For a long while people were not quite so sensible about the heavenly bodies in the sky as you would be about the houses and fields seen out of a train. It seemed to them easier to believe that all the stars went round and round the earth, than to believe that the solid earth herself moved. There was this excuse, that the earth does not jar and rattle like a train, and also that the distances of the stars cannot be easily seen at a glance, like the distances of hills and valleys. We have learned differently now. We know that our earth does indeed move; and that the daily journey of the Sun, the nightly journey of the moon and planets and stars, is not a real journey. It is only a _seeming journey_. They _seem_ to move, because our earth truly moves, just as the hedges and trees _seem_ to move when looked upon out of a train which really moves. Day and night the earth moves. Day and night, year after year, she spins, like an enormous top, upon her axis. By the “axis” of the earth I mean a straight line through her centre, from the north pole to the south pole. If you have a school-globe you will see that it turns round and round upon a kind of large pin, which reaches from one pole to the other. That is its “axis,” and that is how the Earth spins. Or you may stick a long bonnet-pin through an orange, from one flattened end to the other, and spin the orange upon that pin, which is then the axis of the orange. A spinning-top also has an axis. There is no pin stuck through the top; but as it whirls round, humming, and remaining in one spot, there _is_ a line from top to bottom of it which does not seem to move. The whole top whirls round this line, which again is the axis of the top. Our Earth has no huge pin passed through her body; but, like the top, as she spins there is a line straight through her, from the north to the south pole, which keeps still, while round it whirls the whole big body of the Earth. And that is the Earth’s _axis_. If a man stands close to the north pole, or close to the south pole, at either end of the axis, he moves very little. But if he is far away from the poles, on or near the equator, the ground on which he stands rushes along at a great rate, carrying him with it. He does not feel the movement. He is not shaken or jolted. The Earth whirls very smoothly. As she spins she carries with her, on her surface, all the mountains and seas, the hills and valleys, the trees and towns and villages, yes, and the very air which we breathe. Nothing is left behind. So the man cannot know how fast he is going by any feeling of his own. He can only know it by looking up into the sky. There he sees the Sun, the Moon, the Planets, the Stars, all hurrying past. Why? Because _he_ is hurrying past--not because they are.