WONDERS OF THE HEAVENS,

CAMILLE FLAMMARION.

FROM THE FRENCH BY MRS. NORMAN LOGKYER

NEW YORK:

SCRIBNER, ARMSTRONG, & CO.

1874.

transfhb

1>. O. PUBLIC LIB&AjfiT SEPT. 10. 19*0

I

CONTENTS.

BOOK I.

I. NIGHT

II. THE HEAVENS ....

III. INFINITE SPACE

IV. GENERAL ARRANGEMENT OF THE UNIVEBSE

V. CLUSTERS AND NEBULA - •

VI. THE MILKY WAY . .

PAO«

3

9

16 10 29 43

BOOK II.

I. THE SIDEREAL WORLD . .... 55

II. THE NORTHERN CONSTELLATIONS ... 67

III. THE ZODIAC 74

IV. SOUTHERN CONSTELLATIONS .... 89

V. THE NUMBER OF THE STARS THEIR DISTANCES . 101

VI. VARIABLE STARS TEMPORARY STARS STARS

SUDDENLY VISIBLE OR INVISIBLE . . .113

VII. DISTANT UNIVERSES DOUBLE MULTIPLE, AND

COLOURED SUNS . .... 120

BOOK III.

I. THE PLANETARY SYSTEM II. THE SUN .

in. the sun (continued)

133

140 150

Contents.

	PAGE
IV.	MERCURY 158
V.	VENDS							162
VI.	MARS							168
VII.	JUPITER .							173
VJII.	SATURN .							177
IX.	URANUS .							186
X.	NEPTUNE							190
XI.	COMETS .							195
XII.	comets {continued)						204
		B	OOK	IV.

I. THE TERRESTRIAL GLOBE

II. PROOFS THAT THE EARTH IS ROUND THAT IT

TURNS ON AN AXIS, AND REVOLVES ROUND THE SUN . ......

III. THE MOON .....

iv. the moon {continued) .....

V. ECLIPSES

215

223 237 246 259

BOOK V.

I. THE PLURALITY OF INHABITED WORLDS II. THE CONTEMPLATION OF THE HEAVENS

273 282

SOOK L

NIGHT.

* O nuit ! que ton langage est sublime pour moi, Lorsque, seul et pensif, aussi calme que toi, Contemplant les soleils dont ta robe est paree, J'erre et medite en paix sous ton ombre sacree ! '

De Fontanes.

O Night, how sublime is thy language to me! ... . Where are the souls to whom the spectacle of starry night is not an eloquent discourse ? Where are those who have not been sometimes arretted in the jresence of the bright worlds which hover -v* •"* onr h*e**is, a id who have not sought for the key of the great enigma of creation ? The solitary hours of night are in truth the most beautiful of all our hours, those in which we have the faculty of placing ourselves in intimate communication with great and holy Nature. Far from spreading a veil over the universe, as is sometimes said, they only efface those which the sun produces in the atmo- sphere. The orb of day conceals from us the splendours of the firmament ; it is during the night that the panoramas of the sky are open to us. 'At the hour of midnight, the heavenly vault is strewn with stars, like isles of light in the midst of an ocean extending over our heads. Who can con- template them and bring back his looks to the earth without feeling sad regrets, and without longing for wings in order to take flight and be blended with them, or be lost amidst their immortal light ?*

In the midst of darkness our eyes gaze freely on the sky, piercing the deep azure of the apparent vault, above which

4 Marvels of the Heavens.

the stars shine. They traverse the white constellated regions, visiting distant regions of space, where the most brilliant stars lose their brightness by distance ; they go beyond this unexplored expanse, and mount still higher, as far as those faint nebulae whose diffused brightness seems to mark the limits of the visible. In this immense passage of sight thought with rapid wings accompanies the forerunning visual ray, carried away by its flight and wonderingly contemplating these distant splendours. The purity of the heavenly pros- pect awakens that eternal predisposition to melancholy which dwells in the depths of our souls, and soon the spectacle ab- sorbs us in a vague and indefinable reverie. It is then that thousands of questions spring up in our minds, and that a thousand points of interrogation rise to our sight. The problem of creation is a great problem ! The science of the stars is an immense science; its mission is to embrace the universality of created things ! At the remembrance of these impressions, does it not appear that the man who does not feel any sentiment of admiration before the picture of the starry splendour, is not yet worthy of receiving on his brow the crown of intelligence ?

Night is, in truth, the hour of solitude, in which the con- templative soul is regenerated in the universal peace. We become ourselves ; we are separated from the factitious life of the world, and placed in the closest communion with nature and with truth. A poetess, Madame de Girardin, has de- scribed these impressions with an exquisite touch : —

' Voici l'heure oil tombe le voile Qui, le jour, cache mes ennuis : Mon cceur a la premiere etoile S'ouvre comme une fleur de nuit.

On nage, on plane dans l'espace, Par l'esprit du soir emporte ; On n'est plus qu'une ombre qui passe, Une ame dans l'immensite.

Night. *

D'un monde trompeur rien ne reste :

Ni chaine, ni loi, ni douleur ;

Et Fame, papillon celeste,

Sans crime peut choisir sa fleur.

0 nuit ! pour moi brillante et sombre, Je trouve tout dans ta beaute ; Tu reunis l'etoile et 1'ombre, Le mystere et la verite.'

Edward Young, he who, in Newton's language, gave us ' Night Thoughts,' was sometimes exalted to magnificent thought in his hymns : —

4 0 Majestic Night ! Nature's great ancestor ! Day's elder-born And fated to survive the transient sun ! By mortals and immortals seen with awe ! A starry crown thy raven brow adorns ; An azure zone, thy waist ; clouds in heaven's loom Wrought through varieties of shape and shade, In ample folds of drapery divine, Thy flowing mantle form, and, heaven throughout, Voluminously pour thy pompous train. Thy gloomy grandeurs (Nature's most august, Inspiring aspect !) claim a grateful verse ; And like a sable curtain starr'd with gold, Drawn o'er my labours pass'd, shall close the scene.

And what, 0 man ! so worthy to be sung ? What more prepares us for the songs of heaven ? Creation of archangels is the theme ! What to be sung so needful ? What so well Celestial joys prepares us to sustain ?

• e o o *

Glance thy thought, and think of more than man.

e e . « © *

This gorgeous apparatus, this display, This ostentation of creative power.

6 Marvels of the Heavens,

This theatre, — what eye can take it in?

By what dhine enchantment was it raised,

For minds of this first magnitude to launch

In endless speculation and adore ?

One seen by day, by night ten thousand shine ;

And light us deep into the Deity !

How boundless in magnificence and might !

0 what a confluence of ethereal fires,

From urns unnumber'd, down the steep of heaven,

Streams to a point, and centres in my sight !

Nor tarries there ; I feel it at my heart.

My heart, at once, it humbles and exalts ;

Lays it in dust and calls us to the skies.

o o e e o

0 let me gaze ! . . . . 0 let me think ! Thought too is wilder'd here ; In midway flight Imagination tires ; Yet soon reprunes her wing to soar anew, Her point unable to forbear or gain ; So great the pleasure, so profound the plan !

e e e e e

Now go, Ambition ! boast thy boundless might In conquest o'er the tenth part of a grain.'

Of all the sciences, Astronomy is the one which can enlighten us best on our relative value, and make us under- stand the relation which connects the Earth with the rest of creation. Without it, as the history of past centuries testifies, it is impossible for us to know where we are or who we are, or to establish an instructive comparison between the place which we occupy in space and the whole of the universe : without it we should be both ignorant of the actual extent of our country, its nature, and the order to which it belongs Enclosed in the dark meshes of ignorance, we cannot form the slightest idea of the general arrangement of the world; a thick fog covers the narrow horizon which contains us, and our mind remains incapable of soaring above the daily

Night. 7

theatre of life, and of going beyond the narrow sphere traced by the limits of the action of our senses. On the other hand, when the torch of the Science of the Worlds enlightens us, the scene changes, the vapours which darkened the horizon fade away, our mistaken eyes contemplate in the serenity of a pure sky the immense work of the Creator. The Earth appears like a globe poised under our steps ; thousands of similar globes are rocked in ether; the world enlarges in proportion as the power of our examination increases, and from that time universal creation developes itself before us in its reality, establishing both our rank and our relation with the numerous similar worlds which constitute the universe.

It is at night that this spectacle must be demanded — it is night which must be invoked in concert with the sacred bards whose lyre is worthy to sing its greatness : —

* 0 nuit ! deroulez en silence Les pages du livre des cieux ; Astres, gravitez en cadence Dans vos sentiers liarmonieux ; Durant ces heures solennelles, Aquilons, repliez vos ailes ; Terre, assoupissez vos echos ; Etend tes vagues sur les plages, 0 iner! et berce les imager, Du Dieu qui t'a donne tes flots.'°

The silence and profound peace of a starry night present an appropriate scene to our contemplative faculty, and no time is more propitious to the elevation of the soul towards the beauties of the heavens. But the poetry of the sight of these appearances will be soon surpassed by the magnificence of the reality. And it is on this point that we must first insist, in order to get rid of all delusions caused by the senses. It seems to me right to remove the causes of error which may leave false impressions on our minds ; it is com-

* Lamartine.

8 Marvels of the Heavens,

pletely useless, if not dangerous, to devote the first part of an astronomical discourse to describing apparent phenomena, which will afterwards have to be proved false. Let us not follow this troublesome road; let us keep away from the ordinary path, and begin, on the contrary, by raising the veil, in order to allow the reality to shine. Poetry, whose harmonious breath has just hushed our suspended souls, will not vanish on that account ; it will rather regain a fresh aspect and new life, and, above all, a greater energy. Fiction can never be superior to truth ; the latter is a source of inspiration to us, richer and more fruitful than the former.

II.

THE HEAVENS.

* Oh ! depuis cette terre ou rampent les mortels, De l'espace fuyant les vides eternels, Qui sondera des cieux l'insondable distance, Quand apres l'infini, l'infini recommence ! '

The shade which spreads over the hemisphere in the absence of the Sun, from its setting to its rising, is only a partial phenome- non, circumscribed by the Earth, and in which the remainder of the universe does not participate. When we are enveloped in the calm silence of profound night, we are inclined to extend the scene which surrounds us to the entire universe, as if our world were the centre and pivot of creation. A few moments' reflection will suffice to prove how great this illusion is, and to prepare us for the concep- tion of the whole world. It is, indeed, evident that the Sun cannot illuminate all sides of the same object at once, but only those which are turned towards it, only lighting up half the terrestrial globe at one time ; hence it fol- lows that night is nothing more than the state of the

Fig. 1. — Night and Day.

10 Marvels of the Heavens,

non-luminous part. If we imagine the terrestrial globe suspended in space, we shall understand that the side turned towards the Sun is alone illuminated, whilst the opposite hemisphere remains in shadow, and that this shadow pre- sents the aspect of a cone. Moreover, as the Earth turns on itself, all its portions are presented successively to the Sun and pass successively into this shadow, and it is this which constitutes the succession of day and night in every country of the world. This simple coup d'ceil suffices to show that the phenomenon to which we give the name of night belongs really to the Earth, and that the heavens and the rest of the universe are independent of it.

This is the reason why, if at any hour of the night we let our minds soar above the terrestrial surface, it will follow that, far from remaining always in the night, we shall again find the Sun pouring forth his floods of light through space. If we carry ourselves away as far as one of the planets which, like the Earth, revolves in the region of space where we are, we shall understand that the night of the Earth does not extend to those other worlds, and that the period which with us is consecrated to repose does not extend its influence there. When all beings are buried in the stillness of silent night here-— above, the forces of nature continue the exercise of their brilliant functions — the Sun shines, life radiates, movement is not suspended, and the reign of light pursues its dominant action in the heavens (as on the opposite hemi- sphere to ours), at the same hour when sleep overcomes all beings on the hemisphere we inhabit.

It is important that we should know, first of all, how to habituate ourselves to this idea of the isolation of the Earth in space, and to believe that all the phenomena which we observe upon this globe are peculiar to it and foreign to the rest of the universe. Thousands and thousands of similar globes revolve like it in space. I do not now prove the truth of my assertions, but my readers will not doubt them, and will be willing to take my word, reminding me later to

The Heavens. 11

justify all that I shall have stated. Moreover, I promise them to do this as soon as possible ; but I shall ask their permission to develope at once, in outline, a general idea of the universe.

One of the most fatal delusions which it is important we should get rid of at once, is that which presents the Earth as the lower half of the universe, and the heavens as its upper half. There is nothing in the world more false than this. The heavens and the Earth are not two separate creations, as we have had repeated to us thousands and thousands of times. They are only one. The Earth is in the heavens. The heavens are infinite space, indefinite expanse, a void without limits ; no frontier circumscribes them, they have neither beginning nor end, neither top nor bottom, right nor left : there is an infinity of spaces which succeed each other in every direction. The Earth is a little material globe, placed in this space without support of any kind, like a bullet which sustains itself alone in the air, like the little captive balloons which rise and float in the atmosphere when the thin cord which retains them is cut. The Earth is a star in the heavens; it forms part of them; it, in company with a great many other globes similar to it, peoples them ; it is isolated in them ; and all these other globes also float isolated in space. This conception of the universe is not only very important, but it is also a truth which it is absolutely necessary should be well fixed in the mind, otherwise three-quarters of the astro- nomical discoveries would remain incomprehensible. Here, then, is this first point well understood and thoroughly established in our thoughts. The heavens surround us on every side. In this space the Earth is a globe suspended ; but the Earth is not alone in space. All those stars which sparkle in the heavens are isolated globes, suns shining by their own light ; they are very distant from us ; but there are stars nearer which resemble much more the one we inhabit, in the sense that they are not suns, but dark earths receiving, like ours, light from our Sun. These world*? called ' planets '

12 Marvels of the Heavens.

are grouped in a family ; ours is one member of this family. At the centre of this group shines our Sun, a source of light which illuminates it, and of heat which warms it. Floating in the bosom of the space which surrounds it on every side, this group is like a fleet of many boats rocked in the ocean of the heavens.

A multitude of suns, surrounded like ours with a family of which they are the foci and the light-givers, float likewise in all parts of the expanse. These suns are the stars with which the fields of heaven are scattered. In spite of the ap- pearance caused by perspective, immense spaces separate all these systems from ours, spaces so great that the highest figures of our great numeration can scarcely number the smallest amongst them. A distance that our figures can scarcely express also separates these stars from each other, extending from depths unto depths.

Notwithstanding these prodigious intervals, these suns are in number so considerable that their numeration as yet exceeds all our means; millions joined to millions are in- adequate to enumerate the multitude ! . . . . Let the mind try if it is possible to represent to itself at one time this con- siderable number of systems and the distances which separate them one from the other! Confused and soon humbled at the aspect of this infinite richness, it will only learn to admire in silence this indescribable wonder. Continually rising on the other side of the heavens, going beyond the distant shores of this ocean without limits, it will endlessly discover fresh new space, and new worlds will reveal themselves to our eagerness; heavens will succeed to heavens, spheres to spheres ; after deserts of expanse will open other deserts, after immensities other immensities ; and even when carried away without rest, during centuries, with the rapidity of thought, the soul would continue its flight beyond the most inaccessible limits that imagination could conceive, — there even the infinite of an unexplored expanse would remain still open before it; the infinite of space would oppose itself to

The Heavens. 1 3

the infinite of time ; endlessly rivalling, without our ever being able to take away from the other : and the spirit will be arrested, overcome with fatigue, at the entrance of infinite creation, as if it had not advanced a single step in space. Imagination suspends its flight and is stopped humbled.

' Ye stars ! bright legions that, before all time,

Camped on yon plain of sapphire, what shall tell

Your burning myriads but the eye of Him

Who bade through heaven your golden chariots wheel ?

Yet who, earth-born, can see your hosts, nor feel

Immortal impulses — eternity ?

What wonder if the o'erwrought soul should reel

With its own weight of thought, and the wild eye

See fate within your tracks of deepest glory lie ? ' °

The immensity of the heavens has been sung on many lyres ; but how can the song of man express such a reality ? Poets have tried to render it in verse, when one feels the insufneiencv of speech to note the immense thoughts which this wonderful contemplation developes in us.

Had I not reason for stating, as I did, that reality is superior to fiction, even from the point of view of poetical sentiments, — and that the contemplation of actual nature encloses a richer and more fruitful source of inspiration than the illusions of the spectacle offered by our senses ? Instead of an immense night stretching itself to the azure vaults, instead of a robe worked with gold embroideries, or a veil covered with brilliant ornaments, we are in the bosom of life and universal brightness. Night is but an accident, a happy accident, which enables our looks to extend themselves ' beyond the limits which the day marks for us ; we are like a ^aveller reclining in the shadow of a hill, who contemplates the illuminated landscape which is unfolded as far as the distant horizon. Instead of the immobility of dead silence,

* Croly, The Stars.

14 Marvels of the Heavens*

we are present at the spectacle of life on worlds. With the light of truth the arbitrary vaults disappear and heaven opens its depths to us ; the infinite of creation is revealed with the infinite of space, and our Earth, losing the prepon- derance which our pretensions had accorded to it, gives way under our feet and disappears in the shade, losing itselt in the midst of a multitude of similar little worlds. In the freedom of our flight we go beyond the solar regions and take our first sketch of the universe. It is thus that, disabusing ourselves of the first step of the ancient error too long established by appearances, we place ourselves in good condition for study, and prepare ourselves to receive easily the fresh truths which nature will reveal to us.

Allow me, in concluding this chapter, to relate an episode worthy of being more known than it has yet been, because it shows how much more power the real world has, than the empire of fiction. It is taken from the life of the great mathematician, Euler, and it was Arago himself who related it to the Chambre des Deputes at the meeting of the 23rd of March, 1837.

' Euler, the great Euler, was very pious ; one of his friends, a minister of one of the Berlin churches, came to him one day and said, " Religion is lost, faith has no longer any basis, the heart is no longer moved, even by the sight of the beauties, — the wonders of creation. Can you believe it ? I have represented this creation as everything that is beautiful, poetical, and wonderful ; I have quoted ancient philosophers and the Bible itself; half the audience did not listen to me, the other half went to sleep or left the church."

'"Make the experiments which Truth points out to you," replied Euler. "Instead of giving the description of the world from Greek philosophers or the Bible, take the astronomical world, unveil the world such as astronomical research has con- stituted it. In the sermon which has been so little attended t*:, you have probably, according to Anaxagoras, made the Suu equal to the Peloponnesus. Very well! say to your audience

The Heavens. 15

that, according to exact incontestable measurements, our Sun is 1,200,000 times larger than the Earth.

'" You have, doubtless, spoken of the fixed crystal heavens ; say that they do not exist, that comets break through them ; in your explanations planets were only distinguished from stars by movement ; tell them they are worlds, that Jupiter is 1400 times larger than the Earth, and Saturn 900 times ; describe the wonders of the ring; speak ef the multiple moons of these distant worlds.

4 "Arriving at the stars, their distances, do not state miles; the numbers will be too great, they will not appreciate them ; take as a scale the velocity of light ; say that it travels 186,000 miles per second ; afterwards, add that there is no star whose light reaches us under three years ; that there are some of them with respect to which no special means of observation has been used, and whose light does not reach us under thirty years.

4 " On passing from certain results to those which have only great probability, show that, according to all appearance, certain stars could be visible several millions of years alter having been destroyed ; for the light which is emitted by them takes many millions of years to traverse the space which separates them from the Earth."

' Such was, gentlemen, shortened, and only with few modifi- cations in figures, the counsel given by Euler. The advice was followed ; instead of the world of fable, the minister presented the world of science. Euler waited for his friend with im- patience. He arrived at last, with dull eye and in a manner which appeared to indicate despair. The geometer, very astonished, cried out, "What has happened?"

4 " Ah ! Monsieur Euler," replied the minister, " I am very unhappy ; they have forgotten the respect which they owed to the sacred temple, they have applauded me." '

The scientific world was a hundred orbits greater than the world which the most ardent imaginations had dreamt of. There was a thousand times more poetry in the reality than In the fable.

16 Marvels oj the Heavens.

III.

INFINITE SPACE.

' lasense, je croyais embrasser d'un coup d'oeil Ces deserts ou Newton, sur l'aile du genie Planait, tenant en main le compas d Uranie. Je voulais reveler quels sublimes accords Promenent dans lather tous les celestes corps ; Mais devant eux s'abime et s'eteint ma pensee.'

Boucher.

There are truths before which human thought feels itself humiliated and perplexed,, which it contemplates with fear, and without the power to face them, although it understands their existence and necessity : such are those of the infinity of space and eternity of duration. Impossible to define, for all definition could only darken the first idea which is in us, these truths command and rule us. To try and explain them would be a barren hope ; it suffices to keep them before our attention in order that they may reveal to us, at every instant, the immensity of their value. A thousand definitions have been given, we will however neither quote nor recall one of them. But we wish to open space before us and employ ourselves there, in trying to penetrate its depth. The velocity of a cannon-ball from the mouth of the cannon makes swift way, 437 yards per second. But this would be still too slow for our journey through space, as our velocity would scarcely be 900 miles an hour. This is too little. In nature there are movements incomparably more rapid, for instance, the velocity of light. This velocity is 186,000

Infinite Space. 17

miles per second. This will do better; thus we will take this means of transport. Allow me then, by a figure of speech, to tell you that we will place ourselves on a ray of light and be carried away on its rapid course.

Taking the Earth as our starting-point, we will go in a straight line to any point of the heavens. We start. At the end of the first second, we have already traversed 186,000 miles , at the end of the second, 372,000. We continue. Ten seconds, a minute, ten minutes have elapsed, — 111,600,000 miles have been passed. Passing, during an hour, a day, a week, without ever slackening our pace, — during whole months, and even a year, the time which we have traversed is already so long, that expressed in miles, the number of measurement exceeds our faculty of comprehension, and indicates nothing to our mind : they would be trillions, and millions of millions. But we will not interrupt our flight. Carried on without stopping by this same rapidity of 186,000 miles each second, let us penetrate the expanse in a straight line for whole years, fifty years, even a century .... Where are we ? For a long time we have gone beyond the last starry regions which are seen from the Earth, the last that the telescope has visited ; for a long time we travel in other regions, unknown and unexplored. No mind is capable of following the road passed over; thousands of millions joined to thousands of millions express nothing : at the sight of this prodigious expanse the imagination is arrested, humbled. Well ! this is the wonderful point of the problem : we have not ad- vanced a single step in space. We are no nearer a limit than if we had remained in the same place ; we should be able again to begin the same course starting from the point where we are, and add to our voyage a voyage of the same extent ; we should be able to join centuries on centuries in the same itinerary, with the same velocity, — to continue the voyage without end and without rest ; we should be able te guide ourselves in any part of space, left, right, forwards

1 8 Marvels of the Heavens.

backwards, above, below, in every direction ; and when after centuries employed in this giddy course, we should stop our- selves fascinated, or in despair before the immensity eternally open, eternally renewed ; we should again understand that our secular flights had not measured for us the smallest part of space, and that we were not more advanced than at our starting-point. In truth, it is the infinite which surrounds us, as we before expressed it, or the infinite number of worlds. We should be able to float for eternity without ever finding anything before us but an eternally open infinite.

Hence it follows, that all our ideas on space have but a purely relative value. When we say, for instance, to ascend to the sky, to descend under the earth, these expressions are false in themselves, for being situated in the bosom of the infinite, we can neither ascend nor descend : there is no above or below ; these words have only an acceptation relative to the terrestrial surface on which we live.

The universe must, therefore, be represented as an ex- panse without limits, without shores, illimited, infinite, in the bosom of which float suns like that which lights us, and earths like that which poises under our steps. Neither dome, nor vaults, nor limits of any kind ; void in every direction, and in this infinite void an immense quantity of wTorlds, which we will soon describe. It is this universal space that the author of the * Genie de l'Homme ' wished to celebrate, when he expressed the remarkable thoughts which follow :—

' Oui, quand je m'arraerais des ailes de l'Aurore, Pour compter les soleils dont le ciel se decore ; Quand de l'immensite sondant les profondeurs, Ma pensee unirait les nombres aux grandeurs ; Sous ces gouffres sacres egarant mon audace, Quand j'userais le temps a mesurer 1'espace : Je vermis s'ecouler les siecles reunis, Et presse, sans espoir, entre deux infinis, Je nie serais toujours ecarte de moi-nieme, Sans iamais m'approcher de ce vaste problem e.'

19

IV.

GENERAL ARRANGEMENT OF THE UNIVERSE.

STARS ARE DISTRIBUTED IN CLUSTERS.

4 On a sonde ces regions voilees Les bornes du possible ont ete reculees ! Un mortel a pu voir, arme d'un ceil geant, Os'ciller des lueurs aux confins du neant. C'est vous dont notre Hersch^l, 6 pales nebuleuses Decouvrit les clartes qu'on dirait fabuleuses ! II apergut ea vous des germes d'univers, Qui, selon leurs aspects et leurs ages divers, Ou contenaient encor leurs semences fecondes, Ou deja repandaient leurs poussieres de mondes ! Eh bien ! de ces lueurs blanchatres, que les veux Discernent vaguement aux limites des cieux, L'une contient le ciel et le monde ou nous sorames. Ah ! la terre est trop loin ! je ne vois plus les hommes.

J. J. Ampere.

In the bosom of infinite space, the unfathomable extent of which we have tried to comprehend, float rich clusters of stars, each separated by immense intervals. We shall soon show that all the stars are suns like ours, shining with their own light, and foci of as many systems of worlds. Now the stars are not scattered in all parts of space at hazard : they are grouped as the members of many families. If we com- pared the ocean of the heavens with the oceans of the Earth, we should say that the isles which sprinkle this ocean do not 3

20 Marvels of the Heavens.

rise separately in all parts of the sea, but that they are united here and there in archipelagoes more or less rich. A Power as ancient as the existence of matter presided at the creation of these isles, each archipelago of which contains a great number ; not one amongst them has risen spontaneously in an isolated region ; they are all collected in tribes, most ol which count their members bv millions.

These rich groupings of stars have received the name of 1 Nebulae.' This name was given at the time of the invention of astronomical lenses, when these starry tribes were distin- guished only under a diffused, cloudy aspect, which did not enable the eye to distinguish the composing stars. This appearance not revealing in any way the idea of solar clusters, it was thought that they were only phosphorescent, cosmical vapours, whirlwinds of luminous substance, or possibly primitive fluids, whose progressive condensation would in the future effect the formation of new stars. They were thought to assist at the creation of distant worlds, and sometimes, in remarking their different degrees of luminosity, people thought they could infer their relative ages, as in a forest the age of trees of the same species may be known on approach accord- ing to their size or the concentric circles which are formed each year under the bark. Thus the first nebula observed by the aid of the telescope and pointed out as an object of particular nature, the nebula of Andromeda, was considered for three centuries and a half as entirely deprived of stars. Simon Marius of Franconia, who from a musician became an astronomer — very compatible tastes, moreover — describing this oval and whitish appearance, which, more brilliant at the centre, became fainter at the edges, said that it resembled ' the light of a candle (candela) seen at a distance through a sheet of horn.' Only a few years ago a Cambridge astro- nomer counted within the limits of this nebula 1500 little stars, notwithstanding which, the centre still keeps the aspect of a diffused light, in spite of the best instruments. Later, the astronomer Halley thought no more of the star- clusters.

General Arrangement of the Universe. 21

1 In reality,' he states, these spots are nothing more than light coming from an immense space situated in the regions of ether, filled with a diffused and luminous medium by itself.' Others, again, imagined that at that spot the bright- ness of empyrean heaven was seen through an opening in the firmament. Derham said this, the author of astro-theology. But when optical instruments were perfected, this appearance of diffused light was transformed into a brilliant dotting ; in proportion as the power of the telescope became more search- ing, the number of apparent nebulae diminished, and at pre- sent many of those which in Galileo's time were regarded as cosmical clouds are resolved into stars. To be just, it must be added that in revealing the stellar composition of the first nebulae, the telescope showed others whose nature has only quite recently been found out; these nebulae re- main in an indistinct state, not only on account of their prodigious distance, but because they are composed of vast cloud-masses of glowing gas.

Thus, infinite space must be represented as an immense void in the bosom of which are suspended archipelagoes of stars. These archipelagoes are themselves of infinite number, the stars which compose them can be counted by millions, and from one to the other the distance is incalculable. They are distributed in space in every direction, in every sense, follow- ing every imaginable course, and themselves invested with every possible form, as we shall soon see.

One of the most remarkable and regular nebulae, and the one that may at the same time serve best for illustrating the arguments which precede, is the nebula in the Centaur. We shall study further on the aspect of the constellations and the most simple method of finding celestial objects most worthy of our attention. This nebula is presented under the follow- ing aspect in the field of a good telescope.

With the naked eye it is with difficulty distinguished as a point of faint light ; in the telescope it is seen as a pro- digious number of stars strongly condensed toward*: tliR

22 Marvels of the Heavens,

centre. This condensation is a manifest proof that the cluster of stars is not only circular, but also spherical. One instant . of attention suffices indeed to show that if we look at a sphere of stars at a distance, the visual ray will pass through less if it look at the edges of the sphere than if it look at the centre, and will meet with fewer stars on its passage towards the borders than towards the centre. In proportion as this

Fig. 2. — Cluster in the Centaur.

visual ray gets nearer the centre its part comprised in the sphere will become longer, and the number of stars which it will meet goes on increasing. The maximum will be at the very centre. It was this optical effect which induced the belief in a condensation of nebulous matter. Halley dis- covered this cluster in 1G79, whilst he was working at the catalogue of objects visible in the Southern heavens.

General Arrangement of the Universe. 23

The limits of this cluster are not so clearly defined as in those which have particularly received the name of globular. Fig. 3 represents some types chosen from the latter.

Fig. 3 — Glubular C usti rs.

Of these star-clusters the first are certainly spherical ; others elongated, the thickness of which we see gradually diminished. These aue probably also circular, but flattened

24

Marvels of the Heavens.

in the form of lenses ; instead of being presented to ns in front they are seen edgeways.

At the sight of these globular masses one may ask with Arago, What is the number of stars contained in some of

General Arrangement of the Universe.

25

these clusters. The astronomer himself replied to his question. It would be impossible to count in detail and accurately the total number of stars of which certain globular nebulas are

	^--^ii-v ■<,
v ., .	- " •%# -•"■ . i
! %0	1 ■

composed ; but one may be able to arrive at limits. In cal- culating the angular space of the stars situated near the edges, that is to say, in the region where they do not project on

26 Marvels of the Heavens.

each other, and comparing them with the total diameter of the group, it is certain that a nebula, whose apparent super- ficial extent is scarcely equal to the tenth of that of the lunar

Fig. 6.— Nebula in the Lion.

disc, does not contain less than 20,000 stars ; this is the minimum. The dynamic conditions proper to insure the indefinite preservation of a similar multitude of stars, does

General Arrangement of the Universe 27

not seem easy to imagine, adds the celebrated astronomer. Supposing the system at rest, the stars in time will fall on each other. Giving it a rotatory movement round a single axis, shocks will inevitably take place. After all, is it certain a priori that the globular systems of stars must be preserved indefinitely in the state in which we now see them ?

The examination of changes which have taken place in other systems led to the belief, on the contrary, that there is nothing infinitely stable there, and that movement governs these clusters of suns, as wrell as it governs each of the stars, and each of the little worlds which revolve round them.

The most regular nebulas are not the most curious ; not- withstanding, the aspect of some of them leaves a certain wonder in the mind. There are star-clusters which, instead of being condensed in an immense globe, are distributed in a crown, presenting the appearance of a circular or oval nebula, but hollow at its centre. Two types of this kind are represented in figs. 5 and 6.

The first is the perforated nebula of Lyra ; the second is that of Andromeda. In the one, the magnificent telescope of Lord Rosse shows dazzling borders of stars close together, and luminous fringes notching the outer edge ; in the other, two suns, symmetrically placed on one side and the other of the ellipse, appear destined to the government of this system in its passage through space. Perforated nebulae, says A. de Hum- boldt, are one of the rarest curiosities. That of Lyra is the most celebrated; it was discovered in 1779, at Toulouse, by Arquier, at the time when the comet pointed out by Bode approached the region that it occupied. It is about the apparent size of the disc of Jupiter, and forms an ellipse, its two diameters being in the ratio of four to five. The interior of the ring is not dark, but slightly luminous. The hollow space is, however, of a very deep black in the beautiful per- forated nebulas of the Southern hemisphere. All are probably star-clusters in form of rings.

The interesting nebula sketched on the foregoing page

28 Marvels of the Heavens,

will serve ns as a transition between the regular and irregular nebulas ; it is the elliptic annular cluster in the Lion. It appears to possess a central nucleus of great condensation. This nucleus is enveloped with concentric spheres, more or less filled with stars, separated from each other by spaces, and these envelopes succeed each other along a great axis, getting farther from the centra diminishing in extent equally on all sides, as far as the pon*t where they fade away in a cone.

w

CLUSTERS AND NEBULA — (com ihukdj

' When night, with wings of starry gloom, 0 ershadows all the earth and skies, Like some dark, heauteous bird, whose plume Is sparkling with unnumber'd eyes — That sacred gloom, those fires divine, So grand, so countless, Lord, are Thine ! '

Moore.

In proportion as the magnifying power of telescopes is increased, the contour of these star-clusters, like their in- terior aspect, presents itself under a more and more irregular form. Such of these objects which formerly appeared purely circular or elliptical, have since showed great irregularity in their form as well as in the degree of their luminosity. In the place where pale and whitish clouds gave out a calm and uniform light, the giant eye of the telescope has discovered alternately dark and luminous regions. The figures we are about to give all tend to support this remark ; others confirm it in a still more striking manner. For instance, there is in the zodiacal constellation of the -Bull a uniform and oval nebula, which does not present the least singularity in instru- ments of small power; but when Lord Eosse pointed his telescope to it for the first time, he could not resist imme- diately giving it the singular name of the Crab nebula, which its form alone suggested. The ellipse was changed into a fish ; the antennae, claws, and tail were depicted on the black sky by a white outline, formed by long trains of stars.

30 Marvels of the Heavens.

There are irregular clusters and nebulae of every possible shape, and of the thousands which have been already observed, described, and sketched, no two of them have been found to

Fig. 7.— Crab Cluster in the Bull.

resemble each other. They take the most extraordinary forms. Some present the aspect of real comets ; the nucleus is accompanied with a large tail and long luminous train :

Clusters and Nebulae. 31

these are in the Unicorn, the River Eridai.us, and the Great Bear ; and especially that in the Ship Argo, in which is again found the classical type of the most regular comets. Others, like that in Orion, most celebrated by the study which has distinguished it, or like that of the Magellanic Clouds and in the Ship (/;), appear like immense vaporous clouds tossed about by some rough winds, pierced with deep rents and broken in jagged portions. Another, again

Fig. 8.— The Ship Argo.

(that in the Fox), resembles the dumb-bells which gymnasts lift up to exercise the power of the arms ; that in Sobieski's Crown describes on the page of heaven the last capital of the Greek alphabet, n.

Other nebulas are grouped together, as if two or three of these vast systems had united their destinies. Many are double ; we see two spherical masses united by the diffused glow which envelopes them, or they may be separated by a

32

Marvels of the Heavens.

slight angular distance, or sometimes even enclosed in lumi- nous concentric strata like two eggs of snow in the midst of a nest of light. Again, elsewhere, in the Magellanic Clouds

in the Southern hemisphere, we see four circular nebulae ar- ranged at the four angles of a lozenge, itself illuminated with fine star-dust ; at one of the extreme angles, the nebula is itself divided into four globes, so that in reality we have before us an

Clusters and Nebulae.

33

immense cluster of stars, of which the extreme limits present seven principal condensations. But this is not all. Not only do these distant systems, some of them peopled with myriads

of suns, take the most varied forms, not only do they present a diversity of aspect greater than it is possible to imagine ; but some of them also unfold to the astonished eye which contemplates them varied shades and real colours. One is

34 Marvels of the Heavens,

}f a beautiful indigo blue ; another is rose-coloured at its centre with a white border, another again emits magnificent sky-blue rays. This colouring is produced by the actual colour of the stars which compose it.* Others have been seen whose luminous intensity has perceptibly varied ; the bright- ness of one of them has faded to such a degree as to be rendered completely invisible.

It is difficult to describe the impression which the sight of these distant universes makes on the mind when one sees them through the wonderful telescopes of modern times. The rays of light which reach us from so far place us for the time in communication with these strange creations, and the senti- ment of terrestrial life hushed in the silence of night seems governed by the influence which celestial contemplation so easily exercises on the captivated soul. Earthly things- lose their value, and one joins willingly with the voice of the poet of the Irish Melodies : —

' There's nothing bright but heaven, And false the light on glory's plume,

As fading hues of even ; And Love and Hope and Beauty's bloom, Are blossoms gathered for the tomb ;

There's nothing bright but heaven.1

One feels that, in spite of the unfathomable distance which separates our abode from these far-off dwellings, there are there luminous foci and centres of movement : it is not a void, it is not a desert ; it is ' something,' and this something suffices to attract our attention and awaken our reverie. An indefinable impression is communicated to us by the stellar rays which descend silently from unexplored abysses ; one feels it without analysing it, and the traces of it remain ineffaceable, like those felt by a traveller when he steps on strange lands, and sees new sides above his head. This is described by the illus-

* This remark applies to the clusters only. In the nebulae the colours are due to another cause. — Ts

Fig. 11.— Spiral Nebula in the Constellation of the Hunting Dogs.

Nebulce. 37

trious author of ' Cosmos,' when he presents the Magellanic Clouds, vast nebulas close to the Southern pole, as a unique object in the world of celestial phenomena. ' The magnificent zones of the Southern heavens comprised between the parallels from fifty and eighty degrees, are the richest in nebulous stars and irreducible nebulous clusters. Of the two Magel- lanic Clouds which lie near the Southern pole, this pole so poor in stars that it might be called a waste country, the largest especially appears, according to recent researches, to be a wonderful agglomeration of spherical clusters of large and small stars, and irreducible nebulas, whose general brightness lights up the field of sight and forms the background of the picture. The aspect of these Clouds, the brilliant constella- tion of the Ship Argo, the Milky Way, which extends between the Scorpion, Centaur and Cross, and the picturesque aspect of the whole Southern sky, have produced on my mind an ineffaceable impression.' Nevertheless, the most mag- nificent and eloquent aspect of the nebulae has not yet been revealed to us by those which precede. To form an idea of the importance of these objects, and to appreciate their value, from the space which they occupy, also from the time which has been necessary for their formation, we must see the splendid spiral nebulas which the powerful telescope at Parsonstown unveils to us, and which in ordinary instruments only present appearances similar to those we have already noticed.

Lord Rosse, indeed, was the first to discover that the vast systems of suns were clustered, not only simply round a centre of condensation, not only in masses more or less regular, but according to a distribution which reveals the existence of gigantic forces in action among them. He observed some immense agglomerations of which the composing stars were distributed in long lines in a general system of spiral curves.

From the principal centre springs a multitude of luminous spirals, formed of a numberless quantity of suns or nebulous masses, shaping the resplendent nucleus, whence they issue to be lost in the distance, imperceptibly parting with their bright-

38 Marvels of the Heavens.

less, and dying away as trains of phosphorescent vapours. A secondary nucleus brings up on one side the extremities of the longest spirals. There are splendid bands of constellated 'ight, terminated with two rounded nodes. This rich spiral .iebula belongs to the constellation of the Hunting Dogs Before the discovery due to the powerful telescope which removed the veil with which it was enveloped, the best instruments only showed it as a single jing, one half of its contour surrounding a very bright globular nebula at its centre. Beyond the ring was noticed a second very small round nebula. Never was change of form more manifested between the aspects revealed by telescopes of different powers. To imagine the myriads of centuries necessary to the forma- tion of these immense systems would be a vain undertaking. It is with slowness that nature accomplishes its most tremendous operations. In order that cosmical matter or the prodigious assemblage of so many stars could be distributed according to the curves revealed by the telescope, and winding round each other in gigantic spirals under the governing action of the combined attraction of all parts which compose this universe, it would require an incalculable series of accumulated years to pass away. Here especially it is truth to say that the luminous rays which descend from those distant creations are to us the most ancient testimony of the existence of matter.

The spiral nebula of the Hunting Dogs is not the only one of this form. In the constellation of the Virgin, Lion, and Pegasus, we also admire similar systems. That in the Virgin, situated in the central ring of this figure, is presented under the aspect of the ' wheels ' that we see in fireworks ; from the luminous centre white trains of light wind round, all guided and curved in the same direction ; dark spaces separate them and give more clearness to the sketching of their direction. That in the Lion presents a series of oval concentric zones enveloping the centre, also more luminous ; numerous stars shine out in the centre. The spiral nebula of Pegasus,

Nebulce. 39

marked with a beautiful star at its central point, is circular, and compose.d of circles alternately dark and luminous ; on one side the circumference is cut by a tangent, a wide line of light longer than the nebula itself, to which this appears to

Fig. 12.— Spiral Nebula in the Virgin

be attached, like the little silken nests of insects on branches. In writing these lines. I am reminded of the year 1702, in which a maker of systems wrote a large book proving that the universe is a large spiral. According to him, God was

40 Marvels of the Heavens.

placed at the centre of the heavens ; from this centre He would communicate with all other created beings by an infinity of spiral lines directed towards the circumference. Sun and worlds, bodies and spirits, all would move in a spiral. If this singular author were again born in our day, with what delight would he seize our spiral nebulae to illus- trate his thesis.

Nebulae are not uniformly spread in all regions of the sky. On the starry sphere vast localities may be observed where no nebula is visible, whilst, in other parts, they appear really heaped up.

The richest region of the heavens is in the following group of constellations, which will soon be recognised : the Great Bear, Cassiopea, Berenice's Hair, the Virgin. In the zodiacal region, near the Virgin, in an hour may be seen more than three hundred nebulae ; whilst, in the opposite region, a hundred would not be met with. The spaces which precede or follow nebulae contain few stars. Herschel found this rule constant — so constant, in fact, that each time during a certain period no star was brought in the field of his immovable telescope by the movement of the heavens, he used to say to his secretary who assisted him, ' Get ready to write, nebulae are coming.'

From this fact, namely, that the spaces poorest in stars are near the richest nebulae, and from the other, that stars are generally more condensed towards the centre of nebulae, follows a confirmation of what we said before on the incessant work of many centuries which would be required to elaborate these systems. There is nothing astonishing that these powerful unions were formed, either at the expense of the surrounding cosmical matter, destined to be condensed in stars, or at the expense of the stars themselves, and that the spaces which surround them resemble vast deserts or regions laid waste.

At the sight of the pale nebulae which sprinkle the expanse, the soul feels itself attracted, as at the edge of those abysses whose unknown depth produces giddiness. To the

Nebulce, 41

greatness of the spectacle succeeds a dearer sentiment, a sentiment of affection for these mysterious beauties, and one understands how much they exceed the most precious riches-, of earth.

' Ye stars ! which are the poetry of heaven ! If in your bright leaves we would read the fate Of men and empires, — 'tis to he forgiven, That, in our aspirations to be great, Our destinies o'erleap their mortal state, And claim a kindred with you ; for ye are A beauty and a mystery, and create In us such love and reverence from afar, That fortune, fame, power, life, have named themselves a star

All heaven and earth are still — though not in sleep,

But breathless, as we grow when feeling most ;

And silent, as we stand in thoughts too deep:

All heaven and earth are still. From the high host

Of stars, to the lulled lake and mountain-coast,

All is concentred in a life intense,

When not a beam, nor air, nor leaf is lost,

But hath a part of being, and a sense

Of that which is of all Creator and defence.

Then stirs the feeling infinite, so felt- In solitude, when we are least alone ; A truth, which through our being then doth melt, And purifies from self; it is a tone, The soul and source of music, which makes knows Eternal harmony, and sheds a charm Like to the fabled Cytherea's zone, Binding all things with beauty ; — 'twould disarm The spectre Death, had ne substantial power to tiar^

Not vainly did the early Persian make His altar the high places, and the peak Of earth, o'ergazing mountains, and thus take

42 Marvels of the Heavens.

A fit and unwalled temple, there to seek The Spirit, in whose honour shrines are weak, Upreared of human hands. Come, and compare Columns and idol-dweliings, Goth or Greek, With nature's realms of worshio, earth and air, Nor fix on fond abodes to cir^uaiscribe thy prayer I '

• Ckiidfi IJarot*

43

VI

THE MILKY WAY.

O nuit majestueuse, arche immense et pr fond^, Ou Ton entrevoit Dieu comme le fond sousPondt? Ou taut d'astres en feux portant ecrit son nom, Vont de ce nom splendide eclairer 1 horizon, Et jusqu'aux infinis ou leur courbe e*t lancee, Porter ses yeux, sa main, son ombre et sa pensee ! Et vous vents palpitant la nuit sous ces hauts lieux Qui cavessez la terre et parfumez les cieux ! Mysteres de la nuit, que l'ange seul contemple, Cette heure aussi pour moi leve. un ricleau du temple Lamaetine, Jocelyn.

We have seen that the universe is formed of clusters and nebuLe, spread in the immensity of space, at every imaginable depth and in every possible direction.* But then, if there are only nebulae in space, and if no heavenly body is isolated from these clusters, our Earth, then, forms part of a nebula. The inhabitant of the terrestrial globe, then, finds himself also in the bosom of one of those immense clusters of stars which constitute the archipelagoes of the celestial ocean. And we do not, therefore, live, as appearances lead us to suppose, beyond this starry creation which shines over our heads. In a word, if all the celestial bodies are united in groups, the Earth, then, also belongs to a group of stars, and a cluster.

Yes. The Earth, like all the stars, forms part of a cluster ! It is not isolated in the deserts of the infinite ; it is not an ex- ception to the general law. The Earth, like the planets which are near it, belongs to the Sun. This Sun represents them in the universal numbering of the stars, for neither Earth nor

* Let us now add that a recent discovery has proved several of the nebulae to be composed of masses of incandescent gas. — Te.

44 Marvels of the Heavens.

planets count in the number of these splendours, and this Sun is one of the stars composing an immense nebula.

The Sun is but a star ! This assertion seems astonishing at first sight, on account of the illusions produced by the senses. The torch of our light, the focus of heat, the ruler of ter- restrial life, appears to us under the legitimate prestige of its own power, and we bow to it as the prince of stars, as the first among the great ones of the heavens. And for us, indeed, it supremely deserves these titles, and all those which our just knowledge pleases to attribute to it. But if we consider it superior to the stars, if we find it more important, more magnificent, and more necessary, it is only because we are nearer to it, because in reality we are its tenants, its subjects, and that, contrary to that which happens on Earth, we recognise with delight the superiority of our master in the celestial realm. Belonging to him, we live at his expense, real parasites, and without him we should fall at once into the shades of death. To thank him and recognise his power is only just. Nevertheless, to judge things from an absolute point of view, we must rise above any particular dependence which may oppose the justice of our judgment, like him wTho, placed in the interior of an edifice and wishing to ascertain the rank of this edifice in the town, goes to a distance from it, and, placing himself on high ground, compares the various edifices with each other. We must, in the same way, put aside solar rule, and transport ourselves in spirit to a distant point in space, whence we should be able to determine the rank occupied by our Sun in the sidereal world.

Now, on getting further from the Sun towards any point in space, we shall see the Sun diminish in size and lose the importance which appeared to be his privilege. When we reach the limits of his system, he will then only present the aspect of a large star. On getting still further away, we shall see it descend to a simple star. Lastly, if we go towards any star in the heavens and continue to watch the decrease of the Sun which sinks behind us in the depths of space, it will

The Milky Way. 45

become a small star soon lost in the multitude of others ; the one we are approaching will lose, on the contrary, its small aspect, will increase, shine out, and get larger in proportion as we approach it, and will become a real sun, not less important than ours by its luminous and calorific power and by the gifts it distributes to the planets of its domain.

Passing beyond this new sun and continuing our path, we shall behold an analogous transformation of other stars into suns ; all those towards which we shall pass successively will appear to us under this aspect, thus showing that they shine with their own light and are so many planetary foci. Lastly, when we shall have crossed these starry plains, we shall reach shores where the suns are more scarce, and soon, a desert void of stars.

To the thousand millions and thousand millions of miles we have just traversed, let us again add a certain quantity of thousands of millions, and we shall soon arrive at a favourable point for estimating the absolute rank of our Sun. Let us then suppose that we at last reach the point from which we see the suns constituting our cluster, and then returning by the way we came, wTe should find out what place our Sun occupies in the army of stars that we have left behind us.

It is there only that we can judge well of things. Now, this is what appears to us. All the stars which people our starry nights are enclosed in a narrow space, and we notice — now that we are beyond them — that they form a cluster of small bright points, and that they resemble an isle of lights suspended in space. In a word — and this is the point to which we wished to arrive — they form a cluster. This cluster is isolated ; its limits are clearly enough defined, and no group, no star, shines in the space which surrounds it. It is marked out in the darkness in the following page (fig. 13).

This is the nebula in which we live ; this is the abode of, our solar world. In wrhat port of it are we? The question is at least curious, and. from the spot, where we are placed to observe the star-cluster of which we form part under its true

46

Marvels of the Heavens.

aspect, the best instruments would not succeed in distin- guishing our little Sun. But it is not always necessary to see - people in order to guess where they are. This is why we are able to travel towards the centre of the nebula, and, not far from the line which separates the zone into two layers, to ob- serve a little point. This point is the place occupied by our Sun. The Earth and planets are with him ; but, since it is impossible to distinguish the Sun in the midst of this multitude, a fortiori, the utter impossibility of perceiving the slightest vestige of the existence of our planetary system will be manifest.

Fig. 13.— The Milky Way.

If wTe live thus in the middle region of a rich nebula, how7 is it, it may be asked by curious minds, how is it that we cannot distinguish it, and that our clear nights present around us a sky purely and splendidly starry? Is it then necessary to go away so many thousand millions of leagues from the Earth to know where it is placed ? And if that is necessary, how has it been known ?

No : this is not necessary, as the position is known. From the surface of our sphere we observe the sky, and we see that all around us a large nebulous circle envelopes our globe. We are ourselves near the centre of this circle, and

The Milky Way. 47

each night displays over our heads a whitish band of dense stars continually surrounding us. This collection of stars, it has already been guessed, is the Milky Way.

The Milky Way, this wide irregular ribbon of stellar clouds which crosses the sky in all its width, is indeed nothing more than the greatest length of this immense lens of stars to which we belong. If the whole sky does not appear nebulous in every direction, it is precisely because the nebula to which we belong is not spherical, but of a lenticular form, and that in the thickness of the lens there is less depth and fewer stars than in the direction of the diameter. From the spot on which we are placed, if our sight pass through the greatest length it meets stars on stars indefinitely, because there is an immense expanse from the point where we are to the edges of the flattened nebula. But if our sight turn aside from the equatorial plane towards the sides, it meets with fewer stars as it gets further distant, and on reaching the polar diameter, scarcely any more will be met with. There are thirty times less stars in these regions than in those near the equatorial plane of the cluster.

All the stars which sparkle in the sky during a dark night belong to a single cluster, to a single nebula, the Milky Way marking its longitudinal direction. The stars are not isolated in an absolute manner, at random, in the deserts of space ; they form part of a whole ; the Sun which lights us is one of them ; and they are counted by millions in a gigantic group, analogous to the distant clusters of which we have already spoken. Instead of only seeing a diffused glimmer, an indistinct light in the Milky Way, the telescope separates the stars which compose it and shows that it is formed of an innumerable multitude of stars very irregularly connected.

The idea which we must form of the Milky Way is then very different from that which appearances present to us and from that with which the ancients contented themselves. From the beginning of ages, from the first observations of an elementary astronomy, this semi -luminous train which crosses

48 Marvels of the Heavens.

the sky was noticed, and the ruling mythology adorned it with images.

A Scotch poet of the sixteenth century, George Buchanan, described the history of the singular opinions entertained of the Milky Way ; at the same time he rose above it to the true cause of this heavenly sight.

' Can I pass thee in silence ? Thou whom ancient poet? have celebrated so greatly in their songs ! Thou who dividest the heavens with thy wide belt, and who formest one of its most beautiful ornaments ! Thou shinest in the bosom of night, visible to the whole universe, attracting the eyes of mortals. Thou spreadest thy soft light each time that the cloudless atmosphere permits us to see the heavenly vault with clearness. That brilliant whiteness which causeth thee to be so easily noticed has given thee the name of the Milky Way, either (if fable has not imposed on the ancient poets) because ' some drops of milk fell from Juno's bosom and flowed among the stars, tracing on the azure of the heavens this belt remarkable for its whiteness, or, according to others, because it is the path which leads to the dwelling of the gods, and to the palace of the god of thunder. There are those who believe that it is the home which the shades of happy souls inhabit ; that there, free from all work, free from all trouble, they live like gods in eternal bliss. Others persist that the pole still preserves the traces of the fire caused by Phaeton, when Phoebus' car, thrown from its path by this new conductor, left to the prey of the flames the heavenly abodes and omitted to embrace the universe. . There are some who pretend that, when God created the world and gathered the different parts together, and united its immense sides, the ends of the heavens welding themselves together, left a seam between them, and formed a con- tinual scar, which marks the point of union of all these parts. But those, who busy themselves with seeking the secret causes of heavenly phenomena, believe that this band is produced by a mass of contiguous little stars, whose united lights form this luminous whiteness, similar to that which twilight produces, or to that feeble light which the stars retain when they fade on the approach of Phoebus.'

The Milky Way. 49

These fantasies of imagination, authorised by old fables, were far from the truth ; and in this case, as heretofore, truth is more beautiful, greater, and more admirable than fiction. From the day when the first astronomical glasses dis- tinguished the stars whose cluster forms the glimmer of this zone, astronomers directed their attention to its constitution and structure. William Herschel, with the powerful tele- scope made with his own hands, resolved, towards the end of the last century, to count the stars comprised in this zone : he addressed himself to his task and divided his work into portions. His long perseverance was crowned with success. By a careful comparison of the parts wThere the condensation of stars attains its maximum with those where it attains its minimum, and by an examination of the extent occupied by these immense rings, the great observer found that the Milky Way did not enclose less than eighteen millions of stars !

Eighteen millions of stars in the equatorial stratum of the lenticular nebula to which we belong : this is not the total number of which it is composed, as this does not refer to the lateral portions of this gigantic mass, and all the stars of the heavens situated on one side and on the other of the plane of greatest condensation are not included in this enumera- tion. We shall see further on, in the chapter devoted to the study of the stars, that the total number of the members of this populous tribe is much greater still than eighteen millions. What is the real extent occupied by this collection of suns ? The number of stars which compose it, and the relative distances from each other, comprises for this extent a number which the mind cannot well receive without being prepared for it, a number which it cannot appreciate without making great efforts to grapple it. I will not give the dis- tance in leagues, because an immense continuation of leagues exceeds the limits of even the vision of the mind ; it is better to take the measure used constantly for astronomical units. Now, the extent of the Milky Way, at its greatest length, would be measured by a ray of light which, travelling 186,000

50 Marvels of the Heavens,

miles per second, would travel in a straight line and with- out stopping for fifteen thousand years.

Thus, as we are ourselves near the centre of this nebula, when in the field of a powerful telescope we observe the little distant stars situated in the depths of the Milky Way, our retina receives the impression of a luminous ray, which started seven or eight thousand years ago from a sun analogous to ours and forming part of the same group.

If such be the extent of the nebula of which we are an infinitesimal constituent part, are not the other nebulae scattered in space also as rich and vast; or rather is our nation privileged, and does it exceed the others in richness or in extent ?

There is no reason to stop at this last idea, as a remnant of vanity would be perhaps able still to suggest to us, to make up a little for the mediocrity of the natural rank which we hold. The Milky Way is not unique ; many of the nebulae of the universe are so many Milky Ways, more or less similar to our own. Some may be less vast ; others may possibly be vaster still, seeing that, in the domain of the infinite, space goes for nothing. It is best for us, then, to take the middle course, and to think that the pale and diffused nebulae which seem to tremble in the distance in unfathomable immensities, are Milky Ways peopled with as many suns as our own. But then, as they appear so small to us, they must necessarily be distant from us. More distant, indeed, for if we find oat at what distance we must remove our Milky Way in order to reduce it to the limit of a medium nebula, we find that we must remove it to 334 times its length, a distance which our agile messenger, a ray of light, takes a little more than five millions of years to accomplish. Such is the distance which may separate the gigantic clusters of suns, with which the sidereal universe is composed, and which hover in space, suspended at all depths of unfathomable immensity from each other. Contemplating these wonderful splendours we can understand that to poets they would be a

The Milky Way. 51

subject of ecstasy, and we repeat with emotion the beautiful thoughts thoy have inspired :

' Oh, thou beautiful And unimaginable ether ! and Ye multiplying masses of increased And still-increasing lights ! What are ye ? What Is this blue wilderness of interminable Air, where ye roll along, as I have seen The leaves along the limpid streams of Eden ? Is your course measured for ye ? Or do ye Sweep on in your unbounded revelry Through an aerial universe of endless Expansion — at which my soul aches to think — Intoxicated with eternity ? Oh, God ! oh, Gods ! or whatsoe'er ye are ! How beautiful ye are ! How beautiful Your works, or accidents, or whatsoe'er They may be ! Let mo die, as atoms die (If that they die), or know ye in your might And knowledge ! My thoughts are not in this hour Unworthy what I see, though my dust is ; Spirit ! let me expire, or see them nearer.' •

* Lord Byron, Cain.

BOOK II.

55

THE SIDEREAL WORLD.

1 Un monde est assoupi sous la voute des cieux, Mais sous la voute meme ou s'elevent mes yeux, Que de mondes nouveaux, que de soleils sans nombre Trahis par leur splendeur etincellent dans l'ombre ! Les signes epuises s'usent a les compter, Et Tame infatiga'ble est lasse d'y inonter ! ... La l'an ti que Orion, des nuits percant les voiles, Dont Job a le premier nomme les sept etoiles ; Le Navire fendant l'efher silencieux, Le Bouvier dont le cbar se traine dans les cieux, La Lyre aux cordes d'or, le Cygne aux blanches ailes, Le Coursier qui du ciel tire des etincelles, La Balance inclinant son bsssin uncertain, Les blonds Cheveux livres au souffle du matin, Le Belier, le Taureau, l'Aigle, le Sagittaire, Tout ce que les pasteurs contemplaient sur la Terre,. Tout ce que les neros voilaient £temiser, Tout ce que les amants ont pu diviniser, Transporte dans le ciel par de touchants emblemes, N'a pu donner des noms a ces brillants systemes.'

Lamaetine,

According to what lias been previously stated, we in- habit the midst of a vast nebula ; its equatorial stratum, projecting itself on our sky, describes that cloudy zone known under the name of the Milky Way. Our Sun is one of the stars composing this gigantic cluster, and all the stars which sparkle during our silent nights form part, like him, of this same tribe. This is, properly speaking, our universe. The other nebulae may be considered by us as

56 Marvels of the Heavens.

other universes, foreign to this one, and which we have only contemplated in order to give us a more distinct notion of the grandeur of creation, but which we will henceforth leave in the unexplored immensity which they inhabit in the midst of space. Descending from the great to the small, proceeding from the whole to a part, we will now embrace less vast proportions ; we will pause at our sidereal universe, or, in other words, at the general description of the isle3 which constitute our celestial archipelago.

We will not yet speak of the nature of the stars, their distances, movements, or their particular history; before pursuing the reality, it will be well for us to make a digres- sion on appearances. We are, however, averse to appear- ances, and much prefer reality ; but there are some of which we cannot avoid speaking, seeing that they form in a certain way the surface of the things that must be searched into, and it is necessary to pass this surface before reaching the interior. But when we agree that such and such a phenomenon is only an appearance, there will be no harm in our studying it ; the important points to be understood and to avoid confusion.

The stars appear scattered at random in the heavens. In a fine starry night, when our sight rises to these heights, a great diversity in their brightness is noticed, and at the same time an apparent disorder in their general arrangement. This irregularity and the number of the stars have prevented the possibility of giving to each of them a particular name ; to recognise them and facilitate study, the heavenly sphere is divided into sections. The astronomy of the ancients, says Francoeur, was confined to a few rough distinctions ; they were at first contented to name the planets and most beautiful stars, and we have preserved this custom ; but when they wished to study more carefully, and wished to describe stars of less brilliancy, they could only follow a method, the imperfection of which they acknowledged. They were led like the naturalists who, to name the species of the three kingdoms, unite under a common name a certain number of

The Sidereal World. 51

creatures which they afterwards distinguish from each other by a qualification. Astronomers have united the stars in different groups, on which they have drawn an animal or fabulous being. To these groups, or constellations, they gave names from fables, history, or the animal kingdom. These denominations, consecrated by antiquity, are quite arbitrary ; and unless imagination itself creates images, as it sees pictures in the ever-changing contours of the clouds, we must not endeavour to find in the groups of stars anything which might recall the figure or imitate the image of the objects whose name the constellation bears. The necessity of being guided on the seas obliged man to choose in the heavens invariable signs by which he could direct his course, and this is the historical origin of the constellations.

The ancients formed representative maps of the heavens, and from the time of Hipparchus, the Greek astronomer, they were able to class the stars, distinguishing them according to their brightness, in the positions occupied by each of them on these figures.

It was necessary to fix on a method to find a particular star easily, in the midst of such a great number (four to five thousand) as is distinguished with the naked eye. The first origin of the constellations is unknown ; but it is ima- gined that they were established successively. The Centaur Chiron, Jason's preceptor, has the reputation of having first divided the heavens on the sphere of the Argonauts; but Job lived before the time, when the precedent is placed, and this prophet then spoke of Orion, the Pleiades, and Hyades, three thousand three hundred years ago. Homer also speaks of these constellations when describing Vulcan's shield : —

' And on its surface many a rare design Of curious art his practised skill had wrought, Thereon were figured earth, and sky, and sea, The ever-circling sun, and full-orb'd moon, And all the signs that crown the vault of heav'n ; Pleiads and Hyads, and Orion's might,

58 Marvels of the Heavens.

And Arctos, call'd the "Wain, who wheels on high

His circling course, and on Orion waits ;

Sole star that never bathes in th' ocean wave.' *

The same mythological divisions are used in the present day. Since the establishment of Christianity, there have been many efforts to reform this pagan system, and to replace it by Christian denominations. In the planisphere of Bede, St. Peter is substituted for the Ram, St. Andrew for the Bull, &c. From these attempts, no name escapes ; David's chariot, Solomon's seal, the three Magi kings, or Jacob's rod, &c, date the highest. Later still a German proposed to give to the twelve signs of the Zodiac the heraldry of the twelve most illustrious houses of Europe. These singular efforts remained sterile, and the mythological reign has continued until the present day.

As great diversity has been noticed in the brightness of stars, in order to facilitate their indication, they have been classed in order of magnitude. This word 'magnitude' is improper, seeing that it has no relation to the dimensions of the stars, these dimensions being still unknown to us ; it dates from a period when it was believed that the brightest stars were the largest, and this is the origin of the de- nomination ; but it is important to know that this is not its real sense. It simply corresponds to the apparent brightness of the stars. Thus, stars of the first magnitude are those which shine with the greatest brightness in dark nights; those of the second magnitude shine less, &c. Now, this apparent brightness belongs both to the real size of the star, its intrinsic light, and its distance from the Earth ; conse- quently, it only possesses an essentially relative meaning. Nevertheless, it may be said generally that the brightest stars are nearest, that those whose pale glimmer is scarcely distinguished in the field of the telescope are more distant.

Thus, when we shall speak of the magnitude of stars, it is

* Homer's Iliad.

The Sidereal World. 59

to be understood that we refer simply to their apparent brightness ; this brightness greatly facilitates the means of distinguishing them among the constellations. There is now another fact which is not less important to consider as relative, and not as absolute ; this is the arrangement of the stars or forms of the constellations. We know, already, that the sky is not a concave sphere in which bright nails are fast- ened, and that there is no kind of vault — only immense, infinite void surrounding the Earth on all parts and in every direction. We know, also, that the stars, suns in space, are scattered at every distance in the vast immensity. When, then, we notice two stars close together in the sky, their apparent proximity does not in any way prove their real proximity : they may be very distant from each other, in the direction of vision, at a distance equal to or greater than that which separates us from the nearest one. In a similar way, when four, or five, or more stars are united in the same group, this does not imply that these stars, forming the same constellation, are on the same plane and at an equal distance from the Earth. By no means. Dispersed at all depths of space, all around the terrestrial atom, the arrangement which they display to our eyes is only an appearance caused by the position of the Earth with regard to them. This is purely a matter of perspective. When we find ourselves during the night in the midst of a large, open space (for instance, the Place de la Concorde) in which numerous gas- lights are dispersed, it is difficult for us to distinguish, at a certain distance, the most remote lights from those which are less so : they all appear to be projected on the dark ground ; moreover, their general arrangement depends purely on oui point of view, and varies according as we ourselves walk away or across. This simple comparison may make ua understand why the stars, lights in the dark space, do not reveal to us the distances which may really separate them, and why their arrangement on the apparent vault of the sky depends only on the spot where we place ourselves to ex-

60 Marvels of the Heavens.

amine them. On quitting the Earth's surface and trans- porting ourselves to a spot sufficiently distant, we should witness, in the apparent arrangement of the stars, a varia- tion as much greater as our station of observation would be more distant from our previous one. For this it would be necessary to transport ourselves, not only to the last planets of our system, but beyond this system entirely, and to go to distances at least equal to those of the nearest stars. Indeed, from Neptune, the last planet of our system, the stars are seen in the same arrangement as from here. The change is only seen in quitting one star for another. One moment's reflection suffices to convince us of this fact, and to relieve us from further explanation on the subject.

These illusions once appreciated at their right value, we may, without fear, begin the description of the figures with which old fables have constellated the spheres. The knowledge of the constellations is necessary for the obser- vation of the heavens and for researches which love of science or curiosity may inspire ; without it, one finds one- self in an unknown country without any geography or pos- sibility of discovering our whereabouts. Let us, then, form the geography of the heavens. The innumerable figures of animals, men, or objects, with which the sphere is adorned, will not, however, be drawn here, seeing that they would only serve to confuse the mind with imaginary lines. Formerly they printed celestial atlases, where the figures were represented with exquisite care, so much so, indeed, that they ended by forgetting the stars, and the sky was nothing more than a menagerie. In spite of the interest of the images, I will not follow this example. I will only give further on, on a special map, the drawing of the constella- tions visible in our hemisphere. At present, let us see how to direct our course for reading correctly the great book of the heavens.

There is one constellation known to every one; for greater simplicity we will begin with it, as it will serve us

The Sidereal World. 61

as a starting-point to go towards the others, and as a sign to find its companions. This constellation is the Great Bear, which has also been called David's Chariot, or Charles's Wain ; which the ancients called Septem triones (whence came the word septentrion), or, again, Helix, Plaustrum ; which the Greeks addressed under the name of " Agytroc pzydXr), ikt%n, &c, which the Arabs called A Idebb al Akbar, and the Chinese, three thousand years ago, addressed as the Tcheou-pey, the god of the north. Thus it can boast of a high celebrity. If, however, in spite of its universal noto- riety, some have not yet had occasion to make its acquaint- ance, the following is the sign by which it may always be recognised. Turn towards the north, that is to say, opposite the spot where the Sun is at noon. Whatever may be the season of the year, the day of the month, or hour of the night, you will always see there a large constellation formed of seven stars, four of which are quadrilateral, and at an angle with the side ; the whole arranged like this :

Fig. 14. — Constellation of the Great Bear.

Have you not all seen it ? It never sets. Night and day it watches above the northern horizon, turning slowly in four-and-twenty hours around a star of which we shall speak presently. In the figure of the Great Bear, the three stars of the extremity form the tail, and the quadrilateral forms the body. In the Chariot the four stars form the

62 Marvels of ike Heavens.

wheels, and the three the car. Above the second between these latter, good sights distinguish a very small star called Alcor, which is also called the Cavalier. The Arabs called it Saidak, which means the proof, because they used it to test a good eye. Greek letters are used to denote each star ; they are the first of the alphabet ; a and 6 mark the two first stars, y and d the two others, s, £. »j, the three of the car ; Arab names have also been given to them, but I shall pass over them in silence, as they are not generally used.

This brilliant septentrional constellation, composed (with the exception of £*) of stars of the second magnitude, has received from olden times the gift of captivating the attention of observers, and personating the stars of the north. Many poets have sung its praises ; we will only repeat in prose one, — the words being worthy of the majesty of the heavens, — that of Ware, the American poet, —

' With what grand and majestic steps this northern con- stellation advances in its eternal circle, following its royal path amidst the stars with a slow and silent light ! Mighty creation, I worship thee ! I love to see thee wandering in the brilliant avenues like a splendid giant with a strong belt, — severe, inr defatigable, and resolute, whose feet never pause on their road. Other kingdoms abandon their nocturnal path and rest their wearied orbs under the waves ; but thou, thou never closest thy fiery eye, and never stoppest thy determined step. Forward, always forward ! whilst systems change, suns set, worlds sleep and awaken, thou followest thy endless way. The adjacent horizon endeavours to arrest thee, but in vain. A vigilant sen- tinel, thou never quittest thy secular path, but, without 'allowing thyself to be overtaken by sleep, thou preservest the fixed lights of the universe, always preventing the north from forgetting its place

' Seven stars people this bright kingdom ; the sight em- braces the whole ; their respective distances are not inferior tc

* This star is variable. Two hundred years ago it was not less brilliant than its companions.

The Sidereal World. 63

their distance from the Earth. And here again we see the tre- mendous distance between the celestial orbs. From the depths of the heavens, unexplored by the mind, the piercing rays dart through space, revealing to the senses numberless systems and worlds. Our sight must arm itself with the telescope, and ex- plore the heavens. The heavens are opened, a rain of sparkling fire falls on our heads, stars appear close together, are condensed in such far-off regions, that their rapid rays (more rapid than any other thing) have travelled for centuries in order to reach the Earth. Earth, Sun, and nearest constellations, what are you amidst this infinite immensity and the multitude of divine infinite works?'

These thoughts, inspired by scientific truth, are superior to those of ancient mythology. Without speaking of the name of Bear given to this constellation and the follow- ing one, not only by the Greeks and Latins, but again by other people who did not appear to have had any communi- cation with them, like the Iroquois who gave to them the same name,* we shall state that, generally, the Great and Little

* It is a remarkable fact, and one which may be used in the his- tory of ancient astronomy in particular, as in that of the origin of people in general, that groups of stars without any characteristic figure have been called by the same name by the most diverse people. The Indians and Chinese have the same zodiacal constellations as the Greeks, bearing the same etymological names, and distributed in the same direction. The northern constellations have received the name of Bears with the people of High Asia, Phoenicians, Arabs, Greeks, and Iroquois, although the square and the tail drawn by their arrange- ment do not recall in any way tne bears which have no tails. In America the name of the ' Jawbone of an Ox ' is applied to the Hyades placed in the head of the Bull. With the Arabs, the constellation of Andromeda is a chained woman ; with the Persians, Cassiopea is on a chair, and Hercules kneeling ; the seven stars which we name the ' Pleiades, the Indians called Chickens ; in India and Persia, Perseus bears a head : the Brahmins have sensibly the same zodiac as we have; the Milky Way of the Greeks is with the Chinese the Celestial Eiver, to the Copts the Stubble field, to the savages of North America the Path of Souls, and to the inhabitants of the French provinces the Path of St. John. Beside the rare connexion which would strictly explain these designations, these coincidences remain the objects of great mystery. They would be in favour of the unity of a primitive human stock.

64 Marvels of the Heavens,

Bear were considered as Callisto and her dog. Jupiter had a son by this nymph, the cow-herd (Bootes), of whom we shall speak further on ; he had them both placed in the sky. But the official wife of the king of gods, Madame Juno, as Virgil has said, was greatly incensed, and obtained from Thetis, the ruler of the waves, that these perfidious constellations should never bathe in the ocean. Thus their continued presence above the horizon is explained. Callisto, whose car fears the wave of Thetis, near the ice of the north shines out near her eon. The Dragon embraces them like an immense wave. According to others, the two Bears are nymphs who fed Jupiter on Mount Ida ; according to others, again, they represented the oxen of Icarus ; but these fabulous fancies do not interest us more than they ought to do, and now that we recognise the Great Bear we must make him useful in our celestial voyages among the stars in his neighbourhood and our uranographic researches generally.

Let us return to the figure before traced. If a straight line be carried through the two stars, marked a and j3, which form the extremity of the square, and prolonged beyond a to an extent equal to five times the distance from /3 to a, or, in other words, to an extent equal to the distance of a to the extremity of the tail ?j, a star less brilliant than the preceding ones is found, which forms the extremity of a figure like the Great Bear, but smaller and directed in a contrary direction. This is the Little Bear, or Little Chariot, also formed of seven stars. The star to which our line brings us, that which is at the extremity of the Bear's tail, or at the end of the shaft of the Chariot is the Pole Star.

The Pole Star has a certain renown, like all personages who distinguish themselves from others, because, among all the stars which twinkle in our starry nights, it remains im- movable in the heavens. At any moment of the year, day or night, if you observe the sky you will always find it occu- pying the same place. All the other stars, on the contrary.

The Sidereal World. 65

revolve round it every twenty-four hours, a hold for the centre of this immense whirlpool! The Pole-Star remains immovable over one pole of the world, whence it is used as a

I fixed point by navigators of the pathless ocean, as well as by travellers in an unexplored desert. Of the thousand facts which I could quote to show how many times the Pole-Star and its constellation, always visible in the north, have saved the lives of travellers lost' in dark- ness, I shall content myself with the following, in which Albert Montemont honours the star of the north.

On the 4th of April, 1799, the English General, Baird, then at war against Tippoo-Sa'ib, received orders to march in

Fig. 15. Great Bear, Little Bear, Pole Star.

the night, to observe a height on which it was supposed the enemy had placed an advanced post; Captain Lambton accompanied him as aide-de-camp. After having crossed this height several times, without meeting with any one, the General resolved to return to the camp, and he turned back, as it appeared to him, to the general quarters. But, as the night was light and the constellation of the Great Bear was near the meridian, Captain Lambton remarked, that, instead of returning south, as he must do to return to the camp, the division had advanced to the north, that is to say, towards the body of the enemy's army ; and he instantly made the General aware of this mistake. But this officer, who troubled himself very little about astronomy, replied that he knew

66 Marvels of the Heavens.

well enough what he was doing without consulting the stars. At the same instant, the detachments fell in with the enemy's advanced post. This surprise having confirmed the Captain's observation too well, they at first hastened to disperse the soldiers of the advanced post and then to turn back on their road. They procured a light, consulted a compass, and found, as the astronomical officer said laughingly, that the stars were right.

The immobility of the Polar Star at the north, and the movement of the entire heavens round it, are appearances caused by the movement of the Earth on its axis. We will give the evidence further on ; but, while we are visiting the country of the stars, we must not leave such a beautiful sight to descend to the Earth. Let us then c©ntinue our mode of surveying, and make ample acquaintance with the population of the starry heavens.

*7

II.

THE NORTHERN CONSTELLATIONS.

* Aux lieux ou rayonnent des clartes eternelles Les cieux sont toujours purs et les nuits toujours belles, Ou l'Euphrate roulant ses flots au loin couverts De l'ombrage fleuri de palmiers toujours verts, Voit de feux plus puissants la nature animee Prodiguer le cinname et la myrrhe embaumee, Le pasteur de Babel en gardant ses troupeaux Observa le premier les celestes flambeaux ; Et, la nuit, promenant ses tentes egarees, Osa du firmament diviser les contrees.'

CffiNEDOLLE.

Looking at the Pole Star, stationary in the midst of the northern region, we have the south behind ns, the east to the right, the west to the left. All the stars revolving round the Pole Star, from right to left, ought to be recognised according to their mutual relations rather than according to the cardinal points. On the other side of the Pole Star, relating to the Great Bear is another constellation easily recognised. If a line be brought to the pole, from the star in the middle (d), by prolonging this line to an equal extent, the figure of Cassiopea is crossed, which is formed of five stars of the third magnitude arranged somewhat like the slanting strokes of the letter M. The little star x, which ends the square, also gives it the form of a chair. This group takes every pos- sible position, going round the pole ; sometimes being above, sometimes below, sometimes to the left, and sometimes to the right : but it is always easy to find, seeing that, like the

68 Marvels of the Heavens.

preceding constellation, it never sets and is always opposite to the Great Bear. The Pole Star is the axle around which these two constellations revolve.

If we now draw, from the stars a and $ of the Great Bear, two lines joining the pole, and we prolong these lines beyond Oassiopea, they will lead to Pegasus, which is terminated on one side by a row of three stars similar to those of the Great Bear. These three stars belong to Andromeda, and themselves lead to another constellation,

Fig. 16. Cassiopea, Andromeda, Pegasus.

Perseus. The last star of the square of Pegasus is, as we have seen, a Andromedse ; the three others are called. y, Algenib, a, Markab, and (3, Scheat. To the north of j8 Andromedse is found, near a little star, v, the oblong nebula which has been compared to the light of a candle seen through a horn plate, the first nebula of which mention is made in the annals of astronomy. In Perseus, a, the most brilliant star in the prolongation of the three principal stars of Andromeda, is seen between two others less brilliant, which with it forms a concave arc very easily distinguished.

The Northern Constellations. 69

This arc will now serve us as a new starting-point. By continuing it from 8, a very brilliant star of the first magni- tude, is met with ; this is the Capella. Forming a right angle with this prolongation to the south, we arrive at the Pleiades, a brilliant cluster of stars. On one side is a varia- ble star, Algol, or the Head of Medusa.

The star Algol or (3 Persei, which is seen above a, belongs to a class of variable stars, the singular character of which we shall consider further on. Instead of having a fixed light, as other stars, it is sometimes very brilliant and sometimes very faint ; it passes from the second to the fourth magnitude. It was at the end of the seventeenth century that this variability was first perceived. Observations made since that time have proved that it is periodical and regular, and that this period is of astonishing rapidity. Thus, to pass from its mini- mum to its maximum brilliancy, it only requires one hour and three quarters, so that in three hours and a half it has accomplished its entire cycle, has passed through all the intermediate decrees of light from the fourth to „ ■ J, „

. ° -i-i i p ,i ¥lS- 17. The Goat, Pleiades.

the second magnitude, *'nd ironi the

second to the fourth. The star £ of Perseus is double.

These are the principal stars which people the cir- cumpolar regions, on the one side ; presently we shall make better acquaintance with them. Whilst we are tracing lines of indication, let us have patience and finish our short ex- amination of this part of the sky. Take now the opposite side to the one we have just considered, still near the pole. Let us return to the Great Bear. Prolonging the curve of the tail we shall find at some distance from it a star of the first magnitude, this is Arcturus or a of the Cow-herd (Bootes). A small circle of stars that we see to the left of Bootes forms the Northern Crown.

70 Marvels of the Heavens.

The constellation of Bootes is traced in a pentagonal form. The stars which compose it are of the third magnitude, with the exception of a, which is of the first. This is the one nearest the Earth, for it is of the small number. of those whose distance has been measured. It is situated at 1,622,800 times the radius of the Earth's orbit from us. It is, moreover, a .coloured star ; seen with a telescope, it is red. The star s, which is seen above it, is double, that is to say, the telescope separates it into two distinct stars: one being yellow, the other blue.

By bringing a line from the Pole-Star to Arcturus, and erecting a perpendicular on the middle of this line, opposite to

Fig. 18. Northern Crown, Bootes, Arcturus.

the Great Bear, we find one of the most brilliant stars of the heavens, Vega, or a of the Lyre, near the Milky Way. It forms with the two just mentioned a large equilateral triangle. The line from Arcturus to Vega cuts the constellation of Hercules. Between the Great and Little Bear, a long series of little stars is seen passing round each other in rings and directing themselves towards Vega: these are the stars of the Dragon.

The stars bordering on the pole, and which have therefore received the name of Circumpolar Stars, are distributed into the groups we have just described. Now that we easily know how to find them in the sky, we may speak a little of their

The Northern Constellations. 71

ancient renown. In this group there is one of the greatest dramas of ancient mythology. To repeat this famous episode in a few words, I will mention that Cassiopea, wife of Cepheus, king of Ethiopia, one day had the vanity to be- lieve herself more beautiful than the Nereides, in spite of the African colour of her complexion. These sensitive nymphs, piqued to the quick by such pretensions, prayed Neptune to avenge them of such a gigantic affront ; the god allowed fearful ravages to be made by a sea-monster on the coasts of Syria. To stay the plague, Cepheus chained his daughter, Andromeda, to a rock and offered her in sacrifice to the terrible monster. But young Perseus, touched with so much misfortune, quickly bestrode the horse Pegasus, a model of coursers, took in his hand the Medusa's head, which froze the beholder with fright, and started for the fatal rock. He arrived naturally just at the moment when the monster was going to devour his prey, and nothing was more easily done than to petrify the monster by presenting Medusa's head to him, and to liberate the fainting Andromeda. This is a scenic effect from which painting has derived advantage in every sense ; there are perhaps as many Andromedas as Ledas, and these are innumerable. It must be owned also that the painter has not often so captivating a subject. The combat of Perseus with the monster is without equal in history.

' Le heros fond sur lui sans se laisser attendre, S'eleve, redescend, frappe encor, mais en vain. L'ecaille impenetrable a repousse l'airain. Le monstre est en fureur ; Andromede eperdue De cet affreux combat veut detourner la vue, Pousse un cri lamentable, et, levant ses beaux yeux, Eetrouve son vengeur qui plane dans les cieux, La fille de Cephee, en sa douleur mortelle, Pleure, fremit de crainte, et, ce n'est plus pour elle, Mais enfin le heros vers le monstre abhorre Precipite son vol, et d'un bras assure

72 Marvels of the Heavens,

Dans sa gueule beante enfonce cette epee Du sang de la Gorgone encore toute trempee. C'en est fait : a ses pieds revoyant son vengeur, Andromede a senti redoubler sa rongeur ; Les dieux sont satisfaits ; et pres de lui placee, Jusqu'au brillant Olympe elle a suivi Persee Par quels plus beaux exploits monte-t-on dans les cieux?

Daru.

In commemoration of these exploits, and not to give one an advantage over the other, all the family were placed in the heavens, and still remain there. With a little inclination, and knowing pretty well the conventional figures which divide our celestial atlas, we can see under the starry dome Cepheus enthroned, ciown on head and sceptre in hand; at his side his wife Cassiopea, seated on a chair ornamented with palms ; a little further on Andromeda, chained to a rock in the midst of an abyss ; an immense fish attacks her on one side ; Pegasus flying in the air a little in front ; and, lastly, the hero of the piece, Perseus, holding in the right hand a curved sword, and in the left the head with the hideous serpents. This is what the mythological eye may still contemplate at midnight during the beautiful season of summer

Bootes is seen above the Virgin on the zodiacal map. He was called Areas, and was the son of Jupiter and Oallisto. He was also called Atlas, who carries the world, because, for- merly, his head was close to the pole. As the Pleiades rise when Bootes sets, it has also been said that they were his daughters. In its vicinity shines like golden rain Berenice's Hair. It will be remembered that 246 years before Christ, Queen Berenice, who made a vow to cut off her hair if Ptolemy Euergetes, her husband, returned victorious, con- secrated it to the gods in the temple of Venus, after the victory of the prince. Her husband was very displeased with this unlucky idea, and it was feared that he would not be able to calm his passion, the more so, as the queen's hair was stolen the following night ; but the astronomer

The Koiihem Constellations. 73

Conon assured him that the regretted hair had been trans- ported to the sky by order of Venus, and actually shone as a constellation.

' Le mortel qui, des cieux ecartant tous les voiles, Calcula le lever, le coucher des etoiles, Conon me fit voler, par la faveur des dieux, Da front de Berenice a la voute des cieux. Humide encor des pleurs de ma reine fidele Je montai, nouveau signe, a la voute eteruelle ; Adinise entre la Vierge et le cruel Lion, Je guide a l'occident, en sa route incertaine, Le Bouvier qui vers l'aube a pas pesant se traine.'

Catullus.

The Hunting Dogs, or Greyhounds, are not distinguished by any remarkable star, but they possess the most beautiful nebula in the sky : that which I have before described and pictured (p. 35). It is situated in the left ear of Asterion, the northern Hunting Dog. As this left ear touches the tail of the Great Bear, it is easy to find it under the last star of the tail. To discern its form a good telescope is required. This is the nebula which resembles the Milky Way at a distance, and which was for some time considered as a globular cluster surrounded with a ring, until the day when Lord Rosse's great telescope showed it as the most mag- nificent spiral nebula in the heavens.

74 Marvels of the Heavens,

III.

THE ZODIAC.

* Le ciel devint un livre ou la Terre e'tcmne'e Lut en lettres de feu l'histoire de l'annee.'

Eosset.

It is known that the Sun in its apparent path above our heads, follows a regular and permanent course; that each year, at the same periods, it passes at the same height in the sky, and that it is not so high in the month of December as in the month of June ; the path it pursues is not less regular on that account, as it rises and falls in its circuit and at the same periods it always returns to the same points in the heavens. It is also known that the stars remain perpetually around the Earth, and, if they disappear in the morning, to shine again in the evening, it is only because the daylight effaces them. Now, the term zodiac is given to the starry zone through which the Sun passes during the entire course of the year. This word comes from gufaov, animal, an etymology taken from the character of the figures traced on this band of stars. Animals, indeed, predominate in these figures. The entire circumference of the heavens has been divided into twelve parts, which have been named the twelve signs of the zodiac, and our forefathers called them the ' houses of the Sun,' and again 'the monthly residences of Apollo,' because the Sun visits one each month, and. returns each spring to the commencement of the zodiacal cortege. Two Latin

The Zodiac. 75

verses give these twelve signs in the order in which the Sun crosses them, —

' Sunt : Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libraque, Scorpius, Arcitenens, Caper, Amphora, Pisces.'

Or rather in English : the Ram v , the Bull 8 , the Twins n , the Crab © , the Lion yp, the Virgin ni, the Scales *±, the Scorpion iT£, the Archer $ , the He-goat I? , Aquarius ;S7, and the Fishes X . The signs placed by these names are the primitive indications which bring them to mind : t1 represents the horns of a ram ; & the head of a bull ; £? is a stream of water.

If we have now become acquainted with our northern heavens, if its most important stars are sufficiently marked in our mind and their reciprocal relations with each other, we need no longer fear confusion, and it will be easy to recognise the zodiacal constellations. We must note especially that they all belong to one zone, to one belt of the sky, which may serve us as a line of division between the north and south. An easy method of finding this zone in a fine starry night, and to avoid useless search, is to take the Pole Star as the centre of a large circle, and to describe this circle by taking a radius equal to the half of the sky. The line thus described will extend beyond the zenith to the south, and will descend below the horizon to the north; it will mark therefore the celestial equator. Now the ecliptic, on the meridian line of the zodiac, is slightly inclined to the equator, but it only goes beyond it a little, so that our circle will give us, with sufficient exactitude, the line towards which we must look for our constellations.

These summary indications once given, the first signs will be easy to find. To have a complete and lasting knowledge of them, it is necessary to follow the description I am going to give on the accompanying maps, and afterwards in the evening to study the originals directly, of which the maps are

76 Marvels of the Heavens.

only copies. These same maps will again serve us, in the following chapter, in studying the southern constellations visible in England.

The Ram is situated between Andromeda and the Pleiades which we already know. By drawing a line from Andromeda to this group of stars the head of the Ram is traversed, formed by two stars of the third magnitude, arranged in a north-east direction. The Rani is the first sign of the zodiac, because, at the time when this principal part of the celestial sphere was established, the Sun entered this sign at the spring equinox. In the fable, it represents the Ram with the golden fleece of the Argonaut expedition, because at the moment when the Sun rises in this sign, guarded by a monster (the Whale) and by a Bull which vomits flames, the constella- tion Ophiuchus or Jason, comes out in the evening at the same point, and thus subjugates the vanished Ram. The Ram was also the symbol of Spring and the opening of the year. These two causes were indicated by the translator of Plutarch. The Bull comes afterwards. We go from west to east. We shall easily recognise it by the group of the Pleiades which sparkle on its shoulder, by that of the Hyades which glimmer on its forehead, and by the magnificent star which marks its right eye, the star Aldebaran, a, of the first magnitude. It is, moreover, situated just above the splendid constellation of Orion, which we shall meet again and make acquaintance with soon ; Aldebaran shines along the line of the Belt to the north-west. (To follow our map.)

The Pleiades, which are seen trembling at the north-west of Aldebaran, are a group of about 80 stars, resolved by the telescope.

The ancients counted in the Pleiades seven stars more brilliant than the ground sprinkled with golden dust. At the present time only six can be counted with the naked eye. which are called, — Alcyone or »j in the neck of the Bull, of the third magnitude ; Electra and Atlas, of the fourth ; Merope, Ma'ia and Taygeta, of the fifth. If we are to

The Zodiac. 77

believe Ovid, the seventh hid itself with grief at the taking of Troy. But the authorofthe ' Metamorphoses ' suspected nothing of the distance of stars and the length of passage of the rays in reaching us. If even one of the Pleiades hid itself at the taking of Troy, Ovid would still have seen it in the place which it formerly occupied, and perhaps even now we should have still seen it there. The Hyades form a V with Aldebaran, which occupies the southern extremity. Like the Pleiades,

Fig. 19. The Pleiades.

they announce rain; their name signifies to rain, and that of their companions signifies navigator. This inspired J.-B. Rousseau with the following verses: —

' Deja le depart des Pleiades A fait retirer les nochers, Et deja les tristes Hyades Forcent les frileuses Drvades De chercher l'abri des rochers.'

78 Marvels of the Heavens.

The Twins are easy to recognise to the east of the pre- ceding stars, their heads being formed of two beautiful stars, Castor and Pollux. We shall also reach them by a diagonal, crossing the Great Bear. Again, Castor, of the first magni- tude, forms a triangle with the Goat and Aldebaran. There- fore, nothing is more easily found. Descending towards the Bull, eight or ten stars terminate the constellation, and lower down, Procyon is met with, a star of the second magnitude. This region, marked with Orion, Sirius, the Twins, the Goat, Aldebaran and the Pleiades, is the most magnificent region of the celestial sphere. It is towards the end of Autumn that it shines in our hemisphere in the evening. The Twins are, in the fable, Castor and Pollux, sons of Jupiter, celebrated for their indissoluble friendship, for which they were rewarded by immortality. The changes of fortune have been compared by the poet to the destiny of these two brothers : —

' Jupiter lit l'homme semblable A ces deux Jumeaux que la Fable Placa jadis au rang des dieux ; Couple de deites bizarre, Tantot habitants du Tenare, Et tantot citoyens des cieux.'

The Greeks also gave the name of Castor and Pollux to those lights which appear round vessels after storms, electrical phenomena now called the fires of Saint Elmo.

The Crab or Cancer may be distinguished at the bottom of the line of Castor and Pollux, in five stars of the fourth or fifth magnitude. It is the least important body of the zodiac : —

' La timide ecrevisse a, la serre trainante Annonce le retour de la saison brulante : Son aspect, qui pour nous borne les plus longs jours, Fait du char du soleil retrograder le cours.'

While Hercules was fighting the Lion of Nemea, the Crab.

The Zodiac. 79

aiding the vengeance of Juno, pinched the heel of the hero, who crushed it with his foot, but the queen of heaven gave it its reward by placing it in the heavens.

The Lion is a large trapezium of four beautiful stars, situated to the east of the Twins. They may readily be found by continuing in the opposite direction the line, from a, /3 of the Great Bear, which served us to find the Pole Star. The most brilliant of these stars, a, is of the first magnitude and is called Regulus, the heart of the Lion ; the three others, /?, y, and d are of the second magnitude. The Sun enters the Lion at the summer solstice, and causes it to disappear by covering it with his fires; this is the victory of Hercules over the Lion of Nemea. It was also for the same cause the symbol of strength and power. Being the abode of the Sun during the month of July, it was again the sign of burning heats and of plagues which they sometimes brought with them. In the eyes of astrologers of the middle ages, this was its terrible aspect. The Virgin comes after the Lion, still to the east, as will be seen on the map. If we again use the very accommodating constellation which has until now been so useful to us, we must continue towards the south the great diagonal a, y from the square of the Great Bear, and we shall meet with a beautiful star of the first magnitude placed just to the left of our figure ; this is the Virgin's ear of corn, or Spica, a star known from all an- tiquity. Now that we can distinguish Arcturus, or Bootes (p. 70), and a of the Lion, we may also remark, that these two stars and Spica form together an equilateral triangle. The star /3, situated in the right arm of the Virgin, is called the Vintager. It forms a triangle with /3 of the Lion and Berenice's hair.

Emblem of justice and law, the Virgin represents Themis, with the scales at her feet. Why has she wings ? Perhaps because Justice, formerly on the earth, abandoned it for heaven. She is also Astrea, daughter of Jupiter and Themis, men's crimes having forced her to return to heaven

80 Marvels of the Heavens.

at the end of the golden age. She has the privilege of representing a great number of persons; the entire list would be too long, the following being only a few of them : Ceres, symbol of harvests ; Diana of Ephesus ; Isis of Egypt, goddess of Syria ; Atergatis or Fortune ; Cybele drawn by lions; Minerva, mo* her of Bacchus; Medusa; Erigona, daughter of the Cow-herd ; lastly, in the time of Virgil, she was the Sybil, who, with branch in hand, descended to the infernal regions. With so large a choice, she seems to have preferred the title of Daughter of Justice, exiled to the celestial regions by man's crimes.

The Scales is the seventh sign of the zodiac. To the east of Spica, two stars of the second magnitude are seen ; these are a and 13, marking the top of the Scales. With two other less brilliant stars, they form an oblique square on the ecliptic. Two thousand years ago, the Sun passed them at the autumnal equinox, and this is the origin of that sign which ' equals the day to night, work to sleep.'

J.-B. Rousseau expresses the same idea in one of his odes : —

' Le soleil, dont la violence Nous a fait languir si longtemps, Arme de feux moins eclatants Les rayons que son char nous lance, Et, plus paisible dans son cours, Laisse la celeste Balance Arbitre des nuits et des jours.'

The Scorpion, with its heart marked by the brilliant Antares, a star of the first magnitude, is easily recognised. It is not that the form can be distinguished ; for this form is not better sketched out by the stars which compose it, than the preceding figures, the Scales, the Virgin, &c. have been. But it is well understood that, when we speak of recognising a constellation, we refer simply to the groups of stars which

The Zodiac. 81

bear its name and not to its mythological figure. An tares, a of the Scorpion, is on the continuation of the line which would join Regulus (a of the Lion) to Spica ; these are three stars of the first magnitude placed in a straight line, in a west-east direction. Antares also forms with Lyra and Arcturus a large isosceles triangle, the latter star being at the vertex. The second star of the Scorpion, /3, of the second magnitude, marks the head. A string of stars of the third magnitude traces out the curved tail.

The Scales and Scorpion only formed one sign with the Latins before Augustus : the Scales were then the claws of the Scorpion. As Augustus was born on the 23rd of Sep- tember, flattery leagued itself with astrology to celebrate the happiness promised to the Earth by the birth of this emperor ; the Scales, which the Egyptians had formerly instituted in the original sphere, were replaced in the heavens as a symbol of Justice.

The verses of the Eneid may now be easily interpreted. As a sign of misfortune and fear, the Scorpion was cursed among all the constellations. It was said, especially, that it had an invincible hatred towards Orion, because this figure sets when the former rises, and vice versa. It was not only the terror of the stars, but also the terror of the Sun himself, that Ovid has described it to us.

Sagittarius (the Archer), forming an oblique trapezium, is a little to the east of Antares, still following the direction of the ecliptic. It only contains stars of the third and less magnitudes ; a, d, y, form the arrow ; the last, y, is called Nushaba by the Arabs. The star it marks the head. This constellation never rises much above the horizon of London In the fable, it is the Centaur Chiron, the tutor of Achilles, Jason, and Esculapius, and the inventor of the art of riding. This was the last lord of this ancient race. Doubtless, the vicinity of the Scorpion influenced the opinion of the poets with regard to itself, for it is not represented under very favourable colours.

82 Marvels of the Heavens,

' Deja du haut des cieux le cruel Sagittaire Avait tendu son arc et ravage la terre ; Les coteaux, et les champs, et les pres defleuris, N'offraient de toutes parts que de vastes debris ; Novembre avait compte sa premiere journee.'

Capricornus (the He-goat) is not rich in bright stars. Those which sparkle on his forehead, a and /3, are the only ones which can be distinguished by the naked eye. They are on the continuation of the line which passes from Lyra to the Eagle. The region of the Zodiac which we are now visiting is the poorest in the heavens ; it presents a striking contrast with the opposite region, where we admired Alde- baran, Castor and Pollux, the Goat, &c.

Above Capricornus shines Altair, or a of the Eagle : the stars of Antinous form a trapezium on the path from Capricornus to the Eagle. In some authors, this sign represents the goat Amalthea, which nursed Jupiter on Mount Ida, and received a place in heaven as a reward. According to others, it represents the return of the Sun to the winter solstice through the gates of the tropics. Again, according to others, it was a he-goat which was brought up with the king of the gods, and which discovered and sounded the marine trumpet, and produced fear among the Titans in their war with Olympus. The frightened gods hid themselves in the forms of different animals ; Apollo changed into a crane, Mercury into an ibis, Diana into a cat. Such a meta- morphosis was never seen. Lastly, Pan into Capricornus, having a goat's body and the tail of a fish. He appeared, also, to wish to steal away with the giants who scaled heaven.

Aquarius forms with his three tertiary stars a very obtuse triangle. The base is prolonged in a string of stars from the side of Capricornus and towards the left to the Urn. Thence begins a sinuous line of very small stars descending to the horizon. This is the water poured out by Aquarius.

The Zodiac. 83

Aquarius appears to personify Ganymede, who was raised by Jupiter's eagle to serve as cupbearer to the gods after the fall of Hebe.

1 Jupiter, qui d'Hebe prononce la disgrace, Au jeune Ganymede a destine sa place ; Le nouvel echanson, hote digne des cieux, De torrents de nectar enivre tous les dieux.'

The Fishes, the last sign of the Zodiac, lie to the south of Andromeda and Pegasus. The northern fish is that which wished to devour Andromeda ; the western fish advances in the square of Pegasus ; they are bound together by a band. Not so apparent as the preceding, this constellation is com- posed of two rows of very small stars, which start from a of the third magnitude, the knot of the band, and diverge, one towards a of Andromeda, the other towards a of Aquarius. Ovid tells how Venus and Love, wishing to steal away at the pursuit of the giants, crossed the Euphrates on two fishes, which were for this placed in heaven. It is related that two fishes having found an egg of a very beautiful shape, drew it to shore, that a dove sat on it, and Venus came forth. It was from this time that the Syrians abstained from feeding themselves on fish. This sign is the last abode of the Sun before the renewing of the year, in the month of February ; this was the time of the inundation of Egypt and that of fishing with us. It closes the circle of the zodiacal constellations.

* Enfin aux derniers rangs paraissent les Poissons, Qui, fermant a la fois et rouvrant les saisons, De l'hiver rigoreux temperent 1'influence, Et d'un nouveau printernps raniment l'esperance.'

Eicard.

If our descriptions have been well followed on our map, the zodiacal constellations will be as well known as those of the north. Little now remains before we become familiar with the

84 Marvels of the Heavens,

whole heavens, yet there is an indispensable complement to the preceding. The circumpolar stars are always visible above the London horizon ; at any time of the year that we wish to observe them, they may always be found, either above, below, or on one side or the other of the Pole Star, which has served us to find them, and always preserving the same relation one with the other. The zodiacal stars do not resemble them in this point of view ; for they are sometimes above the horizon and sometimes below it. We must, therefore, know at what time they are visible. For this it will be sufficient to remember the constellation which is at the centre of the heavens at nine o'clock in the evening, on the first day of every month, that, for instance, which at that hour crosses a line drawn from the Pole Star, from north to south, dividing the sky into two parts. This line is called the meridian, and all onr figures cross it, passing from east to west. Marking each of the constellations which pass at the indicated hour, we thus give the centre of the visible constellations. Looking for the northern ones at the north ; to its left those which precede the indicated constellation in the order of the signs ; to its right those which follow it, all will be found without difficulty. On the first of January the Bull passes the meridian. Notice Aldebaran and the Pleiades. — 1st of February : the Twins have not yet reached there, they are seen a little to the right. — 1st of March : Castor and Pollux have passed, Procyon at the south ; the little stars of the Crab to the right. — 1st of April : the Lion, Regulus. — 1st of May : 13 of the Lion, Berenice's Hair. — 1st of June: Spica of the Virgin, Arcturus. — 1st of July: the Scales, the Scorpion. — 1st of August: Antares, Ophiuchus. — 1st of September: Sagittarius, the Eagle. — 1st of October: Capricornus, Aquarius. — 1st of November: the Fishes, Algenib or -^ of Pegasus. — 1st of December : the Ram.

Our general revision of the starry heavens ought now to be completed by the stars of the Southern sky.

I have only given a rapid summary of the mythological

The Zodiac. 85

explanation of the signs of the Zodiac ; the uncertainty which reigns over their origin has allowed many to be suggested. I shall only recount here, that which supposed them to be the twelve labours of Hercules, a suggestion which does not lack a certain ingenuity. Hercules would be no other than the Sun himself considered in his attributes relatively to the different times of the year. Francoeur, in his Uranographie, according to Lalande and the philosopher Dupuis, charged himself with supporting this curious s\stem.

The entrance of the Sun into the solstitial Lion which he made to disappear by covering it with his fires, is the victory over the Lion of Nemea. In proportion as the Sun advances he crosses Cancer, the Lion, and the Virgin; the different parts of the Hydra are eclipsed by turn ; first the head, then the body, and lastly the tail ; but then the head reappears in its heliacal rising. This is the triumph over the Hydra rising again from the Lake Lerna, which Hercules burned, after having crushed the Crab which aided it. The Sun cross- ing the Scales at the time of the vintages covers the Centaur with his fires. The fable states that the Centaur Chiron, having received Hercules, taught him the art of making wine. It adds that, in a drunken dispute, the people of the Centaurs wished to kill Hercules' host, which forced the hero to fight with them ; this appears to relate to the setting of Sagittarius in the evening. Lastly, in hunting, he conquered a monster, called the wild boar of Erymanthus, which was believed to refer to the rising of the Great Bear in the evening.

Cassiopea, who is represented also by a hind, in the morning sets in the waves when the Sun is in Scorpion, which happens at the autumnal equinox ; it is this hind with golden horns which, in spite of its wonderful velocity, Hercules tired out in a race, and caught at the water's edge when she reposed.

At the rising of the Sun in Sagittarius, the Eagle, Lyra (or the Vulture), and the Swan situated in the Milky Way.

86 Marvels of the Heavens.

disappear at once ; these are the birds of the Lake Stym- phalis, driven out of Arcadia by Hercules, whose arrow is placed among them. Capricornus, or the celestial He-goat, is bathed in front by the water of Aquarius ; these are the stables of Augias cleansed by a river passing through them.

The Sun in Aquarius, or the winter solstice, was near Pegasus ; in the evening the Vulture was seen to set, whilst the Bull passed the meridian ; it was said that Hercules, on his arrival in Elis, to fight the Bull of Crete and the Vulture of Prometheus, mounted the horse Arion and in- stituted the Olympic Games, which are celebrated at full moon of the summer solstice; the moon is then exactly in Aquarius, that is to say, in the region opposite to the Lion. The carry- ing off of the mares of Diomedes, son of Aristes, relates to the heliacal rising of Pegasus and the Little Horse, the Sun being in the Fishes. These two Horses are placed above Aquarius, which is Aristes.

Hercules afterwards starts for the conquest of the Golden Fleece, Aquarius and Serpentarius rise in the evening, whilst at the same time the Ram, Cassiopea, Andromeda, the Pleiades, and Pegasus set. Hence the victory of Hercules over Hippolyte, queen of the Amazons, whose belt (Mirach) shines with a bright light. Many of these warriors had the names of the Pleiades.

At the rising of the Bull, the cow-herd (Bootes) sets, and the Great Bear (the oxen of Icarus) rises. This is the defeat of Geryon and the carrying off of his oxen. Hercules kills Busiris, persecutor of the Atlantides : the fable which alludes to Orion pursuing the Hyades, and who is then hidden in the solar beams. The return of Spring is moreover explained by the destruction of the venomous reptiles of Crete and by the defeat of the brigand Cacus ; that of the river Achelaus, changed into a bull, relates to Eridanus, which is situated below.

After having founded Thebes in Egypt, Hercules went to

The Zodiac. 87

the infernal regions, delivered Theseus and carried off Cer- berus. The Sun has arrived in the northern hemisphere ; the Great Dog, whose heliacal setting took place in the pre- ceding sign, is now absorbed in the Sun's brightness ; he is taken from the infernal regions, and brought to the light. The river of Aquarius, which rises in the -evening with the Swan, when the Sun has traversed the constellation of the Twins, is Cycnus conquered at the borders of Penea.

The Northern Dragon and Cepheus, or the garden of Hesperides, rise at the setting of the Sun, under Cancer; hence the voyage of Hercules in Hesperia. The time of the heliacal rising of the constellation of Hercules is in autumn : the apples of the Hesperides are an allusion to this season.

Returned to the summer solstice, the Sun recommences its revolution : this is the apotheosis of Hercules. Fable re- lates that Dejanira, seeking for a love-potion to keep her husband, sent him a shirt soaked in the blood of the Centaur Nessus. Hercules put it on to sacrifice to the gods, and to ask of them the immortality promised for his exploits: but, devoured by the poison in the garment, the hero burnt himself on the funeral pile. This is the sense of this fable. The Sun has entered the Lion and rises, whilst the constellations Hercules and Aquarius are about to set. The Centaur sets a little after the Lion ; this one then causes Hercules to die, and Aquarius, Ganymede, is carried off to pour out nectar to the gods, in the place of Hebe, given to the hero. The reconciliation of Hercules and Juno relates to Aquarius, who is dedicated to the goddess.

Hercules lived 52 years, had 52 wives and accorded the Nemean honours to 360 of his companions who died for him : this alludes to the 52 weeks of the year and to the 360 degrees of the Zodiac. The Pillars of Hercules were the western limits of the known Earth, where the Sun seemed each day to set in the sea.

However vague many of the interpretations just put forth may seem to be, adds Francceur, there are some so

88 Marvels of the Heavens.

remarkable that they cannot be supposed to be altogether the effect of chance : thus Hercules was not a hero whose good actions excited men to erect altars to him; but the Sun, considered in his attributes relative to the different epochs of the year; an opinion agreeing with the most revered testimonies of the ancients.

4tf

IV.

THE SOUTHERN CONSTELLATIONS.

' Qui done sur l'Oce*an, dans 1'ombre et le silence, Eleve avec orgueil son front majestueux ; Et, bravant de Phoebe le disque lumineux, Devant son trone meme insulte a sa puissance ?

* C'est toi, noble Orion: tes feux etincelants Des soleils de la nuit effacent la lumiere, Comme le dieu du jour, entrant dans la carriere, Efface de Phoebe les rayons palissants.

' Sur le trone des airs fais briller la couronne ; "Viens, heros indompte, regner sur nos climats, Leve-toi ! que nos yeux attaches a tes pas Contemplent a loisir l'eclat qui t'environne.

' Percant des sombres mers les nocturnes brouillards Sous l'orgueilleux fardeau de ta pesante armure, Je te vois deployer ta superbe ceinture Et de l'homme etonne commander les regards.

•Le Taureau loin de toi recule epouvante : II rouie avec effroi sa prunelle sanglante; Tandis que vers le nord s'enfuit l'Ourse trprablante Aux eclairs mena9ants de ton glaive irrite.'*

1 A tout seigreur tout honneur.' Orion is the most beautiful constellation ; we must not pass it without doing homage tc it, and tha best way of rendering homage to persons of worth, is to learn how to understand them.

Let us observe our map : below the Bull and the Twins, to the south of the Zodiac, you will notice this giant

* Newland, quoted by Quetelet in his Astronomy.

90 Marvels of the Heavens.

who raises his club towards the forehead of the Bull. Seven bright stars are distinguished ; two of them, a and ft are of the first magnitude ; the other five are of the second ; a and 7 mark the shoulders, % the right knee, /3 the left foot; 8, s, £ mark the belt; below this line is a luminous train of three stars close together, this is the Sword. Between the western shoulder, 7, and the Bull, is seen the Shield com- posed of a curved string of little stars. The head is marked by a little star, X of the fourth magnitude ; & and v denote the raised arm.

Fig. 20. — Orion, Aldebaran, Sirius.

For more clearness, we give the arrangement of the prin- cipal stars of this magnificent asterism.

Orion is on the continuation of the line which joins the Pole Star to Capella. The four stars, a, 7, ft %, occupy the angles of a great quadrilateral; the three others d, s, £ are close together in an oblique line in the middle of this quadri- lateral ; a, in the north-east angle is called Betelgeuse (not Beteigeuse, as generally printed), ft of the south-west angle, is called Rigel.

The line of the Belt, prolonged on both sides, passes on the north-west by the star Aldebaran in the eye of the

The Southern Constellations. 9i

Bull, which we already know, and on the south-east by Sirius, the most beautiful star in the heavens, with which we small soon occupy ourselves. It is during fine winter nights that this constellation shines over our heads. No other season is so magnificently constellated as the winter months. Whilst nature deprives us of certain enjoyments on the one hand, it presents us with others no less precious. The wonders of the heavens present themselves to amateurs from the Bull and Orion at the east, as far as the Virgin and Bootes at the west ; of eighteen stars of the first magnitude, which may be counted in the whole extent of the firmament, a dozen are visible at nine o'clock in the evening, not count- ing many beautiful stars of the second order and the remark- able nebulae and heavenly objects very worthy of the atten- tion of mortals. These twelve stars are : Sirius, Procyon, Capella, Aldebaran, Spica, the heart of the Hydra, Eigel, Betelgeuse, Castor and Pollux, Regulus, and /3 of the Lion.

Thus it is that nature establishes everywhere harmonious compensation, and whilst it darkens our short and frosty winter days, it gives us long nights enriched with the wealthiest creations of the heavens.

The constellation of Orion is not only the richest in bright stars, but it conceals also treasures for the initiated which no other can present. We might almost call it the California of the heavens. We will enumerate its riches, and shall then find greater delight in contemplating it in the heavens.

Let us speak first of its nebula, situated below the second star of the Belt. The first time that Huygens, its discoverer, admired this cosmical beauty, in 1656, he was sufficiently astonished to say, that it seemed an opening in the sky which threw light on a more brilliant region. ' Astronomers,' he states, ' have counted in the sword of Orion three stars very near each other. In 1656, I accidentally observed that, in place of one of these stars which occupy the centre of the group, there was a dozen of them, a result which is not rare

92 Marvels of the Heavens,

to obtain with telescopes. Of these stars there were three which, like the first, nearly touched each other, and four others seemed to shine through a cloud in such a manner that the space which surrounded them appeared much more luminous than the rest.'

Since that period this nebula has been studied with a kind of predilection ; it has been minutely examined and the different regions of its cluster have been studied and de- scribed in all their details. In proportion as the instruments have become more powerful, the stars, which constellate it, appear more numerous, which has happened in all telescopic observations of nebulae ; and. whilst in early days it was asked with great uncertainty if there was only a phosphorescent cloud, a vaporous mass — astronomers afterwards arrived at the conviction that it was formed of an immense number of heaped-up suns, and then again that it was a true cosmical cloud. At the centre is seen a brighter part of singular form ; Sir J. Herschel compared it to the head of a monstrous animal, with gaping mouth, the nose being prolonged like the trunk of an elephant.

It occupies a large space in the sky, its apparent dimen- sion being equal to that of the lunar disc. When we think of the distance which separates us from this agglomeration, we are dismayed at the real extent which it embraces in the midst of the boundless void.

But the strangest phenomena which are attached to this nebula are the changes which are observed in it. The drawings which are now taken differ from those which were taken half a century ago. Again this year (1867), there has been noticed in England an indication of brightness, through a dark portion, which did not exist ten years ago. Astro- nomers agree that there is no possible delusion in some of these observations, and that this distant agglomeration is the seat of formidable disturbances.

* The general impression that I have received from these observations,' said the director of the Russian Observatory

The Soldi tern Constellations. 93

not long ago, ' is that the central part of the nebula is in a state of continual agitation, like the surface of the sea.'

Orion possesses many other riches. The star of the left foot, Rigel, is one of the most beautiful double stars. (We shall soon commence this chapter of Sidereal Astronomy.) This double star is composed of a white and a blue sun. In calm and clear nights which we sometimes have in the winter, it appeared to me sometimes that the reflection of the blue star tinted the brightness of the white sufficiently to cause this to seem slightly tinted with blue, especially when it is compared with the golden points which sprinkle the surrounding sky.

Two other binary systems are met with in the two stars at the extremities of the Belt. The first to the right is composed of a white and a purple sun ; the second, of a yellow and a blue sun. Thus here are three systems of the most dissimilar worlds united in the same constellation. In each of these systems two suns instead of one ; not only two suns like ours, but two differently coloured suns ; in the planets which belong to the first, a white and a blue body dispute the empire of the day with each other, giving rise, by the numberless combinations of their heat, light, and electrical power, to a variety of actions incomparable and unimaginable by us, who are devoted to one sun. In the planets which belong to the second, it is a purple sun which diversifies the white light of its compeer. In that of the third the number of colours is essentially different from ours, as there is no white light the generator of every tint ; and presents an unknown series of shades, the result of the com- binations of gold and sapphire. These planets are doubtless green, and the colour of the objects on their surface must probably oscillate round this medium either as yellow or blue.

But this wealth of stellar systems does not yet constitute all the patrimony of this beautiful constellation of Orion. It contains, besides, the most complex of multiple systems

94 Marvels of the Heavens.

which have ever been met with in the heavens. In the nebula of which I have just spoken, an extraordinary star is met with, the star marked 8 in the catalogues, a little below the Sword. This star, divided by the telescope, presents to our admiration six suns collected in one point of the heavens. Fourprincipal stars of the fourth, sixth, and seventh magnitudes, are arranged at the four angles of a trapezium ; the two stars at the base have each a very feeble companion. That these six stars form in reality a physical system and that they are connected together, like the binary systems, by the law of attraction, is a statement I do not wish to affirm. It may be that this is only an optical effect — that these six stars are in reality completely independent of each other, situated at immense distances and depths, but, being on the line of sight very near together, they appear to us collected on one plane. Never- theless, there are probabilities in favour of the opinion which considers this sextuple star as an actual system, especially when we see that the movement belonging to the principal star is shared by the five others.

Another star in Orion, the twenty-third, is equally remarkable, being double, and instead of having its principal white and its small one blue, as in the generality of cases, it is the contrary that is noticed.

This is a great deal for one constellation ; but for this beautiful and ancient figure, about which Job sang three thousand years ago, I have a sympathy for which I cannot and will not defend myself. Between the Pleiades and the beautiful Sirius, it presents to me a magnificent celestial region, enriched with varied worlds, which makes one dream of distant life. Between ourselves, I read an astrological treatise of the middle ages : its title was ' Flamma Orionis.' Since that time this name is dear to me : I love it ! Now, you know what happiness it is to lovers to speak continually of the object of their devotions. Following its course, like the Sun, and the planets, and zodiacal constellations, the Moon sometimes passes near Orion. It then hides the

The Southern Constellations, 95

stars over which its path conducts it. In speaking of Orion, the American poet, Longfellow, has pictured this occultation in bright colours : —

1 Sirius was rising in the east, And, slow ascending one by one, The kindling constellations shone. Begirt with many a blazing star, Stood the great giant Algebar, Orion, hunter of the beast ! .His sword hung gleaming by his side, And, on his arm, the lion's hide Scattered across the midnight air The golden radiance of its hair. The moon was pallid, but not faint, And beautiful as some fair saint Serenely moving on her way In hours of trial and dismay, As if she heard the voice of God. Unharmed, with naked feet she trod Upon the hot and burning stars, As on the glowing coals and bars That were to prove her strength, and try Her holiness and her purity.

4 Thus moving on with silent pace, And triumph in her sweet, pale face, She reached the station of Orion. Aghast he stood, in strange alarm ! And, suddenly, from his outstretched arm, Down fell the red skin of the Lion Into the river at his feet. His mighty club no longer beat The forehead of the Bull ; but he Reeled as of yore beside the sea, When, blinded by (Enopion, He sought the blacksmith at his forge, And, climbing up the mountain -gorge, Fixed his blank eyes upon the Sun.'

96 Marvels of the Heavens.

In the fable, Orion, the handsomest man of his time, was of such high stature, that when he walked on the bottom of the sea, his head exceeded the height of the waves ; which means that this constellation is half beneath the equator and half above.

I have forgotten to add, that the three oblique stars which form his belt have been named the Three Magi Kings, Jacob's staff, and that in France we simply distin- guish them under the name of the Rake.

'To the south-east of Orion, on the line of the Three Kings, shines the most magnificent of all stars, Sirius, or a of the constellation of the Great Dog. This star of the first magnitude marks the upper eastern angle of a great quadri- lateral, whose base reaches the London horizon, and is adjacent to a triangle. The stars of the quadrilateral and the triangle are all of the second magnitude. This constellation rises in the evening, at the end of November, passes the meridian at the end of January, and sets at the end of March.

Sirius being the most brilliant star of the heavens, and astronomers daring to attempt operations relative to the study of the distances of stars, this attracted their attention. After long and minute study they succeeded in determining its distance; 1,375,000 times the distance of the Sun. To traverse the distance from the Earth to this star, light takes nearly twenty-two years. Hence, it follows that, when we see it, it is not the Sirius of to-day which is before our eyes but rather the Sirius of twenty-two years ago ; the ray of light which reaches our eye now left Sirius during the year 1848.

The name we now give to a of the Great Dog formerly belonged to the whole constellation, and not a single Egyptian monument is found where this figure is indicated without its representing Sirius, a name derived from Osiris, the Sun. At the time the constellation was formed, the summer solstice happened when the Sun crossed Oapricornus ; the rising of Sirius announced to Egypt the time of the overflowing of the Nile, and like a faithful dog warned men to be on their

The Southern Constellations. 97

guard. The role of Sirius did not stop here. The civil year of the Egyptians being exactly 305 days, and their kings swearing never to allow the intercalation of supplementary days, this year advanced a day every four years on the solar year, and again coincided with it at the end of 365 times four years — in 1460 years ; but during this time the civil periods, agricultural labours, fetes, and the different parts of the calendar, could not be fixed by unchangeable dates. They therefore chose a si.^n in the heavens which announced the period of the solstice ; the rising of Sirius in the morning, which was then called Sothis, announced the desired epoch. The heliacal (solar) rising of this star only happened on the same day after 1461 years.

Since those ancient days, a movement of the Earth which slowly modifies the path of the Sun among the constellations, which is called ' the precession of the equinoxes,' has deprived Sirius of its faculty of predicting the inundation and the solstice; its heliacal rising happens in Egypt now on the 10th of August instead of the 20th of June. But at the beginning of our era, it took place in July, in the midst of the great heats and the diseases they engender. Hence, this con- stellation was accused of a malignant influence, as may be seen in Sophocles and a hundred other more modern authors ; it gives fever to men and madness to dogs. The term dog- days is derived from this. In order to conciliate Sirius, they raised altars on which were sacrificed the quail and the goat. They dreaded the star of the south.

' Jam rapidus torrens sitientes Sirius Indos Ardebat.' — Georgics, iv. 425.

4 Sirius ardor ; Ille sitim morbosque ferens mortalibus segris Nascitur, et lsevo contristat lumine coelum.' — ^Eneid, x. 273.

Sirius, or the Dog-star, was also called the Dog of Procris, wife of Oephalus, who pierced her with an arrow shot acci- dentally, as Ovid relates at great length. Jean- Baptists

98 Marvels of the Heavens,

Rousseau, who sometimes liked to parade his astronomical knowledge, has not quite succeeded, in speaking in our time of the burning Sirius in an ode to the Abbe Chaulieu ; it is charming nevertheless :

'Mais aujourd'hui qu'en nos plaines Le Chien brulant de Procris De Flore aux douces haleines Desseche les dons cheris,

' Veux-tu d'un astre perfide Kisquer les apres chaleurs, Et, dans ton jardin aride, Secher ainsi que tes fleurs ? '

Sirius has a long and good reputation as a dog. After all the services which he had rendered to the Egyptians, Jupiter charged him with the care of his dear Europa ; after the carrying off, he passed through the hands of Minos, Procris, Cephalus, and Aurora. Well-known authors even think that, in spite of all that precedes, he was Cerberus, the dog with three heads ; their opinion is supported by this coincidence, that the Great Dog guards at the equator the lower hemisphere of the Egyptians, in the same manner as Cerberus watched the region of Tartarus. It is seen that this dog claims a very ancient nobility. No heraldic title can boast of such antiquity.

The Little Dog, or Procyon, which we have already seen on our zodiacal maps, is above Sirius and below the twins, Castor and Pollux, to the east of Orion. No bright star distinguishes it, unless it be a. From a mythological point of view, it shares with the Great Dog most of the fables attributed to the latter.

The Hydra is a long constellation which occupies that quarter of the horizon, under the Crab, Lion, and Virgin. The head, formed by four stars - of the fourth magnitude, is to the left of Procyon, on a line drawn by this star and Betelgeuse. The western side of the great trapezium of the

The Southern Constellations. 99

Lion, like the line joining Castor and Pollux, is directed to a, of the second magnitude : it is the heart of the Hydra. On the back of the Hydra, stars of the second order may be noticed, the Raven and the Cup. Being like a river in its meanderings, the Hydra has been regarded as an inhabitant of the Nile and its representative. As the ship Argo is not far from here, some have even gone so far as to explain by certain aspects the deluge of Deucalion, who escapes in a vessel, and who, forty days after, makes certain that the waters have retired by sending forth a raven.

Eridanus, the Whale, the Southern Fish, and the Centaur are the only important constellations we still have to describe. They will be found in the order indicated, to the right of Orion. Eridanus is a river composed of a series of stars of the third and fourth magnitude, which descends and winds from Orion's left foot to Rigel, being lost under the horizon. After having followed long windings, invisible to us, it is terminated by a beautiful star of the first magnitude, a or Achernar. This was the river into which Phaeton, who awkwardly conducted the car of the Sun, fell : it was placed in heaven to console Apollo for the loss of his son.

' Nevertheless Phaeton, his hair on fire, falls from the height oi heaven, and leaves behind him a long train ot flame. - Eridanus, who flows in distant parts of the country, and had seen the birth of this unfortunate prince, received him in his waves, and washed his face, which was covered with foam.'

Below the Ram, a star of the second magnitude is met with, which forms an equilateral triangle with the Ram and the Pleiades : this is a, or the jawbone of the Whale ; a, /a, g and y form a parallelogram — this is the head. The base, a, y, is prolonged to a star of the third magnitude, d, and to a star of the Neck marked o. This star is one of the most curious in the heavens ; it is called the Marvellous, Mira Ceti. It belongs to the class of variable stars. Sometimes *t equals in brightness stars of the first order, at others it

100 Marvels of the Heavens.

becomes completely invisible. Its variations have been watcbed since the end of the sixteenth century, and it has been noticed that the period of increase and decrease is in the mean 331 days, but always irregular, being sometimes 25 days behind or 25 days in advance. The study of these variable stars will present curious phenomena to us.

The Whale was sent by Neptune to devour Andromeda, I shall not return to the history of this poor princess.

Four stars of the third magnitude form the tail of this cotacean and descend towards Fomalhaut, or a of the Southern Fish, which receives water from Aquarius. This asterism rises very little above the horizon of London.

Lastly, the constellation of the Centaur is situated below Spica of the Virgin. The star Q, of the second magnitude, and the star /, of the third, mark the head and shoulder : this is the only part of the figure which rises above the horizon of London. The Centaur contains the star nearest to the Earth, a, of the first magnitude. It is also in this constellation that the beautiful regular nebula is found, which we have already admired, the globular cluster Omega of the Centaur. The feet of the latter touch the Southern Cross, formed of four stars of the second magnitude, always hidden below our horizon. A little further south is the south pole.

- vi

THE NUMBER OF THE STARS— THEIR DISTANCES.

1 II est pour la pense*e une heure . . . une heure sainte Alors que s'enfuyait de la celeste enceinte, De l'absence cln jour pour consoler les cieux, Le crepuscule aux moots prolonge ses adieux. On voit a I'horizun sa Jueur incertaine, Comme les bords tlottants d'une robe qui traine, Balayer lentement le firmament obscur, Ou les astres ternis revivent dans l'azur. Alors ces globes d'or, ces iles de lumiere, Que cberche par instinct la reveuse paupiere, Jaillissent par milliers de l'ombre qui s'enfuit, Comme une poudre d'ur sous les pas de la nuit.'

Lam amine.

In order that the mind may be less confused in the midst of these thousands of sparkling points, it has been agreed from the highest antiquity to class the stars according to their apparent brightness, besides the divisions we have just mentioned. We have seen that the brightest stars have been called stars of the first order, or magnitude, although this term does not imply anything relative to the actual size or brightness of the stars ; those which follow, still in the order of their apparent brightness, have been called stars of the second magnitude ; then come those of the third, fourth, and fifth magnitude, according as they appear smaller ; lastly, stars of the sixth magnitude are the last stars visible to the naked eye.

The stars of the first magnitude are eighteen in number. In reality, the eighteenth, that is to say, the least brilliant of

102 Marvels of r.ke Heavens.

the series, might as well be inscribed in the first rank of the stars of the second magnitude, and the first of this second series might, in the same way, be added to the stars of the first magnitude. There is nothing in the nature of these separations which necessitates our classification; but as we must stop at one star, and a series is to be made, it has been agreed to make the list oi itars of the first magnitude as follows : —

List of Stars of the First Magnitude in the order of their decreasing brightness.

1. Sirius, or a. of the Great Dog.

2. n of Argo (variable star).

3. Canopus, or u of the Vessel.

4. a of the Centaur.

5. Arcturus, or a. of the Cowherd (Bootes).

6. Rigel, or /3 of Orion.

7. Capella, or u, of Auriga.

8. Vega, or a. of Lyra.

9. Procyon, or a of the Little Dog.

10. Betelgeuse, or a, of Orion.

11. Achernar, or a, of Eridan.

12. Aldebaran, or a. of the Bull.

13. /3 of the Centaur.

14. cc of the Cross.

15. Antares, or ec of the Scorpion.

16. Atai'r, or oc of the Eagle.

17. Spica, or a. of the Virgin.

18. Fomalhaut, or u. of the Southern Fish.

It is generally thought that the brightest are the nearest, and that the stars appear to us smaller the more distant they are from us. Hence it follows that the number of the stars must increase in the inverse ratio of each magnitude : that the stars which form the second series, for instance, being on a more distant, and consequently larger, visual circle than that of the first series, are more numerous : that the third series

The Nu ruber of th e Stars. 1 03

is richer than the second, and so on. This is precisely what is observed. The stars of the second magnitude numbei about 55; of the third, 170; of the fourth, 500, &c. The following is, indeed, an easy method of knowing approxi- mately the number of stars of each order. It has been re- marked that each class is generally three times more numerous than that which precedes it; so that by multiplying the number of stars which compose any series by three, we have nearly the number of those which compose the following series. By this calculation the number of the stars of the six first magnitudes- — in other words, that of the whole of the stars visible to the naked eye — would give a total of about 6000. Generally it is thought that more may be seen; we think we can count them by myriads, by millions : in this as in everything else, we are always given to exaggeration! Yet, in fact, the number of stars visible to the naked eye, in both hemispheres does not exceed this figure, and even then there are few eyes good enough to see more than 4000 or 5000.

But here, when our feeble sight gives way, the telescope, that giant eye which increases from century to century, piercing the depths of the heavens, constantly discovers new stars. After the sixth magnitude the first glasses revealed the seventh. Then they reached the eighth, the ninth. It is thus that thousands have increased to tens of thousands, and that tens of thousands have become hundreds of thou- sands. More perfect instruments have cleared these distances, and have found stars of the tenth and eleventh magnitudes. From this period they began to count by millions. The num- ber of the stars of the twelfth magnitude is 9,556,000 ; added to the eleven preceding magnitudes the total exceeds four- teen millions. By the aid of still greater magnifying power, these limits are again surpassed. At the present time, the total number of stars from the first to the thirteenth magnitude inclusive, is calculated at 43,000,000. *The sky is truly transformed. In the field of the telescope,

104

Marvels of the Heavens.

neither constellations nor divisions are distinguished ; bnt a fine dust shines in the place where the eye, left to its own power, only sees darkness on which stand out two or three

Fig. 21. A part of the constellation of tbe Swan, as sesn through the telescope.

stars. In proportion as the wonderful discoveries in optics will increase the visual power, all regions of the sky will be covered with this fine golden sand ; and a day will come

The Number of the Stars. 105

when the astonished eye, raised towards these unknown depths, will be startled by the accumulation of stars which succeed each other in an endless manner, and will only discover a delicate tissue of light.

What is the extent occupied by these myriads of stars which succeed each other eternally in space ? This question has always attracted the attention of astronomers as well as that of simple thinkers ; but they were not able to com- mence any researches relative to its solution until lately, when delicate means have become accessible to us

The ancients did not form the slightest idea of the distance or nature of the heavenly bodies : they were thought to be emanations from the Earth, rising like the ignes fatal over marshy places. This would be a long and curious story, and, like that of all primitive ideas, but little in harmony with the .grandeur of creation. To possess the Fig. 22. The same

" _ . it c i seen with, the na-

power 01 measuring the distance ot the kedeye. nearest star, it is necessary to measure the thickness of a hair. A long time elapsed before this was accomplished. I shall give at the end of this chapter an idea of the method employed, in order to succeed in these exact determinations ; we will first satisfy our curiosity, and learn at what distance the nearest stars are from us.

The nearest star is in the southern constellation of the Centaur; it is the star a. According to the most recent researches, it is distant from us 211,300 times the distance from here to the Sun. A few years ago, it was believed to be further, but more exact determinations have definitely established that it is not beyond the distance just mentioned.

It is very difficult, if not impossible, to figure to oneself such distances, and to comprehend them, it is necessary for our mind to associate with the idea of space, the idea of time ; to travel in some way along this line, and to estimate its length by time. For small distances, we do the

106 Marvels of the Heavens.

same on the Earth. If, for example, it is said that it is 310 miles from Paris to Strasburg, we with difficulty fig! re this distance at first sight ; but by associating the idea of the time necessary to pass through it with a given velocity, by learning that an express train going at the rate of 44 miles per hour, arrives there in seven hours, we represent to ourselves the road traversed. This method, useful for terrestrial distances, is necessary for celestial ones : we shall also measure space by time ; only, instead of the velocity of a train, we shall take that of light, which travels at the rate of 136,000 miles per second.

Well, to traverse the distance which separates us from our neighbour a of the Centaur, our courier takes three years and eight months. If the mind wishes to follow it, it must not jump with the twinkling of an eye from the departure to the arrival, otherwise it would no longer have the slightest idea of the distance, it is necessary to represent to itself the direct path of the luminous ray, and to associate itself with this path, which it must imagine to travel 186,000 miles during the first second of route, dating from its de- parture ; then 186,000 miles for the second second, which makes 372,000 miles ; then again 186,000 miles during the third, and so on without stopping for three years and eight months.

If we give ourselves this trouble, it will enable us to understand the enormous value of the number ; otherwise, as it exceeds every number which the mind is accustomed to use, it will not have any meaning and will remain un- comprehended.

Our nearest star is a of the Centaur. The one whose distance places it immediately after, is a star situated in another region of the sky, in the constellation of the Swan. This is our second nearest ; which does not prevent it being nearly three times more distant from us than the first. The distances of ten stars have been calculated. The following are the nearest : The first column of numbers represents the

The Number of the Stars.

107

number of radii of the terrestrial orbit (distance from the Earth to the Sun) which must be laid out in line, one from the other, to reach the star ; the second column in- dicates the number of years light takes to traverse the distance :

ec of the Centaur

u of the Swan

Vega, * of Lyra

Sirius, « of the Great Dog..

<* of the Great Bear

Arcturus, u. of Bootes

Pole Star

The Goat, « of Auriga

211,330 3 years 8 months.

550,920 9k years.

1,330,700 21 „

1,375,000 22 „

1,550,800 25 „

1.622,800 26 „

3,078,600 50 „

4,484,000 72 „

These are the nearest stars. Most of the stars whose distances have been calculated are some of the brightest in the heavens, and are among those of the first and second mag- nitude. It may be asked if it be possible, by comparison, to determine the probable distance of the regions where the least magnitudes shine. This is a curious question, which Arago tried to solve and on which he reasoned as follows :

We take, for instance, from the foregoing list a mean star of the first magnitude, not Sirius, which exceeds all the others by its brilliancy, but Arcturus or Vega ; we ask ourselves to what distance must this star be transported in order that it may diminish in apparent brightness to the fourth magnitude, and we see that it is necessary to transport it to a distance four times greater than its present distance ; by withdrawing it to eight times the original distance, it would become from the fifth to the sixth order : in the mean, a star of the first magnitude transported to twelve times its actual distance, would still be visible to the naked eye, and its light would not fall below the sixth magnitude.

William Herschel tried to extend the scale of visibility which he had formed for the naked eye to telescopic observa- tions. He prepared a series of telescopes of gradually increasing

108 Marvels of the Heavens.

power, and for the subject of his observations he took the nebula of Perseus. There the eye could not distinguish any- star. If there were any. they were necessarily more feeble than the stars of the first magnitude would be, transported to twelve times their actual distance ; the small instrument showed a great number. Let us admit that, in this great number there are, which is probable, as bright stars as Arcturus, Vega, &c, these stars, in order to become just visible after their intensity was quadrupled, must be twice as far as the last stars visible to the naked eye, that is to say, twenty-four times further than Arcturus, Vega, &c.

The second instrument, which increased the light in the proportion of nine to one, and brought the objects three times nearer, discovered stars, the traces of which were not to be found in the first ; the intensities of the stars were such as Arcturus, Vega, &c, would become at thirty-six times their distance.

By coming gradually to the telescope of nine feet focal length, the observer perceived stars of intensity similar to what the stars of the first magnitude would appear at 344 times the distance which now separates them from us.

The eighteen-foot telescope extended its power to 900 times the distance of the stars of the first magnitude ; and it was evident that a more powerful telescope would have showed stars still more distant. To escape the numerical consequences that I am going to deduce from Herschel's results, it must be supposed that among the immense number of stars that each telescope of smaller power discovers, there does not exist one as brilliant as Arcturus or Vega of Lyra ; in a word, it must be admired that stars of the first mag- nitude only lie near our solar system. Such a supposition does not certainly deserve refutation.

There is no star of the first magnitude whose light reaches us in less than three years.

According to that, adds Arago, in conclusion, the light of the stars of different orders, in reality as large as Arcturus

The Number of the Stars. 109

Vega in Lyra, &c, arrives from such distances from the Earth that light could not pass through them, —

For stars of the second magnitude in less than . . 6 years

„ fourth magnitude 12 „

„ sixth magnitude 36 „

For the last stars visible with the nine- foot telescope 1042 „ For the last stars visible with the eighteen-foot

telescope 2700 „

The luminous rays which reach us from the stars relate to us then, if we may so express it, the ancient history of these bodies. But by what power did man arrive at the knowledge of the distances of the nearest stars ? In astronomy there are facts which surprise us by their grandeur, and which exceed the sphere of the habitual conceptions of man in such a way, that one is tempted to question them with doubt in spite of the affirmation of astronomers, and even to banish them to the rank of the deceitful pretensions with which science is sometimes surrounded, to impose on the vulgar. Of this number are the principal conquests of stellar astronomy, and particularly the determinations relative to the distance of the stars.

I shall endeavour to give an idea of the method which is employed to determine these distances, and by this explanation to remove the unfavourable idea still entertained by many of these perfectly established facts of modern astronomy.

A few instants' reflection will suffice to show, that if the Earth moves in space, during its annual course round the Sun, there must follow an apparent displacement of the other hodies in the sky. No one has looked from the window of a railway-carriage without seeing that the trees, houses, hills, and other objects which sprinkle the country, appear to move in an opposite direction to the path of the train, and that tt. nearest objects are those which appear to undergo the greatest displacement, whilst the most distant move more slowly, as far as the horizon, which remains nearly immovable. It

110 Marvels of the Heavens.

must then follow from the movement of the Earth in space, that the stars, situated in the region of the heavens which the Earth leaves behind at a certain time of the year, will appear nearer together, whilst the stars which the Earth approaches will appear to get further apart. This effect will be necessarily less as the distances of the stars become greater. If it were possible to measure the displacement undergone by a star in consequence of the movement of the Earth, we should have the distance of this star. For let the ellipse in Fi°\ 23 be the curve followed by the Earth in its annual path round the Sun, and let S be the Sun, T S T7 a diameter of the terrestrial orbit, and T and T" the position of the Earth at the two extremities of this diameter, that is to say, at six months' interval (as the Earth makes the entire passage in a year) ; lastly, let E be the star whose distance is to be measured.

Fig. 23. Measure of celestial distances.

When the Earth is situated at the point T, the angle S T E is measured, formed by the Sun, the Earth, and the star ; when the Earth is at T7, the angle S T7 E is measured. It is known that in every triangle the total of the three angles is equal to two right angles, that is, to 180°; there- S^e, if the total of the two observed angles, S T E and S T7 E, is found, and this total is deducted from 180°, the value of the angle at E will be obtained, the angle subtended at the star by the diameter of the terrestrial orbit. And this value will be as exact as if we could have been transported

The Number of the Stars. 1 1 1

to the star to- measure it directly. The half of this angle, that is, the angle S E T, is what is called ' the annual parallax' of the star E. Thus the annual parallax of a star is the angle under which an observer placed on the star would see the radius of the terrestrial orbit.

By always taking corresponding observations at two diametrically opposite points of the Earth's orbit in the course of the year, a great number of measures of the annual parallax will be obtained in this manner. In our example, and in our figure, the star is situated near the pole of the ecliptic; the operation is the same, although rather more simple for the other positions of the heavens. In practice, the measures of the angles 8 T E, S T' E, are obtained in an exact way, by comparing the successive positions of the star observed with that of a relatively fixed star which has no parallax. The great majority of stars are among the latter. Astronomical researches have proved that there is not a single star with its parallax equal to \" . They are all below it. To form an idea of this value, it must be under- stood that the circumference of astronomical circles used in observation is divided into 360 parts called degrees, each degree into 60 minutes, each minute into 60 seconds. This value of a second is so small that a spider's thread, placed in the field of view of the telescope, entirely hides the portion of the celestial sphere where the apparent movements of the stars are effected, a portion at most equal to 1".

The star which these observations have proved to be the nearest, is the star a of the Centaur ; its parallax is equal to 97 hundredths of a second (0,/#97). From the star a of the Centaur, the radius of the terrestrial orbit is then reduced to Of' '97. Now, in order that the length of any straight line seen be reduced as to appear only under the small angle of 1 second, it is necessary that this line be at a distance of 206,000 times its length, and in order to reduce it to 0"'97, it must be still further removed to 211,330 times itB length. These are mathematical data. Therefore the distance from

112 Marvels of the Heavens.

us of the star a of the Centaur is 211,330 times the radius of the terrestrial orbit, that is to say, 211,330 times 91 millions of miles.

This is the nearest star. Light travels for three years and eight months to come from it, to the Earth. The other near stars succeed each other, as we have seen, at greatei distances.

From the preceding it will be seen that these results, however prodigious they may appear at first sight, are due to mathematical methods of great simplicity. All the diffi- culty in this sort of determination consists in the extremely minute, long, and laborious observation of the slight dis- placement of the star in the heavens.

All these stars, vast as our Sun, separated from each other by such distances, succeeding each other in an endless manner in the immensity of space, are in motion in the heavens. Nothing is stationary in the universe, there is not a single atom of matter in absolute repose. The formidable forces with which matter is animated universally regulate its action. These movements of the suns of space are im- perceptible to our eyes, because they are performed at too great a distance ; but they are more rapid than any velocity we can observe on the Earth ; there are some stars which are carried away in space with a rapidity of fifty miles per second. To the eye which knew how to make abstrac- tion of time as of space, the sky would be a moving swarm of stars.

113

VI.

VARIABLE STARS— TEMPORAEY STARS— STARS SUDDENLY VISIBLE OR INVISIBLE.

' J'&ais seul pres des flots par une nuit d'etoiles. Pas un nuage aux cieux, sur les mers pas de voiles. Mes yeux plongeaient plus loin que l'e monde reel. Et les bois et les monts, et toute la nature, Semblaient interroger dans un confus murmure

Les flots des mers, les feux du ciel. Et les etoiles d'or, legions infinies, A voix haute, a voix basse, avec mille harmonies, Disaient en inclinant leurs couronnes de feu, Et les flots bleus, que rien ne gouverne et n'arrete, Disaient en recourbant Tecume de leur crete :

— C'est le Seigneur, le Seigneur Dieu ! '

Victoe Hugo, Orientales.

Of all the wonders which the telescope has revealed in the fields of space, not one has perhaps more right to the •astonishment of mortals than the existence of changing stars, periodically variable, whose light and colour undergo a periodicity of brightness ; at least, observers have not been more surprised at any telescopic revelation. Stars which, far from remaining fixed in an unchangeable light, see their brightness periodically die away and again revive ! — stars shining to-day with a splendid light will be invisible to-mor- row, and after to-morrow again revived ! The most daring imagination could scarcely invent such creatures ; and now even, when their existence has been well proved, the mind can scarcely accustom itself to realise it.

These are stars whose light undergoes a periodical variation, bringing it by turns to its maximum and its mini*

1 14 Marvels of the Heavens.

mum intensity. To figure to ourselves well in what this singular change consists, let us call to mind our Sun, and let us suppose it subjected to these variations. To-day it radiates the most transcendent flames, and pours down into the heated atmosphere floods of dazzling light ; for some days it preserves this same intensity ; but behold, the sky remain- ing clear as formerly, the light of the Sun gradually dies away from day to day : at the end of a week it has lost iialf its light ; at the end of fifteen days it can be looked at stead- fastly, and then it still fades, becomes pale and dull, only sending a wan light to the Earth. We tremble for its days, and we ask ourselves with the translator of Plutarch : —

( Le Dieu qui du neant vient de tirer le monde Va-t-il le replouger dans une nuit profonde ? Le soleil, ce flambeau de la terre et des cieux, A-t-il vu pour jamais aneantir ses feux ? '

But it revives, and with it hope. The firot progress in its extinguished light is noticed ; it becomes whiter and more brilliant. The torch is relighted and increases from day to day; a week after its minimum intensity, it already sends forth a light and heat which bring to mind the solar focus. Its increase continues. And when a period equal to that of its decline has passed, the dazzling Sun will have regained all its power and grandeur. The Earth is inun- dated with the rays of its brilliant light and its fertilising heat. But it does not enjoy this splendour long, for already the Sun recommences its decreasing curve. And so on, con- tinually. The nature of this new Sun is periodical while the virtue of our preceding one was to preserve a permanent light and heat.

It may be imagined that these variations of light astonish the observer who contemplates them in the field of the telescope. The periods are of all lengths. For some stars, the thirtieth of the Hydra of Hevelius, for instance, the period is

Variable Stars. 115

more than 1 year, "being 494 days. It varies between the fourth magnitude and complete disappearance. The star % of the neck of the Swan, varies from the fifth to the eleventh magni- tude in a period of 404 days. Another star of which we have already spoken in the chapter on the constellations, o of the Whale, also called the Marvellous (Mira Ceti), varies in 334 days from the second magnitude to total disappearance. Other stars are regulated by more rapid variations. The star which passes most rapidly from its maximum to its minimum, is Algol in Medusa's Head, which we already know ((3 of Perseus). For in 1 day, 10 hours, and 24 minutes, it has finished its decrease ; in the same lapse of time it has reached its maximum : its period is only 2 days, 20 hours, 48 minutes. The star § of Cepheus varies in a period of 5 days, 8 hours, and 37 minutes, from the third to the fifth magnitude. It will be seen that these variations are themselves very vari- able, and that there are suns which pass with strange rapidity from their greatest to their smallest light. What are the prodigious forces which regulate these gigantic changes ? Science has not yet been able to determine this. Maupertuis said that variable stars were of the form of lenses, that they turned perpendicularly on themselves, and that they presented to us successively their edge and front. At the period when they presented the edge, their light was at the minimum ; and at the time when they presented their entire front, it was at their maximum. But do lens-like suns exist ? If the thing is possible, it is not proved. Not only are there stars whose light changes periodically, sometimes diminishing until they become completely invisible, although, in reality, they are not quite extinguished ; but there are again others whose light is, weakened never to be revived, and which for ever have dis- appeared from the sky. These are the extinguished stars of which the list is rather long. The astronomer, Ulugh -Beigh, stated, in the year 1437, that one star of Auriga, the eleventh of the Wolf, six stars, among which four of the thiH. magnitude near the Southern Fish, all marked in the

116 Marvels of the Heavens.

catalogues of Ptolemy and Abdurrahman-Suphi, were nc longer visible in bis time. In the seventeenth century, J. D. Cassini, and at the end of the eighteenth, W. Herschel, pointed out a great number of other stars which had com- pletely disappeared. These were systems for which the hour of the end of the world had struck.

Speaking of the end of the world, this dread is awakened in the inhabitants of the Earth, not when stars disappear from the firmament, for this is mostly noticed by astronomers, but rather when a new body is suddenly lighted up in the heavens. Indeed there are stars which suddenly appear. In the same year as the massacre of Saint Bartholomew, on the 11th of November, 1572, a magnificent star of the first magnitude suddenly appeared in the constellation of Cassiopea, effacing by its brilliancy the most beautiful stars in the sky. It remained for eighteen months, and disappeared never to return.

Astrologers said that this appearance was the same as that to the Magi at the birth of Jesus Christ, and concluded from it that the last judgment was near. Thirty-two years later another new star appeared in the constellation of Ser- pentarius. From the day of its appearance, the 10th of Octo- ber, 1604, according to Arago, it was white ; it surpassed stars of the first magnitude in brightness, also Mars, Jupiter, and Saturn, which were near it. Many compared it to Venus. Those who had seen the star in 1572 found that the new one exceeded it in brightness. It did not appear to become fainter in the second half of the month of October ; on the 9th of November, the twilight which effaced Jupiter did not pre- vent this star from being visible. On the 16th of November Kepler perceived it for the last time, but at Turin, when it reappeared in the east, at the end of December and at the beginning of January, its light was fainter ; it certainly sur- passed Antares, but was not equal to Arcturus. On the 20th March, 1605, it was smaller in appearance than Saturn, but it exceeded in brightness the stars of the third magnitude in Ophiuchus. On the 21st of April it seemed equal to the

Variable Stars. 117

shining star of the third magnitude in the knee of Ophiuchus. It diminished imperceptibly ; on the 8th of October it was still seen, but with difficulty, on account of the twilight. In March, 1606, it had become completely invisible.

These appearances, like all extraordinary phenomena, excited terror and awakened ideas, not to be stifled, of the conflagration of the world, the fall of the stars, and the end of time. One of the most memorable predictions is that in 1588, announced in emphatic Latin verse, of which the fol- lowing is a translation : —

' After one thousand five hundred years, dating from the con- ception of the Virgin, this eighty-eighth year will be strange and full of dread ; it will bring with it sad destinies. If, in this terrible year, the perverse world does not fall into dust, if the earth and seas are not annihilated, all the empires of the world will be overthrown, and affliction will oppress the human race.'

This prediction was later renewed in favour or disfavour of the seventeenth century, and the Mercure de France an- nounced the greatest revolutions for the year 1788. It then passedt or naving been found in the tomb of Regiomontanus. Authors did not think how right they were to describe this memorable epoch under the title of revolution.

But while considering these predictions, the list of which would be longer than at first imagined, I cannot help relating the curious mystifications worked in 1524 by the German Astrologer StofBer. According to him, on the 20th of February of that year, the conjunction of the planets in the Fishes must produce a universal deluge. Astrologers gave faith to it like the common herd : the sinister news soon traversed the world, and they prepared themselves to see the universe pass from time into eternity. ' All the provinces of Gaul,' says an author of that period, ' were in strange fright and doubt of a universal inundation, and such that our fathers had not seen, or was known by historians or others, by means of which men and women were in great fear. And many removed from their low dwelling-places, and found

118 Marvels of the Heavens.

higher spots, made provision of meal and other matters, and had processions and general and public prayers, that it might please God to have pity on His people.'

Fear seized on a great many minds. Those who lived near the sea or rivers left their abodes, and sold, at immense losses. doubtless to unbelievers, their properties and goods. At Toulouse, another Noah constructed a ship to serve as an ark to his family and friends, — and, probably, also to a few- couples of animals. This was not the only case. Accord- ing to the account of the historian, Bodin, ' There were many infidels, who made arks to save themselves, although God's promise and oath, never again to drown man by a deluge, was preached to them.' Many and man}7 a time the prediction was given out, and, sad to say, it always found the same number of believers, although each time the event gave it a positive denial. In 1584, the fear caused by an announce- ment of this kind was so great that the churches were unable to contain those who sought refuge in them ; a great number made their wills without reflecting that it was useless if all the world was to perish ; and others gave their goods to the priests, in the hope that their prayers would delay this day of judgment. I believe that as long as the world remains it will fear its dissolution.

These singular stars which are suddenly lighted up in the heavens, to be extinguished soon after — these variable suns which pass through all degrees of light, and seem, like Castor and Pollux, to have received as a destiny an everlasting transitory movement from life to death and death to life, little suspect the terrors which they so innocently cause to spring up among men. What unknown power presides over these variations of light and heat ? What influence on the planetary worlds which circulate round these bodies is of so strange a nature? What thought regulates these movements, and what hand constructs beings born to live in harmony with such systems? What distance separates terrestrial nature, where years follow each other by a permanent law, and bring

Variable Stars. 119

back successively the same phenomena, from those worlds where such prodigious variations take place ? The mind is astonished with these questions and cannot answer them. Towards the end of the night, when sunrise began to cause the stars to fade, the English poet Kirke White expressed his astonishment in these terms : —

* Ye many twinkling stars, who yet do hold Your brilliant places in the sable vault Of night's dominions ! — planets, and central orbs Of other systems ; — big as the burning Sun Which lights this nether globe, — yet to our eye Small as the glow-worm's lamp ! — to you I raise My lowly orisons, while, all-bewildered, My vision strays o'er your ethereal hosts ; Too vast, too boundless, for our narrow minds, Warped with low prejudices, to unfold, And sagely comprehend ; thence, higher soaring, Through ye I raise my solemn thoughts to Him, The mighty Founder of this wondrous maze, The great Creator ! — Him, who now sublime, Wrapt in the solitary amplitude Of boundless space, above the rolling spheres, Sits on his silent throne, and meditates.

' Thou, proud man, look upon yon starry vault, Survey the countless gems which richly stud The Night's imperial chariot ; — telescopes Wilr show thee myriads, more innumerable Than the sea sand ; each of those little lamps To the great source of light, the central sun, Round which some other mighty sisterhoods Of planets travel, every planet stock'd With living beings impotent as thee. Now, proud man ! now, where is thy greatness fled ? What art thou in the scale of universes ? Less, less than nothing ! Yet of thee the God Who built this wondrous frame of worlds is careful,

. As well as of the mendicant who begs The leavings of thy table.'

120 Marvels of the Heavens.

VII.

DISTANT UNIVERSES— DOUBLE, MULTIPLE, AND COLOURED SUNS.

* Pax dela l'infini des cieux, Je vis encore une etendue Ou des soleils mysterieux, Qui se cacbent a notre vue, Illuminent d'autres mortels. La notre terre est inconnue, La sont d'immenses archipels Dont les humains, sans se connaitre, Adorent tous le meme Maitre, Chacun sur differents autels.'

The wonders we have just reviewed become insignificant before those which we approach. Here, what we call natural is quite overthrown. Our observation, ideas formed by expe- rience, classification, and judgment in that which concerns the works of nature, have no longer the least application. We are really in another world, strange, improbable, and un- natural to us. Life, the forces which sustain it, light, heat, electricity, the periods of days and nights, seasons, years, the visible and invisible world, all are transformed. Here we are on the surface of celestial globes, illuminated by many suns, of all magnitudes, lights, colours, and by moons with many- coloured discs. Nothing like it has been seen on the earth : are these truly our worlds ? — are these not other universes ?

Let us, then, sum up the studies we have made on the nature of these worlds in our panorama,* and let us observe

* See Annualre du Cosmos for the year 1865.

Distant Universes. 121

the essential types of the astonishing diversity which contrasts them from ours.

The white light of our Sun pours its dazzling rays from the azure height, and, thanks to the transparent atmosphere in which a thousand reflections form a real reservoir of light, all the objects which clothe or people the surface of the globe are enveloped in this light. Nevertheless, this white light is not simple. It contains in its rays all possible colours ; and bodies, instead of appearing to us clothed with a. uniform whiteness, absorb certain colours of this complex ray and reflect others; it is this reflection which constitutes the coloration of these bodies. This depends, then, on the molecular agency of the reflecting surface, on its power of receiving certain rays of the spectrum and of repelling others. But all these colours constitute the original white — the one source of these various appearances.

It is now well to remember that this theory, applicable to the organic world, receives still more considerable import- ance when we consider the mode of coloration of organic substances. The beauty of plants, the diversity of the meadows, the gold of the fields, the whiteness of the lily, the scarlet, orange, azure, and the charming shades wThich form the richness of the flowers, the brilliancy of plumage of little tropical birds, the snowlike doves, the yellow fur of the desert lion, like the radiancy of flaxen hair : it is to the white light of our Sun that we must go for the explanation of these visible beauties — in him resides the source of the infinite shades which decorate the forms of nature.

Now let us, for an instant, suppose that, instead of a white sun, the source of all the light which inundates us, we had a dark blue sun. What a change is soon worked in nature ! The clouds lose their silvery whiteness and gold from their flakes, and spreading a darker vault under the heavens, all nature is covered with a coloured penumbra, while the beauti- ful stars remain in the noon-day sky ; the flowers lose the

122.

Marvels of the Heavens.

light of their brilliant dress ; the fields succeed each other in the mist as far as the invisible horizon ; a new day shines under the heavens.

The carnation of fresh cheeks loses its budding bloom, faces appear to be aged, and astonished humanity asks for the explanation of such a strange phenomenon. We know the rudiments of things so little and we hold so much to appear- ances, that the whole universe seems to us renewed by this slight modification of solar light.

How would it be if, instead of an indigo sun, following its apparent course with regularity, making the years and days certain by its own rule, a second sun suddenly arrived in addition to it, a scarlet sun continually disputing the empire of the world of colours with its partner ? Imagine at noon, at the moment when our blue sun spreads that shadowy light over nature which we have just described, the conflagra- tion of a resplendent orb kindling its flames in the east. Greenish silhouettes suddenly rise through the diffused light, and opposite each object a dark shadow cuts the blue light which spreads over the world. Later the red sun rises as the other sinks, and the objects are coloured, to the east with the red rays, to the west with the blue. Later still, as a fresh mid-day lights up the Earth, the first sun vanishes, and from that time nature is clothed with a scarlet fire. If we pass to the night, scarcely have the last rays of the purple sun faded away in the west, like distant Bengal fires, than a new sunrise appears opposite the azured glimmer of the cyclops with the blue eye.

Is it possible for the imagination of poets or the caprice of painters to create on the palette of fancy a more daring world of light than this one ? The foolish hand of chimera, throw- ing on its impressible sheet the odd colours of its will, can.it erect at hazard a more wonderful edifice than this ? Hegel said that ' all which is real is rational,' and ' all which is rational is real.' Yet this bold thought does not express the whole truth. There are many things which do not

Distant Universes. 123

appear to us rational, and which, nevertheless, exist in reality in the mimherless creations of space which surround us.

What we have just said respecting an Earth .ighted up by two suns of different colours, one being dark blue and the other scarlet, is not imaginary. In a beautiful calm, clear night take your glass and look at Perseus, this hero walking in the midst of the Milky Way, holding Medusa's head in his hand ; look at the star q, this is a world such as that of which we have just spoken. The, large star is of a beautiful red, the other of a dark blue. At what distance is this strange system situated ? no one can tell. It can only be stated that, at the rate of 186,000 miles per second, light takes more than a hundred years to reach us from thence.

But this is not the only system of the kind. That of y of Ophiuchus resembles it so much that they may be easily mistaken one for the other (at such a distance, it would indeed be excusable) only in the system of Ophiuchus the blue sun is not so dark as in the others. One star of the Dragon very much resembles the preceding, but then the large sun is of a deeper red, its small one blueish ; another again, r\ Argo, has its large sun blue and its less brilliant one dark red.

Thus we have our imaginary world realised in many parts of space. And perhaps there are human eyes who thus contemplate those wonders each day. Who knows ? — and the thing is very probable — perhaps they pay no attention to it, and from their cradle accustomed like us to the same sight, they do not appreciate the picturesque value of their abode. Thus are men constituted. The novel and unexpected alone affect them ; as to the natural, this seems but an eternal, necessary, and fortuitous state of blind nature, which does not deserve the trouble of being observed. If the people came thence to us, though acknowledging the simplicity of our little universe, they would not fail to observe it with surprise, and be astonished at our indifference.

124

Marvels of the Heavens.

It was doubtless, after having dreamt of these strange and distant worlds that Victor Hugo wrote the following stanzas : —

' S'il nous etait donne de faire Ce voyage demesure, Et de voler de sphere en sphere A ce grand soleil ignore ; Si, par un archange qui l'ainie, L'homme aveugle, fremissant, bleme, Dans les profondeurs du probleme, Vivant, pouvait etre introduit ; Si nous pouvions fuir notre centre, Et, forcant l'ombre on Dieu seul entre, Aller voir de pres dans leur antre Ces enormites de la nuit ;

' Ce qui t'apparaitrait te ferait trembler, ange ! Rien, pas de vision, pas de songe insense, Qui ne fut depasse par ce spectacle etrange ; Monde infernal, et d'un tel mystere tisse, Que son rayon fondrait nos chairs, cire vivante, Et qu'il ne resterait de nous dans Fepouvante Qu'un regard ebloui sous un front herisse. Tu verrais ! — un soleil, autour de lui des mondes, Centres eux-meme, ayant des lunes autour d'eux ; La, des formillement de spheres vagabondes ; La des globes jumeaux qui tournent deux-d-deux?

The suns which constitute these multiple systems differ therefore from ours by their coloration; and, among the whole of the bodies, a fresh variety again manifests itself. Coloured binary systems are not composed solely of the red and blue suns to which we have just alluded; the means have not been at fault, it is the same here as in the universality of the productions of nature ; it is from an inex- haustible source that it has drawn the richness and sumptu- ousness with which it has decorated its works.

Distant Universes. 125

For instance, the following is the beautiful system of y of Andromeda. The large central sun is orange, the small one which gravitates near it is emerald green. * What follows from the union of these two colours? The orange and the emerald ? Is not this an assortment full of youth, if this metaphor be permitted? A large and magnificent orange sun in the midst of the heavens ; then a bright emerald which gracefully joins its green radiations to the gold.

Then again, in Hercules, we have two suns, red and green ; in Berenice's Hair, one pale red, the other a clear green ; in Cassiopea, a red and a green sun : a fresh series of soft and charming shades.

Let us change the prospect ; to do this, it is only neces- sary to consider other systems. There is more variety amongst them than in all the changes which an optician can produce on the screen of a magic-lantern. Certain planetary universes lighted up by two suns have all the series of colours included under blue, and the brilliant shades of gold and purple which throw so much vivacity on this world are there unknown. It is in this category that are placed certain systems situated in the constellations of Andromeda, the Serpent, Ophiuchus, Berenice's Hair, &c. Others, again, only know red suns, like a double star of the Lion for in- stance. Some other systems are devoted to the blue and yellow, or at least are lighted up by a blue sun and a yellow sun, wdiich only give them a limited series of shades com- prised in the combinations of these primitive colours; such are the systems of the Whale, of Eridanus, one of which is straw colour and the other blue, the Giraffe, Orion, Unicorn, the Twins, Bootes, the large yellow and the greenish -blue of the Swan ; the small one is of an intense blue. WTe have, on the other hand, assortments of red and green ; as is seen in Cassiopea, Berenice's Hair, and Hercules.

Other stellar systems are nearer ours, in the sense, that

* Our author might have added that this green star is double, and is built up of one blue and one yellow star. — Tr.

126 Marvels of the Heavens.

one of the suns which illuminates them has, like ours, a white light, the source of all colours, whilst its neighbour throws a simple radiation on everything. For instance, in the worlds which revolve round the great sun a of the Ram; the large sun is white, but we constantly see in the heavens another smaller sun, whose blue reflection covers the objects exposed to its rays, as with a veil. The 26th of the Whale is in the same condition, and it is the same with a great number among the brightest stars. Such is the star % in the Swan's neck, which is besides one of the most remarkable of the variable stars, for in a period of 404 days the large white sun diminishes from the fifth to the eleventh magnitude and returns to its primitive state. To the worlds which gravitate round the principal sun in these binary systems, the original white light appears to give rise to the infinite varieties which wTe observe on the Earth, with the addition of a blue light constantly coming from the other sun ; but to the planets which gravitate round this one, it is the blue coloration which predominates, whilst the action of the more distant white sun is only secondary.

In the same way as there are white suns, accompanied with blue suns, some are also accompanied with red or yellow suns. But I must not dwell on this enumeration if I wish to review the whole host of the sky.

What a variety of light with two suns, one red and the other green, or one yellow and the other blue, must be expe- rienced on a planet which revolves round one or the other ; and what charming contrasts, and what magnificent alternations must arise from a red day and a green day, succeeded in turn with a white day and with darkness ! What nature is there ! . What unimaginable beauty clothes with unknown splendour these distant lands scattered in endless space ?

If like our Moon which gravitates round the globe, or like those of Jupiter and Saturn, which unite their mirrors on the dark hemisphere of these worlds, the invisible planets which are there poised are surrounded with satellites which con-

Distant Universes. 127

stantly accompany them ; what is the aspect of these moons, lighted by many suns ? That moon which rises from the luminous mountains is divided into differently-coloured quarters, one red, another blue ; this other only presents an increasing yellow ; that one is at its full, it is green, and appears suspended in the heavens like an immense fruit. A ruby moon, an emerald moon, an opal moon, what heavenly jewellery ! O night of the Earth, which modestly silvers our solitary moon, thou art very beautiful when the calm and pensive mind contemplates thee ! But what art thou beside nights illuminated by these wonderful moons ?

And what are eclipses of the Sun on these worlds ? Multiply suns and multiply moons, to what endless changes must your mutually-eclipsed lights give rise ? The blue sun and the yellow sun stand near each other; their combined light produces green on the surfaces illuminated by both of them, yellow or blue on those which receive only one light. Soon the yellow approaches the blue ; already it enters on its disc and the green spread over the world fades, and fades, until the moment when it expires, melted into the gold which pours in space its beautifying rays. A total eclipse colours the world with yellow. An annular eclipse presents a blue ring round a gold piece. By degrees, imperceptibly, the green revives and holds its empire.

Let us add to this phenomenon another which would be produced if a moon came over the beautiful middle of this golden eclipse, to cover the yellow sun itself and to plunge the world in obscurity, then follow the relations existing between its movement and that of the Sun, continuing to hide it after its departure from the blue disc and then to leave nature again fallen under the veil of a new azure. Let us again add, — but no, this is Nature's inexhaustible treasure ; however much we take from it it will not be impoverished.

I will terminate these descriptions by a graceful poem, ' The Song of the Stars,' by the American poet Bryant. These stanzas are in their proper place, after the harmonies