Each little meteor that journeys round the Sun shined, like the worlds, on one side only--that side which is towards the Sun. QUESTIONS. 1. What are Meteors? The smallest heavenly bodies known to us. 2. How many meteors are there? Immense multitudes in the sky, beyond our power even to imagine. 3. How do meteors shine when journeying in the sky? They shine by borrowed sunlight. 4. Does a meteor shine all round? No; only on that side which is towards the Sun. 5. Do we see meteors by means of that borrowed sunlight? No; we only see them when they rush into our air. 6. What makes them visible to us then? They are so much heated by the rubbing of the air as to shine brightly for a moment with their own light. 7. What becomes of such meteors? The outside is melted and streams behind as shining dust. 8. Does any part of them reach the ground? Generally they are destroyed in their rush through the air, and only the dust drops downwards. 9. Are they always quite destroyed? Sometimes a part escapes, if the meteor is rather large, and then a solid lump of rock or metal comes to the ground. 10. What is such a lump called? A Meteorite, or an Aerolite, or a Meteoric Stone. 11. What is it really? Part of a meteor from the sky. 12. What do we call a meteor seen only by its last flash? Either a “meteor” or “a shooting star.” 13. When are shooting-stars most common? In August and November. 14. Why? Because our Earth then touches meteor rings, and so a great many come into our air. 15. When does our Earth plunge deep into a meteor-ring? About once in every thirty-three years. 16. What is seen then? A most wonderful display of tens of thousands of meteors. CHAPTER XIX. THE SUN’S KINGDOM. By this time you have a pretty fair idea of what is meant by “The Solar System.” First you had to think about our Earth’s pathway in the sky, and then about other pathways, nearer and farther, like vast oval hoops lying within and without the Earth’s pathways. Lying, all of them, very nearly on the same level. But the Planetoids’ paths do not keep at all nearly to that level, rings of Meteors slope about in different ways, and Comets come and go, with no known rule, from any part of the heavens. When we talk of a “level” in the sky--a “plane” is the better word--you must not think of a solid flat surface any more than you have to picture real pathways for the planets. No signposts mark the pathways, and the level or plane cannot be _seen_, except by the way in which the worlds journey. How far the Solar System reaches, and where it stops, I cannot tell you. The Sun’s power goes out beyond his own kingdom: for the distant Stars feel his pull. Only that gentle pull is very much weaker than the strong hold which he has over all his own worlds. Neptune is the most distant world known to us; and Neptune, as you have heard, is some 2,800 millions of miles away from the Sun.