About 10 S. W. of Ras Alhague are two small stars of the 4th magnitude. scarcely more than a degree apart. They distinguish the left or west shoulder. The northern one is marked Iota, and the other Kappa.

Eleven or twelve degrees S. S. E. of Ras Alhague are two other stars of the 3d magnitude, in the east shoulder, and about 20 apart. The upper one is called Cheleb, and the lower one Gamma. These stars in the head and shoulders of Serpentarius, form a triangle, with the vertex in Ras Alhague, and pointing towards the northeast.

About 4° E. of Gamma, is a remarkable cluster of four or five stars, in the form of the letter V, with the open part to the north. It very much resembles the Hyades. This beautiful little group marks the face of TAURUS PONIATOWSKI. The solstitial colure passes through the equinoctial about 2° E. of the lower star in the vertex of the V. The letter name of this star is k. There is something remarkable in its central position. It is situated almost exactly in the mid-heavens, being nearly equidistant from the poles, and midway between the vernal and autumnal equinoxes. It is, however, about one and a third degrees nearer the north than the south pole, and about two degrees nearer the autumnal than the vernal equi nox, being about two degrees west of the solstitial colure.

Directly south of the V, at the distance of about 120, are two very small stars, about 20 apart, situated in the right hand, where it grasps the serpent. About halfway between, and nearly in a line with, the two in the hand and the two in the shoulder, is another star of the 3d magnitude, marked Zeta, situated in the Serpent, opposite the right elbow. It may be known by means of a minute star, just under it.

Marsic, in the left arm, is a star of the 4th magnitude, about 10° S. W. of Iota and Cappa. About 7° farther in the same direction are two stars of the 3d mag nitude, situated in the hand, and a little more than a degree apart. The upper one of the two, which is about 16° N. of Graffias in Scorpio, is called Yed; the other is marked Epsilon. These two stars mark the other point in the folds of the monster where it is grasped by Serpentarius.

The left arm of Serpentarius may be easily traced by means of the two stars in the shoulder, the one (Marsic) near the elbow, and the two in the hand; all lying nearly in a line N. N. E. and S. S. W. In the same manner may the right arm be traced, by stars very similarly situated; that is to say, first by the two ir the east shoulder, just west of the V, thence 8° in a southerly direction in. clining a little to the east, by Zeta, (known by a little star right under it,) and then by the two small ones in the right hand, situated about 60 below Zeta.

About 12° from Antares, in an easterly direction, are two stars in the right foot, about 20 apart. The largest and lower of the two, is on the lefthand. It is of between the 3d and 4th magnitudes, and marked Rho. There are several other stars in this constellation of the 3d and 4th magnitudes. They may be traced out from the maps.

"Thee, Serpentarius, we behold distinct,

With seventy-four refulgent stars; and one
Graces thy helmet, of the second class:

The Serpent, in thy hand grasp'd, winds his spire
Immense; fewer by ten his figure trace;

Describe the stars in the west shoulder of Serpentarius. What stars distinguish the east shoulder? How are these two stars denominated? What is the relative position of the stars in the head and shoulders? What remarkable cluster of stars in this neighbourhood? To what constellation does this group belong? How is this cluster situated with respect to the solstitial colure? What is remarkable in the central position of Kappa? Describe the stars in the right hand of Serpentarius. Describe the situation of Zeta. Describe Marsic, and the two stars in the left hand. Which of the two is called Yed, and how is it situated? How may the left arm of Serpentarias be traced? How may the right arm be traced? Describe the stars in the right foot of Serpentarius. What other stars may be traced out in this constellation 2

One of the second rank; ten shun the sight;

And seven, he who bears the monster hides."-Eudosia.

HISTORY.-This constellation was known to the ancients twelve hundred years before the Christian era. Homer mentions it. It is thus referred to in the As tronomicon of Manilius:

"Next, Ophiuchus, strides the mighty snake,
Untwists his winding folds, and smooths his back,
Extends his bulk, and o'er the slippery scale
His wide-stretch'd hands on either side prevail.
The snake turns back his head, andeems to rage:
That war must last where equal power prevails."

Æsculapins was the son of Apollo, by Coronis, and was educated by Chiron the Centaur, in the art of medicine, in which he became so skilful, that he was considered the inventor and god of n.edicine. At the birth of Esculapius, the inspired daughter of Chiron uttered, "in sounding verse," this prophetic strain: "Hail, great physician of the world, all hail! Hail, mighty infant, who, in years to come, Shall heal the nations and defraud the tonib! Swift be thy growth! thy triumphs unconfined! Make kingdoms thicker, and increase mankind: Thy daring art shall animate the dead, And draw the thunder on thy guilty head: Then shalt thou die, but from the dark abode Rise up victorious, and be twice a god."

He accompanied the Argonauts to Colchis, in the capacity of physician. He is said to have restored many to life, insomuch that Pluto complained to Jupiter, that his dark dominion was in danger of being depopulated by his art.

Esculapins was worshipped at Epidaurus, a city of Peloponnesus, and hence he is styled by Milton, "the god in Epidaurus." Being sent for to Rome in the time of a plague, he assumed the form of a serpent and accompanied the ambas sadors, but though thus changed, he was Esculapius still, in serpente deus,— the deity in a serpent, and under that form he continued to be worshipped at Rome. The cock and the serpent were sacred to him, especially the latter. The ancient physicians used them in their prescriptions.

One of the last acts of Socrates, who is accounted the wisest and best man of Pagan antiquity, was to offer a cock to Esculapius. He, and Plato, were both idolaters; they conformed, and advised others to conforin, to the religion of their country; to gross idolatry and absurd superstition. If the wisest and must learn. ed were so blind, what must the foolish and ignorant have been?

CHAPTER X.

DIRECTIONS FOR TRACING THE CONSTELLATIONS WHICH ARE ON THE MERIDIAN IN AUGUST.

DRACO.

THE DRAGON.-This constellation, which compasses a large circuit in the polar regions by its ample folds and contortions, contains many stars which may be easily traced.

From the head of the monster, which is under the foot of Hercules, there is a complete coil tending eastwardly, about 17° N. of Lyra; thence he winds down northerly about 14°

What is the situation of the constellation Draco Doscribe, if you please, the vari ous coils of the Dragon.

to the second coil, where he reaches almost to the girdle of Cepheus, then he loops down somewhat in the shape of the letter U, and makes a third coil about 150 below the first. From the third coil he holds a westerly course for about 13°, then goes directly down, passing between the head of the Lesser and the tail of the Greater Bear.

This constellation contains eighty stars, including four of the 2d magnitude, seven of the 3d, and twelve of the 4th. "The Dragon next, winds like a mighty stream; Within its ample folds are eighty stars,

Four of the second order. Far he waves

His ample spires, involving either Bear."

The head of the Dragon is readily distinguished by means of four stars, 30, 40, and 5° apart, so situated as to form an irregular square; the two upper ones being the brightest, and both of the 2d magnitude. The righthand upper one, called Etanin, has been rendered very noted in modern astronomy from its connexion with the discovery of a new law in physical science, called the Aberration of Light.

The letter name of this star is Gamma, or Gamma Draconis; and by this appellation it is most frequently called. The other bright star, about 4° from it on the left, is Rastaben,

About 4° W. of Rastaben, a small star may, with close at tention, be discerned in the nose of the Dragon, which, with the irregular square before mentioned, makes a figure somewhat resembling an Italic V, with the point towards the west, and the open part towards the east. The small star in the nose, is called Er Rakis.

The two small stars 50 or 6° S. of Rastaben are in the left foot of Hercules.

Rastaben is on the meridian nearly at the same moment with Ras Alhague. Etanin, 40° N. of it, is on the meridian about the 4th of August, at the same time with the three western stars in the face of Taurus Poniatowski, or the V. It is situated less than 20 west of the solstitial colure, and is exactly in the zenith of London. Its favourable position has led English astronomers to watch its appearance, for long periods, with the most exact and unwearied scrutiny.

In the year 1725, Mr. Molyneux and Dr. Bradley fitted up a very accurate and costly instrument, in order to discover whether the fixed stars had any sensible parallax, while the earth moved from one extremity of its orbit to the other; or which is the same, to determine whether the nearest fixed stars are situated at such an immense distance from the earth, that any star which is seen this night directly north of us, will, six months hence, when we shall have gone 190 mill

What is the course of the monster from the third coil? What are the number and magnitude of the stars contained in this constellation? How is the head of the Dragon distinguished? Which star is called Etanin, and for what is it noted? By what other appellation is it generally known? What stars in the head of Draco form the letter V, and how is it situated? When is Rastaben on the meridian? When is Etanin on the meridian, and what stars in this region culminate at the same time? How is Rastaben situated with respect to the solstitial colure, and the zenith of London.

ions of miles to the eastward of the place we are now in, be then seen exactly north of us still, without changing its position so much as the thickness of a spi der's web.

These observations were subsequently repeated, with but little intermission, for twenty years, by the most acute observers in Europe, and with telescopes varying from 12 feet to 36 feet in length. In the meantime, Dr. Bradley had the honour of announcing to the world the very nice discovery, that the motion of light, combined with the progressive motion of the earth in its orbit, causes the heavenly bodies to be seen in a different position from what they would be, if the eye were at rest. Thus was established the principle of the Aberration of Light.

This principle, or law, now that it is ascertained, seems not only very plain. but self-evident. For if light be progressive, the position of the telescope, in order to receive the ray, must be different from what it would have been, if light had been instantaneous, or if the earth stood still. Hence the place to which the tel. escope is directed, will be different from the true place of the object.

The quantity of this aberration is determined by a simple proposition. The earth describes 59' 8" of her orbit in a day =3548", and a ray of light comes from the sun to us in 8' 13' 493": now 24 hours or 86400": 493" : : 3548": 22'; which is the change in the star's place, arising from the cause abovemen. tioned.

Of the four stars forming the irregular square in the head, the lower and righthand one is 50 N. of Etanin. It is called Grumium, and is of the 3d magnitude. A few degrees E. of the square, may be seen, with a little care, eight stars of the 5th magnitude, and one of the 4th, which is marked Omicron, and lies 8° E. of Grumium. This group is in the first coil of the Dragon.

The second coil is about 13° below the first, and may be recognised by means of four stars of the 3d and 4th magnitudes, so situated as to form a small square, about half the size of that in the head.

The brightest of them is on the left, and is marked Delta. A line drawn from Rastaben through Grumium, and produced about 140, will point it out. A line drawn from Lyra through Zi Draconis, and produced 10° further, will point out Zeta, a star of the 3d magnitude, situated in the third coil. Zeta may otherwise be known, by its being nearly in a line with, and midway between, Etanin and Kochab. From Zeta, the remaining stars in this constellation are easily traced. Eta, Theta, and Asich, come next; all stars of the 3d magnitude, and at the distance, severally, of 60, 40, and 50 from Zeta. At Asich, the third star from Zeta, the tail of the Dragon makes a sudden crook. Thuban, Kappa, and Gian. sar, follow next, and complete the tail.

Thuban, is a bright star of the 2d magnitude, 11° from Asich, in a line with, and about midway between, Mizar and the southernmost guard in the Little Bear. By nautical men this star is called the Dragon's Tail, and is considered of much importance at sea. It is otherwise celebrated as being formerly the north polar star. About 2,300 years before the Christian era, Thuban was ten times nearer the true pole of the heavens than Cynosura now is.

Kappa is a star of the 3d magnitude, 10° from Alpha, between Megrez and the pole. Mizar and Megrez, in the tail of the Great Bear, form, with Thuban and Kappa, in the tail of the Dragon, a large quadrilateral figure, whose longest side is from Megrez to Kappa.

Giansar, the last star in the tail, is between the 3d and 4tfi magnitudes, and 50 from Kappa. The two pointers will also point out Giansar, lying at the distance of little more than 80 from them, and in the direction of the pole.

Describe the stars in the first coil of Draco. Describe the stars in the second coil. What is the brightest of this group called, and how may it be pointed out? What is the principal star of the third coil, and how may it be found? How else may Zeta he known? What stars come next to Zeta, in this constellation? What stars follow these? Describe Thuban. By what other name is this star known, and for what is it celebrated? When was Thuban within ten minutes of the pole? Describe Kappa. What figure do Mizar and Megrez, in the tail of the Great Bear, form with Thuban and Kappa, in the tail of the Dragon? Describe the position of Giansar, and tell how it is pointed out.

"Here the vast Dragon twines
Between the Bears, and like a river winds,
The Bears, that still with fearful caution keep,
Untinged beneath the surface of the deep."

Warton's Virgil, G. i.

HISTORY.-Whoever attends to the situation of Draco, surrounding, as it does, the pole of the Ecliptic, will perceive that its tortuous windings are symbolical of the oblique course of the stars. Draco also winds round the pole of the world, as if to indicate, in the symbolical language of Egyptian astronomy, the motion of the pole of the Equator around the pole of the Ecliptic, produced by the precession of the heavens. The Egyptian hyeroglyphic for the heavens, was a 'serpent, whose scales denoted the stars. When astronomy first began to be cultivated in Chaidea, Draco was the polar constellation.

Mythologists, however, give various accounts of this constellation; by some it is represented as the watchful dragon which guarded the golden apples in the famous garden of the Hesperides, near Mount Atlas in Africa; and was slain by Hercules. Juno, who presented these apples to Jupiter on the day of their nup tials, took Draco up to heaven, and made a constellation of him, as a reward for his faithful services. Others maintain, that in the war with the giants, this dragon was brought into combat, and opposed to Minerva, who seized it in her hand, and hurled it, twisted as it was, into the heavens round the axis of the world, before it had time to unwind its contortions, where it sleeps to this day. Other writers of antiquity say, that this is the dragon killed by Cadmus, who was ordered by nis father to go in quest of his sister Europa, whom Jupiter had carried away and never to return to Phoenicia without her.

"When now Agenor had his daughter lost,
He sent his son to search on every coast;
And sternly bade him to his arms restore
The darling maid, or see his face no more."

His search, however, proving fruitless, he consulted the oracle of Apollo, and was ordered to build a city where he should see a heifer stop in the grass, and to call the country Boeotia. He saw the heifer according to the oracle, and as he wished to render thanks to the god by a sacrifice, he sent his companions to fetch water from a neighbouring grove. The waters were sacred to Mars, and guarded by a most terrific dragon, who devoured all the messengers. Cadmus, tired of their seeming delay, went to the place, and saw the monster still feeding on their flesh.

"Deep in the dreary den, conceal'd from day,
Sacred to Mars, a mighty dragon lay,
Bloated with poison to a monstrous size;

Fire broke in flashes when he glanced his eyes:

*Those who attempt to explain the mythology of the ancients, observe that the Hesperides were certain persons who had an immense number of flocks; and that the ambiguous Greek word penλov, melon, which sometimes signifies an apple and some. times a sheep, gave rise to the fable of the golden apple of these gardens.

The "Hesperian gardens famed of old," as Milton observes, were so called from Hesperus Vesper, because placed in the west, under the evening star. Some suppose them to have been situated near Mount Atlas, in Africa; others maintain that they were the isles about Cape Verd, whose most westerly point is still called Hesperium Cornu. the Horn of the Hesperides; while others contend, that they were the Canary Islands.

Atlas, said to have been contemporary with Moses, was king of Mauritania, in the north part of Africa, and owner of a thousand flocks of every kind. For refusing hospitality to Perseus, he was changed into the mountain that still bears his name; and which is so high, that the ancients imagined that the heavens rested upon its summit. and, consequently, that Atlas supported the world on his shoulders. Virgil has this idea, where he speaks of "Atlas, whose brawny back supports the skies;" and Hesiod, verse 785, advances the same notion

"Atlas, so hard necessity ordains,

Erect, the ponderous vault of stars sustains.
Not far from the Hesperides he stands.

Nor from the load retracts his head or hands."

From this very ancient and whimsical notion, Atlas is represented by artists, and in works of mythology, as an old man hearing the world on his shoulders. Hence it is that a collection of maps, embracing the whole world, is called an Atlas.