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only three that are so large as the 3d magnitude. The largest of these, near the mouth, is in the solstitial colure, 1440 N. of Menkalina, in the E. shoulder of Auriga. The other two principal stars are in the brush of the tail, 340 S. W. of another star of the same brightness in the mouth of the Lesser Lion, with which it makes a small triangle. Its centre is on the meridian at 9 o'clock on the 23d, or at half past 7 on the 1st, of February

HISTORY -This constellation takes its name from a wild beast which is said to be of the genus of the wolf.

GEMINI.

THE TWINS. This constellation represents, in a sitting posture, the twin brothers, Castor and Pollux.)

Gemini is the third sign, but fourth constellation in the order of the Zodiac, and is situated south of the Lynx, between Cancer on the east, and Taurus on the west. The orbit of the earth passes through the centre of the constellation As the earth moves round in her orbit from the first point of Aries to the same point again, the sun, in the meantime, will appear to move through the opposite signs, or those which are situated right over against the earth, on the other side of her orbit.

Accordingly, if we could see the stars as the sun appeared to move by them, we should see it passing over the constellation Gemini between the 21st of June and the 23d of July but we seldom see more than a small part of any constellation through which the sun is then passing, because the feeble lustre of the stars is obscured by the superior effulgence of the

sun.

When the sun is just entering the outlines of a constellation on the east, its western limit may be seen in the morning twilight, just above the rising sun. So when the sun has arrived at the western limit of a constellation, the eastern part of it may be seen lingering in the evening twilight, just behind the setting sun Under other circumstances, when the sun is said to be in, or to enter, a particu lar constellation, it is to be understood that that constellation is not then visible, but that those opposite to it, are. For example: whatever constellation sets with the sun on any day, it is plain that the one opposite to it must be then rising, and continue visible through the night. Also, whatever constellation rises and sets with the sun to-day, will, six months hence, rise at sun-setting, and set at sun-rising. For example: the sun is in the centre of Gemini about the 6th of

Describe the position of the largest. Describe the position of the other two principal stars. What are their distance and direction from the one in the head? When is its centre on the meridian? Describe the position and appearance of the Twins. What is the relative position of Gemini among the signs and constellations of the Zodiac? How is the orbit of the earth situated, with respect to these constellations? How do the sun and earth appear to move through these signs? When does the sun appear to pass through the constellation Gemini? Do we usually see the constellations while the sun is passing through them? Under what circumstances can we see some part of them? When the sun is in or entering any constellation, are the opposite constella tions visible or not? If a constellation rise with the sun to-day, how will it rise six months hence? Give an example.

July, and must rise and set with it on that day; consequently, six months from that time, or about the 4th of January, it will rise in the east, just when the sun is setting in the west, and will come to the meridian at midnight; being then exactly opposite to the sun.

Now as the stars gain upon the sun at the rate of two hours every month, it follows that the centre of this constellation will, on the 17th of February, come to the meridian(three hours earlier) or at 9 o'clock in the evening.

It would be a pleasant exercise for students to propose questions to each other, somewhat like the following:-What zodiacal constellation will rise and set with the sun to-day? What one will rise at sun-setting? What constellation is three hours high at sun-set, and where will it be at 9 o'clock? What constellation rises two hours before the sun? How many days or months hence, and at what hour of the evening or morning, and in what part of the sky shall we see the constellation whose centre is now where the sun is ? &c., &c.

In solving these and similar questions, it may be remembered that the sun is in the vernal equinox about the 21st of March, from whence it advances through one sign or constellation every succeeding month thereafter; and that each constellation is one month in advance of the sign of that name: wherefore, reckon Pisces in March, Aries in April, Taurus in May, and Gemini in June, &c.; beginning with each constellation at the 21st, or 22d of the month.

Gemini contains 85 stars, including one of the 1st, one of the 2d, four of the 3d, and seven of the 4th magnitudes. It is readily recognised by means of the two principal stars, Castor and Pollux, of the 1st and 2d magnitudes, in the head of the Twins, about 41° apart.)

There being only 11 minutes' difference in the transit of these two stars over the meridian, they may both be considered as culminating (at 9 o'clock about the 24th of February, Castor, in the head of Castor, is a star of the 1st magnitude, 410 N. W. of Pollux, and is the northernmost and the brightest of the two.) (Pollux, is a star of the 2d magnitude, in the head of Pollux, and is 440 S. E. of Castor. (This is one of the stars from which the moon's distance is calculated in the Nautical Almanac.)

"Of the famed Ledean pair,

One most illustrious star adorns their sign,
And of the second order shine twin lights."

The relative magnitude or brightness of these stars has undergone considerable changes at different periods; whence it has been conjectured by various astronomers that Pollux must vary from the 1st to the 3d magnitude.) (But Herschel, who observed these stars for a period of 25 years, ascribes the variation to Castor, which he found to consist of two stars, very close together, the less revolving about the larger once in 342 years and two months.

Bradly and Maskelyne found that the line joining the two stars which form Castor was, at all times of the year, parallel to the line joining Castor and Pollux; and that both of the former move around a common centre between them, in

If a constellation come to the meridian at midnight to-day, how long before it will come to the meridian at 9 o'clock in the evening? If the constellation Gemini come to the meridian at midnight, on the 4th of January, when will it culminate at 9 o'clock? What is the number of stars in Gemini? By what means is it readily recognised? When do these stars culminate? Describe Castor. Describe Pollux. For what purpose is it observed at sea? Is the brightness of these two stars always the same? Who ascribes this variableness to Castor, and for what reason?

orbits nearly circular, as two balls attached to a rod would do, if suspended by a string affixed to the centre of gravity between them.

"These men," says Dr. Bowditch, "were endowed with a sharpness of vision, and a power of penetrating into space, almost unexampled in the history of astronomy."

About 20° S. W. of Castor and Pollux, and in a line nearly parallel with them, is a row of stars 30 or 40 apart, chiefly of the 3d and 4th magnitudes, which dis tinguish the feet of the twins. The brightest of these is Alhena, in Pollux's upper foot; the next small star S. of it, is in his other foot: the two upper stars in the line next above Gamma, mark Castor's feet.

(This row of feet is nearly two thirds of the distance from Pollux to Betelguese in Orion, and a line connecting them will pass through Alhena, the principal star in the feet. About two thirds of the distance from the two in the head to those in the feet, and nearly parallel with them, there is another row of three stars about 60 apart, which mark the knees.)

There are, in this constellation, two other remarkable parallel rows, lying at right angles with the former; one, leading from the head to the foot of Castor, the brightest star being in the middle, and in the knee; the other, leading from the head to the foot of Pollux, the brightest star, called Wasat. being in the body, and Zeta, next below it, in the knee.

Wasat is in the ecliptic, and very near the centre of the constellation. The two stars, Mu and Tejat, in the northern foot, are also very near the ecliptic;) Tejat is a sinall star of between the 4th and 5th magnitudes, 20 W. of Mu, and deserves to be noticed because it marks the spot of the summer solstice, in the tropic of Cancer, just where the sun is on the longest day of the year, and is, moreover, the dividing limit between the torrid and the N. temperate zone.

Propus, also in the ecliptic, 210 W. of Tejat, is a star of only the 5th magnitude, but rendered memorable as being the star which served for many years to determine the position of the planet Herschel, after its first discovery.

Thus as we pursue the study of the stars, we shall find continually new and more wonderful developments to engage our feelings and reward our labour. We shall have the peculiar satisfaction of reading the same volume that was spread out to the patriarchs and poets of other ages, of adiniring what they admired, and of being led as they were led, to look upon these lofty mansions of being as hav ing, above thein all, a common Father with ourselves, "who ruleth in the armies of heaven, and bringeth forth their hosts by number."

HISTORY.-Castor and Poilux were twin brothers, sons of Jupiter, by Leda, the wife of Tyndarus, king of Sparta. The manner of their birth was very sin gular. They were educated at Pallena, and afterwards embarked with Jason in the celebrated contest for the golden fleece, at Colchis; on which occasion they behaved with unparalleled courage and bravery. Pollux distinguished himself by his achievements in arms and personal prowess, and Castor in equestrian exercises and the management of horses. Whence they are represented, in the temples of Greece, on white horses, armed with spears, riding side by side, their heads crowned with a petasus, on whose top glittered a star. Among the ancients, and especially among the Romans, there prevailed a superstition that Castor and Pollux often appeared at the head of their armies, and led on their troops to battle and to victory.

"Castor and Pollux, first in martial force,

One bold on foot, and one renown'd for horse.

Fair Leda's twins in time to stars decreed,

One fought on foot, one curb'd the fiery steed."— Virgil.

"Castor alert to tame the foaming steed,

And Pollux strong to deal the manly deed."-Martial.

The brothers cleared the Hellespont and the neighbouring seas from pirates, after their return from Colchis; from which circumstance they have ever since been regarded as the friends and protectors of navigation. In the Argonautic expedition, during a violent storm, it is said two flames of fire were seen to play around their heads, and immediately the tempest ceased, and the sea was calni.

Describe the stars which mark the fect of the Twins. Specify the stars in each. How is this rm situated with respect to Orion? Describe the second row of stars in this constellation. Are there yet other rows in this constellation? Describe them. What is the position of Wasat? Two other stars are very near the ecliptic; mention them. Describe the position of Tejat. Give a description of the star Propus.

From this circumstance, the sailors inferred, that whenever both fires appeared in the sky, it would be fair weather: but when only one appeared, there would be storms.

St. Paul, after being wrecked on the island of Melita, embarked for Rome "in a ship whose sign was Castor and Pollux;" so formed, no doubt, in accordance with the popular belief that these divinities presided over the science and safety of navigation.

They were initiated into the sacred mysteries of Cabiri, and into those of Ceres and Eleusis. They were invited to a feast at which Lynceus and Idas were going to celebrate their nuptials with Phoebe and Telaria, the daughters of Leucippus, brother to Tyndarus. They becaine enamoured of the daughters, who were about to be married, and resolved to supplant their rivals: a battle ensued, in which Castor killed Lynceus, and was himself killed by Idas. Pollux revenged the death of his brother by killing Idas; but, being himself immortal, and most tenderly attached to his deceased brother, he was unwilling to survive him; he therefore entreated Jupiter to restore him to life, or to be deprived himself of immortality; wherefore, Jupiter permitted Castor, who had been slain, to share the immortality of Pollux; and consequently, as long as the one was upon earth, so long was the other detained in the infernal regions, and they alternately lived and died every day. Jupiter also further rewarded their fraternal attachment by changing thein both into a constellation under the name of Gemini, Twins, which, it is strangely pretended, never appear together, but when one rises the other sets, and so on alternately.

"By turns they visit this ethereal sky,

And live alternate, and alternate die."-Homer.

"Pollux, offering his alternate life,

Could free his brother, and could daily go

By turns aloft, by turns descend below."-Virgil.

Castor and Pollux were worshipped both by the Greeks and Romans, who sacrificed white lambs upon their altars. In the Hebrew Zodiac, the constellation of the Twins refers to the tribe of Benjamin.

CANIS MINOR.

+

THE LITTLE DOG. This small constellation is situated about 5° N. of the equinoctial, and midway between Canis Major and the Twins. It contains 14 stars, of which two are very brilliant. The brightest star is called Procyon. It is of the 1st magnitude, and is about 4° S. E. of the next brightest, marked Gomelza, which is of the 2d magnitude.

These two stars resemble the two in the head of the Twins. Procyon, in the Little Dog, is 23° S. of Pollux in Gemini, and Gomelza is about the same distance S. of Castor.

A great number of geometrical figures may be formed of the principal stars in the vicinity of the Little Dog. For example; Procyon is 23° S. of Pollux, and 26° E. of Betelguese, and forms with them a large right angled triangle. Again : Procyon is equidistant from Betelguese and Sirius, and forms with them an equilateral triangle whose sides are each about 26°. If a straight line, connecting Procyon and Sirius, be produced 23° farther, it will point out Phaet, in the Dove.

Describe the situation of Canis Minor. What is its whole number of stars? What is the magnitude of its principal ones? What is the brightest one called, and how is it situated? What other stars do Procyon and Gomelza resemble? What are the distance and direction of Procyon from Pollux? Of Gomelza from Castor? What are their distance and direction from Castor and Pollux? What kind of figures may be formed of the stars in the neighbourhood of the Little Dog! Give some examples.

(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 forerunner 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 Actæon'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.
Transforin'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 bis 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 constellation; 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 fangs 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?

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