17 CHAPTER THE SECOND. TWILIGHT.-ROTATION OF THE EARTH ON ITS AXIS. FORM OF THE SUN.-ROTATION OF THE SUN ON ITS AXIS. FIXED STARS.PLANETS.MILKY WAY.-CONSTELLATIONS. -HUMBOLDT. ELIZABETH. THE morning is delightful; but I did not expect that it would have been so dark, so near the break of day. MOTHER. In winter the Twilight, or the imperfect light that we have before sunrise, and after sunset, is very short. This is now in our favour, for in summer, at this hour of the morning, the sun's light would prevent our seeing the stars, for the same reason that it seems to obscure the light of the fire, or of a candle during the day. We shall very soon perceive the starlight fading away as daybreak comes on. Now, William, tell me, whether you recollect any of your acquaintance among the stars? WILLIAM. I cannot find Venus. ELIZABETH. Because she has long since gone down; you remember that when we saw her last night, she was very near setting. Even Jupiter, that was so high last night, is now very low. WILLIAM. What a great part of the sky he has gone over! MOTHER. But can you see nothing more? so bright behind the trees? What is that WILLIAM. Oh! it is the Moon; how very thin and sharp the points are. MOTHER. She is now in the last quarter, and she will very soon be so near the sun, that we shall see no more of her for a few days. You perceive that her points, which are called the Horns, the moon when she has that shape being called a Crescent, are turned towards the west, and this you must not forget. You see then, that since last night, Jupiter and all the other stars seem to have moved, nearly from east to west in the sky. Venus has wholly disappeared, and the sun which we saw yesterday evening going down in the west, will very soon appear again in the east; so that either all the stars, with the sun and moon, must have moved half round the earth, or which would produce exactly the same appearances, the earth itself must have revolved half way round. Which do you think has happened? ELIZABETH. It seems more probable that the earth should have revolved, than that so many different bodies should move together round it. MOTHER. The earth does revolve on its own axis; and we shall find a new proof of this by looking towards the Pole. William, where is the Great Bear? WILLIAM. I have been looking for it for some time, but it seems to have gone out of its place, and to be much lower in the sky: it is below the Pole Star, and its tail is turned quite a different way. ELIZABETH.. Yet the Pole Star is just where it was, directly over the cottage chimney. You would not suppose then that all these stars remain exactly as they were last night, and that we ourselves have changed our position so much that our heads point to an entirely different part of the heavens. Let us go in and look at your orange and wire. Now, suppose that we were standing upon the orange, as this little figure [see Plate 3.] is, when turned to A, upon the drawing of a globe; your orange may be turned round you perceive, without altering the direction of the |