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seen. from our latitude, at all hours of the night, and may be traced out at almost any season of the year. Its mean declination is 60° N. and its right ascension 12°. It is on our meridian the 22d of November, but does not sensibly change its position for several days; for it should be remembered that the apparent motion of the stars becomes slower and slower, as they approximate the poles.

Cassiopeia is a beautiful constellation, containing 55 stars that are visible to the naked eye; of which five are of the 3d magnitude, and so situated as to form, with one or two smaller ones, the figure of an inverted chair.

"Wide her stars

Dispersed, nor shine with mutual aid improved;
Nor dazzle, brilliant with contiguous flame:
Their number fifty-five."

Caph, in the garland of the chair, is almost exactly in the equinoctial colure, 30° N. of Alpheratz, with which, and the Polar Star, it forms a straight line. [See note to Andromeda.] Caph is therefore on the meridian the 10th of November, and one hour past it on the 24th. It is the westernmost star of the bright cluster. Shedir*, in the breast, is the uppermost star of the five bright ones, and is 5° S. E. of Caph: the other three bright ones, forming the chair, are easily distinguished, as they meet the eye at the first glance.

There is an importance attached to the position of Caph that concerns the mariner and the surveyor. It is used, in connexion with observations on the Polar Star, for determining the latitude of places, and for discovering the magnetic variation of the needle.

It is generally supposed that the North Polar Star, so called, is the real immove able pole of the heavens; but this is a mistake. It is so near the true pole that it has obtained the appellation of the North Polar Star; but it is, in reality, more than a degree and a half distant from it, and revolves about the true pole every 24 hours, in a circle whose radius is 1° 35'. It will consequently, in 24 hours, be twice on the meridian, once above, and once below the pole; and twice at its greatest elongation E. and W. [See North Polar Star.]

The Polar Star not being exactly in the N. pole of the heavens, but one degree and 35 minutes on that side of it which is towards Caph, the position of the latter becomes important as it always shows on which side of the true pole the polar star is.

There is another important fact in relation to the position

Shedir, from El Seder, the Seder tree; a name given to this constellation by Ulugh Beigh.

When may it be seen from this latitude? When is it on our meridian? How is the motion of the stars affected as they approach the poles? How many principal stars in this constellation, and what is their appearance? Describe the situation of Caph. When is Caph on the meridian? What is the relative position of Shedir? Why is the Position of Caph important?

of this star. It is equidistant from the pole, and exactly opposite another remarkable star in the square of the Great Bear, on the other side of the pole. [See Megrez.] It also serves to mark a spot in the starry heavens, rendered memorable as being the place of a lost star. Two hundred and fifty years ago, a bright star shone 5° N. N. E. of Caph, where now is a dark void!

On the 8th of November, 1572, Tycho Brahe and Cornelius Gemma saw a star in the constellation of Cassiopeia, which became, all at once, so brilliant, that it surpassed the splendour of the brightest planets, and might be seen even at noonday! Gradually, this great brilliancy diminished, until the 15th of March, 1573, when, without moving from its place, it became utterly extinct.

Its colour, during this time, exhibited all the phenomena of a prodigious flame-first it was of a dazzling white, then of a reddish yellow, and lastly of an ashy paleness, in which its light expired. It is impossible, says Mrs. Somerville, to imagine any thing more tremendous than a conflagration that could be visible at such a distance. It was seen for sixteen months.

Some astronomers imagined that it would reappear again after 150 years; but it has never been discovered since. This phenomenon alarmed all the astronomers of the age, who beheld it; and many of them wrote dissertations concerning it.

Rev. Professor Vince, one of the most learned and pious astronomers of the age, has this remark:-"The disappearance of some stars may be the destruction of that system at the time appointed by the DEITY for the probation of its inhabitants; and the appearance of new stars may be the for mation of new systems for new races of beings then called into existence to adore the works of their Creator."

Thus, we may conceive the Deity to have been employed from all eternity, and thus he may continue to be employed for endless ages; forming new systems of beings to adore him; and transplanting beings already formed into happier regions, who will continue to rise higher and higher in their enjoyments, and go on to contemplate system after system through the boundless universe. LA PLACE says:-"As to those stars which suddenly shine forth with a very vivid light, and then immediately disappear, it is extremely probable that great conflagrations, produced by extraordinary causes, take place on their surface. This conjecture, continues he, is confirmed by their change of colour, which is analogous to that presented to us on the earth by those bodies which are set on fire and then gradually extinguished."

The late eminent Dr. Good also observes that-Worlds and systems of worlds

What memorable spot does Caph serve to mark out? Describe the phenomenon of the lost star. What does Mrs. Somerville say of it? How long was it seen? Has any thing been discovered of it since? How did this phenomenon affect the astronomers of the age? What does Vince say of the disappearance of some stars, and the new appearance of others? Repeat the observations of Dr. Good upon the subject of new stare appearing and disappearing.

re not only perpetually creating, but also perpetually disappearing. It is an txtraordinary fact, that within the period of the last century, not less than thir een stars, in different constellations, seem to have totally perished, and ten new ones to have been created. In many instances it is unquestionable, that the stars themselves, the supposed habitation of other kinds or orders of intelligent be. ings, together with the different planets by which it is probable they were sur. rounded, have utterly vanished, and the spots which they occupied in t' e heavens, have become blanks! What has befallen other systems, will assured'y befall our own. Of the time and the manner we know nothing, but the fact is incontrovertible; it is foretold by revelation; it is inscribed in the heavens; it is felt through the earth. Such is the awful and daily text; what then ought to be the comment?

The great and good Beza, falling in with the superstition of his age, attempted to prove that this was a comet, or the same luminous appearance which conducted the magi, or wise men of the East, into Palestine, at the birth of our Saviour and that it now appeared to announce his second coming!

About 60 N. W. of Caph, the telescope reveals to us a grand nebula of small stars, apparently compressed into one mass, or single blaze of light, with a great number of loose stars surrounding it.

HISTORY.-Cassiopeia was wife of Cepheus, king of Æthiopia, and mother of Andromeda. She was a queen of matchless beauty, and seemed to be sensible of it; for she even boasted herself fairer than Juno, the sister of Jupiter, or the Nereides-a name given to the sea nymphs. This so provoked the ladies of the sea that they complained to Neptune of the insult, who sent a frightful monster to ravage her coast, as a punishment for her insolence. But the anger of Neptune and the jealousy of the nymphs were not thus appeased. They demanded, and it was finally ordained that Cassiopeia should chain her daughter Andromeda, whom she tenderly loved, to a desert rock on the beach, and leave her exposed to the fury of this monster. She was thus left, and the monster approached; but just as he was going to devour her, Perseus killed him.

"The saviour youth the royal pair confess,

And with heav'd hands, their daughter's bridegroom bless."
Eusden's Ovid.

CEPHEUS

CEPHEUS is represented on the map as a king, in his royal robe, with a sceptre in his left hand, and a crown of stars upon his head. He stands in a commanding posture, with his left foot over the pole, and his sceptre extended towards Cassiopeia, as if for favour and defence of the queen.

"Cepheus illumes

The neighbouring heavens; still faithful to his queen,
With thirty-five faint luminaries mark'd."

This constellation is about 25 N. W. of Cassiopeia, near the 2d coil of Draco, and is on the meridian at 8 o'clock the 3d of November; but it will linger near it for many days. Like Cassiopeia, it may be seen at all hours of the night. when the sky is clear, for to us it never sets.

By reference to the lines on the map, which all meet in the pole, it will be evident that a star, near the pole, moves over a much less space in one hour, than

There is a remarkable nebula in this constellation; describe its situation and ap pearance. How is Cepheus represented? What is his posture? Who is the sou stellation situated?

one at the equinoctial; and generally, the nearer the pole, the nurrower the space, and the slower the motion.

The stars that are so near the pole may be better described by their polar distance, than by their declination. By polar distance, is meant the distance from the pole; and is what the declination wants of 90°.

In this constellation there are 35 stars visible to the naked eye; of these, there glitters on the left shoulder, a star of the 3d magnitude, called Alderamin, which with two others of the same brightness, 8° and 12° apart, form a slightly-curved line towards the N. E. The last, whose letter name is Gamma, is in the right knee, 19° N. of Caph, in Cassiopeia. The middle one in the line, is Alphirk, in the girdle. This star is one third of the distance from Alderamin to the pole, and nearly in the same right line.

It cannot be too well understood that the bearings, or direction of one star from another, as given in this treatise, are strictly applicable only when the former one is on, or near the meridian. The bearings given, in many cases, are not the least approximations to what appears to be their relative position; and in some, if relied upon, will lead to errours. For example:-It is said, in the preceding paragraph, that Gamma, in Cepheus, bears 19° N. of Caph in Cassiopeia. This is true, when Caph is on the meridian, but at this very moment, while the author is writing this line, Gamma appears to be 19° due west of Caph; and six months hence, will appear to be the same distance east of it. The reason is obvious; the circle which Cepheus appears to describe about the pole, is within that of Cassiopeia, and consequently when on the east side of the pole, will be within, or between Cassiopeia and the pole-that is, west of Cassiopeia. And for the same reason, when Cepheus is on the west side of the pole, it is between that and Cassiopeia, or east of it.

Let it also be remembered, that in speaking of the poie, which we shall have frequent occasion to do, in the course of this work, the North Polar Star, or an imaginary point very near it, is always meant; and not as some will vaguely apprehend, a point in the horizon, directly N. of us. The true pole of the heavens is always elevated just as many degrees above our horizon, as we are north of the Equator. If we live in 420 N. latitude, the N. pole will be 42° above our horizon. (See North Polar Star.)

There are also two smaller stars about 9° E. of Alderamin and Alphirk, with which they form a square; Alderamin being the upper, and Alphirk the lower one on the W. 8° apart. In the centre of this square there is a bright dot, or semi-visible star.

The head of Cepheus is in the Milky-Way, and may he known by three stars of the 4th magnitude in the crown, which form a small acute triangle, about 9° to the right of Alderamin. The mean polar distance of the constellation is 25°, while that of Alderamin is 28° 10'. The right ascension of the former is 338°; consequently, it is 220 E. of the equinoctial colure.

The student will understand that right ascension is reckoned on the equinoc. tial, from the first point of Aries, E., quite round to the same point again, which

How many, and what are the principal stars in it? Describe the last star in the curve. Describe the middle one. What four stars form a square in this constellation? Where is the head of Cepheus, and how may it be known? What is the mean polar distance of this constellation? How far, and which way is it from the equinoctia. colure?

Is 360°. Now 338°, measured from the same point, will reach the same point again, within 220; which is the difference between 360° and 338°. This rule. will apply to any other case

HISTORY.-This constellation immortalizes the name of the king of Æthiopia. The name of his queen was Cassiopeia. They were the parents of Andromeda, who was betrothed to Perseus. Cepheus was one of the Argonauts who accompanied Jason on his perilous expedition in quest of the golden fleece. Newton supposes that it was owing to this circumstance that he was placed in the heavens; and that not only this, but all the ancient constellations, relate to the Argonautic expedition, or to persons some way connected with it. Thus, he observes that as Musæus, one of the Argonauts, was the first Greek who made a celestial sphere, he would naturally delineate on it those figures which had some reference to the expedition. Accordingly, we have on our globes to this day, the Golden Ram, the ensign of the ship in which Phryxus fled to Colchis, the scene of the Argonautic achievements. We have also the Bull with brazen hoofs, tamed by Ja. con; the Twins, Castor and Pollux, two sailors, with their mother Leda, in the form of a Swan, and Argo, the ship itself; the watchful Dragon Hydra, with the Cup of Medea, and a raven upon its carcass, as an emblem of death; also Chiron, the Master of Jason, with his Altar, and Sacrifice; Hercules, the Argonaut, with his club, his dart, and vulture, with the dragon, crab and lion which he slew; and Orpheus, one of the company, with his harp. All these, says Newton, refer to the Argonauts.

Again; we have Orion, the son of Neptune, or, as some say, the grandson of Minos, with his dogs, and hare, and river, and scorpion. We have the story of Perseus in the constellation of that name, as well as in Cassiopeia, Cepheus, An dromeda and Cetus; that of Calisto and her son Arcas, in Ursa Major; that of Icareus and his daughter Erigone, in Bootes and Virgo. Ursa Minor relates to one of the nurses of Jupiter; Auriga, to Erichthonius; Ophiuchus, to Phorbas Sagittarius, to Crolus, the son of one of the Muses; Capricorn, to Pan, and Aquarius to Ganymede. We have also Ariadne's crown, Bellerophon's horse, Neptune's dolphin, Ganymede's eagle, Jupiter's goat with her kids, the asses of Bacchus, the fishes of Venus and Cupid, with their parent, the southern fish. These, according to Deltoton, comprise the Grecian constellations mentioned by the poet Aratus; and all relate, as Newton supposes, remotely or immediately, to the Argonauts.

It may be remarked, however, that while none of these figures refer to any transactions of a later date than the Argonautic expedition, yet the great disa greement which appears in the mythological account of them, proves that their invention must have been of greater antiquity than that event, and that these constellations were received for some time among the Greeks, before their poets referred to them in describing the particulars of that memorable exhibition.

CHAPTER II.

DIRECTIONS FOR TRACING THE CONSTELLATIONS WHICH ARE ON THE MERIDIAN IN DECEMBER.

ARIES.

THE RAM. Twenty-two centuries ago, as Hipparchus n forms us, this constellation occupied the first sign in the ecliptic, commencing at the vernal equinox. But as the constellations gain about 50 on the equinox, at every revolution of the heavens, they have advanced in the ecliptic nearly 310 beyond it, or more than a whole sign: so that the Fishes now

What was the position of Aries in the ecliptic, 22 centuries ago?

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