But was nothing to be gained by the trip? Though missing actual contact with the Moon, might they not pass near enough to solve several problems in physics and geology over which scientists had been for a long time puzzling their brains in vain? Even this would be some compensation for all their trouble, courage, and intelligence. As to what was to be their own fate, to what doom were themselves to be reserved—they never appeared to think of such a thing. They knew very well that in the midst of those infinite solitudes they should soon find themselves without air. The slight supply that kept them from smothering could not possibly last more than five or six days longer. Five or six days! What of that? Quand même! as Ardan often exclaimed. Five or six days were centuries to our bold adventurers! At present every second was a year in events, and infinitely too precious to be squandered away in mere preparations for possible contingencies. The Moon could never be reached, but was it not possible that her surface could be carefully observed? This they set themselves at once to find out.
The distance now separating them from our Satellite they estimated at about 400 miles. Therefore relatively to their power of discovering the details of her disc, they were still farther off from the Moon than some of our modern astronomers are to-day, when provided with their powerful telescopes.
We know, for example, that Lord Rosse's great telescope at Parsonstown, possessing a power of magnifying 6000 times, brings the Moon to within 40 miles of us; not to speak of Barbican's great telescope on the summit of Long's Peak, by which the Moon, magnified 48,000 times, was brought within 5 miles of the Earth, where it therefore could reveal with sufficient distinctness every object above 40 feet in diameter.
Therefore our adventurers, though at such a comparatively small distance, could not make out the topographical details of the Moon with any satisfaction by their unaided vision. The eye indeed could easily enough catch the rugged outline of these vast depressions improperly called "Seas," but it could do very little more. Its powers of adjustability seemed to fail before the strange and bewildering scene. The prominence of the mountains vanished, not only through the foreshortening, but also in the dazzling radiation produced by the direct reflection of the solar rays. After a short time therefore, completely foiled by the blinding glare, the eye turned itself unwillingly away, as if from a furnace of molten silver.
The spherical surface, however, had long since begun to reveal its convexity. The Moon was gradually assuming the appearance of a gigantic egg with the smaller end turned towards the Earth. In the earlier days of her formation, while still in a state of mobility, she had been probably a perfect sphere in shape, but, under the influence of terrestrial gravity operating for uncounted ages, she was drawn at last so much towards the centre of attraction as to resemble somewhat a prolate spheriod. By becoming a satellite, she had lost the native perfect regularity of her outline; her centre of gravity had shifted from her real centre; and as a result of this arrangement, some scientists have drawn the conclusion that the Moon's air and water have been attracted to that portion of her surface which is always invisible to the inhabitants of the Earth.
The convexity of her outline, this bulging prominence of her surface, however, did not last long. The travellers were getting too near to notice it. They were beginning to survey the Moon as balloonists survey the Earth. The Projectile was now moving with great rapidity—with nothing like its initial velocity, but still eight or nine times faster than an express train. Its line of movement, however, being oblique instead of direct, was so deceptive as to induce Ardan to flatter himself that they might still reach the lunar surface. He could never persuade himself to believe that they should get so near their aim and still miss it. No; nothing might, could, would or should induce him to believe it, he repeated again and again. But Barbican's pitiless logic left him no reply.
"No, dear friend, no. We can reach the Moon only by a fall, and we don't fall. Centripetal force keeps us at least for a while under the lunar influence, but centrifugal force drives us away irresistibly."
These words were uttered in a tone that killed Ardan's last and fondest hope.
* * * * *
The portion of the Moon they were now approaching was her northern hemisphere, found usually in the lower part of lunar maps. The lens of a telescope, as is well known, gives only the inverted image of the object; therefore, when an upright image is required, an additional glass must be used. But as every additional glass is an additional obstruction to the light, the object glass of a Lunar telescope is employed without a corrector; light is thereby saved, and in viewing the Moon, as in viewing a map, it evidently makes very little difference whether we see her inverted or not. Maps of the Moon therefore, being drawn from the image formed by the telescope, show the north in the lower part, and vice versa. Of this kind was the Mappa Selenographica, by Beer and Maedler, so often previously alluded to and now carefully consulted by Barbican. The northern hemisphere, towards which they were now rapidly approaching, presented a strong contrast with the southern, by its vast plains and great depressions, checkered here and there by very remarkable isolated mountains.
At midnight the Moon was full. This was the precise moment at which the travellers would have landed had not that unlucky bolide drawn them off the track. The Moon was therefore strictly up to time, arriving at the instant rigidly determined by the Cambridge Observatory. She occupied the exact point, to a mathematical nicety, where our 28th parallel crossed the perigee. An observer posted in the bottom of the Columbiad at Stony Hill, would have found himself at this moment precisely under the Moon. The axis of the enormous gun, continued upwards vertically, would have struck the orb of night exactly in her centre.
It is hardly necessary to tell our readers that, during this memorable night of the 5th and 6th of December, the travellers had no desire to close their eyes. Could they do so, even if they had desired? No! All their faculties, thoughts, and desires, were concentrated in one single word: "Look!" Representatives of the Earth, and of all humanity past and present, they felt that it was with their eyes that the race of man contemplated the lunar regions and penetrated the secrets of our satellite! A certain indescribable emotion therefore, combined with an undefined sense of responsibility, held possession of their hearts, as they moved silently from window to window.
Their observations, recorded by Barbican, were vigorously remade, revised, and re-determined, by the others. To make them, they had telescopes which they now began to employ with great advantage. To regulate and investigate them, they had the best maps of the day.
Whilst occupied in this silent work, they could not help throwing a short retrospective glance on the former Observers of the Moon.
The first of these was Galileo. His slight telescope magnified only thirty times, still, in the spots flecking the lunar surface, like the eyes checkering a peacock's tail, he was the first to discover mountains and even to measure their heights. These, considering the difficulties under which he labored, were wonderfully accurate, but unfortunately he made no map embodying his observations.
A few years afterwards, Hevel of Dantzic, (1611-1688) a Polish astronomer—more generally known as Hevelius, his works being all written in Latin—undertook to correct Galileo's measurements. But as his method could be strictly accurate only twice a month—the periods of the first and second quadratures—his rectifications could be hardly called successful.
Still it is to the labors of this eminent astronomer, carried on uninterruptedly for fifty years in his own observatory, that we owe the first map of the Moon. It was published in 1647 under the name of Selenographia. He represented the circular mountains by open spots somewhat round in shape, and by shaded figures he indicated the vast plains, or, as he called them, the seas, that occupied so much of her surface. These he designated by names taken from our Earth. His map shows you a Mount Sinai the midst of an Arabia, an Ætna in the centre of a Sicily, Alps, Apennines, Carpathians, a Mediterranean, a Palus Mæolis, a Pontus Euxinus, and a Caspian Sea. But these names seem to have been given capriciously and at random, for they never recall any resemblance existing between themselves and their namesakes on our globe. In the wide open spot, for instance, connected on the south with vast continents and terminating in a point, it would be no easy matter