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Sabeism, or the worship of the host of heaven. The heresy of the Oputes, mentioned by Mosheim, in his Ecclesiastical History, originated, perhaps, in the admission into the Christian church of some remnant of the ancient and popular sect of Sabeists, who adored the celestial Serpent.

According tc ancient tradition, Ophiuchus is the celebrated physician Esculapius, son of Apollo, who was instructed in the healing art by Chiron the Centaur; and the serpent, which is here placed in his hands, is understood by some to be an emblem of his sagacity and prudence; while others suppose it was designed to denote his skill in heal ing the bite of this reptile. Biblical critics imagine that this constellation is alluded to in the following passage of the book of Job:

66 By his spirit He hath garnished the Heavens; his hand hath formed the crooked serpent." Mr. Green supposes, however, that the inspired writer here refers to Draco because it is a more obvious constellation, being nearer the pole where the constellation. were more universally noticed; and moreover, because it is a more ancient constellation than the Serpent, and the hieroglyphic by which the Egyptians usually represented the heavens.

TELESCOPIC OBJECTS.

1. a SERPENTIS (Unuk)—A star with a minute companion on the heart of the Serpent; R. A. 15h. 36m. 23s.; Dec. N. 6° 55'9′′. A 2%, pale yellow; B 15, fine blue. An extremely delicate object.

2. 3 SERPENTIS-A delicate DOUBLE STAR in the Serpent's under jaw; R. A. 15h. 88m. 48s.; Dec. N. 15° 55′ 7′′. A 8%, and B 10, both pale blue.

3. SERPENTIS-An elegant DOUBLE STAR in the bend of the neck; R. A. 15h. 27m. 108.; Dec. N. 11° 04' 7". A 8, bright white; B 5, bluish white. A fine object, about 5° N. W. of Unak.

4. 7 SERPENTIS-A star with a minute companion in the Serpent's body, nearly midway between n Ophiuchi and a Aquilæ; R. A. 18h. 18m. 02s.; Dec. S. 2° 56′ 0°. A 4, golden yellow; B 18, pale lilac. A delicate and difficult object.

5. V SERPENTIS-A wide DOUBLE STAR in the middle of the Serpent, 4° northeast of ni R. A. 17h. 11m. 49s.; Dec. S. 12° 40′ 7′′ A 4%, pale sea-green; B 9, lilac, with a third star in the field.

6. A delicate DOUBLE STAR R. A. 15h. 11m. 08s.; Dec. N. 2° 22′ 6′′. A 5. pale yellow B 10%, light grey. Look 9 southwest of a Serpentis, 24° southeast of Arcturus.

CORONA BOREALIS (THE NORTHERN OROWN).—MAỶ V.

It

186. This beautiful constellation may be easily known by ineans of its six principal stars, which are so placed as to form a circular figure, very much resembling a wreath or crown. is situated directly north of the Serpent's head, between Bootes on the west, and Hercules on the east.

This asterism was known to the Hebrews by the name of Ataroth, and by this name the stars in Corona Borealis are called, in the East, to this day.

187. Alphacca, of the 2d magnitude, is the brightest and middle star in the diadem, and about 11° E. of Mirac, in Bootes. It is very readily distinguished from the others both on account of its position and superior brilliancy. Alphacca, Arcturus, and Seginus, form nearly an isosceles triangle, the vertex of which is at Arcturus.

TELESCOPIC OBJECTS.-Alpha? Beta? Delta? Eta? Nu? &c.

186. How inay Corona Borealis be known? Where situated? Its Hebrew narej 187. Describe Alphacca? How distinguished? What triangle"

188. This constellation contains twenty-one stars, of which only six or eight are conspicuous; and most of these are not larger thar the 3d magnitude. Its mean declination is 30° north, and its meau right ascension 235°; its center is thereforg

the meridian about the last of June, and the first of July.

"And, near to Helice, effulgent rays

Beam, Ariadne, from thy starry crown:
Twenty and one her stars; but eight alone
Conspicuous; one doubtful, or to claim
The second order, or accept the third."

HISTORY.

This beautiful little cluster of stars is said to be in commemoration of a crown presented by Bacchus to Ariadne, the daughter of Minos, second king of Crete. Theseus, king of Athens (1235 B. C.), was shut up in the celebrated labyrinth of Crete, to be devoured by the ferocious Minotaur which was confined in that place, and which usually fed upon the chosen young men and maidens exacted from the Athenians as a yearly tribute to the tyranny of Minos; but Theseus slew the monster, and being furnished with a clew of thread by Ariadne, who was passionately enamored of him, he extricated himself from the difficult windings of his confinement.

He afterward married the beautiful Ariadne according to promise, and carried her away; but when he arrived at the island of Naxos, he deserted her, notwithstanding he had received from her the most honorable evidence of attachment and endearing tender ness. Ariadne was so disconsolate upon being abandoned by Theseus, that, as some say, she hanged herself; but Plutarch says that she lived many years after, and was espoused to Bacchus, who loved her with much tenderness, and gave her a crown of seven star which, after her death, was placed among the stars.

"Resolves, for this the dear engaging dame
Should shine forever in the rolls of fame;
And bids her crown among the stars be placed,
And with an eternal constellation graced.
The golden circlet mounts; and, as it flies,
Its diamonds twinkle in the distant skies;
There, in their pristine form, the gemmy rays
Between Alcides and the Dragon blaze."

Manilius, in the first book of his Astronomicon, thus speaks of the Crown.

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"Near to Bootes the bright crown is view'd,
And shines with stars of different magnitude:
Or placed in front above the rest displays

A vigorous light, and darts surprising rays.
This shone, since Theseus first his faith betray'd,
The monument of the forsaken maid."

TELESCOPIC OBJECTS.

a CORONE BOREALIS (Alphacca)-A bright star with a distant companion; R. a 15h 27m. 54s.; Dec. N. 27° 15' 2". A 2, brilliant white; B 8, pale violet.

2 Y CORONE BOREALIS-A most difficult BINARY STAR, 2° from Alphacca; R. A. 15h. n01s.; Dec. N. 26° 48' 4"; with a distant companion. A 6, flushed white; B, uncertin; C 10, pale lilac.

8.

CORONA BOREALIS-A fine DOUBLE STAR, 10° north and a little easterly from Alphacca; R. A 15h. 33m. 21s.; Dec. N. 37° 09′ 6′′. A 5, bluish white; B 6, smalt blue A beautiject.

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CORONA BOREALIS-A BINARY STAR, midway between the Northern Crown and the if Bootes; R. A. 15h. 16m. 36s.; Dec. N. 30° 52' 2". A north-northwest ray from ɑ Jrona, through B, and half as far again, will hit it. A 6, white; B 6%, golden yellow.

188. How many stars in this constellation? Their magnitudes? Mean declination and right ascension?

HISTORY.-Story respecting Theseus and Ariadne?

TELESCOPIC OBJECTS.-Alpha? Gamma? Zeta? Eta?

Bir John Herschel considered this the most remarkable binary star known, and the cal ne that had completed a whole revolution since its discovery. Estimated period 189

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URSA MINOR (THE LESSER BEAR).-MAP VI.

189. This constellation, though not remarkable in its appear ce, and containing but few conspicuous stars, is, nevertheless, justly distinguished from all others for the peculiar advantage which its position in the heavens is well known to afford to nau tical astronomy, and especially to navigation and surveying.

The stars in this group being situated near the celestial pole, appear to revolve about it, very slowly, and in circles so small as never to descend below the horizon. Hence Ursa Minor wil be above or below, to the right or left of the pole star, according to the hour; as he makes the entire circuit from east to west every 24 hours.

190. In all ages of the world, this constellation has been more universally observed, and more carefully noticed than any other, o account of the importance which mankind early attached to the position of its principal star. This star, which is so near the true pole of the heavens. has from time immemorial been denominated the NORTH POLAR STAR. By the Greeks it is called Cynosyre; by the Romans, Cynosura, and by other nations, Alruccabah. In most modern treatises it bears the name of Polaris, or Alpha Polaris.

191 Polaris is of the 3d magnitude, or between the 2d and 3d, and situated a little more than a degree and a half from the true pole of the heavens, on that side of it which is toward Cassiopeia and opposite to Ursa Major. Its position is pointed out by the direction of the two Pointers, Merak and Dubhe, which lie in the square of Ursa Major. A line joining Beta Cassiopeia, which lies at the distance of 32° on one side, and Megrez, which lies at the same distance on the other, will pass through the polar star.

Of the Pole Star Capt. Smyth observes: At present it is only 1° 33' from the polar point, and by its northerly precession in declination will gradually approach to within 26' 30' of it. This proximity to the actual pole will occur in A. D. 2095, but will not recur for 12,860 years. The period of the revolution of the celestial equinoctial pole about the pole of the ecliptic, is nearly 26,000 years; the north celestial pole, therefore, will be sbout 13,000 years; hence, nearly 49 from the present polar star.

189. For what is Ursa Minor distinguished? What aid of its situation and change o Jos tion! 190. What said of the notice taken of it? Position of its principal star! its Greek and Latin names, &c.? 191 Describe Polafis? How found? Remar'ts of

Capt. Smyth respecting!

192. So general is the popular notion, that the North Polar Star is the true pole of the world, that even surveyors and navigators, who have acquired considerable dexterity in the use of the compass and the quadrant, are not aware that it ever had any deviation, and consequently never make allowance for any. All calculations derived from the observed position of this star, which are founded upon the idea that its bearing is always due north of any place, are necessarily erroneous, since it is in this position only twice in twenty-four hours; once when above, and once when below the pole.

193. Hence, it is evident that the surveyor who regulates his compass by the North Polar Star, must take his observation when the star is on the meridian, either above or below the pole, or make allowance for its altered position in every other situation. For the same reason must the navigator, who applies his quadrant to this star for the purpose of determining the latitude he is in, make a similar allowance, according as its altitude is greater or less than the true pole of the heavens; for we have seen that it is alternately half the time above and half the time below the pole.

194. The method of finding the latitude of a place from the altitude of the polar star, as it is very simple, is very often resorted to. Indeed, in northern latitudes, the situation of this star is more favorable for this purpose than that of any other of the heavenly bodies, because a single observation, taken at any hour of the night with a good instrument, will give the true latitude, without any calculation or correction, except that of its polar aberration.

If the polar star always occupied that point in the heavens which is directly of site the north pole of the earth, it would be easy to understand how latitude could be determined from it in the northern hemisphere; for in this case, to a person on the equator, the poles of the world would be seen in the horizon. Consequently, the star would appear just visible in the northern horizon, without any elevation. Should the person now travel one degree toward the north, he would see one degree below the star, and ho would think it had risen one degree.

And since we always see the whole of the upper hemisphere at one view, when there is nothing in the horizon to obstruct our vision, it follows that if we should travel 10° north of the equator, we should see just 10° below the pole, which would then appear to have risen 10°; and should we stop in the 42d degree of north latitude we should, in like mat ner, have our horizon just 42° below the pole, or the pole would appear to have an clevation of 42°. Whence we derive this general truth: The elevation of the pole of the equator is always equal to the latitude of the place of observation.

Any instrument, then, which will give us the altitude of the north pole, will give us also the latitude of the place.

The method of illustrating this phenomenon, is given in most treatises on the globe,

192. What popular error? 193. When is the pole star a safe guide for the surveyor CY mariner? What allowances should be made by each? 194. What said of finding the latitude by observations upon the pole star? What general rule stated? Wha frror ommitted?

and as adopted by teachers generally, is to tell the scholar that the north pole rise! nigher and higher, as he travels farther and farther toward it. In other words, what ever number of degrees he advances toward the north pole, so many degrees will it rise Above his horizon. This is not only an obvious error in principle, but it misleads the aprehension of the pupil. It is not that the pole is elevated, but that our horizon is depressed as we advance toward the north. The same objection lies against the artifi cial globe; for it ought to be so fixed that the horizon might be raised or depressed, and se pole remain in its own invariable position.

195. Ursa Minor contains twenty-four stars, including three f the 3d magnitude and four of the 4th. The seven principal stars are so situated as to form a figure very much resembling that in the Great Bear, only that the Dipper is reversed, and about one half as large as the one in that constellation.

196. The first star in the handle, called Polaris, is the polar star, around which the rest constantly revolve. The two last in the bowl of the Dipper, corresponding to the Pointers in the Great Bear, are of the 3d magnitude, and situated about 15° from the pole. The brightest of them is called Kochab, which signifies an axle or hinge, probably in reference to its moving so near the axis of the earth.

Kochab may be easily known by its being the brightest and middle one of the three conspicuous stars forming a row, one of which is about 2°, and the other 8° from Kochab. The two brighest of these are situated in the breast and shoulder of the animal, about 8° apart, and are called the Guards or Pointers of Ursa Minor. They are on the meridian about the 20th of June, but may be seen at all hours of the night, when the sky is clear.

197. Of the four stars which form the bowl of the Dipper, one is so small as hardly to be seen. They lie in a direction toward Gamma in Cepheus; but as they are continually changing their position in the heavens, they may be much better traced out from the map, than from description.

Kochab is about 25° distant from Benetnasch, and about 24° from Dubhe, and hence forms with them a very nearly equi lateral triangle.

"The Lesser Bear

Leads from the pole the lucid band: the stars
Which form this constellation, faintly shine,
Twice twelve in number; only one beams forth
Conspicuous in high splendor, named by Greece
The Cynosure; by us, the POLAR STAR."

HISTORY.

Le prevailing opinion is that Ursa Major and Ursa Minor are the nymph Calisto aud her sca Arcas, and that they were transformed into bears by the enraged and imperi un funo, and afterward translated to heaven by the favor of Jupiter, lest they migh: te Aestroyed by the huntsmen.

The Chinese claim that the emperor Hong-ti, the grandson of Noah, first discovered 196. De

195. Number of stars in Ursa Minor? Their magnitudes? How situated? scribe Polaris, Kochab, and the Guards or Pointers ? 197. Are all the stars distinctly visible? Direction? What triangle?

HISTORY.-What prevailing opinion, or myth? Chinese claim?

Phenicians? Greeks

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