A year on the Earth is about three hundred and sixty-five days long, or twelve months. Our “year” means just that time in which the Earth travels once round the Sun. And in that year, as she journeys, she turns right round upon her axis three hundred and sixty-five times. So there are two separate movements of the Earth. A boy may, if he likes, stand still, and spin round like a top. Or he may walk round the table without spinning. Or he may do the two things together: he may walk round the table, and as he goes he may keep spinning like a top. That is how the Earth goes round the Sun. As she moves she is always at much the same distance from the Sun--about 92 millions of miles off. In one part of her pathway she is a little farther, and in another part a little nearer; but there is never very much difference. Sometimes she is on one side of the Sun, sometimes on another side. Always, day after day, and year after year, she keeps steadily journeying round and round the Sun. This is how we get our seasons upon Earth. Spring is followed by summer, summer by autumn, autumn by winter, winter by spring again. It is on and on, the same thing, year after year. In an earlier chapter you heard about the Equinoxes and the Solstices. There is an Equinox in the spring, a Solstice in the summer, an Equinox in the autumn, and a Solstice in the winter. At each of these times the Earth is in a different part of her pathway round the Sun. Also she is differently _placed_. It is of course quite clear to you by this time that our Earth is a round solid globe in the sky. Also that the axis of the Earth is a straight line from her north to her south pole, right through the middle of her. Now I want you to understand that, as the Earth goes round the Sun, her axis _leans over a_ _little_ in one direction, and always in the same direction. Have you a good-sized soft ball to picture the Earth? Stick a big bonnet-pin right through the middle of it; that pin is the Earth’s axis. The pin’s head shows the north pole, and the pin’s point shows the south pole. Properly, of course, if this little Earth is about four inches through in size, it ought to travel round and round a huge shining balloon, three-quarters of a mile off, to show how the Earth goes round the Sun. But this, I am afraid, you will hardly be able to manage. So you must let distances alone, and just have a candle or a lamp on a table, and learn with that how we get our summer and winter. First, now, hold the ball on one side of the candle. Let its north pole--the pin’s head--point in a sloping way _over_ the candle-flame; not exactly towards the candle, and not up straight towards the ceiling, but in a slant.