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tion of the earth. Dark spots, or large portions of the surface, less luminous than the rest, turned alternately in certain di rections either towards, or from us, will account for all the phenomena of periodical changes in the lustre of the stars, so satisfactorily, that we certainly need not look out for any other cause."
It is said, that the famous astronomer Lalande, who died at Paris in 1807, was wont to remain whole nights, in his old age, upon the Pont Neuf, to exhibit to the curious the variations in the brilliancy of the star Algol.
Nine degrees E. by N. from Algol, is the bright star Algenib, of the 2d magnitude, in the side of Perseus, which with Almaack, makes a perfect right angle at Algol, with the open part towards Cassiopeia. By means of this strikingly perfect figure, the three stars last mentioned may always be recognised without the possibility of mistaking them. Algenib may otherwise be readily distinguished by its being the brightest and middle one of a number of stars lying four and five degrees apart, in a large semicircular form, curving towards Ursa Major.
Algenib comes to the meridian on the 21st December, 15 minutes after Algol, at which time the latter is almost directly over head. When these two stars are on the meridian, that beautiful cluster, the Pleiades, is about half an hour E. of it; and in short, the most brilliant portion of the starry heavens is then visible in the eastern hemisphere. The glories of the scene are unspeakably magnificent; and the student who fixes his eye upon those lofty mansions of being, cannot fail to covet a knowledge of their order and relations, and to 66 reverence Him who made the Seven Stars and Orion
The Milky-Way around Perseus is very vivid, being undoubtedly a rich stratum of fixed stars, presenting the most wonderful and sublime phenomenon of the Creator's power and greatness.) (Kohler, the astronomer, observed a beautiful nebula near the face of Perseus, besides eight other nebulous clusters in different parts of the constellation.
The head and sword of Perseus are exhibited on the circumpolar map. That very bright star 23° E. of Algol, is Capella in the Charioteer.
HISTORY.-Perseus was the son of Jupiter and Danae. He was no sooner born than he was cast into the sea with his mother; but being driven on the coasts of one of the islands of the Cyclades, they were rescued by a fisherman, and carried to Polydectes, the king of the place, who treated them with great humanity, and intrusted them to the care of the priests of Minerva's Temple. His rising genius and manly courage soon made him a favourite of the gods. At a
How may Algenib be distinguished? When is it on the meridian? How long after Algol? When these two stars are on the meridian, what beautiful cluster is half an hour east of it? What is the general appearance of the eastern hemisphere at that time? What is the appearance of the Milky Way around Perseus? What nebulæ have been observed in this constellation?
great feast of Polydectes, all the nobles were expected to present the king with a superb and beautiful horse; but Perseus, who owed his benefactor much, not wishing to be thought less munificent than the rest, engaged to bring hini the head of Medusa, the only one of the three Gorgons who was subject to mortality. The names of the other two were Stheno and Euriale. They were represented with serpents wreathing round their heads instead of hair, having yellow wings and brazen hands; their bodies which grew indissolubly together, were covered with impenetrable scales, and their very looks had the power of turning into stones all those on whom they fixed their eyes.
To equip Perseus for this perilous enterprise, Pluto, the god of the infernal regions, lent him his helmet, which had the power of rendering the wearer invisible. Minerva the goddess of wisdom, furnished him with her buckler, which was as resplendent as a polished inirror; and he received from Mercury, wings for his feet, and a dagger made of diamonds. Thus equipped, he mounted into the air, conducted by Minerva, and came upon the monsters who, with the watchful snakes about their heads, were all asleep. He approached them, and with a courage which amazed and delighted Minerva, cut off with one blow Medusa's head. The noise awoke the two immortal sisters, but Pluto's helmet rendered Perseus invisible, and the vengeful pursuit of the Gorgons proved fruitless.
Perseus then made his way through the air, with Medusa's head yet reeking in his hand, and from the blood which dropped from it as he flew, sprang al those innumerable serpents that have ever since infested the sandy deserts of Lybia.
The victor Perseus, with the Gorgon head,
And from each drop envenomed serpents grew."
The destruction of Medusa rendered the name of Perseus immortal, and he was changed into a constellation at his death, and placed among the stars, with the head of Medusa by his side.
DIRECTIONS FOR TRACING THE CONSTELLATIONS WHICH ARE ON THE MERIDIAN IN JANUARY.
The constellations which pass our meridian in the months of January, February and March, present to us the most brilliant and interesting portion of the heavens; embracing an annual number of stars of the highest order and brightness, all so conspicuously situated, that the most inexperienced can easily trace them out.
THE BULL is represented in an attitude of rage, as if about to plunge at Orion, who seems to invite the onset by provo cations of assault and defiance. Only the head and shoulders of the animal are to be seen; but these are so distinctly
What is the comparative brilliancy of the constellations which pass the meridian in January, February and March? How is Taurus represented? What parts of the animal are to be seen?
marked that they cannot be mistaken. Taurus is now the second sign and third constellation of the Zodiac; but anterior to the time of Abraham, or more than 4000 years ago, the vernal equinox took place, and the year opened when the sun was in Taurus; and the Bull, for the space of 2000 years, was the prince and leader of the celestial host. The Ram succeeded next, and now the Fishes lead the year. The head of Taurus sets with the sun about the last of May, when the opposite constellation. the Scorpion is seen to rise in the S. E. (It is situated between Perseus and Auriga on the north, Gemini on the east, Orion and Eridanus on the south, and Aries on the west, having a mean declination of 16° N.
It contains 141 visible stars, including two remarkable clusters called the PLEIADES and HYADES. The first is now on the shoulder, and the latter in the face of the Bull.
The Pleiades, according to fable, were the seven daughters of Atlas and the nymph Pleione,* who were turned into stars, with their sisters the Hyades, on account of their amiable virtues and mutual affection.
Thus we every where find that the ancients, with all their barbarism and idolatry, entertained the belief that umblemished virtue and a meritorious life would meet their reward in the sky. Thus Virgil represents Magnus Apollo as bending from the sky to address the youth Iulus:
"Macte nova virtute puer; sic itur ad astra;
"Go on, spotless boy, in the paths of virtue; it is the way to the stars; offspring of the gods thyself so shalt thou become the father of gods."
Our disgust at their superstitions may be in some measure mitigated, by seriously reflecting, that had some of these personages lived in our day, they hadl been ornaments in the Christian church, and models of social virtue.
The names of the Pleiades are Alcione, Merone, Maia, Electra, Tayeta, Sterope and Celeno. Merope was the only one who married a mortal, and on that account her star is dim among her sisters.
Although but six of these are visible to the naked eye, yet Dr. Hook inforins us that, with a twelve feet telescope, he saw 78 stars; and Rheita affirms that he counted 200 stars in this small cluster.
The most ancient authors, such as Homer, Attalus, and Geminus, counted only six Pleiades; but Simonides, Varro, Pliny, Aratus, Hipparchus, and Ptolemy, reckon them seven in number; and it was asserted, that the seventh had been seen before the burning of Troy; but this difference might arise from the dif ference in distinguishing them with the naked eye.
* Dr. Hutton is of opinion that Atlas being the first astronomer who discovered these stars, called them by the names of the daughters of his wife Pleione.
What is the numerical order of Taurus among the signs and constellations of the Zodiac? What was its position in the Zodiac before the time of Abraham? How long did it continue to lead the celestial host? What constellation succeeded next? Where is Taurus now situated? How many stars does it contain? What remarkable clusters are in this constellation? Where are these placed? Mention the names of the Pleiades. Which of these seven stars is not seen, and why? Are these six all that can be seen through the telescope?
The Pleiades are so called from the Greek word, wheel, pleein, to sail; because, at this season of the year, they were considered "the star of the ocean" to the benighten mariner.* Alcyone, of the 3d magnitude, being the brightest star in this cluster, is sometimes called the light of the Pleiades. The other five are principally of the 4th and 5th magnitudes.
The Pleiades, or as they are more familiarly termed, the seven stars, come to the meridian/10 minutes before 9 o'clock, on the evening of the 1st of January, and may serve, in place of the sun, to indicate the time, and as a guide to the surrounding stars.
According to Hesiod, who wrote about 900 years before the birth of our Sa viour, the heliacal rising of the Pleiades took place on the 11th of May, about the time of harvest.
Thus, in all ages, have the stars been observed by the husbandman. for 66 signs and for seasons."
Pliny says that Thales, the Miletan astronomer, determined the cosmical setting of the Pleiades to be 25 days after the autumnal equinox. This would make a difference between the setting at that time and the present, of 35 days, and as a day answers to about 59′ of the ecliptic, these days will make 34° 25'. This divided by the annual precision (501), will give 2465 years since the time of Thales. Thus does astronomy become the parent of chronology.
If it be borne in mind that the stars uniformly rise, come to the meridian, and set about four minutes earlier every succeeding night, it will be very easy to determine at what time the seven stars pass the meridian on any night subsequent or antecedent to the 1st of January. For example: at what time will the
* Virgil, who flourished 1200 years before the invention of the magnetic needle, says that the stars were relied upon, in the first ages of nautical enterprise, to guide the rude bark over the seas.
"Tunc alnos primum fluvii sensere cavatas;
Navita tum stellis numeros, et nomina fecit,
The same poet also describes Palinurus, the renowned pilot of the Trojan fleet, as "watching the face of the nocturnal heavens."
"Sidera cuncta notat tacito labentia cœ10,
Arcturum, pluviasque Hyadas, geminosque Triones,
Observe the stars, and notes their sliding course,
And bright Orion, arm'd witn ournish'd gold.'
Indeed, this sagacious pilot was once so intent in gazing upon the stars while at the helm, that he fell overboard, and was lost to his companions.
"Headlong he fell, and, struggling in the main,
From what circumstance do the Pleiades derive their name? What is the brightest of the Pleiades called? What is the size of the rest? When are the Pleiades on the meridian? How much earlier do the stars rise, come to the meridian, and set, every succeeding night?
seven stars culminate on the 5th January? Multiply the 5 days by 4 and take the result from the time they culminate on the 1st, and it will give 30 minutes after 8 o'clock in the evening.
The Pleiades are also sometimes called Vergilia, or the 66 Virgins of spring;" because the sun enters this cluster in the "season of blossoms," about the 18th of May. He who made them alludes to this circumstance when he demands of Job: "Canst thou bind the sweet influences of the Pleiades," &c.—[Job 38: 31.]
The Syrian name of the Pleiades is Succoth, or Su h-Benoth, derived from a Chaldaic word, which signifies "to speculate, to observe," and the "Men of Succoth," (2 Kings 17: 30.) have been thence considered observers of the
The Hyades are situated 11° S. E. of the Pleiades, in the face of the Bull, and may be readily distinguished by means of five stars so placed as to form the letter V. The most brilliant star is on the left, in the top of the letter, and called Aldebaran from which the moon's distance is computed.
"A star of the first magnitude illumes
His radiant head; and of the second rank.
Aldebaran is of Arabic origin, and takes its name from two words which signify, "He went before, or led the way"auding to that period in the history of astronomy when this star led up the starry host from the vernal equinox. It comes to the meridian at 9 o'clock on the 10th of January, or 481 minutes after Alcyone, on the 1st. When Aries is about 270 high, Aldebaran is just rising in the east. SO MANILIUS:—
"Thus when the Ram hath doubled ten degrees,
A line 150 E. N. E. of Aldebaran will point out a bright star of the 2d magnitude in the extremity of the northern horn, marked Beta or El Nath; (this star is also in the foot of Auriga, and is common to both constellations.) From Beta in the northern horn, to Zeta, in the tip of the southern horn, it is 80, in a southerly direction. This star forms a right angle with Aldebaran and Beta. Beta and Zeta, then, in the button of the horns, are in a line nearly north and south, 80 apart, with the brightest on the north. That very bright star 171⁄2° N. of Beta, is Capella, in the constellation Auriga.
*The ancient Greeks counted seven in this cluster:
"The Bull's head shines with seven refulgent flames,
At what time will the seven stars culminate on the 5th January? By what other names are they sometimes called, and why? What allusion is made to this cluster in the ancient Scriptures? Describe the situation and appearance of the Hyades. What is the brightest of them called? What is the origin of the word Aldebaran, and to what does it allude? When does Aldebaran culminate? Describe the position of Beta? What are the name and direction of the star in the southern horn? What is the relative position of these stars? What very bright star is seen 17° 30′ N. of Beta?