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Procyon is often taken for the name of the Little Dog, or for the whole constellation, as Sirius is for the greater one; hence it is common to refer to either of these constellations by the name of its principal star. Procyon comes to the meridian 53 minutes after Sirius, on the 24th of February; although it rises, in this latitude, about half an hour before it. For this reason, it was called Procyon, from two Greek words which signify (Ante Canis) "before the dog."

"Canicula, fourteen thy stars; but far

Above them all, illustrious through the skies,
Beams Procyon; justly by Greece thus called
The bright jorerunner of the greater Dog."

HISTORY.-The Little Dog, according to Greek fable, is one of Orion's hounds. Some suppose it refers to the Egyptian god Anubis, which was represented with a dog's head: others to Diana, the goddess of hunting; and others, that it is the faithful dog Mæra, which belonged to Icarus, and discovered to his daughter Erigone the place of his burial. Others, again, say it is one of Acteon's hounds that devoured their master, after Diana had transformed him into a stag, to prevent, as she said, his betraying her.

"This said, the man began to disappear
By slow degrees, and ended in a deer.
Transform'd at length, he flies away in haste,
And wonders why he flies so fast.

But as by chance, within a neighb'ring brook,
He saw his branching horns, and alter'd look,
Wretched Actæon! in a doleful tone
He tried to speak, but only gave a groan;
And as he wept, within the watery glass,
He saw the big round drops, with silent pace,
Run trickling down a savage, hairy face.
What should he do? or seek his old abodes,
Or herd among the deer, and skulk in woods?
As he thus ponders, he behind him spies
His opening hounds, and now he hears their cries.
From shouting men, and horns, and dogs, he flies.
When now the fleetest of the pack that press'd
Close at his heels, and sprung before the rest,
Had fasten'd on him, straight another pair
Hung on his wounded side, and held him there,
Till all the pack came up, and every hound

Tore the sad huntsman grovelling on the ground."*

It is most probable, however, that the Egyptians were the inventors of this con stellation; and as it always rises a little before the Dog-star, which, at a particu lar season, they so much dreaded, it is properly represented as a little watchful creature, giving notice like a faithful sentinel of the other's approach.

*It is not difficult to deduce the moral of this fable. The selfishness and caprice of human friendship furnish daily illustrations of it. While the good man, the philan thropist, or the public benefactor, is in affluent circumstances, and, with a heart to devise, has the power to minister blessings to his numerous beneficiaries, his virtues are the general theme: but when adverse storms have changed the ability, though they could not shake the will of their benefactor, he is straightway pursued, like Actæon, by his own hounds; and, like Actæon, he is "torn to the ground" by the fungs that fed upon his bounty.-L. Q. C. L.

What name is usually given to the Little Dog? When does Procyon rise and culmi nate, with respect to the Dog-star? What name, for this reason, was given to this constellation?

MONOCEROS.

THE UNICORN.-This is a modern constellation, which was made out of the unformed stars of the ancients that lay scattered over a large space of the heavens between the two Dogs. It extends a considerable distance on each side of the equinoctial, and its centre is on the same meridian with Procyon.

It contains 31 small stars, of which the seven principal ones are of only the 4th magnitude. Three of these are situated in the head, 3° or 4° apart, forming a straight line N. E. and S. W about 9° E. of Betelguese in Orion's shoulder, and about the same distance S. of Alhena in the foot of the Twins.

The remaining stars in this constellation are scattered over a large space, and being very small, are unworthy of particular notice.

HISTORY. THE MONOCEROS is a species of the Unicorn or Rhinoceros. It is about the size of a horse, with one white horn growing out of the middle of its forehead. It is said to exist in the wilds of Ethiopia, and to be very formidable. Naturalists say that, when pursued by the hunters, it precipitates itself from the tops of the highest rocks, and pitches upon its horn, which sustains the whole force of its fall, so that it receives no damage thereby. Sparmann informs us, that the figure of the unicorn, described by some of the ancients, has been found delineated on the surface of the rock in Caffraria; and thence conjectures that such an animal, instead of being fabulous, as some suppose, did once actually exist in Africa. Lobo affirms that he has seen it.

The rhinoceros, which is akin to it, is found in Bengal, Siam, Cochin China, part of China Proper, and the isles of Java and Sumatra.

CANIS MAJOR.

THE GREAT DOG.-This interesting constellation is situa'ed southward and eastward of Orion, and is universally Known by the brilliance of its principal star, Sirius, which is apparently the largest and brightest in the heavens. It glows in the winter hemisphere with a lustre which is unequalled by any other star in the firmament.

Its distance from the earth, though computed at 20 millions of millions of miles, is supposed to be less than that of any other star: a distance, however, so great that a cannon ball, which flies at the rate of 19 miles a minute, would be two millions of years in passing over the mighty interval; while sound, moving at the rate of 13 miles a minute, would reach Sirius in little less than three millions of years.

What stars compose the constellation Monoceros? How is this constellation situated, and when is it on the meridian? What is the whole number of its stars? What is the magnitude of its principal ones? Describe those in the head. Describe the position and appearance of Canis Major. What is its appearance in the winter? What Is its distance froin the earth computed to be, and how is it compared with that of the other stars? How long would it take a cannon-ball to pass over this distance In what time would sound reach Sirius from the earth?

It may be shown in the same manner, that a ray of light, which occupies only 8 minutes and 13 seconds in coming to us from the sun, which is at the rate of nearly two hundred thousand miles a second, would be 3 years and 82 days in passing through the vast space that lies between Sirius and the earth. Consequently, were it blotted from the heavens, its light would continue visible to us for a period of 3 years and 82 days after it had ceased to be.

If the nearest stars give such astonishing results, what shall we say of those which are situated a thousand times as far beyond these, as these are from us? In the remote ages of the world, when every man was his own astronomer, the rising and setting of Sirius, or the Dogstar, as it is called, was watched with deep and various solicitude. The ancient Thebans, who first cultivated astronomy in Egypt, determined the length of the year by the number of its risings. The Egyptians watched its rising with mingled apprehensions of hope and fear; as it was ominous to them of agricultural prosperity or blighting drought. It foretold to them the rising of the Nile, which they called Siris, and admonished them when to sow. The Romans were accustomed yearly, to sacrifice a dog to Sirius to render him propitious in his influence upon their herds and fields. The eastern nations generally believed the rising of Sirius would be productive of great heat on the earth.

Thus Virgil:

"Tuni steriles exurere Sirius agros:

Ardebant herbæ, et victum seges ægra negabat."

"Parched was the grass, and blighted was the corn:
Nor 'scape the beasts; for Sirius, from on high,
With pestilential heat infects the sky."

Accordingly, to that season of the year when Sirius rose with the sun and seemed to blend its own influence with the heat of that luminary, the ancients gave the name of Dogdays, (Dies Caniculares). At that remote period the Dogdays commenced on the 4th of August, or four days after the summer solstice, and lasted forty days or until the 14th of September. At present the Dog-days begin on the 3d of July, and continue to the 11th of August, being one day less than the ancients reckoned.

Hence, it is plain that the Dog-days of the moderns have no reference whatever to the rising of Sirius, or any other star, because the time of their rising is perpetually accelerated by the precession of the equinoxes: they have reference then only to the summer solstice which never changes its position in respect to the seasons.

How long is light in coming from Sirius to the earth? Suppose this star were now to be blotted from the heavens, how long before its twinkling would expire? How was the rising of Sirius regarded in the remote ages of the world? What use was made of it by the ancient Thebans? How did the Egyptians regard it, and for what reason? What did it foretel to them? What did the Romans offer in sacrifice to Sirius annually? Why? How was it regarded by the eastern nations generally? What season of the year di the ancients call Dog-days? When did these begin, and how long did they last? At present, when do they begin and end Have our Dog-days any reference to the Dog-star?

The time of Sirius' rising varies with the latitude of the place, and in the same latitude, is sensibly changed after a course of years, on account of the precession at the equinoxes. This enables us, to determine with approximate accuracy, the dates of many events of antiquity, which cannot be well determined by other records. We do not know, for instance, in what precise period of the world Hesiod flourished. Yet he tells us, in his Opera et Dies, lib. ii. v. 185, that Arcturus in his time rose heliacally, 60 days after the winter solstice, which, then was in the 9th degree of Aquarius, or 39° beyond its present position. Now 39° 504"-2794 years since the time of Hesiod, which corresponds very nearly with history.

When a star rose at sun-setting, or set at sun-rising, it was called the Achroni cal rising or setting. When a planet or star appeared above the horizon just before the sun, in the morning, it was called the Heliacal rising of the star; and when it sunk below the horizon immediately after the sun, in the evening, it was called the Heliacal setting. According to Ptolemy, stars of the first magnitude are seen rising and setting when the sun is 120 below the horizon; stars of the 2d magnitude require the sun's depression to be 13°; stars of the 3d magnitude, 14°, and so on, allowing one degree for each magnitude. The rising and setting of the stars described in this way, since this mode of description often occurs in Hesiod, Virgil, Columella, Ovid, Pliny, &c. are called poetical rising and setting. They served to mark the times of religious ceremonies, the seasons al lotted to the several departments of husbandry, and the overflowing of Nile

The student may be perplexed to understand how the Dog-star, which he seldom sees till mid-winter, should be associated with the most fervid heat of summer. This is explained by considering that this star, in summer, is over our heads in the daytime, and in the lower hemisphere at night. As "thick the floor of heaven is inlaid with patines of bright gold," by day, as by night; but on account of the superior splendour of the sun, we cannot see them.

Sirius is situated nearly S. of Alhena, in the feet of the Twins, and about as far S. of the equinoctial as Alhena is N. of it. It is about 10° E. of the Hare, and 26° S. of Be telguese in Orion, with which it forms a large equilateral triangle. It also forms a similar triangle with Phaet in the Dove, and Naos in the Ship. These two triangles being joined at their vertex in Sirius, present the figure of an enormous X, called by some, the EGYPTIAN X. Sirius is also pointed out by the direction of the Three Stars in the belt of Orion. Its distance from them is about 23°. It comes to the meridian at 9 o'clock on the 11th of February.

Mirzam, in the foot of the Dog, is a star of the 2d magnitude, 540 W. of Sirius. A little above, and 4° or 5° to the left, there are three stars of the 3d and 4th magnitudes, forming a triangular figure somewhat resembling a dog's head.

What is meant by the Achronical rising and setting of the stars? What, by their Heliacal rising and setting? By whom were the terms thus applied, and what were these risings and settings called? What did they serve? Explain how it is, that the Dog-star, which is seldom seen till mid-winter, should be associated with the most fervid heat of summer. Are there as many stars over our head in the daytime as in the night? Describe the situation of Sirius. What is its position with regard to Betelguese and Procyon, and in connexion with them what figure does it form? With what other stars does it form a similar triangle? What is the appearance of these two triangles taken together? How else is Sirius pointed out? Describe the position and magnituule of Mirzam. What stars mark the head of the Dog?

The brightest of them, on the left, is called Muliphen. It entirely disappeared in 1670, and was not seen again for more than 20 years. Since that time it has maintained a steady lustre.

Wesen is a star of between the 2d and 3d magnitudes, in the back, 11° S. S. E. of Sirius, with which, and Mirzam in the paw, it makes an elongated triangle. The two hinder feet are marked by Naos and Lambda, stars of the 3d and 4th magnitudes, situated about 3° apart, and 12° directly S. of the fore foot. This constellation contains 31 visible stars, including one of the 1st magnitude, four of the 2d, and two of the 3d; all of which are easily traced out by the aid of the map.

HISTORY.-Manilius, a Latin poet who flourished in the Augustan age, wrote an admirable poem, in five books, upon the fixed stars in which he thus speaks of this constellation:

"All others he excels; no fairer light

Ascends the skies, none sets so clear and bright.”

But EUDOSIA best describes it :

"Next shines the Dog with sixty-four distinct;
Fain'd for pre-eminence in envied song,
Theme of Homeric and Virgilian lays:

His fierce mouth flames with dreaded Sirius ;
Three of his stars retire with feeble beams."

According to some mythologists, this constellation represents one of Orion' hounds, which was placed in the sky, near this celebrated huntsman. Others say it received its name in honour of the dog given by Aurora to Cephalus, which surpassed in speed all the animals of his species. Cephalus, it is said at tempted to prove this by running him against a fox, which, at that time, was thought to be the fleetest of all animals. After they had run together a long tine without either of them obtaining the victory, it is said that Jupiter was so much gratified at the fleetness of the dog that he assigned him a place in the heavens.

But the name and form of this constellation are, no doudt, derived from the Egyptians, who, carefully watched its rising, and by it judged of the swelling of the Nile, which they called Siris, and, in their hieroglyphical manner of writing, since it was as it were the sentinel and watch of the year, represented it under the figure of a dog. They observed that when Sirius became visible in the east, just before the morning dawn, the overflowing of the Nile immediately followed. Thus it warned them, like a faithful dog, to escane from the region of the inun dation.

CHAPTER V.

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

ARGO NAVIS.

THE SHIP ARGO.-This constellation occupies a large space in the southern hemisphere, though but a small part of it can

Which is the brightest of these, and what remarkable circumstance in its history? How has it appeared since its return? Describe the situation and magnitude of Wesen? What stars mark the hinder feet? What is the number of visible stars in this constellation Describe the constellation Argo Navis?

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