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tre not only perpetually creating, but also perpetually disappearing. It is an Extraordinary fact, that within the period of the last century, not less than thireen 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 beings, together with the different planets by which it is probable they were surrounded, have utterly vanished, and the spots which they occupied in the heavens, have become blanks! What has befallen other systems, will assuredly 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."
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.)
The neighbouring heavens; still faithful to his queen,
This constellation is about 250 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? Whes the constellation situated?
one at the equinoctial; and generally, the nearer the pole, the narrower 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, 190 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 pole, 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 ap prehend, 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. 80 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 be 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 equinoctial, 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 equinoctial colure?
is 360°. Now 338°, measured from the same point, will reach the same point again, within 22°; 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 Ethiopia. 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 Jason; 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, Andromeda 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.
DIRECTIONS FOR TRACING, THE CONSTELLATIONS WHICH ARE ON THE MERIDIAN IN DECEMBER.
THE RAM. Twenty-two centuries ago, as Hipparchus informs us, this constellation occupied the first sign in the ecliptic, commencing at the vernal equinox.) But as the constellations gain about 5€// on the equinox, at every revolution of the heavens, they have advanced in the ecliptic nearly 31° 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?
occupy the same place in the Zodiac, that Aries did, in the time of Hipparchus; while the constellation Aries is now in the sign Taurus, Taurus in Gemini, and Gemini in Cancer, and so on.
ARIES is therefore now the second constellation in the Zodiac. It is situated next east of Pisces, and is midway between the Triangles and the Fly on the N. and the head of Cetus on the S. It contains 66 stars, of which, one is of the 2d, one of the 3d, and two of the 4th magnitudes.)
"First, from the east, the Ram conducts the year;
It is readily distinguished by means of two bright stars in the head, about 4° apart, the brightest being the most northeasterly of the two. The first, which is of the 2d magnitude, situated in the right horn, is called Alpha Arietis, or simply Arietis; the other, which is of the 3d magnitude, lying near the left horn, is called Sheratan, and may be known by another star of the 4th magnitude, in the ear, 140 S. of it, called Mesarthim, which is the first star in this constellation.
Arietis and Sheratan, are one instance out of many, where stars of more than ordinary brightness are seen together in pairs, as in the Twins, the Little Dog, &c., the brightest star being commonly on the east.
The position of Arietis (affords important facilities to nautical science. Difficult to comprehend as it may be, to the unlearned, the skilful navigator who should be lost upon an unknown sea, or in the midst of the Pacific ocean, could, by measuring the distance between Arietis and the Moon, which often passes near it, determine at once not only the spot he was in, but his true course and distance to any known meridian or harbour on the earth.
(Lying along the moon's path, there are nine conspicuous stars that are used by nautical men for determining their longitude at sea, thence called nautical stars.)
These stars are (Arietis, Aldebaran, Pollux, Regulus, Spica Virginis, Antares, Áltair, Fomalhaut, and Markab
The true places of these stars, for every day in the year, are given in the Nau tical Almanac, a valuable work published annually by the English "Board of Admiralty," to guide mariners in navigating the seas. They are usually published two or three years in advance, for the benefit of long voyages.
That a man, says Sir John Herschel, by merely measuring the moon's apparent distance from a star, with a little portable instrument held in his hand, and
What is its present position? How is it now situated with respect to the surrounding constellations? What are the number and magnitude of its stars? How is this constellation readily distinguished? Describe the two bright stars in the head. For what purposes is the position of some of the stars in Arietis important? How many stars are used for determining longitude at sea, and where are they situated? By what general name are they called? Enumerate them
applied to his eye, even with so unstable a footing as the deck of a ship, shall say positively within five miles, where he is, on a boundless ocean, cannot but appear to persons ignorant of physical astronomy, an approach to the miraculous. And yet, says he, the alternatives of life and death, wealth and ruin, are daily and hourly staked, with perfect confidence, on these marvellous computations.
Capt. Basil Hall, of the royal navy, relates that he had sailed from San Blas on the west coast of Mexico, and after a voyage of 8000 miles occupying eighty-nine days, arrived off Rio Janeiro, having in this interval passed through the Pacific ocean, rounded Cape Horn, and crossed the South Atlantic without making any land or seeing a single sail on the voyage. Arrived within a few days' sail of Rio, he took a set of lunar observations, to ascertain his true position, and the bearing of the harbour, and shaped his course accordingly. I hove to," says
he," at 4 in the morning, till the day should break, and then bore up; for although it was hazy, we could see before us a couple of iniles or so. About 8 o'clock it became so foggy that I did not like to stand in farther, and was just bringing the ship to the wind again before sending the people to breakfast, when it suddenly cleared off, and I had the satisfaction of seeing the great Sugar-loaf rock, which stands on one side of the harbour's mouth, so nearly right ahead that we had not to alter our course above a point in order to hit the entrance of Rio. This was the first land we had seen for three months, after crossing so many seas, and being set backwards and forwards by innumerable currents and foul winds.'
Arietis comes to the meridian about (12 minutes after Sheratan, on the 5th December, near where the sun does in midsummer. Arietis, also, is nearly on the same meridian with Almaach in the foot of Andromeda, 19° N. of it, and culminates only four minutes after it. The other stars in this constellation are quite small, constituting that loose cluster which we see between the Fly on the north, and the head of Cetus on the south.
When Arietis is on the meridian, Andromeda and Cassiopeia are a little past the meridian, nearly over head, and Perseus with the head of Medusa, is as far to the east of it. Taurus and Auriga are two or three hours lower down; Orion appears in the S. E.. and the Whale on the meridian, just below Aries, while Pegasus and the Swan are seen half way over in the west.
The manner in which the ancients divided the Zodiac into 12 equal parts, was both simple and ingenious. Having no instrument that would measure time exactly, "They took a vessel, with a small hole in the bottom, and having filled it with water, suffered the same to distil, drop by drop, into another vessel set beneath to receive it, beginning at the moment when some star rose, and continuing till it rose the next following night, when it would have performed one complete revolution in the heavens. The water falling down into the receiver, they divided into 12 equal parts; and having twelve other small vessels in readi ness, each of them capable of containing one part, they again poured all the water into the upper vessel, and observing the rising of some star in the Zodiac, at the same time suffered the water to drop into one of the small vessels. And as soon as it was full, they removed it, and set an empty one in its place. Just as each vessel was full, they took notice what star of the Zodiac rose at that tine, and thus continued the process through the year, until the 12 vessels were filled."
Thus the Zodiac was divided into 12 equal portions, corresponding to the 12
When does Arietis pass the meridian? What other brilliant star is on the meridian nearly at the same time? When Aries is on the meridian, what other constellations are immediately in view? Describe the manner in which the ancients divided the Zodiac. At what point of the Zodiac did this division commence?