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THE NEW ASTRONOMY.

II. THE PLANETS.

WHEN We look up at the heavens we see, if we watch through the night, the host of stars rising in the east and passing above us to sink in the west, always at the same distance and in unchanging order, each seeming a point of light as feeble as the glow-worm's shine in the meadow over which they are rising, each flickering as though the evening wind would blow it out. The infant stretches forth his hand to grasp the Pleiades; but when the child has become an old man the "Seven Stars" are still there unchanged, dim only in his aged sight, and proving themselves the enduring substance, while it is his own life which has gone, as the shine of the glow-worm in the night. They were there just the same a hundred generations ago, before the pyramids were built, and they will tremble there still, when the pyramids have been worn down to dust with the blowing of the desert sand against their granite sides. They watched the earth grow fit for man long before man came, and they will doubtless be shining on when our poor human race itself has disappeared from the surface of this planet.

Probably there is no one of us who has not felt this solemn sense of their almost infinite duration as compared with his own little portion of time, and it would be a worthy subject for our thought if we could study them in the light that the New Astronomy sheds for us on their nature. But I must here confine myself to the description of but a few of their number, and speak, not of the infinite multitude and variety of stars, each a self-shining sun, but only of those which move close at hand; for it is not true of quite all that they keep at the same distance and order.

Of the whole celestial army which

the naked eye watches, there are five stars which do change their places in the ranks, and these change in an irregular and capricious manner, going about among the others, now forward and now back, as if lost and wandering through the sky. These wanderers were long since known by distinct names, as Mercury, Venus, Mars, Jupiter and Saturn, and believed to be nearer than the others; and they are, in fact, companions to the earth, and fed, like it, by the warmth of our sun, and, like the moon, are visible by the sunlight which they reflect to us. With the earliest use of the telescope it was found that while the other stars remained in it mere points of light as before, these became magnified into disks on which markings were visible, and the markings have been found with our modern instruments, in one case at least, to take the appearance of oceans and snow-capped continents and islands. These, then, are not uninhabitable self-shining suns, but worlds, vivified from the same fount of energy that supplies us, and the possible abode of creatures like ourselves.

"Properly speaking," it is said, "man is the only subject of interest to man"; and if we have cared to study the uninhabitable sun because all that goes on there is found to be so intimately related to us, it is surely a reasonable curiosity which prompts the question so often heard as to the presence of life on these neighbour worlds, where it seems not impossible that life should exist. Even the very little we can say in answer to this question will always be interesting; but we must regretfully admit at the outset that it is but little, and that with some planets, like Mercury and Venus, the

great telescopes of modern times. cannot do much more than those of Galileo, with which our New Astronomy had its beginning, though perhaps it should be added that Schiaparelli's late observations of these two planets seem to show that they always turn the same face towards the sun, just as the moon does towards the earth. Let us leave these, then, and pass out to the confines of the planetary system.

The outer planets, Neptune and Uranus, remain pale disks in the most powerful instruments-the first attended by a single moon, the second by four, barely visible; and there is so very little yet known about their physical features that we shall do better to give our attention to one of the most interesting objects in the whole heavens-the planet Saturn, on which we can at any rate see enough to arouse a lively curiosity to know more.

In all the heavens there is no more wonderful object than Saturn, for it preserves to us an apparent type of the plan on which all the worlds were originally made. The planet, we must remember, is a globe nearly seventy thousand miles in diameter, and the outermost ring is over one hundred and fifty thousand miles across. The belts on the globe show delicate tints of brown and blue, and parts of the ring are, as a whole, brighter than the planet; but this ring consists of at least three main divisions, each itself containing separate features. First is the gray outer ring, then the middle one, and next the curious "crape" ring, very much darker than the others, looking like a belt where it crosses the planet, and apparently feebly transparent, for the outline of the globe has been seen (though not very distinctly) through it. The whole system of rings is of the most amazing thinness, for it is probably thinner in proportion to its size than the paper on which this is printed is to the width of the page; and when it

is turned edgewise to us, it disappears to all but the most powerful telescopes, in which it looks then like the thinnest conceivable line of light, on which the moons have been seen projected, apparently like beads sliding along a golden wire. The rotation of the ring has been made out by direct observations; and the whole is in motion about the globea motion so smooth and steady that there is no flickering in the shadow "Where Saturn's steadfast shade sleeps on its luminous ring."

What is it? No solid could hold together under such conditions; we can hardly admit the possibility of its being a liquid film extended in space; and there are difficulties in admitting it to be gaseous. But if not a solid, a liquid, or a gas, again what can it be? It was suggested nearly two centuries ago that the ring might be composed of innumerable little bodies like meteorites, circling round the globe so close together as to give the appearance we see, much as a swarm of bees at a distance looks like a continuous cloud; and this remains the most plausible solution of what is still in some degree a mystery. Whatever it be, we see in the ring the condi tion of things which, according to the nebular hypothesis, once pertained to all the planets at a certain stage of their formation; and this, with the extraordinary lightness of the globe (for the whole planet would float on water), make us look on it as still in the formative stage of uncondensed matter, where the solid land as yet is not, and the foot could find no resting place. Astrology figured Saturn as "spiteful and cold-an old man melancholy"; but if we may indulge such a speculation, modern astronomy rather leads us to think of it as in the infancy of its life, with every process of planetary growth still in its future, and separated by an almost unlimited stretch of years from the time

when life under the conditions in which we know it can ever begin to exist.

Like this appears also the condition of Jupiter, the greatest of the planets, whose globe, eighty-eight thousand miles in diameter, turns so rapidly that the centrifugal force causes a visible flattening. The belts which stretch across its disk are of all delicate tints-some pale blue, some of a crimson lake; a seagreen patch has been seen, and at intervals of late years there has been a great oval red spot, which has now nearly gone. The belts are largely, if not wholly, formed of rolling clouds, drifting and changing under our eyes.

Photography, in the skilful hands of the late Professor Henry Draper, gave us reason to suspect the possibility that a dull light is sent to us from parts of the planet's surface besides what it reflects, as though it were still feebly glowing like a nearly-extinguished sun. On the whole, a main interest of these features to us lies in the presumption they create that the giant planet is not yet fit to be the abode of life, but is more probably in a condition like that of our earth millions of years since, in a past so remote that geology only infers its existence, and long before our own race began to be. That science, indeed, itself teaches us that such all but infinite periods are needed to prepare a planet for man's abode, that the entire duration of his race upon it is probably brief in comparison.

III.-MARS AND THE MOON.

We pass by the belt of Asteroids, and over a distance many times greater than that which separates the earth from the sun, till we approach our own world. Here, close beside it as it were, in comparison with the enormous spaces which in

tervene between it and Saturn and Jupiter, we find a planet whose size and features are in striking contrast to those of the great globe we have just quitted. It is Mars, which shines so red and looks so large in the sky because it is so near, but whose diameter is only about half that of our earth. This is, indeed, properly to be called a neighbour world, but the planetary spaces are so immense that this neighbour is at closest still about thirty-four million miles away.

The cause of the red colour of Mars has never been satisfactorily ascertained. Its atmosphere does not appear to be dark enough to produce such an effect, and perhaps as probable an explanation as any is one the suggestion of which is a little startling at first. It is that vegetation on Mars may be red instead of green! There is no intrinsic improbability in the idea, for we are even to-day unprepared to say with any certainty why vegetation is green here, and it is quite easy to conceive of atmospheric conditions which would make red the best absorber of the solar heat. Here, then, we find a planet on which we obtain many of the conditions of life which we know ourselves, and here, if anywhere in the system, we may allowably inquire for evidence of the presence of something like our own race; but though we may indulge in supposition, there is unfortunately no prospect that with any conceivable improvement in our telescopes we shall ever obtain anything like certainty. We cannot assert that there are any bounds to man's invention, or that science may not, by some means as unknown to us as the spectroscope was to our grandfathers, achieve what now seems impossible; but to our own present knowledge no such means exist, though we are not forbidden to look at the ruddy planet with the feeling that it may hold possibilities more interesting to our humanity than all the wonders of

the sun, and all the uninhabitable immensities of his other worlds.

The study of the moon's surface has been continued now from the time of Galileo, and of late years a whole class of competent observers has been devoted to it, so that astronomers engaged in other branches have oftener looked on this as a field for occasional hours of recreation with the telescope than made it a constant study. I can recall one or two such hours in earlier observing days, when, seated alone under the over-arching iron dome, the world. below shut out, and the world above opened, the silence disturbed by no sound but the beating of the equatorial clock, and the great telescope itself directed to some hill or valley of the moon, I have been so lost in gazing that it seemed as though a look through this, the real magic tube, had indeed transported me to the surface of that strange alien world. Fortunately for us, the same spectacle has impressed others with. more time to devote to it and more ability to render it, so that we not only have most elaborate maps of the moon for the professional astronomer, but abundance of paintings, drawings and photographs, which give the appearance of its surface as seen in powerful telescopes.

Let us remember that the moon is a little over twenty-one hundred miles in diameter; that it weighs, bulk for bulk, about two-thirds what the earth does, so that, in consequence of this and its smaller size, its total weight is only about oneeightieth of that of our globe; and that the force or gravity at its surface being only one-sixth of what it is here, eruptive explosions can send their products higher than in our volcanoes. Its area is between four and five times that of the United States, and its average distance is a little less than two hundred and forty thousand miles.

This is very little in comparison

with the great spaces we have been traversing in imagination; but it is absolutely very large, and across it the valleys and mountains of this our neighbour disappear, and present to the naked eye only the vague lights and shades known to us from childhood as "the man in the moon," and which were the puzzle of the ancient philosophers, who often explained them as reflections of the earth itself, sent back to us from the moon as from a mirror. It, at any rate, shows that the moon always turns the same face towards us, since we always see the same "man," and that there must be a back to the moon which we never behold at all; and, in fact, nearly half of this planet does remain forever hidden from human observation.

The "man in the moon " disappears when we are looking in a telescope, because we are then brought so near to details that the general features are lost; but he can be seen in any photograph of the full moon by viewing it at a sufficient distance, and making allowance for the fact that the contrasts of light and shade appear stronger in the photograph than they are in reality. The best time for viewing the moon, however, is not at the full, but at the close of the first quarter; for then we see that the sunlight, falling slantingly on it, casts shadows which bring out all the details so that we can distinguish many of them even here. Most of the names of the main features of the lunar surface were bestowed by the earlier observers in the infancy of the telescope, when her orb

"Through optic glass the Tuscan artist 'viewed,'

At evening from the top of Fiesole
Or in Valdarno, to descry new lands,
Rivers or mountains in her spotty globe."

The signs of age are on the moon. It seems pitted, torn, and rent by the past action of long-dead fires, till its surface is like a piece of porous cinder seen through a magnifying-glass -a burnt-out cinder of a planet,

which rolls through the void like a ruin of what has been; and, more significant still, this surface is wrinkled everywhere, till the analogy with an old and shrivelled face, or hand, or fruit, where the puckered skin is folded about a shrunken centre, forces itself upon our attention, and suggests a common cause,-a something underlying the analogy, and making it more than a mere resemblance.

The moon, then, is dead; and if it ever was the home of a race like ours, that race is dead too. I have said that our New Astronomy modifies our view of the moral universe as well as of the physical one; nor do we need a more pregnant instance than in this before us. In these days of the decay of old creeds of the Eternal, it has been sought to satisfy man's yearning toward it by founding a new religion whose God is Humanity, and whose hope lies in a future existence of our own race, in whose collective being the individual who must die may fancy his aims and purposes perpetuated in an endless progress. But, alas for hopes looking to this alone. We are here brought to face the solemn thought that, like the individual, though at a little further date, humanity itself may die!

Before we leave this dead world, let us take a last glance at one of its fairest scenes-that which we obtain when looking at a portion on which the sun is rising. Its nearly level rays stretch elsewhere over a surface that is, in places, of a strangely smooth texture, contrasting with the ruggedness of the ordinary soil, which, gathered into low plaits, with the texture we have spoken of, look "Like marrowy crapes of China silk,

Or wrinkled skin on scalded milk,'

as they lie, soft and almost beautiful, in the growing light.

When its first beams are kindling, the summits cast their shadows illimitedly over the darkening plains away on the right, until they melt away in the night-a night which is not utterly black, for even here a subdued radiance comes from the earth-shine of our own world in the sky.

Let us leave here the desolation about us, happy that we can come back at will to that world, our own familiar dwelling, where the meadows are still green, and the birds still sing, and where, better yet, still dwells our own kind-surely the world, of all we have found in our wanderings, which we should ourselves have chosen to be our home.

A SOUL.

SAY not I have a soul; I am a soul,
And have a body builded for my need,
That I, a soul, may in this great world-school
Study the Master's works. My earthly house
Has wondrous windows; mimic galleries lead
Divinest sounds to me,-deep lessons spelled
By loving lips, and vast world-melodies.
I am a soul, set in a sphere compact
Of transient elements.

Of these, a little handful serves for home,
For medium of touch 'twixt me and earth,
The while I stay-gives fire and food and rest.
Shall the base stuff strike into me a stain,
Leave pungent, earthly odour? Soul of all,
Attract me, lest the body should
Transcend a dwelling's use.

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