LOCATION.--A line drawn from δ Ursæ Majoris, through Polaris, strikes α Cassiopeiæ. It is situated the same distance from Polaris as Ursa Major, and about midway between Polaris and the zenith in the Milky Way. Cassiopeia is characterized by a zigzag row of stars which form a rude "W," but in mid-autumn, to an observer facing north, the "W" appears more like an "M," and is almost overhead. Note the spot marked 1572. This is where a very famous temporary star appeared in that year. It was bright enough at one time to be seen in full sunshine. The star η is sixteen light years distant. Caph is equidistant from the Pole, and exactly opposite the star Megres in Ursa Major; with α Andromedæ and γ Pegasi it marks the equinoctial colure. These stars are known as "The Three Guides." The chair can be readily traced out; β, α, and γ mark three of the four corners of the back, and δ and ε, one of the front legs. The word "Bagdei," made up of the letters for the principal stars, assists the memory. The stars γ and β are pointer stars to a fifth-magnitude star the lucida of the asterism Lacerta, the lizard about 15° from β. Cassiopeia makes an excellent illuminated clock. When β is above Polaris it is noon, when it is in the west at right angles to its first position it is 6 P.M. At midnight it is on the northern horizon, and at 6 P.M. it is due east. This is sidereal time which agrees with mean time on March 22d, and gains on the latter at the rate of two hours a month. [Illustration: CASSIOPEIA] CEPHEUS (sē´-fūs) (Face North.) LOCATION.--A line drawn from α to β Cassiopeiæ and prolonged about 18° strikes α Cephei. The nearest bright star west of Polaris is γ Cephei. Cepheus is an inconspicuous constellation, lying partly in the Milky Way. A view of this constellation through an opera-glass will repay the observer. Cepheus is characterized by a rude square, one side of which is the base of an isosceles triangle. Look for the so-called garnet star μ, probably the reddest star visible to the naked eye in the United States. The star ζ has a blue companion star. α forms an equilateral triangle with Polaris and ε Cassiopeiæ. It is claimed that Cepheus was known to the Chaldæans twenty-three centuries before our era. Surrounding δ, ε, ζ, and λ, which mark the king's head, is a vacant space in the Milky Way, similar to the Coal Sack of Cygnus. About 4° from γ, in the direction of κ is a pretty pair of sixth-magnitude stars. Owing to precession, γ, β, and α Cephei will be successively the Pole Star in 4500, 6000, and 7500 A.D. respectively. δ is a double whose components are yellow and blue. It is an interesting variable changing from magnitude 3.7 to 4.9 at intervals of 5 days 8 hours 47 minutes. As it is three times as bright at maximum as at minimum and can be observed with the naked eye its variations are well worth observing. [Illustration: CEPHEUS] PEGASUS (peg´-a-sus)--THE WINGED HORSE. (Face South.)