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TELESCOPIC OBJECTS.

1. A neat DOUBLE STAR in the space between the Polish Bull, and the Eagle's wing, 8° east of a Ophiuchi, in a line towards Altair; R. A. 17h. 58m. 17s.; Dec. N. 11° 59′ 08′′. A 8, straw-color; B 8, sapphire blue.

2. A fine PLANETARY NEBULA, in a rich vicinity, in the shoulder; R. A. 18h. 04m. 21s.; Dec. N. 6° 49' 02". A small but bright object, regarded by Prof. Struve as one of the most curious in the heavens. Many telescopic stars in the field.

SCUTUM SOBIESKI (SOBIESKI'S SHIELD).—MAP V.

216. This small figure is between the head of the Polish Bull, and the head of Sagittarius. Its four principal stars are of the 5th magnitude; and it is important chiefly for its Telescopic Objects.

TELESCOPIC OBJECTS.

1. A DOUBLE STAR 1° northeast of μ Sagittarii; R. A. 18h. 07m. 87s.; Dec. S. 19° 55' 05". A 8, and B 10, both grey.

2. A neat DOUBLE STAR, in a long and straggling assemblage below the Shield; R. A. 18h. 10m. 36s.; Dec. S. 17° 11' 07". A 9, and B 11. both bluish. It is 4° from μ Sagittarii, in a very rich vicinity; several splendid fields lying only about 1° south of it.

3. A BEAUTIFUL CLUSTER below the base of the Shield; R. A. 18h. 08m. 49s.; Dec. S. 18° 27'05". A line from a Aquile, southwest over 2 Antinoi, and continued as far again, will reach this object.

4. A SCATTERED BUT LARGE CLUSTER, north-half-east from u Sagittarii 7°; R. A. 18h. 09m. 448.; Dec. S. 13° 50′ 05". Stars disposed in pairs, the whole forming a very pretty object in a telescope of tolerable capacity.

5. A HORSE-SHOE NEBULA just below the Shield; R. A. 18h. 11m. 23s.; Dec. S. 16° 15′ 08′′. It has been compared to a Greek . Map IX., Fig. 59. Five stars in the object, and others in the field, and the region around it particularly rich. Sir William Herschel computed that there were 285,000 stars in a space 10° long, and 2' wide; many of which were 2,800 times as far off as Sirius !

SAGITTARIUS (THE ARCHER).—MAP V.

217. This is the ninth sign and the tenth constellation of the Zodiac. It is situated next east of Scorpio, with a mean declination of 35° S., or 12° below the ecliptic. The sun enters this sign on the 22d of November, but does not reach the constellation before the 7th of December. It occupies a considerable space in the southern hemisphere, and contains a number of subordinate, though very conspicuous stars. The whole number of its visible stars is sixty-nine, including five of the 3d magnitude, and ten of the 4th.

TELESCOPIC OBJECTS.-What double star? What nebula ? 216. Situation and components of Scotum Sobieski? For what chiefly important? TELESCOPIC OBJECTS.-What double stars? Clusters? Nebula? 217. Order of Sagittarius, in the signs and constellations? When does the sun enter this sign? The constellation? Its extent? Number and size of its stars?

218. Sagittarius may be readily distinguished by means of five stars of the 3d and 4th magnitudes, forming a figure resembling a little, short, straight-handled dipper, turned nearly bottom upward, with the handle to the west, familiarly called the Milk-Dipper, because it is partly in the Milky-Way.

This little figure is so conspicuous that it cannot easily be mistaken. It is situated about 33° E. of Antares, and comes to the meridian a few minutes after Lyra, on the 17th of August. Of the four stars forming the bowl of the Dipper, the two upper ones are only 3° apart, and the lower ones 5°.

The two smaller stars forming the handle, and extending westerly about 4°, and the easternmost one in the bowl of the Dipper, are all of the 4th magnitude. The star in the end of the handle, is marked Lambda, and is placed in the bow of Sagittarius, just within the Milky-Way. Lambda may otherwise be known by its being nearly in a line with two other stars about 4° apart, extending toward the S. E. It is also equidistant from Phi and Delta, with which it makes a handsome triangle, with the vertex in Lambda. About 5° above Lambda, and a little to the west, are two stars close together in the end of the bow, the brightest of which is of the 4th magnitude, and marked Mu. This star serves to point out the winter solstice, being about 2° N. of the tropic of Capricorn, and less than one degree east of the solstitial colure.

If a line be drawn from Sigma through Phi, and produced about 6° farther to the west, it will point out Delta, and produced about 3° from Delta, it will point out Gamma; stars of the 3d magnitude, in the arrow. The latter is in the point of the arrow, and may be known by means of a small star just above it, on the right. This star is so nearly on the same meridian with Etanin, in the head of Draco, that it culminates only two minutes after it.

A few other conspicuous stars in this constellation, forming a variety of geometrical figures, may be easily traced from the map.

HISTORY.

This constellation, it is said, commemorates the famous Centaur Chiron, son of Philyra and Saturn, who changed himself into a horse, to elude the jealous inquiries of his wife Rhea.

Chiron was famous for his knowledge of music, medicine and shooting. He taught mankind the use of plants and medicinal herbs; and instructed, in all the polite arts, the greatest héroes of the age. He taught Esculapius physic, Apollo music, and Hercules astronomy; and was tutor to Achilles, Jason, and Æneas. According to Ovid, he was slain by Hercules, at the river Evenus, for offering indignity to his newly married bride.

"Thou monster double shap'd, my right set free-
Swift as his words, the fatal arrow flew;

The Centaur's back admits the feather'd wood,
And through his breast the barbed weapon stood;
Which, when in anguish, through the flesh he tore,
From both the wounds gush'd forth the spumy gore."

The arrow which Hercules thus sped at the Centaur, having been dipped in the blood of the Lernæan Hydra, rendered the wound incurable, even by the father of medicine himself, and he begged Jupiter to deprive him of immortality, if thus he might escape his excruciating pains. Jupiter granted his request, and translated him to a place among the constellations.

"Midst golden stars he stands refulgent now,

And thrusts the Scorpion with his bended bow."

This is the Grecian account of Sagittarius; but as this constellation appears on the ancient zodiacs of Egypt, Dendera, Esne, and India, it seems conclusive that the Greeks

218. How distinguished? Where is Lambda? How known? Where are Mu, Delta, and Gamma?

HISTORY.-What does Sagittarius commemorate? Story of Chiron? What said of the antiquity of this constellation?

only borrowed the figure, while they invented the fable. This is known to be true with respect to very many of the ancient constellations. Hence the jargon of the conflicting accounts which have descended to us.

TELESCOPIC OBJECTS.

1. SAGITTARII-A MULTIPLE STAR in the north end of the Archer's bow; R. A. 18h. 04m. 11s.; Dec. S. 21° 05′ 07′′ About 25° east-northeast of Antares. A 8%, pale yellow; B 16, blue; C 9%, and D 10, both reddish.

2. σ SAGITTARII-A star with a distant companion in the Archer's right shoulder; R. A. 18h. 45m. 20s.; Dec. S. 26° 29′ 03′′. A 3, ruddy; B 91⁄2, ash-colored.

3. A very delicate TRIPLE STAR, between the heads of Sagittarius and Capricorn, about 25 south-by-west of Altair, and 10° west of B Capricorni; R. A. 19h. 81m. 33s.; Dec. S. 16° 39' 02". A 5%, yellow; B 8, violet; C 16, blue. Other small stars in the field.

4. A LARGE AND COARSE CLUSTER of minute stars, close to the upper end of the bow, and In the Galaxy; R. A. 18h. 03m. 08s.; Dec. S. 21° 36′ 01′′. Stars of the 10th to 18th magnitudes. A rich field of no particular form.

5. A LOOSE CLUSTER in the Galaxy, between the Archer's head and Sobieski's Shield; R. A. 18h. 22m. 14s.; Dec. S. 19° 10' 02". The most prominent are a pair of 8th magnitude stars. It is about 5° northeast of u Sagittarii.

6. A FINE GLOBULAR CLUSTER between the head and bow, near the solsticial colure; R. A. 18h. 26m. 25s.; Dec. S. 24° 01' 04". A fine group, compressed towards the center, with several single stars in the field. Map IX., Fig. 60.

CORONA AUSTRALIS (THE SOUTHERN CROWN).—MAP V.

219. This is a small and unimportant constellation near the fore-legs of Sagittarius; and between them and the Milky-Way. R. A. about 18h. 44m.; Dec. S. 40°. Its four principal stars are of the 5th magnitude, situated near each other, and arranged in a gentle curve line, lying north and south. It has no Mythological History, or Telescopic Objects worthy of notice.

AQUILA ET ANTINOUS (THE EAGLE AND ANTINOUS).-MAP V.

220. This double constellation is situated directly south of the Fox and Goose, and between Taurus Poniatowskii on the west, and the Dolphin on the east. It contains seventy-one stars, including one of the 1st magnitude, nine of the 3d, and seven of the 4th. It may be readily distinguished by the position and superior brilliancy of its principal star.

221. Altair, the principal star in the Eagle, is of the 1st, or between the 1st and 2d magnitudes. It is situated about 14°

TELESCOPIC OBJECTS.-Mu? shown on the map? Point it out. 219. Describe Corona Australis. Its principal stars? History and Telescopic Objects? 220. Situation of Aquila and Antinous ? Number and size of its principal stars? 221. Altair-how known? Stars each side of it? Use of Altair in navigation?

Sigma ? What triple star? What clusters? Which

What

S. W. of the Dolphin. It may be known by its being the largest and middle one of the three bright stars which are arranged in a line bearing N. W. and S. E. The stars on each side of Altair are of the 3d magnitude, and distant from it about This row of stars very much resembles that in the Guards of the Lesser Bear.

2°.

Altair is one of the stars from which the moon's distance is taken for computing longitude at sea. Its mean declination is nearly 84° N., and when on the meridian, it occupies nearly the same place in the heavens that the sun does at noon on the 12th day of April. It culminates about 6 minutes before 9 o'clock, on the last day of August. It rises acronically about the beginning of June.

Ovid alludes to the rising of this constellation; or, more probably, to that of the principal star, Altair :

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The northernmost star in the line, next above Altair, is called Tarazed. In the wing of the Eagle, there is another row composed of three stars, situated 4° or 5° apart, extending down toward the southwest; the middle one in this line is the smallest, being only of the fourth magnitude; the next is of the 8d magnitude, marked Delta, and situated 8° S. W. of Altair.

As you proceed from Delta, there is another line of three stars of the 3d magnitude, between 5 and 6° apart, extending southerly, but curving a little to the west, which mark the youth Antinous. The northern wing of the Eagle is not distinguished by any conspicuous stars.

Zeta and Epsilon, of the 3d magnitude, situated in the tail of the Eagle, are about 2° apart, and 12° N. W. of Altair. The last one in the tail, marked Epsilon, is on the same meridian, and culminates the same moment with Gamma, in the Harp.

From Epsilon, in the tail of the Eagle, to Theta, in the wrist of Antinous, may be traced a long line of stars, chiefly of the 3d magnitude, whose letter names are Theta, Eta, Mu, Zeta and Epsilon. The direction of this line is from S. E. to N. W., and its length is about 25°.

Eta is remarkable for its changeable appearance. Its greatest brightness continues but 40 hours; it then gradually diminishes for 66 hours, when its luster remains stationary for 30 hours. It then waxes brighter and brighter, until it appears again as a star of the 3d magnitude.

From these phenomena, it is inferred that it not only has spots on its surface, like our sun, but that it also turns on its axis.

Similar phenomena are observable in Algol, Beta, in the Hare, Delta, in Cepheus, and Omicron, in the Whale, and many others.

"Aquila the next,

Divides the ether with her ardent wing:
Beneath the Swan nor far from Pegasus,
POETIC EAGLE."

poetic quotation? Where are Tarazed and Delta? Zeta and Epsilon? Theta? Eta ? For what remarkable ?

HISTORY.

Aquila, or the Eagle, is a constellation usually joined with Antinous. Aquila is sup. posed to have been Merops, a king of the island of Cos, in the Archipelago, and the husband of Clymene, the mother of Phæton; this monarch having been transformed into an eagle, and placed among the constellations. Some have imagined that Aquila was the eagle whose form Jupiter assumed when he carried away Ganymede; others, that it represents the eagle which brought nectar to Jupiter while he lay concealed in the cave at Crete, to avoid the fury of his father, Saturn. Some of the ancient poets say, that this is the eagle which furnished Jupiter with weapons in his war with the giants:

"The towering Eagle next doth boldly soar,

As if the thunder in his claws he bore;
He's worthy Jove, since he, a bird, supplies

The heaven with sacred bolts, and arms the skies."

Manilius.

The eagle is justly styled the "sovereign of birds," since he is the largest, strongest, and swiftest of all the feathered tribe that live by prey. Homer calls the eagle, "the strong sovereign of the plumy race;" Horace styles him

"The royal bird, to whom the king of heaven

The empire of the feathered race has given :"

And Milton denominates the eagle the "Bird of Jove." Its sight is quick, strong and piercing, to a proverb: Job xxix., 28, &c.

"Though strong the hawk, though practised well to fly,

An eagle drops her in the lower sky;

An eagle when deserting human sight.

She seeks the sun in her unwearied flight;

Did thy command her yellow pinion lift

So high in air, and set her on the clift

Where far above thy world she dwells alone,

And proudly makes the strength of rocks her own;
Thence wide o'er nature takes her dread survey,

And with a glance predestinates her prey?

She feasts her young with blood; and hovering o'er
The unslaughtered host, enjoys the promised gore."

ANTINOUS.

Antinous is a part of the constellation Aquili, and was invented by Tycho Brahe Antinous was a youth of Bithynia, in Asia Minor. So greatly was his death lamented by the emperor Adrian, that he erected a temple to his memory, and built in honor of him a splendid city, on the banks of the Nile, the ruins of which are still visited by travelers with much interest.

TELESCOPIC OBJECTS.

1. a AQUILE (Altair)-A bright star in the neck, with a distant companion; R. A. 19h. 42m. 58s.; Dec. N. 8° 26' 09". A 1%, pale yellow; B 10, violet tint.

2. B AQUILE (Alshain)—A DOUBLE STAR, also in the neck of Aquila, and the head of Antinous; R. À. 19h. 47m. 26s.; Dec. N. 6° 00′ 07′′. About 2 south-southeast of Altair. A 8%, pale orange; B 10, pale grey; with other stars in the field.

8. Y AQUILE (Tarased)-A star in the back of Aquila, on a line with a and B, with a minute companion; R. Á. 19h. 38m. 88s.; Dec. N. 10° 18′ 06′′. A 3, pale orange; B 12, dusky; other stars around.

4. 8 AQUILE, in the southern wing; R. A. 19h. 17m. 25s.; Dec. N. 2° 48' 00". Has a distant companion. A 8%, white; B 12, livid; other stars in the field.

5. AQUILE, in the tail; R. A. 18h. 58m. 02s.; Dec. N. 13° 37′ 08'. A 3, greenish tint; B 11, livid; two other stars in the field.

6. A neat DOUBLE STAR on the margin of the lower wing; R. A. 18h. 57m. 59s.; Dec. N. 6° 18′ 08′′. A 7%, lucid white; B 9, cerulean blue. A fine object, not difficult to find, as

HISTORY.-Different suppositions respecting? Manilius? Horace? Milton? What said of Antinous?

TELESCOPIC OBJECTS.-Alpha? Beta Gamma? Delta? Xi? Other double stars? What clusters? Which shown on the map? What nebula?

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