We look first, as in former cases, for the Great Bear, now lying low down towards the north. Towards the north-east, a few degrees easterly, are the twin-stars Castor and Pollux, in a vertical position, Castor uppermost. Above these, a little towards the right, we see the brilliant Capella; and between Capella and the zenith is seen the festoon of Perseus. Cassiopeia lies near the zenith, towards the north, and the Milky Way extends from the eastern horizon across the zenith to the western horizon. Low down in the east is Orion, half risen above horizon. Turning to the south, we see high up above the horizon the square of Pegasus. Low down towards the south-south-west is Fomalhaut, pointed to by [beta] and [alpha] Pegasi. Towards the west, about half-way between the zenith and the horizon, is the noble cross in Cygnus; below which, towards the left, we see Altair, and his companions [beta] and [gamma] Aquilae: while towards the right we see the brilliant Vega. During this half-hour we shall not confine ourselves to any particular region of the heavens, but sweep the most conveniently situated constellations. [Illustration: PLATE V.] First, however, we should recommend the observer to try and get a good view of the great nebula in Andromeda, which is _not_ conveniently situated for observation, but is so high that after a little trouble the observer may expect a more distinct view than in the previous quarter. He will see [beta] Andromedae towards the south-east, about 18 deg. from the zenith, [mu] and [nu] nearly in a line towards the zenith, and the nebula about half-way between [beta] and the zenith. With a similar object it will be well to take another view of the great cluster in Perseus, about 18 deg. from the zenith towards the east-north-east (_see_ the pointers [gamma] and [delta] Cassiopeiae in Map 4, Frontispiece), the cluster being between [delta] Cassiopeiae and [alpha] Persei. Not very far off is the wonderful variable Algol, now due east, and about 58 deg. above the horizon. The variability of this celebrated object was doubtless discovered in very ancient times, since the name Al-gol, or "the Demon" seems to point to a knowledge of the peculiarity of this "slowly winking eye." To Goodricke, however, is due the rediscovery of Algol's variability. The period of variation is 2d. 20h. 48m.; during 2h. 14m. Algol appears of the second magnitude; the remaining 6-3/4 hours are occupied by the gradual decline of the star to the fourth magnitude, and its equally gradual return to the second. It will be found easy to watch the variations of this singular object, though, of course, many of the minima are attained in the daytime. The following may help the observer:--