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produced south westerly, 8° farther, it will reach to (d) Delta, a star of the 3d magnitude in the left breast. This star may be otherwise known by its forming a line, N. and S., with two smaller ones on either side of it; or, by its constituting, with two others, a very small triangle, S. of it.

Nearly in a line with Almaack, Merach and Delta, but curv ing a little to the N. 7° farther, is a lone star of the 2d magnitude, in the head, called Alpheratz (a). This is the N.E. 201 ner of the great "Square of Pegasus," to be hereafter described

It will be well to have the positie.pheratz well fixed in the mind, because it is but one minute west of the great equinoctial colure, or first meridian of the heavens, and forms nearly a right line with Algenib, in the wing of Pegasus, 14' S. of it, and with Beta in Cassiopeia, 30° N. of it. If a line, connecting these three stars, be produced, it will terminate in the pole. These three guides, in connection with the North Polar Star, oint out to astronomers the position of that great circle in the heavens from which the right ascension of all the heavenly bodies is measured.

MYTHOLOGICAL HISTORY.

32. The story of Andromeda, from which this constellation derives its name, is as follows: She was daughter of Cepheus, King of Ethiopia, by Cassiopeia. She was promised in marriage to Phineus, her uncle, when Neptune drowned the kingdom, and sent a sea monster to ravage the country, to appease the resentment which his favorite nymphs bore against Cassiopeia, because she had boasted herself fairer than Juno and the Nereides. The oracle of Jupiter Ammon was consulted, and nothing could pacify the anger of Neptune unless the beautiful Andromeda should be exposed to the sea monster. She was accordingly chained to a rock for this purpose, near Joppa (now Jaffa, in Syria), and at the moment the monster was going to devour her, Perseus, who was then returning through the air from the conquest of the Gorgons, saw her, and was captivated by her beauty.

"Chained to a rock she stood; young Perseus stay'd
His rapid flight, to woo the beauteous maid."

He promised to deliver her and destroy the monster if Cepheus would give her to him in marriage. Cepheus consented, and Perseus instantly changed the sea monster into a rock, by showing him Medusa's head, which was still reeking in his hand. The enraged Phineus opposed their nuptials, and a violent battle ensued, in which he, also, was turned into a stone, by the petrifying influence of the Gorgen's head.

The morals, maxims, and historical events of the ancients, were usually communicated in fable or allegory. The fable of Andromeda and the sea monster might mean that she was courted by some monster of a sea-captain, who attempted to carry her away, but was prevented by another more gallant and successful rival.

TELESCOPIC OBJECTS.

33. Under the head of Telescopic Objects, will be included clusters and nebule that are visible to the naked eye, as well as the principal objects of interest that are strictly telescopic. In describing the location of these objects, R. A. will denote Right Ascen sion; and Dec., Declination. The initials N. and S. will indicate whether the declination is North or South of the equinoctial.

In describing the location of the telescopic object, the R. A. will be given in time, viz., in hours, minutes, and seconds, instead of degrees, minutes, and seconde; cach hour answering to 15°. The hour circles are listinctly drawn on all the maps, the first being 15 east of the equinoctial colure (Map (.), and so on eastward to the same pent again. The hours will be seen marked just under the equinoctial, which is marked into degrees, each of which answers to four minutes of time. The student will soon LC it much more convenient to reckon R. A. by hours, on the maps, than by degrees, &c.

32. HISTORY.-What may it have meant?

83. What included among Telescopic Objects? What meant by R. A.? Dec.? N. and 8.? How R. A. laid down? How on map? What mode of describing components of Jonble stars? Of a Andromeda ? Of discrepancies between R. A. given, and loca tion of stars on the ps? How is R. A. given in locating objects? Why? Hoy are hours marked on the maps? The minutes?

84. In consequence of the perpetual recession of the equinoxes westward, the R. A of objects is constantly increased by about 50" per year. It is vain, therefore, to attempt to give R. A. for the time when a book will be used; or to construct maps that wil! slow objects in their true place, for different years to come. The necessary allowance Just be made in all cases; so that the R. A. for one epoch is about as good as another. The R. A. here given is from Smyth's Celestial Cycle, epoch Jan. 1, 1840. Maps should be re-engraved every fifty years, but for all shorter periods allowance can be made by the student. As the maps accompanying this work were drawn and engraved in 183, their present R. A. (1854) is about 17' or 4m. of time east of their places on the maps. 35 The order in which the telescopic objects will be arranged is first the double stars; secondly, clusters; and lastly the nebula. The double stars will be classed according to their order in the respective constellations; i.e., a first, B next, &c. Thus, as the argest objects are first named, the student can begin with those easiest found, and Jequiring the least telescopic power; and proceed from the easier to those more diffi sult. The same plan is generally pursued with the clusters and nebulæ.

TELESCOPIC OBJECTS IN ANDROMEDA.

1. a ANDROMEDE (Alpheratz)-A star with a minute companion, R. A. Oh. Om. OSs.. Dec., N. 26' 12' 05". A. 1, bright white; B. 11, purplish. On the map it is west of the equinoctial, the map having been engraved some twenty years; but the equinox having constantly receded westward, had passed Alpheratz before 1840, some 8'. Similar discrepancies between the R. A. given and the location of different stars on the map, are due to the same cause.

2. ANDROMEDA (Merach)—A bright star with a distant telescopic companion, R. A. Ih. 00m. 47s.; Dec., N. 84° 46' 08". A. 2, fine yellow; B. 12, pale blue, with several small stars in the field.

3. Y ANDROMEDE (Almaack)—A splendid doublE STAR on the right foot, R. A. 1h. 54m. Jos; Dec. N. 41° 33' 06". A. 3%, orange color; B. 5, emerald green. Found by a line from to B, and about twice as far beyond. (Map VIII., Fig. 1.)

4. ANDROMEDE-A bright star on the right breast, with a distant telescopic companion, R. A. Oh. 30m. 47s.; Dec., N. 29° 59′ 01. A. 8, crange; B. 11, dusky; with the small stars in the southern part of the field.

5. K ANDROMEDE-A wide, but delicate TRIPLE STAR, in the northern hand; midway between Pegasi and a Cassiopeia; or about 18° from each; R. A. 23h. 32m. 33s; Dec., N 43° 27' 0". A. 5, brilliant white; B. 14, dusky; C. 12, ash-colored.

C. AN ELONGATED NEBULA on the lady's right foot, R. A, 2h. 12m. 35s.; Dec., N. 41° 86". It was discovered by Miss Caroline Herschell, in 1783. Sir William Herschell described it as having "a black division or chink in the middle." He regarded it as a flat ring of enormous dimensions, seen very obliquely. Captain Smyth says: "In my telescope it is certainly brighter at the edges than along the central part." See map VIII., Fig. 21. 7. About 2° from Nu at the north-western extremity of the girdle, R. A. 00° 84m. 05s., N. Dec., 40° 23' 06", is a remarkable nebula of very minute stars, and the only one of the kind which is ever visible to the naked eye. It resembles two cones of light, joined at their base, about 3° in length, and 4° in breadth. It was known as far back as A.D. 905, is of an oval shape, and is described by Smyth as "an overpowering nebula, with a companion about 25' in the south vertical." Sir William Herschell considered this the nearest of all the great nebulæ, and yet so remote that it would require 6,000 years for light to pass from it to our system, though flying at the rate of 190,000 miles per second! Fig. 22, map VIII., is a representation of this object.

PISCES (THE FISHES).-MAP V.

36. This constellation is now the first in order of the twelve constellations of the Zodiac, and is usually represented by two fishes tied a considerable distance apart, at the extremities of a long undulating cord, or ribbon. It occupies a large triangular space

84. What said of the change of R. A of objects? Cause? Epoch of R. A. given in book? Of that marked on maps? Allowance to be made in finding objects by maps 15. Order in which objects are presented? Advantage of this arrangement?

1'ELESCOPIC OBJECTS.-What double stars? a? B? y? What clusters cr nebuia Shown on map, or not?

2% Pisces? Where situated? What now called?

in the heavens, and its outline at first is somewhat difficult to be traced.

In consequence of the annual precession of the stars, the constellation Pisces has now come to occupy the sign Aries; each constellation having advanced one whole sign it. the order of the Zodiac. The Sun enters the sign Pisces, while the Earth enters that of Virgo, about the 19th of February, but he does not reach the constellation Pisces before the 6th of March. The Fishes, therefore, are now called the "Leaders of the Celestial Hosts."-See Aries.

37. That loose assemblage of small stars directly south of Merach, in the constellation of Andromeda, constitutes the Northern Fish, whose mean length is about 16°, and breadth, Its mean right ascension is 15°, and its declination 25° N. Consequently, it is on the meridian the 24th of November; and from its breadth, is more than a week in passing over it.

7°.

38. The Northern Fish and its ribbon, beginning at Merach. may by a train of small stars, be traced in a S. S. easterly direc tion, for a distance of 33°, until we come to the star El Rischa, of the 3d magnitude, which is situated in the node, or flexure of the ribbon. This is the principal star in the constellation, and is situated 2° N. of the equinoctial, and 53 minutes east of the meridian.

Seven degrees S. E. of El Rischa, passing by three or four very small stars, we come to Mira, in the whale, a star of about the 8d magnitude, and known as the "Wonderful Star of 1596." El Rischa may be otherwise identified by means of a remarkable cluster of five stars in the form of a pentagon, about 15° E. of it.-See Cetus.

39. From El Rischa the ribbon or cord makes a sudden flexure, doubling back across the ecliptic, where we meet with three stars of the fourth magnitude situated in a row 3 and 4° apart, marked on the map Zeta, Epsilon, Delta. From Delta the ribbon runs north and westerly along the Zodiac, and terminates at Beta, a star of the 4th magnitude, 11° S. of Markab in Pegasus.

This part of the ribbon, including the Western Fish at the end of it, has a mean declination of 5° N., and may be seen throughout the month of November, passing the meridian slowly to the W., near where the sun passes it on the 1st of April.

40. Twelve degrees W. of this Fish, there are four small stars situated in the form of the letter Y. The two Fishes, and the cord between them, make two sides of a large triangle, 30° and 40° in length, the open part of which is towards the N. W When the Northern Fish is on the meridian, the Western is early two hours past it. This constellation is bounded N. by

87. Northern Fish? Length? Dec.? When on the meridian? 89. How trace the Northern Fish? To what star? Magnitude? Were situated? 89. From El Rischa From Delta? Mean declination of this part of the ribbon? 40. What 12 west of this fish? at do the two fishes, &c., make. Boundaries of Pisces?

Andromeda, W. by Andromeda and Pegasus, S. by the Cascade and E. by the Whale, the Ram and the Triangles.

When, to enable the pupil to find any star, its direction from another is given, the latter is always understood to be on the meridian.

After a little experience with the maps, even though unaccompanied by directions the ingenious youth will be able, of himself, to devise a great many expedients and facili Lies for tracing the constellations, or selecting out particular stars.

In using a circumpolar map, face the pole, and hold it up in your harde in such a Banner that the part which contains the name of the given month shall be uppermos*, and you will have a portraiture of the heavens as seen at that time.

The constellations about the Antarctic Pole are not visible in the United States; those about the Arctic or Northern Pole, are always visible.

HISTORY.

41. The ancient Greeks, who have some fable to account for the origin of almoa every constellation, say, that as Venus and her son Cupid were one day on the banks of the Euphrates, they were greatly alarmed at the appearance of a terrible giant, named Typhon. Throwing themselves into the river, they were changed into fishes, and by this means escaped danger. To commemorate this event, Minerva placed two fishes among the stars.

According to Ovid, Homer, and Virgil, this Typhon was a famous giant. He had a hundred heads, like those of a serpent or dragon. Flames of devouring fire darted from his mouth and eyes. He was no sooner born, than he made war against heaven, and so frightened the gods, that they fled and assumed different shapes. Jupiter became a am: Mercury, an Ibis; Apollo, a crow; Juno, a cow; Bacchus, a goat; Piana, a cat; enus, a fish, &c. The father of the gods, at last, put Typhon to flight, and crushed him ader Mount Etna.

The sentiment implied in the fable of this hideous monster, is evidently this: that Are is in the world a description of men whose mouth is so full of cursing and bitter. ness," derison and violence, that modest virtue is sometimes forced to disguise itself, or flee from their presence.

In the Hebrew Zodiac, Pisces is allotted to the escutcheon of Simeon.

No sign appears to have been considered of more malignant influence than Pisces. The astrological calendar describes the emblems of this constellation as indicative of violence and death Both the Syrians and Egyptians abstained from eating fish, out of dread and abhorrence; and when the latter would represent anything as odious, or express hatred by hieroglyphics, they painted a fish.

TELESCOPIC OBJECTS.

1. a PISCIUM (El Rischa)—A close double star in the eastern extremity of the ribbon, R. A. Ih. 53m. 46s.; Dec. N. 1° 59′ 03′′. A. 5, pale green; B. 6, blue; a splendid object, and easily found.

2. PISCIUM-A neat double star in the ribbon, about 18° north-west of a, R. A. 1h. 5m. 218.; Dec. N. 6° 43′ 07′′. A. 6, silvery white; B. 8, pale gray; a fine object.

8. PISCIUM-A close double star in the space between the two fishes, about half-way between η Andromeda and Ceti; R. A. 1h. 2m. 81s.; Dec. N. 8' 42. A. 8, white; B. 14, pale blue.

4. A neat DOUBLE STAR, about 4° south of Algenib, in the wing of Pegasus, R. A. O 1m. 53s.; Dec. N. 10° 14' 06". A. 6, silvery white; B. 18, pale blue.

5. A FAINT NEBULA in the eye of the western Fish, about 10' south-half-east of Mar kab, near γ Piscium; R. A. 23h. 06m. 36s.; Dec. 8 89 7" a very difficult object.

CASSIOPEIA.-MAP VI.

42. Cassiopeia is represented on the celestial map in regal state seated on a throne or chair, holding in her left hand the branch

41. HISTORY ?-Greek account? Ovil's and others? Sentiment or moral? Hebre7 Zodiac? Astrology?

Tr800PIU OBJECTS.-Double stars 42. Cassiopeia? How represented

Clusters?
Head?

Nebulæ ?

Shown on map, or notf

ɔf a palm tree. Her head and body are seen in the Milky Way Har foot rests upon the Arete Circle, upon which her chair is placed She is surrounded by the chief perse ages of her roya family. The king, her husbal, is on her right hand-Perseus, her se in-law, on her left-and Andromeda, her daughter, just

ove her.

13. This constellation is situated 26° N. of Andromeda, and nidway between it and the North Polar Star. It may be seen from our latitude, at all hours of the night, and may be traced out it almost any season of the year. Its mean d clination is 609 N. and its right ascension 12. It is on our meridian the 226 of November, but does not sensibly change its position for several days; for it should be remembered that the apparen motion of the stars becomes slower and slower, as they approxi te the poles.

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

"Wide ner stars

Dispersed, nor shine with mutual aid improved;
Nor dazle, brillant with contigous flame:
Their number "ty-five."

45. Caph, in the garland of the chair, is almost exactly in the equine iial colure, 30 N.of Alpheratz, with which, and the Polar Star, it forms a straight line. 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. Sheair, in the breast, is the uppermost star of the five bricht ones, and is 5'S E. of Caph, the other three bright exes, forming the air, are easily distinguished, as they meet the eye at the first glance.

There is an importance attached to the pocision of Caph that concerns the mariner and the surveyor. It is used, in connection with observations on the Polar Star, for de ermining the latitude of places, and for discovering the magustle variation of the neelle.

46. It is generally supposed that the North Polar Star, so lied, is the real immovable pole of the havens; but this is a mirtake. It is so near the tree pole that has obtained the

14. Number of 45. Caph? cosa to Capl? 48. Poi

42. Sitnation? How seen? R. A an. De ? Whea on masillan ↑ stars? Magnitude? Figure? Character of this coDNE situated? When on merid'ac? Ehedir? Imperta.or

star? Is it the true pole? What variat on? How pile or welated with reference t

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