Astronomy with an Opera-glass Part 6

Careful observation detects a decided difference between its color and that of Betelgeuse, or Alpha Orionis, which is also a red star. It differs, too, from the brilliant red star of summer, Antares. Aldebaran has a trace of rose-color in its light, while Betelgeuse is of a very deep orange, and Antares may be described as fire-red. These shades of color can easily be detected by the naked eye after a little practice.

First compare Aldebaran and Betelgeuse, and glance from each to the brilliant white, or bluish-white, star Rigel in Orion's foot. Upon turning the eye back from Rigel to Aldebaran the peculiar color of the latter is readily perceived. Spectroscopic a.n.a.lysis has revealed the presence in Aldebaran of hydrogen, sodium, magnesium, calcium, iron, bis.m.u.th, tellurium, antimony, and mercury. And so modern discoveries, while they have pushed back the stars to distances of which the ancients could not conceive, have, at the same time, and equally, widened the recognized boundaries of the physical universe and abolished forever the ancient distinction between the heavens and the earth. It is a plain road from the earth to the stars, though mortal feet can not tread it.

[Ill.u.s.tration: THE HYADES.]

Keeping in mind that in our little picture of the Hyades the top is north, the right hand west, and the left hand east, the reader will be able to identify the princ.i.p.al stars in the group. Aldebaran is readily recognized, because it is the largest of all. The bright star near the upper edge of the picture is Epsilon Tauri, and its sister star, forming the point of the [V], is Gamma Tauri. The three brightest stars between Epsilon and Gamma, forming a little group, are the Deltas, while the pair of stars surrounded by many smaller ones, half-way between Aldebaran and Gamma, are the Thetas. These stars present a very pretty appearance, viewed with a good gla.s.s, the effect being heightened by a contrast of color in the two Thetas. The little pair southeast of Aldebaran, called the Sigmas, is also a beautiful object. The distance apart of these stars is about seven minutes of arc, while the distance between the two Thetas is about five and a half minutes of arc. These measures may be useful to the reader in estimating the distances between other stars that he may observe. It will also be found an interesting test of the eye-sight to endeavor to see these stars as doubles without the aid of a gla.s.s. Persons having keen eyes will be able to accomplish this.

North of the star Epsilon will be seen a little group in the ear of the Bull (see cut, "The Golden Horns of Taurus"), which presents a brilliant appearance with a small gla.s.s. The southernmost pair in the group are the Kappas, whose distance apart is very nearly the same as that of the Thetas, described above; but I think it improbable that anybody could separate them with the naked eye, as there is a full magnitude between them in brightness, and the smaller star is only of magnitude 6.5, while sixth-magnitude stars are generally reckoned as the smallest that can be seen by the naked eye. Above the Kappas, and in the same group in the ear, are the two Upsilons, forming a wider pair.

Next we come to the Pleiades:

"Though small their size and pale their light, wide is their fame."

In every age and in every country the Pleiades have been watched, admired, and wondered at, for they are visible from every inhabited land on the globe. To many they are popularly known as the Seven Stars, although few persons can see more than six stars in the group with the unaided eye. It is a singular fact that many of the earliest writers declare that only six Pleiades can be seen, although they all a.s.sert that they are seven in number. These seven were the fabled daughters of Atlas, or the Atlantides, whose names were Merope, Alcyone, Celaeno, Electra, Taygeta, Asterope, and Maia. One of the stories connected with them is that Merope married a mortal, whereupon her star grew dim among her sisters. Another fable a.s.sures us that Electra, unable to endure the sight of the burning of Troy, hid her face in her hands, and so blotted her star from the sky. While we may smile at these stories, we can not entirely disregard them, for they are intermingled with some of the richest literary treasures of the world, and they come to us, like some old keepsake, perfumed with the memory of a past age. The mythological history of the Pleiades is intensely interesting, too, because it is world-wide. They have impressed their mark, in one way or another, upon the habits, customs, traditions, language, and history of probably every nation. This is true of savage tribes as well as of great empires. The Pleiades furnish one of the princ.i.p.al links that appear to connect the beginnings of human history with that wonderful prehistoric past, where, as through a gulf of mist, we seem to perceive faintly the glow of a golden age beyond. The connection of the Pleiades with traditions of the Flood is most remarkable. In almost every part of the world, and in various ages, the celebration of a feast or festival of the dead, dimly connected by traditions with some great calamity to the human race in the past, has been found to be directly related to the Pleiades. This festival or rite, which has been discovered in various forms among the ancient Hindoos, Egyptians, Persians, Peruvians, Mexicans, Druids, etc., occurs always in the month of November, and is regulated by the culmination of the Pleiades. The Egyptians directly connected this celebration with a deluge, and the Mexicans, at the time of the Spanish conquest, had a tradition that the world had once been destroyed at the time of the midnight culmination of the Pleiades. Among the savages inhabiting Australia and the Pacific island groups a similar rite has been discovered. It has also been suggested that the j.a.panese feast of lanterns is not improbably related to this world-wide observance of the Pleiades, as commemorating some calamitous event in the far past which involved the whole race of man in its effects.

The Pleiades also have a supposed connection with that mystery of mysteries, the great Pyramid of Cheops. It has been found that about the year 2170 B. C., when the beginning of spring coincided with the culmination of the Pleiades at midnight, that wonderful group of stars was visible, just at midnight, through the mysterious southward-pointing pa.s.sage of the Pyramid. At the same date the then pole-star, Alpha Draconis, was visible through the northward-pointing pa.s.sage of the Pyramid.

Another curious myth involving the Pleiades as a part of the constellation Taurus is that which represents this constellation as the Bull into which Jupiter changed himself when he carried the fair Europa away from Phoenicia to the continent that now bears her name. In this story the fact that only the head and fore-quarters of the Bull are visible in the sky is accounted for on the ground that the remainder of his body is beneath the water through which he is swimming. Here, then, is another apparent link with the legends of the Flood, with which the Pleiades have been so strangely connected, as by common consent among many nations, and in the most widely separated parts of the earth.

With the most powerful field-gla.s.s you may be able to see all of the stars represented in our picture of the Pleiades. With an ordinary opera-gla.s.s the fainter ones will not be visible; yet even with such a gla.s.s the scene is a remarkable one. Not only all of the "Seven Sisters," but many other stars, can be seen twinkling among them. The superiority of Alcyone to the others, which is not so clear to the naked eye, becomes very apparent. Alcyone is the large star below the middle of the picture with a triangle of little stars beside it. To the left or east of Alcyone the two most conspicuous stars are Atlas and Pleione.

The latter--which is the uppermost one--is represented too large in the picture. It requires a sharp eye to see Pleione without a gla.s.s, while Atlas is plainly visible to the unaided vision, and is always counted among the naked-eye Pleiades, although it does not bear the name of one of the mythological sisters, but that of their father. The bright star below and to the right of Alcyone is Merope; the one near the right-hand edge of the picture, about on a level with Alcyone, is Electra. Above, or to the north of Electra, are two bright stars lying in a line pointing toward Alcyone; the upper one of these, or the one farthest from Alcyone, is Taygeta, and the other is Maia. Above Taygeta and Maia, and forming a little triangle with them, is a pair of stars which bears the name of Asterope. About half-way between Taygeta and Electra, and directly above the latter, is Celaeno.

[Ill.u.s.tration: THE PLEIADES.]

The naked-eye observer will probably find it difficult to decide which he can detect the more easily, Celaeno or Pleione, while he will discover that Asterope, although composed of two stars, as seen with a gla.s.s, is so faint as to be much more difficult than either Celaeno or Pleione.

Unless, as is not improbable, the names have become interchanged in the course of centuries, the brightness of these stars would seem to have undergone remarkable changes. The star of Merope, it will be remembered, was said to have become indistinct, or disappeared, because she married a mortal. At present Merope is one of those that can be plainly seen with the naked-eye, while the star of Asterope, who was said to have had the G.o.d Mars for her spouse, has faded away until only a gla.s.s can show it. It would appear, then, that notwithstanding an occasional temporary eclipse, it is, in the long run, better to marry a plain mortal than a G.o.d. Electra, too, who hid her eyes at the sight of burning Troy, seems to have recovered from her fright, and is at present, next to Alcyone, the brightest star in the cl.u.s.ter. But, however we may regard those changes in the brightness of the Pleiades which are based upon tradition, there is no doubt that well-attested changes have taken place in the comparative brilliancy of stars in this cl.u.s.ter since astronomy became an exact science.

Observations of the proper motions of the Pleiades have shown that there is an actual physical connection between them; that they are, literally speaking, a flight of suns. Their common motion is toward the southwest, under the impulse of forces that remain as yet beyond the grasp of human knowledge. Alcyone was selected by Madler as the central sun around which the whole starry system revolved, but later investigations have shown that his speculation was not well founded, and that, so far as we can determine, the proper motions of the stars are not such as to indicate the existence of any common center. They appear to be flying with different velocities in every direction, although--as in the case of the Pleiades--we often find groups of them a.s.sociated together in a common direction of flight.

Still another curious fact about the Pleiades is the existence of some rather mysterious nebulous ma.s.ses in the cl.u.s.ter. In 1859 Temple discovered an extensive nebula, of a broad oval form, with the star Merope immersed in one end of it. Subsequent observations showed that this strange phenomenon was variable. Sometimes it could not be seen; at other times it was very plain and large. In Jeaurat's chart of the Pleiades, made in 1779, a vast nebulous ma.s.s is represented near the stars Atlas and Pleione. This has since been identified by Goldschmidt as part of a huge, ill-defined nebula, which he thought he could perceive enveloping the whole group of the Pleiades. Many observers, however, could never see these nebulous ma.s.ses, and were inclined to doubt their actual existence. Within the past few years astronomical photography, having made astonis.h.i.+ng progress, has thrown new light upon this mysterious subject. The sensitized plate of the camera, when applied at the focus of a properly constructed telescope, has proved more effective than the human retina, and has, so to speak, enabled us to see beyond the reach of vision by means of the pictures it makes of objects which escape the eye. In November, 1885, Paul and Prosper Henry turned their great photographing telescope upon the Pleiades, and with it discovered a nebula apparently attached to the star Maia. The most powerful telescopes in the world had never revealed this to the eye. Yet of its actual existence there can be no question. Their photograph also showed the Merope nebula, although much smaller, and of a different form from that represented by its discoverer and others. There evidently yet remains much to be discovered in this singular group, and the mingling of nebulous matter with its stars makes Tennyson's picturesque description of the Pleiades appear all the more life-like:

"Many a night I saw the Pleiads, rising through the mellow shade, Glitter like _a swarm of fire-flies tangled in a silver braid_."

The reader should not expect to be able to see the nebulae in the Pleiades with an opera-gla.s.s. I have thought it proper to mention these singular objects only in order that he might be in possession of the princ.i.p.al and most curious facts about those interesting stars.[C]

[Footnote C: The Henry Brothers have continued the photographic work described above, and their later achievements are even more interesting and wonderful. They have found that there are many nebulous ma.s.ses involved in the group of the Pleiades, and have photographed them. One of the most amazing phenomena in their great photograph of the Pleiades is a long wisp or streak of nebulous matter, along which eight or nine stars are strung in a manner which irresistibly suggests an intimate connection between the stars and the nebula. This recalls the recent (August, 1888) discovery made by Prof. Holden, with the great Lick telescope, concerning the structure of the celebrated ring nebula in Lyra, which, it appears, is composed of concentric ovals of stars and nebulous stuff, so arranged that we must believe they are intimately a.s.sociated in a most wonderful community.]

Orion will next command our attention. You will find the constellation in Map No. 19:

"Eastward beyond the region of the Bull Stands great Orion; whoso kens not him in cloudless night Gleaming aloft, shall cast his eyes in vain To find a brighter sign in all the heaven."

To the naked eye, to the opera-gla.s.s, and to the telescope, Orion is alike a mine of wonders. This great constellation embraces almost every variety of interesting phenomena that the heavens contain. Here we have the grandest of the nebulae, some of the largest and most beautifully colored stars, star-streams, star-cl.u.s.ters, nebulous stars, variable stars. I have already mentioned the positions of the princ.i.p.al stars in the imaginary figure of the great hunter. I may add that his upraised arm and club are represented by the stars seen in the map above Alpha ([alpha]) or Betelgeuse, one of which is marked Nu ([nu]), and another, in the k.n.o.b of the club, Chi ([chi]). I have also, in speaking of Aldebaran, described the contrast in the colors of Betelgeuse and Beta ([beta]) or Rigel. Betelgeuse, it may be remarked, is slightly variable.

Sometimes it appears brighter than Rigel, and sometimes less brilliant.

It is interesting to note that, according to Secchi's division of the stars into types, based upon their spectra, Betelgeuse falls into the third order, which seems to represent a type of suns in which the process of cooling, and the formation of an absorptive envelope or sh.e.l.l, have gone on so far that we may regard them as approaching the point of extinction. Rigel, on the other hand, belongs to the first order or type which represents suns that are probably both hotter and younger in the order of development. So, then, we may look upon the two chief stars of this great constellation as representing two stages of cosmical existence. Betelgeuse shows us a sun that has almost run its course, that has pa.s.sed into its decline, and that already begins to faint and flicker and grow dim before the on-coming and inevitable fate of extinction; but in Rigel we see a sun blazing with the fires of youth, splendid in the first glow of its solar energies, and holding the promise of the future yet before it. Rigel belongs to a new generation of the universe; Betelgeuse to the universe that is pa.s.sing. We may pursue this comparison one step farther back and see in the great nebula, which glows dimly in the middle of the constellation, between Rigel triumphant and Betelgeuse languis.h.i.+ng, a still earlier cosmical condition--the germ of suns whose infant rays may illuminate s.p.a.ce when Rigel itself is growing dim.

[Ill.u.s.tration: THE SWORD OF ORION AND THE GREAT NEBULA.]

Turn your gla.s.s upon the three stars forming the Belt. You will not be likely to undertake to count all the twinkling lights that you will see, especially as many of them appear and disappear as you turn your attention to different parts of the field. Sweep all around the Belt and also between the Belt and Gamma ([gamma]) or Bellatrix. According to the old astrologers, women born under the influence of the star Bellatrix were lucky, and provided with good tongues. Of course, this was fortunate for their husbands too!

Below the Belt will be seen a short row of stars hanging downward and representing the sword. In the middle of this row is the great Orion nebula. The star Theta ([theta]) involved in the nebula is multiple, and the position of this little cl.u.s.ter of suns is such that, as has been said, they seem to be feeding upon the substance of the nebula surrounding them. Other stars are seen scattered in different parts of the nebula. This phenomenon can be plainly seen with an opera-gla.s.s.

Our picture of the Sword of Orion shows its appearance with a good field-gla.s.s. With such a gla.s.s several fine test-objects will be found in the Sword. One of the best of these is formed by the two five-pointed stars seen in the picture close together above the nebula. No difficulty will be encountered in separating these stars with a field-gla.s.s, but it will require a little sharp watching to detect the small star between the two and just above the line joining them. So, the bending row of faint stars above and to the right of the group just described will be found rather elusive as individuals, though easily glimpsed as a whole.

Of the great nebula itself not much detail can be seen. Yet by averting the eyes the extension of the nebulous light in every direction from the center can be detected and traced, under favorable circ.u.mstances, to a considerable distance. The changes that this nebula certainly has undergone in the brilliancy, if not in the form, of different parts of it, are perhaps indications of the operation of forces, which we know must prevail there, and whose tendency can only be in the direction of condensation, and the ultimate formation of future suns and worlds. Yet, as the appearance of the nebula in great telescopes shows, we can not expect that the processes of creation will here produce a h.o.m.ologue of our solar system. The curdled appearance of the nebula indicates the formation of various centers of condensation, the final result of which will doubtless be a group of stars like some of those which we see in the heavens, and whose common motion shows that they are bound together in the chains of reciprocal gravitation. The Pleiades are an example of such a group.

Do not fail to look for a little star just west of Rigel, which, with a good opera-gla.s.s, appears to be almost hidden in the flas.h.i.+ng rays of its brilliant companion. If you have also a field-gla.s.s, after you have detected this shy little twinkler with your opera-gla.s.s, try the larger gla.s.s upon it. You will find then that the little star originally seen is not the only one there. A still smaller star, which had before been completely hidden, will now be perceived. I may add that, with telescopes, Rigel is one of the most beautiful double stars in the sky, having a little blue companion close under its wing. Run your gla.s.s along the line of little stars forming the lion's skin or s.h.i.+eld that Orion opposes to the onset of Taurus. Here you will find some interesting combinations, and the star marked on the map [pi]^6 will especially attract your eye, because it is accompanied, about fifteen minutes to the northwest, by a seventh-magnitude star of a rich orange hue.

Look next at the little group of three stars forming the head of Orion.

Although there is no nebula here, yet these stars, as seen with the naked eye, have a remarkably nebulous look, and Ptolemy regarded the group as a nebulous star. The largest star is called Lambda ([lambda]); the others are Phi ([phi]) one and two. An opera-gla.s.s will show another star above ([lambda]), and a fifth star below [phi]^2 which is the farthest of the two Phis from Lambda. It will also reveal a faint twinkling between [lambda] and [phi]^1. A field-gla.s.s shows that this twinkling is produced by a pretty little row of three stars of the eighth and ninth magnitudes.

In fact, Orion is such a striking object in the sky that more than one attempt has been made to steal away its name and subst.i.tute that of some modern hero. The University of Leipsic, in 1807, formally resolved that the stars forming the Belt and Sword of Orion should henceforth be known as the constellation of Napoleon. As if to offset this, an Englishman proposed to rename Orion for the British naval bull-dog Nelson. But "Orion armed" has successfully maintained his name and place against all comers. As becomes the splendor of his constellation, Orion is a tremendous hero of antiquity, although it must be confessed that his history is somewhat shadowy and uncertain, even for a mythological story. All accounts agree, however, that he was the mightiest hunter ever known, and the Hebrews claimed that he was no less a person than Nimrod himself.

[Ill.u.s.tration: MAP 20.]

The little constellations of Lepus and Columba, below Orion, need not detain us long. You will find in them some pretty combinations of stars.

In Lepus is the celebrated "Crimson Star," which has been described as resembling a drop of blood in color--a truly marvelous hue for a sun--but, as it is never brighter than the sixth magnitude, and from that varies down to the ninth, we could hardly hope to see its color well with an opera-gla.s.s. Besides, the observer would have difficulty in finding it.

We will now turn to the constellation of Canis Major, represented in Map No. 20. Although, as a constellation, it is not to be compared with the brilliant Orion, yet, on account of the unrivaled magnificence of its chief star, Canis Major presents almost as attractive a scene as its more extensive rival. Everybody has heard of Sirius, or the Dog-Star, and everybody must have seen it flas.h.i.+ng and scintillating so splendidly in the winter heavens, that to call it a first-magnitude star does it injustice, since no other star of that magnitude is at all comparable with it. Sirius, in fact, stands in a cla.s.s by itself as the brightest star in the sky. Its light is white, with a shade of green, which requires close watching to be detected. When it is near the horizon, or when the atmosphere is very unsteady, Sirius flashes prismatic colors like a great diamond. The question has been much discussed, as to whether Sirius was formerly a red star. It is described as red by several ancient authors, but it seems to be pretty well established that these descriptions are most of them due to a blunder made by Cicero in his translation of the astronomical poem of Aratus. It is not impossible, though it is highly improbable, that Sirius has changed color.

So intimately was Sirius connected in the minds of the ancient Egyptians with the annual rising of the Nile, that it was called the Nile-star.

When it appeared in the morning sky, just before sunrise, the season of the overflowing of the great river was about to begin, and so the appearance of this star was regarded as foretelling the coming of the floods. The dog-days got their name from Sirius, as they occur at the time when that star rises with the sun.

Your eyes will be fairly dazzled when you turn your gla.s.s upon this splendid star. By close attention you will be able to perceive a number of faint stars, mere points by comparison, in the immediate neighborhood of Sirius. There are many interesting objects in the constellation. The star marked Nu ([nu]) in the map is really triple, as the smallest gla.s.s will show. Look next at the star-group 41 M. The cloud of minute stars of which it is composed can be very well seen with a field-gla.s.s or a powerful opera-gla.s.s. The star 22 is of a very ruddy color that contrasts beautifully with the light of Epsilon ([epsilon]), which can be seen in the same field of view with an opera-gla.s.s. Between the stars Delta ([delta]) and [omicron] and [omicron] there is a remarkable array of minute stars, as shown in the accompanying cut. One never sees stars arranged in streams or rows, like these, without an irresistible impression that the arrangement can not be accidental; that some law must have been in operation which a.s.sociated them together in the forms which we see. Yet, when we reflect that these are all suns, how far do we seem to be from understanding the meaning of the universe!

[Ill.u.s.tration: DELTA CANIS MAJORIS AND ITS NEIGHBORS.]

The extraordinary size and brilliancy of Sirius might naturally enough lead one to suppose that it is the nearest of the stars, and such it was once believed to be. Observations of stellar parallax, however, show that this was a mistake. The distance of Sirius is so great that no satisfactory determination of it has yet been made. We may safely say, though, that that distance is, at the least calculation, 50,000,000,000,000 miles. In other words, Sirius is about 537,000 times as far from the earth as the sun is. Then, since light diminishes as the square of the distance increases, the sun, if placed as far from us as Sirius is, would send us, in round numbers, 288,000,000,000 times less light than we now receive from it. But Sirius actually sends us only about 4,000,000,000 times less light than the sun does; consequently Sirius must s.h.i.+ne 288,000,000,000/4,000,000,000 = 72 times as brilliantly as the sun. If we adopt Wollaston's estimate of the light of Sirius, as compared with that of the sun, viz., 1/20,000,000,000, we shall still find that the actual brilliancy of that grand star is more than fourteen times as great as that of our sun.

But as observations on the companion of Sirius show that Sirius's ma.s.s is fully twenty times the sun's, and since the character of Sirius's spectrum indicates that its intrinsic brightness, surface for surface, is much superior to the sun's, it is probable that our estimate of the star's actual brilliancy, as compared with what the sun would possess at the same distance, viz., seventy-two times, is much nearer the truth. It is evident that life would be insupportable upon the earth if it were placed as near to Sirius as it is to the sun. If the earth were a planet belonging to the system of Sirius, in order to enjoy the same amount of heat and light it now receives, it would have to be removed to a distance of nearly 800,000,000 miles, or eight and a half times its distance from the sun. Its time of revolution around Sirius would then be nearly five and a half years, or, in other words, the year would be lengthened five and a half times.

But, as I have said, the estimate of Sirius's distance used in these calculations is the smallest that can be accepted. Good authorities regard the distance as being not less than 100,000,000,000,000 miles; in which case the star's brilliancy must be as much as 228 times greater than that of the sun! And yet even Sirius is probably not the greatest sun belonging to the visible universe. There can be little doubt that Canopus, in the southern hemisphere, is a grander sun than Sirius. To our eyes, Canopus is only about half as bright as Sirius, and it ranks as the second star in the heavens in the order of brightness. But while Sirius's distance is measurable, that of Canopus is so unthinkably immense that astronomers can get no grip upon it. If it were only twice as remote as Sirius, it would be equal to two of the latter, but in all probability its distance is much greater than that. And possibly even Canopus is not the greatest gem in the coronet of creation.

Sirius, as we saw when talking of Procyon (see Chapter I), is a double star. For many years after Bessel had declared his belief that the Dog-Star was subjected to the attraction of an invisible companion, telescopes failed to reveal the accompanying star.[D] Finally, in 1862, a new telescope that Alvan Clark had just finished and was testing, brought the hidden star into view. The suggestion that it may s.h.i.+ne by reflected light from Sirius has been made. In that case it must, of course, be a planet, but a planet of such stupendous magnitude that the imagination can scarcely grasp it; a planet probably as large as our sun, perhaps larger; a planet equal in size to more than a million earths! But, as was remarked of the faint stars in Alpha Capricornis, it is probable that the hypothesis of reflected light is not the true one.

More probably the companion of Sirius s.h.i.+nes with light of its own, though its excessive faintness in comparison with its bulk indicates that its condition must be very different from that of an ordinary star.

[D] The following extract from a letter by Bessel to Humboldt, written in 1844 (see "Cosmos," vol. iii, p. 186), is interesting, in view of the discoveries made since then: "At all events I continue in the belief that Procyon and Sirius are true double stars, consisting of a visible and an invisible star. No reason exists for considering luminosity an essential property of these bodies. The fact that numberless stars are visible is evidently no proof against the existence of an equally incalculable number of invisible ones. The physical difficulty of a change in the proper motion is satisfactorily set aside by the hypothesis of dark stars."

Readers of Voltaire will remember that the hero of his extraordinary story of "Micromegas" came from an imaginary planet circling around Sirius. Inasmuch as Voltaire, together with Dean Swift, ascribed two moons to Mars many years before they were discovered (probably suggested by a curiously mistaken interpretation by Kepler of an anagram in which Galileo had concealed his discovery of the ring of Saturn), it is all the more interesting that the great infidel should have imagined an enormous planet circling around the Dog-Star. But Voltaire went far astray when he ascribed a gigantic stature to his "Sirian." He makes Micromegas, whose world was 21,600,000 times larger in circ.u.mference than the earth, more than twenty miles tall, so that when he visited our little planet he was able to wade through the oceans and step over the mountains without inconvenience, and, when he had scooped up some of the inhabitants on his thumb-nail, was obliged to use a powerful microscope in order to see them. Voltaire should rather have gone to some of the most minute of the asteroids for his giant, for under the tremendous gravitation of such a world as he has described Micromegas himself would have been a fit subject for microscopic examination. But, however much we may doubt the stature of Voltaire's visitor from Sirius, we can not doubt the soundness of the conclusion at which he arrived, after having, by an ingenious arrangement, succeeded in holding a conversation with some earthly philosophers under his microscope, namely, that these infinitely little creatures possessed a pride that was almost infinitely great.

East and south of Canis Major, which, by-the-way, is said to represent one of Orion's hounds, is part of the constellation Argo, which stands for the s.h.i.+p in which Jason sailed in search of the golden fleece. The observer will find many objects of interest here, although some of them are so close to the horizon in our lat.i.tudes that much of their brilliancy is lost. Note the two stars [zeta] and [pi] near the lower edge of the map, then sweep slowly over the s.p.a.ce lying between them.

About half-way your attention will be arrested by a remarkable stellar arrangement, in which a beautiful half-circle of small stars curving above a larger star, which is reddish in color, is conspicuous. This neighborhood will be found rich in stars that the naked eye can not see.

Just below the star [eta], in Canis Major, is another fine group. The star [pi], which is deep yellow or orange, has three little stars above it, two of which form a pretty pair. The star [xi] has a companion, which forms a fine test for an opera-gla.s.s, and is well worth looking for. Look also at the cl.u.s.ter 93 M, just above and to the west of [xi].

The stars [mu] and [kappa] are seen double with an opera-gla.s.s.

The two neighboring cl.u.s.ters, 46 M and 38^8, are very interesting objects. To see them well, use a powerful field-gla.s.s. A "fiery fifth-magnitude star," as Webb calls it, can be seen in the field at the same time. The presence of the Milky-Way is manifest by the sprinkling of stars all about this region. In fact, the attentive observer will before this have noticed that the majority of the most brilliant constellations lie either in the Milky-Way or along its borders.

Ca.s.siopeia, as we saw, sits athwart the galaxy whose silvery current winds in and out among the stars of her "chair"; Perseus is aglow with its sheen as it wraps him about like a mantle of stars; Taurus has the tips of his horns dipped in the great stream; it flows between the s.h.i.+ning feet of Gemini and the head and shoulders of Orion as between starry banks; the peerless Sirius hangs like a gem pendent from the celestial girdle. In the southern hemisphere we should find the beautiful constellation of the s.h.i.+p Argo, containing Canopus, sailing along the Milky-Way, blown by the breath of old romance on an endless voyage; the Southern Cross glitters in the very center of the galaxy; and the bright stars of the Centaur might be likened to the heads of golden nails pinning this wondrous scarf, woven of the beams of millions of tiny stars, against the dome of the sky. Pa.s.sing back into the northern hemisphere we find Scorpio, Sagittarius, Aquila, the Dolphin, Cygnus, and resplendent Lyra, all strung along the course of the Milky-Way.

Turning now to the constellation Monoceros, we shall find a few objects worthy of attention. This constellation is of comparatively modern origin, having been formed by Bartschius, whose chief t.i.tle to distinction is that he married the daughter of John Kepler. The region around the stars 8, 13, and 17 will be found particularly rich, and the cl.u.s.ter 2^7 shows well with a strong gla.s.s. Look also at the cl.u.s.ter 50 M, and compare its appearance with that of the cl.u.s.ters in Argo.

With these constellations we finish our review of the stellar wonders that lie within the reach of so humble an instrument as an opera-or field-gla.s.s. We have made the circuit of the sky, and the hosts that illumine the vernal heavens are now seen advancing from the east, and pressing close upon the brighter squadrons of winter. Their familiar figures resemble the faces of old friends whom we are glad to welcome.

These starry acquaintances never grow wearisome. Their interest for us is as fathomless as the deeps of s.p.a.ce in which they s.h.i.+ne. The man never yet lived whose mind could comprehend the full meaning of the wondrous messages that they flash to us upon the wings of light. As we watch them in their courses, the true music of the spheres comes to our listening ears, the chorus of creation--faint with distance, for it is by slow approaches that man draws near to it--chanting the grandest of epics, the Poem of the Universe; and the theme that runs through it all is the reign of law. Do not be afraid to become a star-gazer. The human mind can find no higher exercise. He who studies the stars will discover--

"An endless fountain of immortal drink Pouring unto us from heaven's brink."