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or large portions of the surface less luminous than the rest, turned alternately in certain directions either toward, 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.
60. 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 recognized 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 overhead. 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 "reverence Him who made the Seven Stars and Orion."
61. 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.
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 favorite of the gods. At a 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 him 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 Euryale. 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 mirror; and he received from Mercury wings for his feet, and a dagger made
60. Algenib? How known? When on the meridian? Where, then, are the Pleiades? What the general aspect of the heavens? 61. Milky Way around Perseus? Observa tion of Kohler?
HISTORY.-Who was Perseus? What fate at birth, &c.?
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.
"In the mirror of his polished shield
And not one serpent by good chance awake;
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 all those innumerable serpents that have ever since infested the sandy deserts of Libya.
"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.
1. a PERSEI-A FINE DOUBLE STAR; R. A. 3h. 12m. 55s.; Dec. N. 49° 17′ 2′′. A 2%, brilliant lilac; B9, cinereous. This is Algenib, in the hero's left side.
2. B PERSEI, or Algol; R. A. 2h. 57m. 46s.; Dec. N. 41° 20'. A variable DOUBLE STAR. A 2 to 4, whitish; B 11, purple. The former varies in brightness periodically, from the 2d to the 4th magnitude, and back again to the 2d magnitude, period being 2d. 20h. 48m. 56s.; an object of great interest.
3. Y PERSEI-A WIDE UNEQUAL DOUBLE STAR in the hero's left shoulder; R. A. 2h, 58m. 14s.; Dec. N. 52° 52′ 4′′. A 4, flushed white; B 14, clear blue.
4. § PERSEI—A BRIGHT STAR with a companion in the hero's hip; R. A., 3h. 31m. 33s.; Dec., N. 47° 16' 2". About 3° south-west of a Persei. A 8%, white; B 11, pale blue.
5. & PERSEI-A NEAT DOUBLE STAR in the right knee; R. A. 3h. 47m. 08s.; Dec. N. 39° 32′ 4′′. A 31⁄2, pale white; B 9, lilac; a fine delicate object.
6. PERSEI-A DELICATE QUADRUPLE STAR; R. A. 3h. 44m. 05s.; Dec. N. 81° 24′ 2′′. A 3, flushed white; B 10, smalt blue; C 12, ash-colored; D 11, blue. It is situated in the right foot, and is designated by Smyth as "an elegant group."
7.7 PERSEI-A FINE DOUBLE STAR in the head of the figure; R. A. 2h. 39m. 04s.; Dec. N. 55° 13′ 5′′. A 5, orange; B 8%, smalt blue; the colors in fine contrast.
8. A GORGEOUS CLUSTER in the sword handle of Perseus; R. A. 2h. 08m. 58s.; Dec. N. 56° 24' 4". It may be seen with the naked eye, and when seen through a good telescope, is one of the most magnificent objects in the heavens. Map VIII., Fig. 25.
9. AN EXTENSIVE AND RICH CLUSTER on the right side of Perseus, in a rich portion of the galaxy. R. A. 3h. 04m. 01s.; Dec. N. 46° 37' 9". Smyth says "it has a gathering spot about 4' in diameter, where the star-dust glows among minute points of light." Herschel says, "the large stars are arranged in lines like interwoven letters.
10. An ELONGATED NEBULA; R. A. 2h. 30m. 25s.; Deo. N. 38° 21′ 8′′; supposed to be a vast ring, seen obliquely. Map VIII., Fig. 26.
11. A pretty compressed OVAL group of stars, in the left knee of Perseus, nearly midway between 2 and μ; R. A. 8h. 58m. 11s.; Dec. N. 49° 04' 05". A well-marked object, surrounded by a curve of larger stars, somewhat in the form of the letter D. Map VIII., Fig. 27.
TELESCOPIC OBJECTS.-Alpha? Beta? Gamma? Clusters? Nebula? Which shown on the map?
Delta? Epsilon? Zeta? Eta?
CONSTELLATIONS ON THE MERIDIAN IN JANUARY.
TAURUS (THE BULL).-MAP III.
62. TAURUS is represented in an attitude of rage, as if about to plunge at Orion, who seems to invite the onset by provoca tions of assault and defiance. Only the head and shoulders of the animal are to be seen; but these are so distinctly marked that they cannot be mistaken.
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.
63. 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.
64. Taurus 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 names of the Pleiades are Alcione, Merope, 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 informs us that, with a twelve feet telescope, he saw 78 stars; and Rheita affirms that he counted 200 stars in this small cluster. For its appearance through an ordinary telescope, see Map VIII., Fig. 28.
The most ancient authors, such as Homer, Attalus, and Geminus, counted only sic Pleiades; but Simonides, Varro, Pliny, Aratus, Hipparchus, and Ptolemy, reckon them
62. How is Taurus represented? How much of him seen? What constellations most brilliant? 68. In what sign is Taurus? What constellation? How 4000 years ago? What next led the year? What now? At what time does Taurus set with the sun? How situated? 64. How many visible stars in Taurus? Clusters? How situated? Names of the Pleiades? What said of Merope? How many of the Pleiades visible to the naked eye? Dr. Hook and Rheita? Ancient authors?
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 difference in distinguishing them with the naked eye.
65. The Pleiades are so called from the Greek word, nåɛɛɩv pleein, to sail; because at this season of the year, they were considered "the star of the ocean" to the benighted mariner.
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,
Then sailors quarter'd heaven, and found a name
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 cœlo,
Arcturum, pluviasque Hyadas, geminosque Triones,
"Observe the stars, and notes their sliding course,
And bright Orion, arm'd with burnished 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,
66. 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 Savior, the heliacal rising of the Pleiades took place on the 11th of May, about the time of harvest "When, Atlas-born, the Pleiad stars arise
Before the sun above the dawning skies,
'Tis time to reap; and when they sink below
Thus, in all ages, have the stars been observed by the husbandman, for "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 precession (50%), will give 2465 years since the time of Thales. Thus does astronomy become the parent of chronology.
65. Why Pleiades so called? Remark, and quotations from Virgil? 66. What said of Alcyone? Of the other five? When on the meridian? Serve what purpose? Period, and remark of Hesiod? Of Pliny? What calculation respecting the passage of the Pleiade over the meridian ?
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 seven stars culminate on the 5th of 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.
67. The Pleiades are also sometimes called Vergilia, or the "Virgins of Spring ;" because the sun enters this cluster in the
season of blossoms," about the 18th or 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 Succoth-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 stars.
68. 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. (Map VIII., Fig. 29.) 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
The ancient Greeks counted seven in this cluster:
"The Bull's head shines with seven refulgent flames,
69. Aldebaran is of Arabic origin, and takes its name from two words which signify, He went before, or led the way"— alluding 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 48 minutes after Alcyone, on the 1st. When Aries is about 27° high, Aldebaran is just rising to the east. So MANILIUS :—
"Thus, when the Ram hath doubled ten degrees,
A line 15% 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 8°, 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, 8° apart, with the brightest on the north. That very bright star 17° N. of Beta, is Capella, in the constellation Auriga.
67. What other name have the Pleiades, and why? Citation from Job? Syrian name? 68. Where are the Hyades situated? How known? Where the most brilliant star? Name? Are they shown on the map? 69. Origin and import of the name Aldebaran? When does it come to the meridian at 9 o'clock p.m. ? Where is Beta? In what other constellation? Zeta, and its distance? How situated with reference to Aldebaran and Beta? How Beta and Zeta? Capella?