LITMIR.BIZ

      Thus ♈ refers to the horns of the Ram; ♉ to the head of the Bull; ♏ to the joints and tail-sting of the Scorpion; ♐ is very clearly connected with an archer; ♑ is formed by the junction of the first two letters τ and ρ in τράγος, the Sea-goat, or Capricorn; ♎ for the Balance, is suggestive of its shape; ♒ refers to the water in the Watering-pot; and perhaps ♓ to the Two Fishes; ♊ for Twins may denote two sides alike; ♋ for the Crab, has something of its side-walking appearance; while ♌ for the Lion, and ♍ for the Virgin, seem to have no reference that is traceable.

      These constellations contain the following stars of the first magnitude—Aldebaran, Antares, and Spica.

      To these constellations admitted by the Greeks should be added the Locks of Berenice, although it is not named by Ptolemy. It was invented indeed by the astronomer Conon. The story is that Berenice was the spouse and the sister of Ptolemy Euergetes, and that she made a vow to cut off her locks and devote them to Venus if her husband returned victorious; to console the king the astronomer placed her locks among the stars. If this is a true account Arago must be mistaken in asserting that the constellation was created by Tycho Brahe in 1603. The one he did add to the former ones was that of Antinöus, by collecting into one figure some unappropriated stars near the Eagle. At about the same time J. Bayer, from the information of Vespuccius and the sailors, added twelve to the southern constellations of Ptolemy; among which may be mentioned the Peacock, the Toucan, the Phœnix, the Crane, the Fly, the Chameleon, the Bird of Paradise, the Southern Triangle, and the Indian.

      Augustus Royer, in 1679, formed five new groups, among which we may name the Great Cloud, the Fleur-de-Lis, and the Southern Cross.

      Hevelius, in 1690, added 16; the most important being the Giraffe, the Unicorn, the Little Lion, the Lynx, the Little Triangle.

      Among these newer-named constellations none is more interesting than the Southern Cross, which is by some considered as the most brilliant of all that are known. Some account of it, possibly from the Arabs, seems to have reached Dante, who evidently refers to it, before it had been named by Royer, in a celebrated passage in his "Purgatory." Some have thought that his reference to such stars was only accidental, and that he really referred only to the four cardinal virtues of theology, chiefly on account of the difficulty of knowing how he could have heard of them; but as the Arabs had establishments along the entire coast of Africa, there is no difficulty in understanding how the information might reach Italy.

      Americus Vespuccius, who in his third voyage refers to these verses of Dante, does not mention the name of the Southern Cross. He simply says that the four stars form a rhomboidal figure. As voyages round the Cape multiplied, however, the constellation became rapidly more celebrated, and it is mentioned as forming a brilliant cross by the Florentine Andrea Corsali, in 1517, and a little later by Pigafetta, in 1520.

      All these constellations have not been considered sufficient, and many subsequent additions have been made. Thus Lacaille, in 1752, created fourteen new ones, mostly characterized by modern names—as the Sculptor's Studio, the Chemical Furnace, the Clock, the Compass, the Telescope, the Microscope, and others.

      Lemonnier, in 1766, added the Reindeer, the Solitaire, and the Indian Bird, and Lalande the Harvestman. Poczobut, in 1777, added one more, and P. Hell another. Finally, in the charts drawn by Bode, eight more appear, among which the Aerostat, and the Electrical and Printing Machines.

      We thus arrive at a total of 108 constellations. To which we may add that the following groups are generally recognized. The Head of Medusa, near Perseus; the Pleiades, on the back, and the Hyades on the forehead of the Bull; the Club of Hercules; the Shield of Orion, sometimes called the Rake; the Three Kings; the Staff of S. James; the Sword of Orion; the Two Asses in the Crab, having between them the Star Cluster, called the Stall, or the Manger; and the Kids, near Capella, in the constellation of the Coachman.

      This brings the list of the constellations to 117, which is the total number now admitted.

      A curious episode with respect to these star arrangements may here be mentioned.

      About the eighth century Bede and certain other theologians and astronomers wished to depose the Olympian gods. They proposed, therefore, to change the names and arrangements of the constellations; they put S. Peter in the place of the Ram; S. Andrew instead of the Bull; and so on. In more recent calendars David, Solomon, the Magi, and other New and Old Testament characters were placed in the heavens instead of the former constellations; but these changes of name were not generally adopted.

      As an example of these celestial spheres we figure a portion of one named Cœli stellati Christiani hemisphericum prius. We here see the Great Bear replaced by the Barque of S. Peter, the Little Bear by S. Michael, the Dragon by the Innocents, the Coachman by S. Jerome, Perseus by S. Paul, Cassiopeia by the Magdalene, Andromache by S. Sepulchre, and the Triangle by S. Peter's mitre; while for the zodiac were substituted the Twelve Apostles.

       Fig. 3.

      In the seventeenth century a proposal was made by Weigel, a professor in the University of Jena, to form a series of heraldic constellations, and to use for the zodiac the arms of the twelve most illustrious families in Europe; but these attempts at change have been in vain, the old names are still kept.

      Having now explained the origin in modern times of 69 out of the 117 constellations, there remain the 48 which were acknowledged by the Greeks, whose origin is involved in more obscurity.

      One of the first to be noticed and named, as it is now the most easily recognized and most widely known, is the Great Bear, which attracts all the more attention that it is one of those that never sets, being at a less distance from the pole than the latter is from the horizon.

      Every one knows the seven brilliant stars that form this constellation. The four in the rectangle and the three in a curved line at once call to mind the form of a chariot, especially one of antique build. It is this resemblance, no doubt, that has obtained for the constellation the name of "the Chariot" that it bears among many people. Among the ancient Gauls it was "Arthur's Chariot." In France it is "David's Chariot," and in England it goes by the name of "King Charles' Wain," and by that of the "Plough." The latter name was in vogue, too, among the Latins (Plaustrum), and the three stars were three oxen, from whence it would appear that they extended the idea to all the seven stars, and at last called them the seven oxen, septem-triones, from whence the name sometimes used for the north—septentrional. The Greeks also called it the Chariot (Ἅμαξα), and the same word seems to have stood sometimes for a plough. It certainly has some resemblance to this instrument.

      If we take the seven stars as representing the characteristic points of a chariot, the four stars of the quadrilateral will represent the four wheels, and the three others will represent the three horses. Above the centre of the three horses any one with clear sight may perceive a small star of the fifth or sixth magnitude, called the Cavalier. Each of these several stars is indicated, as is usual with all the constellations, by a Greek letter, the largest being denoted by the first letter. Thus the 4 stars in the quadrilateral are α, β, γ, δ, and the 3 tail stars ε, ξ, η. The Arabs give to each star its special name, which in this case are as follows:—Dubhé and Mérak are the stars at the back; Phegda and Megrez those of the front; Alioth, Mizat, and Ackïar the other three, while the little one over Mizat is Alcor. Another name for it is Saidak, or the Tester, the being able to see it being a mark of clear vision.

      There is some little interest in the Great Bear on account of the possibility of its being used as a kind of celestial time-keeper, and its easy recognition makes it all the more available. The line through α and β passes almost exactly through the pole. Now this line revolves of course with the constellation round the pole in 24 hours; in every such interval being once, vertical above the pole, and once vertical below, taking the intermediate positions to right and left between these times. The instant at which this line is vertical over the pole is not the same on any two consecutive nights, since the stars advance each day 4 minutes on the sun. On the 21st of

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