Across the Zodiac / The Story of a Wrecked Record

by Percy Greg

I mean that, apart from the polar compression, the shape seemed as if the spheroid were irregularly squeezed; so that though not broken by projection or indentation, the limb did not present the regular quasi-circular curvature exhibited in the focus of our telescopes. Also, between the inner ring and the planet, with a power of 500, I discerned what appeared to be a dark purplish ring, semi-transparent, so that through it the bright surface of Saturn might be discerned as through a veil. Mercury shone brightly several degrees outside the halo surrounding the Earth's black disc; and Venus was also visible; but in neither case did my observations allow me to ascertain anything that has not been already noted by astronomers. The dim form of Uranus was better defined than I had previously seen it, but no marking of any kind was perceptible.

Rising from my second, or, so to speak, midday rest, and having busied myself for some little time with what I may call my household and garden duties, I observed the discometer at 1h. (or 5 P.M.). It indicated about two hundred terrestrial radii of elevation. I had, of course, from the first been falling slightly behind the Earth in her orbital motion, and was no longer exactly in opposition; that is to say, a line drawn from the Astronaut to the Earth's centre was no longer a prolongation of that joining the centres of the Earth and Sun. The effect of this divergence was now perceptible. The earthly corona was unequal in width, and to the westward was very distinctly brightened, while on the other side it was narrow and comparatively faint. While watching this phenomenon through the lower lens, I thought that I could perceive behind or through the widest portion of the halo a white light, which at first I mistook for one of those scintillations that had of late become scarcely discernible. But after a time it extended visibly beyond the boundary of the halo itself, and I perceived that the edge of the Sun's disc had come at last into view. It was but a minute and narrow crescent, but was well worth watching. The brightening and broadening of the halo at this point I perceived to be due, not to the Sun's effect upon the atmosphere that produced it, but chiefly to the twilight now brightening on that limb of the Earth's disc; or rather to the fact that a small portion of that part of the Earth's surface, where, if the Sun were not visible, he was but a very little below the horizon, had been turned towards me. I saw through the telescope first a tiny solar crescent of intense brightness, then the halo proper, now exceedingly narrow, and then what looked like a silver terrestrial crescent, but a mere thread, finer and shorter than any that the Moon ever displays even to telescopic observers on Earth; since, when such a minute portion of her illuminated surface is turned towards the Earth, it is utterly extinguished to our eyes by the immediate vicinity of the Sun, as was soon the case with the terrestrial crescent in question. I watched long and with intense interest the gradual change, but I was called away from it by a consideration of no little practical moment. I must now be moving at a rate of nearly, if not quite, 40,000 miles an hour, or about a million miles per diem. It was not my intention, for reasons I shall presently explain, ever greatly to exceed this rate; and if I meant to limit myself to a fixed rate of speed, it was time to diminish the force of the apergic current, as otherwise before its reduction could take effect I should have attained an impulse greater than I desired, and which could not be conveniently or easily diminished when once reached. Quitting, therefore, though reluctantly, my observation of the phenomena below me, I turned to the apergion, and was occupied for some two or three hours in gradually reducing the force as measured by the cratometer attached to the downward conductor, and measuring with extreme care the very minute effect produced upon the barycrite and the discometer. Even the difference between 200 and 201 radii of elevation or apogaic distance was not easily perceptible on either. It took, of course, much more minute observation and a much longer time to test the effect produced by the regulation of the movement, since whether I traveller forty, forty-five, or forty-two thousand miles in the course of one hour made scarcely any difference in the diameter of the Earth's disc, still less, for reasons above given, in the gravity. By midnight, however, I was satisfied that I had not attained quite 1,000,000 miles, or 275 terrestrial radii; also that my speed was not greater than 45,000 miles (11¼ radii) per hour, and was not, I thought, increasing. Of this last point, however, I could better satisfy myself at the end of my four hours' rest, to which I now betook myself.

I woke about 4h. 30m., and on a scrutiny of the instruments, felt satisfied that I was not far out in my calculations. A later hour, however, would afford a more absolute certainty. I was about to turn again to the interesting work of observation through the lens in the floor, when my attention was diverted by the sight of something like a whitish cloud visible through the upper window on my left hand. Examined by the telescope, its widest diameter might be at most ten degrees. It was faintly luminous, presenting an appearance very closely resembling that of a star cluster or nebula just beyond the power of resolution. As in many nebulae, there was a visible concentration in one part; but this did not occupy the centre, but a position more resembling that of the nucleus of a small tailless comet. The cloudlet might be a distant comet, it might be a less distant body of meteors clustering densely in some particular part of their orbit; and, unfortunately, I was not likely to solve the problem. Gradually the nebula changed its position, but not its form, seeming to move downwards and towards the stern of my vessel, as if I were passing it without approaching nearer. By the time that I was satisfied of this, hunger and even faintness warned me that I must not delay preparing my breakfast. When I had finished this meal and fulfilled some necessary tasks, practical and arithmetical, the hand of the chronometer indicated the eighth hour of my third day. I turned again somewhat eagerly to the discometer, which showed an apparent distance of 360 terrestrial radii, and consequently a movement which had not materially varied from the rate of 11¼ radii per hour. By this time the diameter of the Earth was not larger in appearance than about 19', less than two-thirds that of the Sun; and she consequently appeared as a black disc covering somewhat more than one-third of his entire surface, but by no means concentrical. The halo had of course completely disappeared; but with the vernier it was possible to discern a narrow band or line of hazy grey around the black limb of the planet. She was moving, as seen from the Astronaut, very slightly to the north, and more decidedly, though very slowly, to the eastward; the one motion due to my deliberately chosen direction in space, the other to the fact that as my orbit enlarged I was falling, though as yet slowly, behind her. The sun now shone through, the various windows, and, reflected from the walls, maintained a continuous daylight within the Astronaut, as well diffused as by the atmosphere of Earth, strangely contrasting the star-spangled darkness outside.

At the beginning as at the end of my voyage, I steered a distinct course, governed by considerations quite different from those which controlled the main direction of my voyage. Thus far I had simply risen straight from the Earth in a direction somewhat to the southward, but on the whole "in opposition," or right away from the Sun. So, at the conclusion of my journey, I should have to devote some days to a gradual descent upon Mars, exactly reversing the process of my ascent from the Earth. But between these two periods I had comparatively little to do with either planet, my course being governed by the Sun, and its direction and rate being uniform. I wished to reach Mars at the moment of opposition, and during the whole of the journey to keep the Earth between myself and the Sun, for a reason which may not at first be obvious. The moment of opposition is not necessarily that at which Mars is nearest to the Earth, but is sufficiently so for practical calculation. At that moment, according to the received measurement of planetary distances, the two would be more than 40 millions of miles apart. In the meantime the Earth, travelling on an interior or smaller orbit, and also at a greater absolute speed, was gaining on Mars. The Astronaut, moving at the Earth's rate under an impulse derived from the Earth's revolution round the Sun (that due to her rotation on her own axis having been got rid of, as aforesaid), traveller in an orbit constantly widening, so that, while gaining on Mars, I gained on him less than did the Earth, and was falling behind her. Had I used the apergy only to drive me directly outward from the Sun, I should move under the impulse derived from the Earth about 1,600,000 miles a day, or 72 millions of miles in forty-five days, in the direction common to the two planets. The effect of the constantly widening orbit would be much as if the whole motion took place on one midway between those of the Earth and Mars, say 120 millions of miles from the Sun. The arc described on this orbit would be equivalent to 86 millions of miles on that of Mars. The entire arc of his orbit between the point opposite to that occupied by the Earth when I started and the point of opposition—the entire distance I had to gain as measured along his path—was about 116 millions of miles; so that, trusting to the terrestrial impulse alone, I should be some 30 millions behindhand at the critical moment. The apergic force must make up for this loss of ground, while driving me in a direction, so to speak, at right angles with that of the orbit, or along its radius, straight outward from the Sun, forty odd millions of miles in the same time. If I succeeded in this, I should reach the orbit of Mars at the point and at the moment of opposition, and should attain Mars himself. But in this I might fail, and I should then find myself under the sole influence of the Sun's attraction; able indeed to resist it, able gradually to steer in any direction away from it, but hardly able to overtake a planet that should lie far out of my line of advance or retreat, while moving at full speed away from me. In order to secure a chance of retreat, it was desirable as long as possible to keep the Earth between the Astronaut and the Sun; while steering for that point in space where Mars would lie at the moment when, as seen from the centre of the Earth, he would be most nearly opposite the Sun,—would cross the meridian at midnight. It was by these considerations that the course I henceforward steered was determined. By a very simple calculation, based on the familiar principle of the parallelogram of forces, I gave to the apergic current a force and direction equivalent to a daily motion of about 750,000 miles in the orbital, and rather more than a million in the radial line. I need hardly observe that it would not be to the apergic current alone, but to a combination of that current with the orbital impulse received at first from the Earth, that my progress and course would be due. The latter was the stronger influence; the former only was under my control, but it would suffice to determine, as I might from time to time desire, the resultant of the combination. The only obvious risk of failure lay in the chance that, my calculations failing or being upset, I might reach the desired point too soon or too late. In either case, I should be dangerously far from Mars, beyond his orbit or within it, at the time when I should come into a line with him and the Sun; or, again, putting the same mischance in another form, behind him or before him when I attained his orbit. But I trusted to daily observation of his position, and verification of my "dead reckoning" thereby, to find out any such danger in time to avert it.

The displacement of the Earth on the Sun's face proved it to be necessary that the apergic current should be directed against the latter in order to govern my course as I desired, and to recover the ground I had lost in respect to the orbital motion. I hoped for a moment that this change in the action of the force would settle a problem we had never been able to determine. Our experiments proved that apergy acts in a straight line when once collected in and directed along a conductor, and does not radiate, like other forces, from a centre in all directions. It is of course this radiation— diffusing the effect of light, heat, or gravity over the surface of a sphere, which surface is proportionate to the square of the radius—that causes these forces to operate with an energy inversely proportionate, not to the distance, but to its square. We had no reason to think that apergy, exempt as it is from this law, would be at all diminished by distance; and this view the rate of acceleration as I rose from the Earth had confirmed, and my entire experience has satisfied me that it is correct. None of our experiments, however, had indicated, or could well indicate, at what rate this force can travel through space; nor had I yet obtained any light upon this point. From the very first the current had been continuous, the only interruption taking place when I was not five hundred miles from the Earth's surface. Over so small a distance as that, the force would move so instantaneously that no trace of the interruption would be perceptible in the motion of the Astronaut. Even now the total interruption of the action of apergy for a considerable time would not affect the rate at which I was already moving. It was possible, however, that if the current had been hitherto wholly intercepted by the Earth, it might take so long a time in reaching the Sun that the interval between the movement of the helm and the response of the Astronaut's course thereto might afford some indication of the time occupied by the current in traversing the 96½ millions of miles which parted me from the Sun. My hope, however, was wholly disappointed. I could neither be sure that the action was instantaneous, nor that it was otherwise.

At the close of the third day I had gained, as was indicated by the instruments, something more than two millions of miles in a direct line from the Sun; and for the future I might, and did, reckon on a steady progress of about one and a quarter million miles daily under the apergic force alone—a gain in a line directly outward from the Sun of about one million. Henceforward I shall not record my observations, except where they implied an unexpected or altered result.

On the sixth day, I perceived another nebula, and on this occasion in a more promising direction. It appeared, from its gradual movement, to lie almost exactly in my course, so that if it were what I suspected, and were not at any great distance from me, I must pass either near or through it, and it would surely explain what had perplexed and baffled me in the case of the former nebula. At this distance the nature of the cloudlet was imperceptible to the naked eye. The window telescope was not adjustable to an object which I could not bring conveniently within the field of view of the lenses. In a few hours the nebula so changed its form and position, that, being immediately over the portion of the roof between the front or bow lens and that in the centre of the roof, its central section was invisible; but the extremities of that part which I had seen in the first instance through the upper plane window of the bow were now clearly visible from the upper windows of either side. What had at first been a mere greatly elongated oval, with a species of rapidly diminishing tail at each extremity, had now become an arc spanning no inconsiderable part of the space above me, narrowing rapidly as it extended downwards and sternwards. Presently it came in view through the upper lens, but did not obscure in the least the image of the stars which were then visible in the metacompass. I very soon ascertained that the cloudlet consisted, as I had supposed in the former case, of a multitude of points of light less brilliant than the stars, the distance between which became constantly wider, but which for some time were separately so small as to present no disc that any magnifying power at my command could render measurable. In the meantime, the extremities visible through the other windows were constantly widening out till lost in the spangled darkness. By and by, it became impossible with the naked eye to distinguish the individual points from the smaller stars; and shortly after this the nearest began to present discs of appreciable size but somewhat irregular shape. I had now no doubt that I was about to pass through one of those meteoric rings which our most advanced astronomers believe to exist in immense numbers throughout space, and to the Earth's contact with or approach to which they ascribe the showers of falling, stars visible in August and November. Ere long, one after another of these bodies passed rapidly before my sight, at distances varying probably from five yards to five thousand miles. Where to test the distance was impossible, anything like accurate measurement was equally out of the question; but my opinion is, that the diameters of the nearest ranged from ten inches to two hundred feet. One only passed so near that its absolute size could be judged by the marks upon its face. This was a rock-like mass, presenting at many places on the surface distinct traces of metallic veins or blotches, rudely ovoid in form, but with a number of broken surfaces, one or two of which reflected the light much more brilliantly than others. The weight of this one meteoroid was too insignificant as compared with that of the Astronaut seriously to disturb my course. Fortunately for me, I passed so nearly through the centre of the aggregation that its attraction as a whole was nearly inoperative. So far as I could judge, the meteors in that part of the ring through which I passed were pretty evenly distributed; and as from the appearance of the first which passed my window to the disappearance of the last four hours elapsed, I conceived that the diameter of the congeries, measured in the direction of my path, which seemed to be nearly in the diameter of their orbit, was about 180,000 miles, and probably the perpendicular depth was about the same.

I may mention here, though somewhat out of place, to avoid interrupting the narrative of my descent upon Mars, the only interesting incident that occurred during the latter days of my journey—the gradual passage of the Earth off the face of the Sun. For some little time after this the Earth was entirely invisible; but later, looking through the telescope adjusted to the lens on that side, I discerned two very minute and bright crescents, which, from their direction and position, were certainly those of the Earth and Moon, indeed could hardly be anything else.

Towards the thirtieth day of my voyage I was disturbed by the conflicting indications obtained from different instruments and separate observations. The general result came to this, that the discometer, where it should have indicated a distance of 333, actually gave 347. But if my speed had increased, or I had overestimated the loss by changes of direction, Mars should have been larger in equal proportion. This, however, was not the case. Supposing my reckoning to be right, and I had no reason to think it otherwise, except the indication of the discometer, the Sun's disc ought to have diminished in the proportion of 95 to 15, whereas the diminution was in the proportion of 9 to 1. So far as the barycrite could be trusted, its very minute indications confirmed those of the discometer; and the only conclusion I could draw, after much thought and many intricate calculations, was that the distance of 95 millions of miles between the Earth and the Sun, accepted, though not very confidently, by all terrestrial astronomers, is an over-estimate; and that, consequently, all the other distances of the solar system have been equally overrated. Mars consequently would be smaller, but also his distance considerably less, than I had supposed. I finally concluded that the solar distance of the Earth was less than 9 millions of miles, instead of more than 95. This would involve, of course, a proportionate diminution in the distance I had to traverse, while it did not imply an equal error in the reckoning of my speed, which had at first been calculated from the Earth's disc, and not from that of the Sun. Hence, continuing my course unchanged, I should arrive at the orbit of Mars some days earlier than intended, and at a point behind that occupied by the planet, and yet farther behind the one I aimed at. Prolonged observation and careful calculation had so fully satisfied me of the necessity of the corrections in question, that I did not hesitate to alter my course accordingly, and to prepare for a descent on the thirty-ninth instead of the forty-first day. I had, of course, to prepare for the descent very long before I should come within the direct influence of the attraction of Mars. This would not prevail over the Sun's attraction till I had come within a little more than 100,000 miles of the surface, and this distance would not allow for material reduction of my speed, even were I at once to direct the whole force of the apergic current against the planet. I estimated that arriving within some two millions of miles of him, with a speed of 45,000 miles per hour, and then directing the whole force of the current in his direction, I should arrive at his surface at a speed nearly equal to that at which I had ascended from the Earth. I knew that I could spare force enough to make up for any miscalculation possible, or at least probable. Of course any serious error might be fatal. I was exposed to two dangers; perhaps to three: but to none which I had not fully estimated before even preparing for my voyage. If I should fail to come near enough to the goal of my journey, and yet should go on into space, or if, on the other hand, I should stop short, the Astronaut might become an independent planet, pursuing an orbit nearly parallel to that of the Earth; in which case I should perish of starvation. It was conceivable that I might, in attempting to avert this fate, fall upon the Sun, though this seemed exceedingly improbable, requiring a combination of accidents very unlikely to occur. On the other hand, I might by possibility attain my point, and yet, failing properly to calculate the rate of descent, be dashed to pieces upon the surface of Mars. Of this, however, I had very little fear, the tremendous power of the apergy having been so fully proved that I believed that nothing but some disabling accident to myself—such as was hardly to be feared in the absence of gravitation, and with the extreme simplicity of the machinery I employed—could prevent my being able, when I became aware of the danger, to employ in time a sufficient force to avert it. The first of these perils, then, was the graver one, perhaps the only grave one, and certainly to my imagination it was much the most terrible. The idea of perishing of want in the infinite solitude of space, and being whirled round for ever the dead denizen of a planet one hundred feet in diameter, had in it something even more awful than grotesque.

On the thirty-ninth morning of my voyage, so far as I could calculate by the respective direction and size of the Sun and of Mars, I was within about 1,900,000 miles from the latter. I proceeded without hesitation to direct the whole force of the current permitted to emerge from the apergion directly against the centre of the planet. His diameter increased with great rapidity, till at the end of the first day I found myself within one million of miles of his surface. His diameter subtended about 15', and his disc appeared about one-fourth the size of the Moon. Examined through the telescope, it presented a very different appearance from that either of the Earth or of her satellite. It resembled the former in having unmistakably air and water. But, unlike the Earth, the greater portion of its surface seemed to be land; and, instead of continents surrounded by water, it presented a number of separate seas, nearly all of them land-locked. Around the snow-cap of each pole was a belt of water; around this, again, a broader belt of continuous land; and outside this, forming the northern and southern boundary between the arctic and temperate zones, was another broader band of water, connected apparently in one or two places with the central, or, if one may so call it, equatorial sea. South of the latter is the one great Martial ocean. The most striking feature of this new world, as seen from this point, was the existence of three enormous gulfs, from three to five thousand miles in length, and apparently varying in breadth from one hundred to seven hundred miles. In the midst of the principal ocean, but somewhat to the southward, is an island of unique appearance. It is roughly circular, and, as I perceived in descending, stands very high, its table-like summit being some 4000 feet, as I subsequently ascertained, above the sea-level. Its surface, however, was perfectly white—scarcely less brilliant, consequently, than an equal area of the polar icefields. The globe, of course, revolved in some 4-1/ hours of earthly time, and, as I descended, presented successively every part of its surface to my view. I speak of descent, but, of course, I was as yet ascending just as truly as ever, the Sun being visible through the lens in the floor, and reflected upon the mirror of the discometer, while Mars was now seen through the upper lens, and his image received in the mirror of the metacompass. A noteworthy feature in the meteorology of the planet became apparent during the second day of the descent. As magnified by the telescope adjusted to the upper lens, the distinctions of sea and land disappeared from the eastern and western limbs of the planet; indeed, within 15° or an hour of time from either. It was plain, therefore, that those regions in which it was late evening or early morning were hidden from view; and, independently of the whitish light reflected from them, there could be little doubt that the obscuration was due to clouds or mists. Had the whitish light covered the land alone, it might have been attributed to a snowfall, or, perhaps, even to a very severe hoar frost congealing a dense moisture. But this last seemed highly improbable; and that mist or cloud was the true explanation became more and more apparent as, with a nearer approach, it became possible to discern dimly a broad expanse of water contrasting the orange tinge of the land through this annular veil. At 4h. on the second day of the descent, I was about 500,000 miles from Mars, the micrometer verifying, by the increased angle subtended by the diameter, my calculated rate of approach. On the next day I was able to sleep in security, and to devote my attention to the observation of the planet's surface, for at its close I should be still 15,000 miles from Mars, and consequently beyond the distance at which his attraction would predominate over that of the Sun. To my great surprise, in the course of this day I discerned two small discs, one on each side of the planet, moving at a rate which rendered measurement impossible, but evidently very much smaller than any satellite with which astronomers are acquainted, and so small that their non-discovery by terrestrial telescopes was not extraordinary. They were evidently very minute, whether ten, twenty, or fifty miles in diameter I could not say; neither of them being likely, so far as I could calculate, to come at any part of my descent very near the Astronaut, and the rapidity of their movement carrying them across the field, even with the lowest power of my telescopes, too fast for measurement. That they were Martial moons, however, there could be no doubt.