As we have learned, there are not only double, but triple, and also multiple stars. One of the finest ternary systems is that of [gamma] in Andromeda, above mentioned. Its large star is orange, its second green, its third blue, but the two last are in close juxtaposition, and a powerful telescope is needed to separate them. A triple star more easy to observe is [zeta] of Cancer, composed of three orbs of fifth magnitude, at a distance of 1" and 5"; the first two revolve round their common center of gravity in fifty-nine years, the third takes over three hundred years. The preceding figure shows this system in a fairly powerful objective (Fig. 18). [Illustration: FIG. 18.--Triple star [zeta] in Cancer.] In the Lyre, a little above the dazzling Vega, [epsilon] is of fourth magnitude, which seems a little elongated to the unaided eye, and can even be analyzed into two contiguous stars by very sharp sight. But on examining this attractive pair with a small glass, it is further obvious that each of these stars is double; so that they form a splendid quadruple system of two couples (Fig. 19): one of fifth and a half and sixth magnitudes, at a distance of 2.4", the other of sixth and seventh, 3.2" distant. The distance between the two pairs is 207". [Illustration: FIG. 19.--Quadruple star [epsilon] of the Lyre.] In speaking of Orion, we referred to the marvelous star [theta] situated in the no less famous Nebula, below the Belt; this star forms a dazzling sextuple system, in the very heart of the nebula (Fig. 20). How different to our Sun, sailing through Space in modest isolation! Be it noted that all these stars are animated by prodigious motions that impel them in every direction. [Illustration: FIG. 20.--Sextuple star [theta] in the Nebula of Orion.] There are no fixed stars. On every side throughout Infinity, the burning suns--enormous globes, blazing centers of light and heat--are flying at giddy speed toward an unknown goal, traversing millions of miles each day, crossing century by century such vast spaces as are inconceivable to the human intellect. If the stars appear motionless to us, it is because they are so remote, their secular movements being only manifested on the celestial sphere by imperceptible displacements. But in reality these suns are in perpetual commotion in the abysses of the Heavens, which they quicken with an extraordinary animation. These perpetual and cumulative motions must eventually modify the aspect of the Constellations: but these changes will only take effect very slowly; and for thousands and thousands of years longer the heroes and heroines of mythology will keep their respective places in the Heavens, and reign undisturbed beneath the starry vault.