The “Plow,” or Great Bear,[16] is familiar to most people. This remarkable group of seven stars will be found very useful in identifying some of the brighter stars. The two stars furthest from the “tail” are called “pointers,” as they point nearly to the Pole Star, or star to which the axis of the earth nearly points. I say “nearly,” for the Pole Star is not _exactly_ at the pole, but distant from it about three diameters of the moon. The northern of these stars is known to astronomers by the Greek letter Alpha and the southern as Beta. The others, following the order of the figure, are known by the letters Gamma, Delta (the faintest of the seven), Epsilon, Zeta, and Eta.[17] Now, if the curve formed by the three stars in the tail, Epsilon, Zeta, and Eta, is continued on, it will pass near a very bright star. This is Arcturus (Alpha of the constellation Boötes), one of the brightest stars visible. Again, if we draw an imaginary line from Gamma to Beta, and produce it, it will pass near another bright star. This is Capella (Alpha of Auriga, “the Charioteer” referred to by Tennyson). Again, if we draw a line from Delta to Beta, and produce it, it will pass near the tolerably bright stars, Castor and Pollux (Alpha and Beta of the constellation Gemini, or the Twins), the northern of the two being Castor. Another line from Delta to Gamma produced will pass near a bright star called Regulus (Alpha of Leo, the Lion). Another line from Beta to Eta will pass near a group called Corona Borealis, or the Northern Crown. [Illustration: Constellation of Orion, showing the Belt and Sword] On the opposite side of the Pole Star from the Plow, a group of five conspicuous stars will be found, forming a figure shaped somewhat like a W. This is Cassiopeia’s Chair. Commencing with the most westerly of the five, these stars are known as Beta, Alpha, Gamma, Delta, and Eta. Like the stars of the Plow, those of Cassiopeia’s Chair may be used to find other stars. For instance, a line drawn from Beta to Alpha passes close to a star known as Gamma in Andromeda; and the same line produced in the opposite direction will pass a little north of the bright star Vega (Alpha Lyræ), one of the brightest stars in the northern heavens. A line from Gamma to Alpha produced will pass through the well-known “Square of Pegasus.” To the east of Vega lies Cygnus, or the Swan, a well-known northern constellation. It may be recognized by the long cross formed by its principal stars, Alpha, Beta, Gamma, Delta, and Epsilon; Alpha, or Deneb, being the most northern and brightest, and Beta the most southern and faintest of the five.