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liant star a Lyre will fulfil the office of polar star

for those who shall then live on the earth.

Curious fact concerning the Pyramids. Of the nine Pyramids which are standing at Gizeh, Egypt, six have openings facing the north. These lead to straight passages which descend at a uniform angle of about 26° and are parallel with the meridian. If we suppose a person, 4000 years ago, standing at the lower end of one of these passages, and looking out, his eye would strike the sky near the star Thuban, which was then the polar star. The supposed date of the building of these Pyramids (2123 B. C.) agrees with that epoch, and very naturally suggests that the builders had some special design in this peculiar construction.

The distance of Polaris is so great, that though the star is moving through space at the rate of ninety miles per minute, this tremendous speed is imperceptible to us. It requires nearly fifty years for its light to reach the earth; so that when we look at Polaris, we know that the ray which strikes our eye set out on its journey through space half a century ago. We cannot state positively that the star is now in existence, since if it were destroyed to-day it would be fifty years before we should miss it.

Calculation of latitude from Polaris.-By an observer at the equator, Polaris is seen at the horizon. If he advances north, the horizon is depressed and Polaris seems to rise in the heavens. When it has reached the height of a degree, the ob

server is said to have passed over a degree of latitude on the earth's surface. As he moves further north, the polar star continues to ascend; its distance above the horizon denoting the latitude of each place in succession, until at the north pole, if one could reach that point, Polaris would be seen directly overhead.

Draco is represented under the figure of a long sinuous serpent, stretching between Ursa Major and Ursa Minor, nearly encircling the latter constellation, and finally reaching out its head almost to the body of Hercules.

Principal stars.-Four small stars form a quadrilateral figure at the head; a fifth of the fourth magnitude which is scarcely visible, marks the end of the nose; several scattered groups and delicate triangles of small stars, denote the position of the various coils of the body; thence, an irregular line of stars traces the dragon's tail around between Ursa Major and Ursa Minor. Thuban lying midway between y of the Little Dipper and of the Big Dipper, is noted as the polar star of forty centuries ago.

Mythological history.-Many accounts are given of the origin of this constellation, as indeed there are of almost every one in the heavens. The prevalent opinion is, that it is the dragon which Cadmus slew. The story is as follows. Jupiter had carried off Európa. Agénor, her father, sent her brother Cadmus in pursuit of his lost sister, bidding him not to return until he was successful in his search. After a

to build a city.

time, Cadmus, weary of his wanderings, inquired of the oracle of Apollo concerning the fate of Europa. He was told to cease looking for his sister, to follow a cow as a guide, and when she rested, there Hardly had Cadmus stepped out of the temple, when he saw a cow slowly walking along. He followed her until she came upon the broad plains where Thebes afterward stood. Here she stopped. Cadmus wishing to offer a sacrifice to Jupiter in gratitude for the delightful location, sent his servants to seek for water. In a dense grove near by was a fountain guarded by a fierce dragon (DRACO), and sacred to Mars. The Tyrians approaching this and attempting to dip up some water, were attacked, and many of them killed by that enormous serpent, whose head overtopped the tallest trees. Cadmus, becoming impatient, went in search of his men, and on coming to the spring, saw the sad disaster. He forthwith fell upon the monster, and after a severe battle succeeded in slaying him. While standing over his conquered foe, he heard a voice from the ground bidding him take the dragon's teeth and sow them. He obeyed. Scarcely had he finished ere the earth began to move and the points of spears to prick through the surface. Next nodding plumes shook off the clods, and the heads of armed men protruded. Soon a great harvest of warriors covered the entire plain. Cadmus, in terror at the appearance of these giants, whom he termed Sparti (the Sown), prepared to attack them, when suddenly they

turned upon themselves, and never ceased their warfare until only five of the crowd survived. These making peace with each other, joined Cadmus and assisted him in building the city of Thebes.

Cepheus is represented as a king in regal state, with a crown of stars on his head, while he holds in his hand a sceptre which is extended toward his wife, Cassiopeia. The constellation contains thirtyfive stars visible to the naked eye

Principal stars.-The brightest star is Alderamin (a), in the right shoulder. Alphirk (6), in the girdle, is at the common vertex of several triangles, which point out respectively the left shoulder (), the left knee (7), and the right foot. The head, which lies in the Milky Way, is marked by a delicate little triangle of three stars. This forms, with a, ß, and ‹, quite a regular quadrilateral figure. A bright little star of the fifth magnitude, close to Polaris, points out the left foot.

Cassiopeia* is represented as a queen seated on her throne. On her right is the king, on her left Perseus, her son-in-law, and above her is Andromeda, her daughter. The constellation contains fiftyfive stars visible to the naked eye.

Principal stars.-A line drawn from Megrez (5), in Ursa Major, through Polaris and continued an equal distance beyond, will strike Caph (6) in Cassiopeia. This star is noticeable as marking, with the others

* For mythological history, see Perseus and Andromeda.

named, the equinoctial colure, and as being on the same side of the true pole as Polaris. The principal stars form the figure of an inverted chair, which is very striking and may be easily traced.

EQUATORIAL CONSTELLATIONS.

The constellations we shall now describe lie south of the circumpolar groups. Only a portion of their paths is above our horizon. In using the maps, the observer is supposed to stand with his back toward Polaris, and to be looking directly south. Commencing with the constellation Perseus, so intimately connected with the other members of the royal family just described, we pass eastward in our survey and notice the various constellations as they slowly defile in silent march across the sky. The first map represents the constellations on or near the meridian at nine o'clock in the evening of the winter solstice. On the evening of the autumnal equinox, the lefthand side of the map should be turned downward toward the eastern horizon. On the evening of the vernal equinox, the right-hand side should be turned to the western horizon. At these different times, the stars, though preserving their relative positions, will be diversely inclined to the horizon. As the stars apparently move westward at the rate of 15° per hour, the time of the evening determines what stars will be visible, and also their distances above the horizon,

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