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Science struck out into systems very bold; and the spirit of infidelity, seizing upon the discovery, flattered itself with the hope of drawing from thence new support. It was unjustifiably taken for granted, that the ruins of Egypt furnished astronomy with monuments, containing observations that exhibited the state of the heavens in the most remote periods. Starting with this assumption, a pretence was made of demonstrating by means of calculations received as infallible, that the celestial appearances assigned to these monuments extended back from forty-five to sixty-five centuries; that the Zodiacal system to which they must belong, dated back fifteen thousand years, and must reach far beyond the limits assigned by Moses to the existence of the world." Among those who stood forth more or less bold as the adversaries of Revelation, the most prominent was M. Dupuis, the famous author of L'origine de tous les Cultes.

The infidelity of Dupuis was spread about by means of pamphlets, and the advocates of the Mosaic account were scandalized "until a new Alexander arose to cut the Gordian knot, which men had vainly sought to untie. This was Champollion the younger, armed with his discovery." The hieroglyphics now speak a language that all can understand, and no one gainsay. "The Egyptian Zodiacs, then," says Latronne, "relate in no respect to astronomy, but to the idle phantasies of judicial astrology, as connected with the des tinies of the emperors who made or completed them."

TELESCOPIC OBJECTS.

1. a ARIETIS A DOUBLE STAR in the Ram's forehead; R. A. 1h. 58m. 10s; Dec. N. 22° 42' 02". A 3, yellow; B 11, purple.

Two thousand years ago the first meridian or Vernal Equinox passed through th star; but the recession of the equinox at the slow rate of 50" per year, has, in that length of time, carried the equinoctial nearly 60° to the west, where we now find it. See thi subject explained in the second part of the book.

2. B ARIETIS (Sheratan)—A BRIGHT STAR with a distant companion in the coil of the right horn; R. A. 1h. 45m. 49s.; Dec. N. 20° 01' 04". A 8, pearly white; B 11, dusky. 3. Y ARIETIS (Mesarthim)—a DOUBLE STAR just south of 3; R. A. 1h. 44m. 45s.; Dec. N. 18° 30′ 05′′. A 4%, bright white; B 5, pale grey. A fine object. Map VIII., Fig. 2.

4. & ARIETIS A VERY CLOSE DOUBLE STAR near the root of the tail, and between it and Musca; R. A. 2h. 50m. 04s.; Dec. N. 20° 41′ 08′′. A 5, pale yellow; B 6%, whitish. It requires a good telescope to soparate them.

5. π ARIETIS-A neat TRIPLE STAR in the haunch, about one-third of the distance from B Arietis to Aldebaran; R. A. 2h. 40m. 22s.; Dec. N. 16° 47′ 08′′. A 5, pale yellow; B 8%, flushed; C 11, dusky. A beautiful trio.

6. A QUADRUPLE STAR half way between a and y under the right horn; R. A. 1h. 50m. 43s.; Dec. N. 20° 16′ 07". A 6, topaz yellow; B 15, deep blue; C 10, lilac; D, pale blue. An exquisite object.

7. A ROUND NEBULA near y Arietis, and just east of it; R. A. 1h. 50m. 34s.; Dec. N 18° 13' 06". It is large and pale, and lies among some small stars, some of which form a curve across the south part of the field.

TRIANGULÆ

(THE TRIANGLES).—MAP II.

52. The Triangles are situated between the head of Aries on the north, and the feet of Andromeda on the south. R. A. 2h.; Dec. N. 30°. They contain two stars of the 4th magnitude, and two of the 5th; with several smaller. A line from Sheratan in Aries, to Almaack, will pass through the lucida Trianguli, about midway between them.

TELESCOPIC OBJECTS? What a Arietis? Other double stars? Triple? Quadruple? Any clusters? Nebulæ?

52. Situation of the Triangles? Number and size of stars? How find their lucida?

HISTORY.

The upper or Northern Triangle is one of the ancient 48 asterisms; and Hevelius took three other stars between it and the head of Aries, to form Triangulum minus. The latter figure, however, is discontinued, though shown on the map.

TELESCOPIC OBJECTS.

1 a TRIANGULI-A bright FOURTH MAGNITUDE STAR, with a Telescopic companion; R. A 1h. 43m. 58s.; Dec. N. 28° 47' 08". A 3%, yellow; B 11, lilac.

2. & TRIANGULI-A MOST DELICATE DOUBLE STAR; R. A. 1h. 53m. 38s.: Dec. N. 32° 30′ 05′′. A 5%, bright yellow; B 15, dusky.

8. A large and distinct but faint PALE WHITE NEBULA, between the Triangles and the head of the Northern Fish; R. A. 1h, 24m. 51s.; Dec. N. 29° 51' 03". A bright star a little north-west, and five others more remote in the east.

MUSCA (THE FLY).—MAP II.

53. This very small constellation lies directly between the back of Aries on the south, and the head of Medusa on the north. It has one star of the 2d, two of the 4th, and two of the 5th magnitudes. An unimportant asterism, and not always mentioned in the catalogues, though shown on the map.

TELESCOPIC OBJECTS.

1. A FINE DOUBLE STAR Over the back of Aries, nearly midway between the Pleiades and B Andromedæ; R. A. 2h. 31m. 20s.; Dec. N. 26° 22' 02". A 6, pale topaz; B 9, light blue. An easy object.

2. a MUSCA-a COARSE QUADRUPLE STAR, in the body of the figure, and forming its lucida; R. A. 2h. 40m. 34s.; Dec. N. 26° 35' 09". A 3, white; B 13, deep blue; C 11, lurid; D 9, pale grey. Both these objects are usually classed as belonging to Aries.

CETUS (THE WHALE).-MAP II.

54. As the whale is the chief monster of the deep, and the largest of the aquatic race, so is it the largest constellation in the heavens. It occupies a space of 50° in length, E. and W., with a mean breadth of 20° from N. to S. It is situated below Aries and the Triangles, with a mean declination of 12° S. It is represented as making its way to the E., with its body below, and its head elevated above the equinoctial; and is six weeks in passing the meridian. Its tail comes to the meridian on the 10th of November, and its head leaves it on the 22d of December. 55. This constellation contains 97 stars; two of the 2d magnitude, ten of the 3d, and nine of the 4th.' The head of Cetus

HISTORY.-Which ancient? Who formed the other? Now recognized, or not? TELESCOPIC OBJECTS? Double stars? Nebulæ? 58. Situation of Musca? Stars? Relative importance? Is it always recognized as a constellation? 54. Cetus? Comparative size? Situation? How represented? 55. Number of stars Magnitudes? How may the head of Cetus be known? Brightest

may be readily distinguished, about 20° S. E. of Aries, by means of five remarkable stars, 4° and 5° apart, and so situated as to form a regular pentagon. The brightest of these is Menkar, of the 2d magnitude, in the nose of the Whale. It occupies the S. E. angle of the figure. It is 34° N. of the equinoctial, and 15° E. of El Rischa in the bight of the cord between the Two Fishes. It is directly 37° S. of Algol, and nearly in the same direction from the Fly. It makes an equilateral triangle with Arietis and the Pleiades, being distant from each about 23° S., and may otherwise be known by a star of the 3d magnitude in the mouth, 3° W. of it, called Gamma, placed in the south middle angle of the pentagon.

56. Nu is a star of the 4th magnitude, 4° N. W. of Gamma, and these two constitute the S. W. side of the pentagon in the head of the Whale, and the N. E. side of a similar oblong figure in the neck.

Three degrees S. S. W. of Gamma, is another star of the 3d magnitude in the lower jaw, marked Delta, constituting the E. side of the oblong pentagon; and 6° S. W. of this, is a noted star in the neck of the Whale, called Mira, or the "wonderful star of 1596," which forms the S. E. side. This variable star was first noticed as such by Fabricius, on the 13th of August, 1596. It changes from a star of the 2d magnitude so as to become invisible once in 234 days, or about 7 times in 6 years. Herschel makes its period 331 days, 10 hours, and 19 minutes ; while Hevelius assures us that it once disappeared for 4 years; so that its true period, perhaps, has not been satisfactorily determined.

The whole number of stars ascertained to be variable amounts to only 15; while those which are suspected to be variable, amount to 87.

57. Mira is 7° S. S. E. of El Rischa, in the bend or knot of the ribbon which connects the Two Fishes. Ten degrees S. of Mira, are 4 small stars, in the breast and paws, about 3° apart, which form a square, the brightest being on the E. Ten degrees S. W. of Mira is a star of the 3d magnitude, in the heart, called Baten Kaitos, which makes a scalenę triangle with two other stars of the same magnitude 7° and 10° W. of it; also, an equilateral triangle with Mira and the easternmost one in the square.

star? Position? Name? 56. Size and Position of Nu? Delta? Mira? Position? Peculiarity? When, and by whom first noticed? Period and extent of variability f Whole number of variable stars? 57. Baten Kaitos? Position with regard to Mira. To other stars?

A great number of geometrical figures may be formed from the stars in this, and in most of the other constellations, merely by reference to the maps; but it is better that the student should exercise his own ingenuity in this way with reference to the stars themselves, for when once he has constructed a group into any letter or figure of his own invention, he never will forget it.

The teacher should therefore require his class to commit to writing the result of their own observations upon the relative position, magnitude and figures of the principal stars in each constellation. One evening's exercise in this way will disclose to the student a surprising multitude of crosses, squares, triangles, arcs and letters, by which he will be better able to identify and remember them, than by any instructions that could be given. For example: Mira and Baten in the Whale, about 10° apart, make up the S. E. or shorter side of an irregular square, with El Rischa in the node of the ribbon, and another star in the Whale as far to the right of Baten, as El Rischa is above Mira. Again,

There are three stars of equal magnitude, forming a straight line W. of Baten; from which, to the middle star is 10°, thence to the W. one 12%; and 8° or 9° S. of this line, in a triangular direction, is a bright star of the second magnitude in the coil of the tail, called Diphda.

In a southerly direction, 25° below Diphda, is Alpha in the head of the Phenix, and about the same distance S. W. is Fomalhaut, in the mouth of the Southern Fish, forming together a large triangle, with Diphda in the vertex or top of it.

That fine cluster of small stars S. of the little square in the Whale, constitutes a part of a new constellation called the Chymical Furnace. The two stars N. E., and the three to the southward of the little square, are in the river Eridanus.

HISTORY.

This constellation is of very early antiquity: though most writers consider it the famous sea-monster sent by Neptune to devour Andromeda because her mother Cassiopeia had boasted herself fairer than Juno or the Sea Nymphs; but slain by Perseus and placed among the stars in honor of his achievement.

"The winged hero now descends, now soars,
And at his pleasure the vast monster gores.
Deep in his back, swift stooping from above,
His crooked sabre to the hilt he drove."

It is quite certain, however, that this constellation had a place in the heavens long prior to the time of Perseus. When the equinoctial sun in Aries, which is right over the head of Cetus, opened the year, it was denominated the Preserver, or Deliverer, by the idolaters of the East. On this account, according to Pausanius, the sun was worshipped, at Eleusis, under the name of the Preserver or Saviour.

"With gills pulmonic breathes the enormous whale,

And spouts aquatic columns to the gale;

Sports on the shining wave at noontide hours,

And shifting rainbows crest the rising showers."-Darwin.

TELESCOPIC OBJECTS.

1. 6 CETI-A DOUBLE STAR; R. A. Oh. 35m. 34s.; Dec. S. 18° 51′ 9′′. A 2%, yellow; B 12, pale blue.

2. Y CETI A CLOSE DOUBLE STAR in the Whale's mouth; R. A. 2h. 35m. 01s.; Dec. N. 2° 33' 5". A 3, pale yellow; B 7, lucid blue; the colors finely contrasted.

3. v A DOUBLE STAR in the Whale's eye; y R. A. 2h. 27m. 29s.; Dec. N. 4° 58′ 5′′. A 42, pale yellow; B 15, blue.

4. A LONG NARROW NEBULA, of a pale, milky tint; R. A. 0h. 39m. 45s.; Dec. S. 26° 10' 1". It is situated in the space south of the tail of Cetus, near a line drawn from a Andromeda to ẞ Ceti. Discovered by Miss Herschel, in 1783.

5. A PLANETARY NEBULA; R. A. 2h. 19m. 25s.; Dec. S. 1° 51' 6"; in the middle of the Whale's neck.

6. A BRIGHT ROUND NEBULA; R. A. 1h. 23m. 20s.; Dec. S. 7° 41' 8". Registered by Sir W. Herschel, 1785. It is just above the Whale's back.

sequence?

HISTORY.-Antiquity? Its original name? When, and why? What worship in conTELESCOPIC OBJECTS.-Beta? Gamma? Nu? Nebulæ ?

7. A ROUND STELLAR NEBULA, near & in the Whale's lower jaw, and about 2% from y on a line towards E, or south by west. A very distant object, classed by Sir W. Herschel, as 910 times as distant as stars of the first magnitude.

PERSEUS, ET CAPUT MEDUSE.-MAP III. AND IV.

58. PERSEUS is represented with a sword in his right hand, the head of Medusa in his left, and wings at his feet. It is situated directly N. of the Pleiades and the Fly, between Andromeda on the W. and Auriga on the E. Its mean declination is 46° N. It is on the meridian the 24th of December. It contains, including the head of Medusa, 59 stars, two of which are of the 2d magnitude, and four of the 3d. According to Eudosia, it contains, including the head of Medusa, 67 stars.

"Perseus next,

Brandishes high in heaven his sword of flame,
And holds triumphant the dire Gorgon's head,
Flashing with fiery snakes! the stars he counts
Are sixty-seven; and two of these he boasts,
Nobly refulgent in the second rank-

One in his vest, one in Medusa's head."

59. THE HEAD OF MEDUSA is not a separate constellation, but forms a part of Perseus. It is represented as the trunkless head of a frightful Gorgon, crowned with coiling snakes, instead of hair, which the victor Perseus holds in his hand. There are, in all, about a dozen stars in the head of Medusa; three of the 4th magnitude, and one, varying alternately from the 2d to the 4th magnitude. This remarkable star is called Algol. It is situated 12° E. of Almaack, in the foot of Andromeda, and may be known by means of three stars of the 4th magnitude, lying a few degrees S. W. of it, and forming a small triangle. It is on the meridian the 21st of December; but as it continues above the horizon 18 hours out of 24, it may be seen every evening from September to May. It varies from the 2d to the 4th magnitude in about 3 hours, and back again in the same time ; after which it remains steadily brilliant for 24 days, when the same changes recur.

The periodical variation of Algol was determined in 1783, by John Goodricke, of York (Eng.), to be 2 days, 20 hours, 49 minutes, and 56 seconds. Dr. Herschel attributes the variable appearance of Algol to spots upon its surface, and thinks it has a motion on its axis similar to that of the sun. He also observes, of variable stars generally :-" The rotary motion of the stars upon their axis is a capital feature in their resemblance to the sun. It appears to me now, that we cannot refuse to admit such a motion, and that indeed it may be as evidently proved as the diurnal motion of the earth. Dark spots,

58. Perseus? How represented? When on the meridian? 59. Head of Medusa? How represented? Number of stars? Situation? Variableness and period? When and by whom cause of variability? Lalande?

Number of stars? Size? What remarkable one? determined? Supposed

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