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The brightest of the two upper stars, on the left, is called Algorab, and is situated in the E. wing of the Crow; it has nearly the same declination S. that the Dog-star has, and is on the meridian about the 13th of May. It is 21 E. of Alkes in the Cup, 1410 S. W. of Spica Virginis, a brilliant star of the 1st magnitude to be described in the next chapter. Beta, on the back of Hydra and in the foot of the Crow, is a star of the 3d magnitude, nearly 7° S. of Algorab. It is the brightest of the two lower stars, and on the left. The righthand lower one is a star of the 4th magnitude, situated in the neck, marked Epsilon, about 6° W. of Beta, and may be known by a star of the same magnitude situated 20 below it, in the eye, and called Al Chiba. Epsilon is 213° S. of the vernal equinox, and if a meridian should be drawn from the pole through Megrez, and produced to Epsilon Corvi, it would mark the equinoctial colure.
Gamma in the W. wing, is a star of the 3d magnitude, 310 W. of Algorab, and is the upper righthand one in the square. It is but 1 E. of the equinoctial colure.
10° E. of Beta is a star of the 3d magnitude, in the tail of Hydra, marked Gamma; these two, with Algorab, form nearly a right angled triangle, the right angle being at Beta.
STORY.-The Crow, it is said, was once of the purest white, but was changed for tale-bearing to its present colour. A fit punishinent for such a fault 1
"The raven once in snowy plumes was drest,
Fair as the guardian of the capitol,
Soft as the Swan; a large and lovely fowl;
His tongue, his prating tongue, had changed him quite,
According to Greek fable, the Crow was made a constellation by Apollo. This god being jealous of Coronis, (whom he tenderly loved.) the daughter of Phie gyas and mother of Esculapius, sent a crow to watch her behaviour; the bird perceived her criminal partiality for Ischys the Thessalian, and immediately acquainted Apollo with her conduct, which so fired his indignation that he lodged an arrow in her breast, and killed her instantly.
"The god was wroth; the colour left his look,
To reward the crow, he placed her among the constellations.
Others say that this constellation takes its name from the daughter of Coronæus, king of Phocis, who was transformed into a crow by Minerva, to rescue the maid from the pursuit of Neptune. The following, from an eminent Latin poet of the Augustine age, is her own account of the metamorphosis as translated into English verse by Mr. Addison :-
'For as my arms I lifted to the skies,
I saw black feathers from my fingers rise:
Describe the position of Algorab. How does its declination compare with that of Sirius? What are its distance and direction from Alkes and Spica Virginis? Describe the situation of Bett. Describe the situation of the righthand lower star. What is the distance of Epsilon from the vernal equinox, and how may the equinoctial colure be traced out by it? What are the magnitude and position of Gamma? Of Beta?
I strove to fling my garment on the ground;
My garment turned to plumes, and girt me round:
Sunk in the sand, but skimm'd along the shore;
To be the chaste Minerva's virgin bird."
THE VIRGIN. This is the sixth sign, and seventh constellation in the ecliptic. It is situated next east of Leo, and about midway between Coma Berenices on the N. and Corvus on the S. It occupies a considerable space in the heavens, and contains, according to Flamsted, one hundred and ten stars, including one of the 1st, six of the 3d, and ten of the 4th magnitudes. Its mean declination is 5° N., and its mean right ascension is 195°. Its centre is therefore on the meridian about the 23d of May.
The sun enters the sign Virgo, on the 23d of August, but does not enter the constellation before the 15th of September. When the sun is in this sign, the earth is in Pisces; and vice versa.
Spica Virginis, in the ear of corn* which the virgin holds in her left hand, is the most brilliant star in this constellation, and situated nearly 15° E. N. E. of Algorab in the Crow, about 35° S. E. of Denebola, and nearly as far S. S. W. of Arcturus-three very brilliant stars of the 1st magnitude that form a large equilateral triangle, pointing to the S. Arcturus and Denebola are also the base of a similar triangle on the north, terminating in Cor Caroli, which, joined to the former, constitutes the Diamond of Virgo. The length of this figure, from Cor Caroli on the north to Spica Virginis on the south, is 50°. Its breadth, or shorter diameter, extending from Arcturus on the east, to Denebola on the west, is.3540. Spica may otherwise be known by its solitary splendour, there being no visible star near it except one of the 4th magnitude, situated about 1° below it, on the left.
The position of this star in the heavens, has been determined with great exactness for the benefit of navigators. It
*In the Egyptian Zodiac, Isis, whose place was supplied by Virgo, was represented with three ears of corn in her hand. According to the Egyptian mythology, Isis was said to have dropped a sheaf of corn, as she fled from Typhon, who, as he continued to pursue her, scattered it over the heaven The Chinese call the Zodiac the yellow roud, as resembling a path over which the ripened ears of corn are scattered.
What is the relative position of Virgo among the signs and constellations of the ecliptic? How is it situated? How many stars does it contain, and how large are the principal ones? What are its mean declination and right ascension? When is the centre of the constellation on the meridian? Describe the principal star in Virgo. What are the distance and direction of Virgo from Algorab, Denebola and Arcturus? What are the magnitude and appearance of these three stars, and what figure do they form? How may Spica be otherwise distinguished? Why has its position been determined with great exactness?
is one of the stars from which the moon's distance is taken for determining the longitude at sea. Its situation is highly favourable for this purpose, as it lies within the moon's path, and little more than 20 below the earth's orbit.
Its right ascension being 1990, it will come to our meridian at 9 o'clock about the 28th of May, in that point of the heavens where the sun is at noon about the 20th of October.
Vindemiatrix, is a star of the 3d magnitude, in the right arm, or northern wing of Virgo, and is situated nearly in a straight line with, and midway between Coma Berenices, and Spica Virginis. It is 1910 S. W. of Arcturus, and about the same distance S. E. of Coma Berenices, and forms with these two a large triangle, pointing to the south. It bears also 18° S. S. E. of Denebola, and comes to the ineridian about 23 minutes before Spica Virginis.
Zeta, is a star of the 3d magnitude 1110 N. of Spica, and very near the equinoctial. Gamma, situated near the left side, is also a star of the 3d magnitude, and very near the equinoctial. It is 13° due west of Zeta, with which and Spica it forms a handsome triangle. Eta, is a star of the 3d magnitude, in the southern wing, 50 W. of Gamma, and but 210 E. of the autumnal equinox.
Beta, called also Zavijava, is a star of the 3d magnitude, in the shoulder of the wing, 740 W. of Eta, with which and Gamma, it forms a line near the Earth's orbit, and parallel to it. Beta, Eta, Gamma and Spica, forin the lower and longer side of a large spherical triangle whose vertex is in Beta. The other stars in this figure may be easily traced by means of the map. About 13° E. of Spica, there are two stars of the 4th magnitude, 3° apart, which mark the foot of Virgo. These two stars are on nearly the same meridian with Arcturus, and culminate nearly at the same time. The lower one, marked Lambda, is on the south, and but 80 W. of the principal star in Libra. Several other stars of the 3d magnitude lie scattered about in this constellation, and may be traced out by the map, "Her lovely tresses glow with starry light; Stars ornament the bracelet on her hand; Her vest in ample fold, glitters with stars: Beneath her snowy feet they shine; her eyes Lighten, all glorious, with the heavenly rays,
But first the star which crowns the golden sheaf."
HISTORY.-The famous zodiac of Dendera, as we have already noticed, commences with the sign Leo; but another zodiac, discovered among the ruins at Estne, in Egypt, commences with Virgo; and from this circumstance, some have argued, that the regular precession of the equinoxes established a date to this at least 2000 years older than that at Dendera. The discoveries of Champollion, however, render it probable that this ancient relic of astrology at Estne was erected during the reign of the Emperor Claudius. and consequently did not precede the one at Dendera more than fourteen years.
Of this, however, we may be certain: the autumnal equinox now corresponds with the first degree of Virgo; and, consequently, if we find a zodiac in which the summer solstice was placed where the autumnal equinox now is, that zodiac carries us back 90° on the ecliptic; this divided by the annual precession 501", must fix the date at about 6450 years ago. This computation, according to the chronology of the Sacred writings, carries us back to the earliest ages of the human species on earth, and proves, at least, that astronomy was among the first studies of mankind. The most rational way of accounting for this zodiac, says Jamieson, is to ascribe it to the family of Noah; or perhaps to the patriarch himself, who constructed it for the benefit of those who should live after the deluge, and who preserved it as a monument to perpetuate the actual state of the heavens immediately subsequent to the creation.
Fable represents the ancient Egyptians as believing that the yearly and regu lar inundations of the Nile proceeded from the abundant tears which Isis shed,
Why is its situation favourable for taking the moon's distance? When does it pass our meridian? Describe the situation of Vindemiatrix. Describe the figure which it forms with other stars in the same neighbourhood. What are its distance and bearing from Denebola? Describe Zeta. Describe Gamma. Describe the position of Eta Decribe the position of Beta. What geometrical figure may be formed of the stars in this neighbourhood?
for the loss of Osiris, whom Typhon had basely murdered. By confounding the simple allegory of the learned with the mythological creed of the vulgar, the historical account furnished us respecting Isis, becomes perplexed and unintelligible. Perhaps with the following key, we may unlock the mystery:-The sun in Leo, was adorned as the god Osiris; in Virgo, it was worshipped as his sister Isis; at its passage into Scorpio, the terrible reign of Typhon commenced. Columella fixes the transit of the sun into Scorpio, on the 13th of the calends of November; and this period nearly corresponds with that in which Osiris was feigned to have been slain by Typhon, and the death of Orion was to have been occasioned by the sting of a scorpion. When Scorpio begins to rise, Orion sets; when Scorpio comes to the meridian, Leo begins to set:-Typhon then reigns, Osiris is slain, and his sister follows him to the tomb weeping. The traditions allot the sign Virgo to Naphtali, whose standard had for its symbol, a tree "bearing goodly branches."
Thus mythology, in describing the physical state of the world. invented a symbolical language which personified inanimate objects; and the priests reduced the whole of their noblest science to fables, which the people believed as true histories representing the moral condition of mankind during the first ages of civil government.
According to the ancient poets, this constellation represents the virgin Astræa, the goddess of justice, who lived upon the earth during the golden age; but being offended at the wickedness and impiety of mankind during the brazen and iron ages of the world, she returned to heaven, and was placed among the constellations of the zodiac, with a pair of scales (Libra) in one hand and a sword in the other.
Hesiod, who flourished nearly a thousand years before the birth of our Saviour, and later writers, mention four ages of the world; the golden, the silver, the brazen, and the iron age. In the beginning of things, say they, all men were happy, and all men were good; the earth brought forth her fruits without the labour of man; and cares, and wants, wars and diseases, were unknown. But this happy state of things did not last long. To the golden age, the silver age succeeded; to the silver, the brazen; and to the brazen, the iron. Perpetual spring no longer reigned; men continually quarrelled with each other; crime succeeded to crime; and blasphemy and murder stained the history of every day. In the golden age, the gods did not disdain to mix familiarly with the sons of men. The innocence, the integrity and brotherly love which they found among us, were a pleasing spectacle even to superior natures; but as mankind degenerated, one god after another deserted their late beloved haunts; Astræa lingered the last; but finding the earth steeped in human gore, she herself flew away to the celestial regions.
"Victa jacet pietas; et virgo cæde madentes
"Faith flees, and piety in exile mourns;
And justice, here oppress'd, to heaven returns."
Some, however, maintain, that Erigone was changed into the constellation Virgo. The death of her father Icarius, an Athenian, who perished by the hands of some peasants, whom he had intoxicated with wine, caused a fit of despair, in which Erigone hung herself; and she was afterwards, as it is said, placed among the signs of the zodiac. She was directed by her faithful dog Mæra to the place where her father was slain. The first bough on which she hung herself, breaking, she sought a stronger, in order to effect her purpose. "Thus once in Marathon's impervious wood, Erigone beside her father stood,
When hastening to discharge her pious vows,
She loos'd the knot, and cull'd the strongest boughs."
ASTERION ET CHARA; VEL CANES VENATICI. THE GREYHOUNDS.-This modern constellation, embracing two in one, was made by Hevelius out of the unformed stars What is the origin of the constellation called the Greyhounds?
of the ancients which were scattered between Bootes on the east, and Ursa Major on the west, and between the handle of the Dipper on the north, and Coma Berenices on the south.
These Hounds are represented on the celestial sphere as being in pursuit of the Great Bear, which Bootes is hunting round the pole of heaven, while he holds in his hand the leash by which they are fastened together. The northern one is called Asterion, and the southern one, Chara.
The stars in this group are considerably scattered, and are principally of the 5th and 6th magnitudes; of the twenty-five stars which it contains, there is but one sufficiently large to engage our attention. Cor Caroli, or Charles's Heart, so named by Sir Charles Scarborough, in memory of King Charles the First, is a star of the 3d magnitude, in the neck of Chara the Southern Hound.
When on the meridian, Cor Caroli is 1710 directly S. of Alioth, the third star in the handle of the Dipper, and is so nearly on the same meridian that it culininates only one minute and a half after it. This occurs on the 20th of May.
A line drawn from Cor Caroli through Alioth will lead to the N. polar star. This star may also be readily distinguished by its being in a straight line with, and midway between Benetnasch, the first star in the handle of the Dipper, and Coma Berenices: and also by the fact that when Cor Caroli is on the ineridian, Denebola bears 28° S. W., and Arcturus 260 S. E. of it, forining with these two stars a very large triangle, whose vertex is at the north; it is also at the northern extremity of the large Diamond, already described.
The remaining stars in this constellation are too small, and too much scattered to excite our interest.
DIRECTIONS FOR TRACING THE CONSTELLATIONS WHICH ARE ON THE MERIDIAN IN JUNE.
THE BEAR-DRIVER is represented by the figure of a huntsman in a running posture, grasping a club in his right hand, and holding up in his left the leash of his two greyhounds, Asterion and Chara, with which he seems to be pursuing the Great Bear round the pole of the heavens. He is thence called Arctophylax, or the "Bear-Driver.”
* Pronounced Bo-o'-tes.
How are the Greyhounds represented? By what names are they distinguished? What are the magnitudes of the stars which compose this group, and how are they situated with respect to each other? Describe the principal star. When on the meridian what is its situation with regard to Alioth? How is Cor Caroli situated with respect to the polar star? How may this star be otherwise readily distinguished? What large geometrical figure does it form with two other bright stars in its vicinity? How is the constellation Bootes represented? Why is Bootes called the Bear-Driver?