Where the sun and his planets will journey in future ages no living man can say. Indeed, though it is a question which does not lack interest to a thoughtful mind, yet there are numberless other questions about centuries near at hand which concern man far more nearly. The history of the Universe, and the history of this Earth of ours, must have advanced many broad stages before our sun and his attendant planets can have traveled so far that any change will be apparent in the shape of the star-constellations which spangle our sky. CHAPTER XI. MORE ABOUT THE SOLAR SYSTEM. We have now reached a point where it ought not to be difficult for us to picture to ourselves, with something of vividness, the general outlines of the Solar System. Awhile ago this Solar System was a very simple matter in the eyes of astronomers. There was the great sun fixed in the center, with seven planets circling round him--seven of course, it was said, since seven was the perfect number--and a few moons keeping pace with some of the planets, and an occasional comet, and a vast amount of black, empty space. But astronomers now begin to understand better the wonderful richness of the system as a whole; the immense variety of the bodies contained in it; the perpetual rush and stir and whirl of life in every part. Certainly there is no such thing as dull stagnation throughout the family. First, we have the great, blazing, central sun; not a sun at rest, as regards the stars, but practically at rest as regards his own system, of which he is always head and center. Then come the four smaller planets, rapidly whirling round him, all journeying in the same direction, and all having their oval pathways lying on nearly the same flat plane in space. Then the broad belt of busy little planetoids. Then the four giant planets,--Jupiter nearly five times as far as our earth from the sun; Saturn nearly twice as far as Jupiter; Uranus nearly twice as far as Saturn; Neptune as far from Uranus as Uranus from Saturn,--all keeping on very nearly the same level as the four inner planets. [Illustration: POSITION OF PLANETS INFERIOR TO JUPITER--SHOWING THE ZONE OF THE ASTEROIDS.] And between and about these principal members of the system, with their accompanying moons, we have thousands of comets flashing hither and thither, with long, radiant trains; and myriads of meteorites, gathered often into dense, vast herds or families, but also scattered thickly throughout every part of the system, each tiny ball reflecting the sun’s rays with its little glimmer of light.