Between the Great and the Little Bear, we can distinguish a winding procession of smaller stars. These constitute the Dragon.
We will continue our journey by way of Cassiopeia, a fine constellation placed on the opposite side of the Pole-Star in relation to the Great Bear, and shaped somewhat like the open limbs of the letter W. It is also called the Chair. And, in fact, when the figure is represented with the line [alpha] [beta] below, the line [chi] [gamma] forms the seat, and [gamma] [delta] [epsilon] its back.
If a straight line is drawn from [delta] of the Great Bear, and prolonged beyond the Pole-Star in a quantity equal to the distance which separates these two stars, it is easy to find this constellation (Fig. 5). This group, like the preceding, never sets, and is always visible, opposite to the Great Bear. It revolves in twenty-four hours round the Pole-Star, and is to be seen, now above, now below, now to the right, now to the left.
[Illustration: FIG. 5.--To find Cassiopeia.]
[Illustration: FIG. 6.--To Find Pegasus and Andromeda.]
If in the next place, starting from the stars [alpha] and [delta] in the Great Bear, we draw two lines which join at Polaris and are prolonged beyond Cassiopeia, we arrive at the Square of Pegasus (Fig. 6), a vast constellation that terminates on one side in a prolongation formed of three stars.
These three last stars belong to Andromeda, and themselves abut on Perseus. The last star in the Square of Pegasus is also the first in Andromeda.
[gamma] of Andromeda is a magnificent double orb, to which we shall return in the next chapter, _i.e._, the telescope resolves it into two marvelous suns, one of which is topaz-yellow, and the other emerald-green. Three stars, indeed, are visible with more powerful instruments.
[Illustration: FIG. 7.--Perseus, the Pleiades, Capella.]
Above [beta] and near a small star, is visible a faint, whitish, luminous trail: this is the oblong nebula of Andromeda, the first mentioned in the history of astronomy, and one of the most beautiful in the Heavens, perceptible to the unaided eye on very clear nights.
The stars [alpha], [beta] and [gamma] of Perseus form a concave bow which will serve in a new orientation. If it is prolonged in the direction of [delta], we find a very brilliant star of the first magnitude. This is Capella, the Goat, in the constellation of the Charioteer (Fig. 7).