faintest focal object of a telescope, both distinctify (to coin a new word for an extraordinary occasion) and magnify its feeblest component members. The only apparent desideratum was a recipient for the focal image which should transfer it, without refranging it, to the surface on which it was to be viewed under the revivifying light of the microscopic reflectors.'

Singularly enough, the idea here mentioned does not appear to many so absurd as it is in reality. It is known that the image formed by the large lens of an ordinary telescope or the large mirror of a reflecting telescope is a real image; not a merely virtual image like that which is seen in a looking-glass. It can be received on a sheet of paper or other white surface just as the image of surrounding objects can be thrown upon the white table of the camera obscura. It is this real image, in fact, which we look at in using a telescope of any sort, the portion of such a telescope nearest to the eye being in reality a microscope for viewing the image formed by the great lens or mirror, as the case may be. And it does not seem to some altogether absurd to speak of illuminating this image by transfused light, or of casting by means of an illuminating microscope a vastly enlarged picture of this image upon a screen. But of course the image being simply formed by the passage of rays (which originally came from the object whose image they form) through a certain small space, to send other rays (coming from some other luminous object) through the same small space, is not to improve, but, so far as any effect is produced at all, to impair, the distinctness of the image. In fact, if these illuminating rays reached the eye, they would seriously impair the distinctness of the image. Their effect may be compared exactly with the effect of rays of light cast upon the image in a camera obscura; and, to see what the effect of such rays would be, we need only consider why it is that the camera is made 'obscura,' or dark. The effect of the transfusion of light through a telescopic image may be easily tried by any one who cares to make the experiment. He has only to do away with the tube of his telescope (substituting two or three straight rods to hold the glass in its place), and then in the blaze of a strong sun to direct the telescope on some object lying nearly towards the sun. Or if he prefer artificial light for the experiment, then at night let him direct the telescope so prepared upon the moon, while a strong electric light is directed upon the place where the focal image is formed (close in front of the eye). The experiment will not suggest very sanguine hopes of good result from the transfusion of artificial light. Yet, to my own knowledge, not a few who were perfectly well aware that the lunar hoax was not based on facts, have gravely reasoned that the principle suggested might be sound, and, in fact, that they could see no reason why astronomers should not try it, even though it had been first suggested as a joke.

To return, however, to the narrative. 'The co-operative philosophers, having hit upon their method, determined to test it practically. They decided that a medium of the purest plate-glass (which it is said they obtained, by consent, be it observed, from the shop-window of M. Desanges, the jeweller to his ex-majesty Charles X., in High Street) was the most eligible they could discover. It answered perfectly with a telescope which magnified a hundred times, and a microscope of about thrice that power.' Thus fortified by experiment, and 'fully sanctioned by the high optical authority of Sir David Brewster, Sir John laid his plan before the Royal Society, and particularly directed to it the attention of his Royal Highness the Duke of Sussex, the ever munificent patron of science and the arts. It was immediately and enthusiastically approved by the committee chosen to investigate it, and the chairman, who was the Royal President' (this continual reference to royalty is manifestly intended to give a British tone to the narrative), 'subscribed his name for a contribution of £10,000, with a promise that he would zealously submit the proposed instrument as a fit object for the patronage of the privy purse. He did so without delay; and his Majesty, on being informed that the estimated expense was £70,000, naïvely enquired if the costly instrument would conduce to any improvement in navigation. On being informed that it undoubtly would, the sailor king promised a carte blanche for any amount which might be required.'

All this is very clever. The 'sailor king' comes in as effectively to give vraisemblance to the narrative as 'Crabtree's little bronze Shakspeare that stood over the fireplace,' and the 'postman just come to the door with a double letter from Northamptonshire.'

Then comes a description of the construction of the object-glass, twenty-four feet in diameter, 'just six times the size of the elder Herschel's;' who, by the way, never made a telescope with an object-glass. The account of Sir John Herschel's journey from England, and even some details of the construction of the observatory, were based on facts, indeed, so many persons in America as well as in England were acquainted with some of these circumstances, that it was essential to follow the facts as closely as possible. Of course, also, some explanation had to be given of the circumstance that nothing had before been heard respecting the gigantic instrument taken out by Sir John Herschel. 'Whether,' says the story, 'the British Government were sceptical concerning the promised splendour of the discoveries, or wished them to be scrupulously veiled until they had accumulated a full-orbed glory for the nation and reign in which they originated, is a question which we can only conjecturally solve. But certain it is that the astronomer's royal patrons enjoined a masonic taciturnity upon him and his friends until he should have officially communicated the results of his great experiment.'

It was not till the night of January 10, 1835, that the mighty telescope was at length directed towards our satellite. The part of the moon selected was on the eastern part of her disc. 'The whole immense power of the telescope was applied, and to its focal image about one half of the power of the microscope. On removing the screen of the latter, the field of view was covered throughout its entire area with a beautifully distinct and even vivid representation of basaltic rock. Its colour was a greenish brown; and the width of the columns, as defined by their interstices on the canvas, was invariably twenty-eight inches. No fracture whatever appeared in the mass first presented; but in a few seconds a shelving pile appeared, of five or six columns' width, which showed their figure to be hexagonal, and their articulations similar to those of the basaltic formation at Staffa. This precipitous cliff was profusely covered with a dark red flower, precisely similar, says Dr. Grant, to the Papaver Rhœus, or Rose Poppy, of our sublunary cornfields; and this was the first organic production of nature in a foreign world ever revealed to the eyes of men.'

It would be wearisome to go through the whole series of observations thus fabled, and only a few of the more striking features need be indicated. The discoveries are carefully graduated in interest. Thus we have seen how, after recognising basaltic formations, the observers discovered flowers: they next see a lunar forest, whose 'trees were of one unvaried kind, and unlike any on earth except the largest kind of yews in the English churchyards.' (There is an American ring in this sentence, by the way, as there is in one, a few lines farther on, where the narrator having stated that by mistake the observers had the Sea of Clouds instead of a more easterly spot in the field of view, proceeds to say: 'However, the moon was a free country, and we not as yet attached to any particular province.') Next a lunar ocean is described, 'the water nearly as blue as that of the deep sea, and breaking in large white billows upon the strand, while the action of very high tides was quite manifest upon the face of the cliffs for more than a hundred miles.' After a description of several valleys, hills, mountains and forests, we come to the discovery of animal life. An oval valley surrounded by hills, red as the purest vermilion, is selected as the scene. 'Small collections of trees, of every imaginable kind, were scattered about the whole of this luxuriant area; and here our magnifiers blessed our panting hopes with specimens of conscious existence. In the shade of the woods we beheld brown quadrupeds having all the external characteristics of the bison, but more diminutive than any species of the bos genus in our natural history.' Then herds of agile creatures like antelopes are described, 'abounding on the acclivitous glades of the woods.' In the contemplation of these sprightly animals the narrator becomes quite lively. 'This beautiful creature,' says he, 'afforded us the most exquisite amusement. The mimicry of its movements upon our white painted canvas was as faithful and luminous as that of animals within a few yards of the camera obscura. Frequently, when attempting to put our fingers upon its beard, it would suddenly bound away as if conscious of our earthly impertinence; but then others would appear, whom we could not prevent nibbling the herbage, say or do to them what we would.'

A strange amphibious creature, of a spherical form, rolling with great velocity along a pebbly beach, is the next object of interest, but is presently lost sight of in a strong current setting off from the angle of an island. After this there are three or four pages descriptive of various lunar scenes and animals, the latter showing a tendency, singular considering the circumstances, though very convenient for the narrator, to become higher and higher in type as the discoveries proceed, until an animal somewhat of the nature of the missing link is discovered. It is found in the Endymion (a circular walled plain) in company with a small kind of reindeer, the elk, the moose, and the horned bear, and is described as the biped beaver. It 'resembles the beaver of the earth in every other respect than in its destitution of a tail, and its invariable habit of walking upon only two feet. It carries its young in its arms like a human being, and moves with an easy gliding motion. Its huts are constructed better and higher than those of many tribes of human savages, and, from the appearance of smoke in nearly all of them, there is no doubt of its being acquainted with the use of fire. Still, its head and body differ only in the points stated from that of the beaver; and it was never seen except on the borders of lakes and rivers, in which it has been observed to immerse for a period of several seconds.'

The next step towards the climax brings us to domestic animals, 'good large sheep, which would not have disgraced the farms of Leicestershire or the shambles of Leadenhall Market; we fairly laughed at the recognition of so familiar an acquaintance in so distant a land. Presently they appeared in great numbers, and, on reducing the lenses, we found them in flocks over a great part of the valley. I need not say how desirous we were of finding shepherds to these flocks, and even a man with blue apron and rolled-up sleeves would have been a welcome sight to us, if not to the sheep; but they fed in peace, lords of their own pastures, without either protector or destroyer in human shape.'

In the meantime, discussion had arisen as to the lunar locality where men, or creatures resembling them, would most likely be found. Herschel had a theory on the subject—viz., that just where the balancing or libratory swing of the moon brings into view the greatest extent beyond the eastern or western parts of that hemisphere which is turned earthwards in the moon's mean or average position, lunar inhabitants would probably be found, and nowhere else. This, by the way (speaking seriously), is a rather curious anticipation of a view long subsequently advanced by Hansen, and for a time adopted by Sir J. Herschel, that possibly the remote hemisphere of the moon may be a fit abode for living creatures, the oceans and atmosphere which are wanting on the nearer hemisphere having been (on this hypothesis) drawn over to the remoter because of a displacement of the moon's centre of gravity. I ventured in one of my first books on astronomy to indicate objections to this theory, the force of which Sir J. Herschel admitted in a letter addressed to me on the subject.