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into a constellation under the name of Gernini, Troins, 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 worshiped 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.
1. a GEMINORUM (Castor)-A neat DOUBLE STAR; R. A. 7h. 24m. 23s.; Dec. N. 32° 14': A 3. bright white; B 3%, pale white; with a third star of the 11th magnitude about 72" distant. A Binary System, with a probable period of 232 years. A beautiful object, and easily found. Map VIII., Fig. 4.
2. GEMINORUM -A QUADRUPLE STAR in the eye of Pollux, R. A. 7h. 35m. 31s.; Dec. N. 28° 25' 4". A 2, orange tinge; B 12, ash-colored; C 11, pale violet, with another minute companion visible with the best instruments.
3. y GEMINORUM (Alhena)—A coarse TRIPLE STAR, in the right foot of Pollux; R. A. 6h. 28m. 28s.; Dec. N. 16° 31' 8".; A 3, brilliant white; B 13, and C 12, both pale plum color. It is on a line from Rigel to 3 Geminorum, and nearest the former.
4. GEMINORUM (Wasat)-A DOUBLE STAR on the right hip of Pollux; R. A. 7h. 10m. 348.; Dec. N. 22° 16' 3". Á 3%, pale white; B 9, purple.
5. & GEMINORUM (Melucta)—A star with a distant companion, on Castor's right knee, R. A. 6h. 34m. 05s.; Dec. N. 25° 16' 9". A 3, white; B 91⁄2, cerulean blue.
6. GEMINORUM-A coarse TRIPLE STAR on the right knee of Pollux; R. A. 6h. 54m. 37s. ; Dec. N. 20° 47' 9". A 4, pale topaz; B 8, violet; C 13, grey.
7. A CLUSTER, near the right foot of Castor; R. A. 5h. 59m. 01s.; Dec. N. 24° 21′ 8′′. A gorgeous field of stars from the 9th to the 16th magnitudes.
8. A CLUSTER in the calf of Pollux's right leg; R. A. 6h. 45m. 56s.; Dec. N. 18° 10′ 5′′. A faint angular group of extremely small stars, in a rich region, but seen with difficulty. See Map VIII., Fig. 35.
9. A COMPRESSED CLUSTER under the left shoulder of Pollux; one-third the distance from Geminorum, to 3 Canis Minoris; R. A. 7h. 28m. 57s.; Dec. N. 21° 55′ 7′′. A faint object about 12 in diameter, with a small star near the centre. Map VIII., Fig. 36.
CANIS MINOR (THE LITTLE DOG).—MAP III.
99. 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 3d 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.
100. 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 Betel
TELESCOPIC OBJECTS.-Alpha? Beta? Gamma? Delta, &c.? Clusters? Which shown on the map?
99. Where is Canis Minor situated? Number of stars? nitude? Next brightest? What do these two resemble? trical figures? Of the name Procyon? Its import?
Name of brightest? Mag100. What said of geome
guese, and forms with them a large right-angled triangle. Again, Procyon is equi-distant 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.
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."
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.
But as by chance, witin a neighb'ring brook,
He tried to speak, but only gave a groan;
Tore the sad huntsman groveling on the ground."
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 philanthropist, 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.
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 particular 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.
1. a CANIS MINORIS (Procyon)—A bright star in the loins of the dog with a distant ompanion; R. A. 7h. 30m. 55s; Dec. N. 5° 37' 8". A 1%, yellowish white; B 8, orange ant. Several small stars in the field.
HISTORY.-What is the Little Dog supposed to represent? Fable of Acteon?
2. 6 CANIS MINORIS (Gomelza)-A wide TRIPLE STAR in theneck; R. A. 7h. 18m. 28s.; Dec. N. 8° 36' 4". A 3, white; B 12, orange; C 10, flushed-the last coarsely double with one of the same magnitude. Other stars in the field.
3. A close DOUBLE STAR, in a fine vicinity in the loins; R. A. 7h. 31m. 87s.; Dec. N. 5° 85' 7". A 7, white; B 8, ash-colored, with a minute blue star 2' distant.
4. A WIDE TRIPLE STAR, 6° S. E. of Procyon; R. A. 7h. 50m. 08s.; Dec. N. 2° 38′ 8′′. A 6, pale white; B 8, bluish; C 9, blue.
MONOCEROS (THE UNICORN).-—MAP III.
101. This is a modern constellation, 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.
102. 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 Albena 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.
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 a 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
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.
1. A most delicate DOUBLE STAR (ƒ), in the Unicorn's eye; R. A. 6h. 26m. 06s.; Dec. N. 7° 41′ 05′′. A 6, yellowish white: B 16, dusky. A difficult object.
2. A neat DOUBLE STAR (b), in the nostril, 7' east of Betelguese; R. A. 6h. 15m. 17s.; Dec. N. 4° 40' 01". A 5%, golden yellow; B 8, lilac.
3. A fine TRIPLE STAR in the right fore-leg; R. A. 6h. 21m. 04s.; Dec. S. 6° 56′ 01′′. A 6%, white; B 7, and C 8, both pale white. A ray shot from the Bull's eye through Bellatrix, and rather more than as far again, will pick it up. Supposed by Herschel to be a triple system, periods A B 17,000 ys. B C 1000. Shown double only on the map of the constellations. Telescopic view, Map VIII., Fig. 5.
4. A delicate TRIPLE STAR, in a magnificent stellar field, between the Unicorn's ears; R. A. 6h. 32m. 10s.; Dec. N. 10° 02' 02". One-third the distance from Procyon to Aldebaran. A 6, greenish; B 9%, pale grey; C 15, blue. A fine object.
102. Number and size of its
101. Character and situation of Monoceros? Extent? stars? How three of the largest situated? HISTORY.-What said of the animal itself? Is it not wholly fabulous? TELESCOPIC OBJECTS.-Double stars? Triple? Any shown on the map?
CANIS MAJOR (THE GREAT DOG).-MAP III.
103. This interesting constellation is situated 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 unequaled 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.
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 32 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?
104. In the remote ages of the world, when every man was his own astronomer, the rising and setting of Sirius, or the Dog Star, 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.
105. 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:
"Tum steriles exurere Sirius agros;
Ardebant herbæ, et victum seges ægra negabat."
"Parched was the grass, and blighted was the corn:
103. Situation of Canis Major? How known? Supposed distance of Sirius? Illustrated by the speed of a cannon ball? Of light? ancients? Use made of it by the Thebans? Romans?
104. How was Sirius regarded by the The Egyptians? 105. Practice of the
106. 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 Dog-days, (Dies canicularis.) At that remote period the Dog-days 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.
107. 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.
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 of 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°: 50%=2794 years since the time of Hesiod, which corresponds very nearly with history.
108. When a star rose at sun-setting, or set at sun-rising, it was called the Achronical 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 12° below the horizon; stars of the 2u magnitude require the sun's depression to be 18°; 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 allotted to the several departments of husbandry, and the overflowing of the Nile.
109. 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,
106. Origin of the phrase Dog-days? When did they begin in the time of Virgil? At what time now? 107. What inference from these facts? What variation in the time of Sirius' rising? What calculation by knowing the time when Sirius rose, at any period? 108. What are the Achronical and Heliacal rising or setting of a star or planet? Remark of Ptolemy in regard to rising and setting of the stars? 109. How is it that Sirius, a winter star, is associated with the heat of summer?