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earlier, or at 9 minutes to 11. In three months the culmination takes place 6 hours earlier, or at 5 minutes to 5. In six months, i.e. on Sept. 22, it culminates at 10.55 in the morning, being vertically below the pole at the same hour in the evening. The following woodcut exhibits the positions of the Great Bear at the various hours of September 4th. It is plain from this that, knowing the day of the month, the hour of the night may be told by observing what angle the line joining α and β of this constellation makes with the vertical.

      We have used the name Great Bear, by which the constellation is best known. It is one of the oldest names also, being derived from the Greeks, who called it Arctos megale (Ἄρκτος μεγάλη), whence the name Arctic; and singularly enough the Iroquois, when America was discovered, called it Okouari, their name for a bear. The explanation of this name is certainly not to be found in

      Fig. 4. Fig. 4.

      the resemblance of the constellation to the animal. The three stars are indeed in the tail, but the four are in the middle of the back; and even if we take in the smaller stars that stand in the feet and head, no ingenuity can make it in this or any other way resemble a bear. It would appear, as Aristotle observes, that the name is derived from the fact, that of all known animals the bear was thought to be the only one that dared to venture into the frozen regions of the north and tempt the solitude and cold.

      Fig. 5. Fig. 5.

      Other origins of the name, and other names, have been suggested, of which we may mention a few. For example, "Ursa" is said to be derived from versus, because the constellation is seen to turn about the pole. It has been called the Screw (Ἔλικη), or Helix, which has plainly reference to its turning. Another name is Callisto, in reference to its beauty; and lastly, among the Arabs the Great and Little Bears were known as the Great and Little Coffins in reference to their slow and solemn motion. These names referred to the four stars of each constellation, the other three being the mourners following the bearers. The Christian Arabs made it into the grave of Lazarus and the three weepers, Mary, Martha, and their maid.

      Next as to the Little Bear. This constellation has evidently received its name from the similarity of its form to that of the Great Bear. In fact, it is composed of seven stars arranged in the same way, only in an inverse order. If we follow the line from β to α of the Great Bear to a distance of five times as great as that between these stars we reach the brightest star of the Little Bear, called the Pole Star. All the names of the one constellation have been applied to the other, only at a later date.

      The new constellations were added one by one to the celestial sphere by the Greeks before they arranged certain of them as parts of the zodiac. The successive introduction of the constellations is proved completely by a long passage of Strabo, which has been often misunderstood. "It is wrong," he says, "to accuse Homer of ignorance because he speaks only of one of the two Celestial Bears. The second was probably not formed at that time. The Phenicians were the first to form them and to use them for navigation. They came later to the Greeks."

      All the commentators on Homer, Hygin and Diogenes Laertes, attribute to Thales the introduction of this constellation. Pseudo-Eratosthenes called the Little Bear Φοινίκη, to indicate that it was a guide to the Phenicians. A century later, about the seventeenth Olympiad, Cleostrates of Tenedos enriched the sphere with the Archer (Τοξότης, Sagittarius) and the Ram (Κριός, Aries), and about the same time the zodiac was introduced into the Grecian sphere.

      The Constellations from the Sea-Shore. The Constellations from the Sea-Shore.

      The Swan—The Lyre—Hercules—The Crown—The Herdsman—The Eagle—The Serpent—The Balance—The Scorpion—Sagittarius.

      With regard to the Little Bear there is another passage of Strabo which it will be interesting to quote. He says—"The position of the people under the parallel of Cinnamomophore, i.e. 3,000 stadia south of Meroe and 8,800 stadia north of the equator, represents about the middle of the interval between the equator and the tropic, which passes by Syene, which is 5,000 stadia north of Meroe. These same people are the first for whom the Little Bear is comprised entirely in the Arctic circle and remains always visible; the most southern star of the constellation, the brilliant one that ends the tail being placed on the circumference of the Arctic circle, so as just to touch the horizon." The remarkable thing in this passage is that it refers to an epoch anterior to Strabo, when the star α of the Little Bear, which now appears almost immovable, owing to its extreme proximity to the pole, was then more to the south than the other stars of the constellation, and moved in the Arctic circle so as to touch the horizon of places of certain latitudes, and to set for latitudes nearer the equator.

      In those days it was not the Pole Star—if that word has any relation to πολέω, I turn—for the heavens did not turn about it then as they do now.

      The Grecian geographer speaks in this passage of a period when the most brilliant star in the neighbourhood of the pole was α of the Dragon. This was more than three thousand years ago. At that time the Little Bear was nearer to the pole than what we now call the Polar Star, for this latter was "the most southern star in the constellation." If we could alight upon documents dating back fourteen thousand years, we should find the star Vega (α Lyra) referred to as occupying the pole of the world, although it now is at a distance of 51 degrees from it, the whole cycle of changes occupying a period of about twenty-six thousand years.

      Before leaving these two constellations we may notice the origin of the names according to Plutarch. He would have it that the names are derived from the use that they were put to in navigation. He says that the Phenicians called that constellation that guided them in their route the Dobebe, or Doube, that is, the speaking constellation, and that this same word happens to mean also in that language a bear; and so the name was confounded. Certainly there is still a word dubbeh in Arabic having this signification.

      Next as to the Herdsman. The name of its characteristic star and of itself, Arcturus (Ἄρκτος, bear; Οὖρος, guardian), is explained without difficulty by its position near the Bears. There are six small stars of the third magnitude in the constellation round its chief one—three of its stars forming an equilateral triangle. Arcturus is in the continuation of the curved line through the three tail stars of the Great Bear. The constellation has also been called Atlas, from its nearness to the pole—as if it held up the heavens, as the fable goes.

      Beyond this triangle, in the direction of the line continued straight from the Great Bear, is the Northern Crown, whose form immediately suggests its name. Among the stars that compose it one, of the second magnitude, is called the Pearl of the Crown. It was in this point of the heavens that a temporary star appeared in May, 1866, and disappeared again in the course of a few weeks.

      Among the circumpolar constellations we must now speak of Cassiopeia, or the Chair—or Throne—which is situated on the opposite side of the Pole from the Great Bear; and which is easily found by joining its star δ to the Pole and continuing it. The Chair is composed principally of five stars, of the third magnitude, arranged in the form of an M. A smaller star of the fourth magnitude completes the square formed by the three β, α, and γ. The figure thus formed has a fair resemblance to a chair or throne, δ and ε forming the back; and hence the justification for its popular name. The other name Cassiopeia has its connection and meaning unknown.

      We may suitably remark in this place, with Arago, that no precise drawing of the ancient constellations has come down to us. We only know their forms by written descriptions, and these often very short and meagre. A verbal description can never take the place of a drawing, especially if it is a complex figure, so that there is a certain amount of doubt as to the true form, position, and arrangement of the figures of men, beasts, and inanimate objects which composed the star-groups of the Grecian astronomers—so that unexpected difficulties attend the attempt to reproduce them on our modern spheres. Add to this that alterations have been avowedly

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