Astronomers, those people who study the starts, tell us that long-long ago the earth and all the planets were part of the sun. The sun was then as it is now a mass of flaming matter, terribly hot. Somehow little bits of the sun got loose and they shot out into the air. But they could not wholly get rid of their father, the sun. It was as if a rope was tied to them and they kept whirling round the sun. This strange force, which I have compared to a rope, is something which attracts little things to great. It is the force which makes things fall by their weight. The earth being the biggest thing near us, attracts everything we have. In this way our earth also shot us from the sun. It must have been very hot. With terrible hot gases and air all around it, but as it was very much smaller than the sun, it started to cool. The sun also is getting less hot but is will take millions of years to cool down. The earth took much less time to cool. When it was hot, of course nothing could live on it-no man or animal or plant or tree. Everything would have been burnt up then. Just as a bit of the sun shot out and became the moon. Many people think that the moon came out and of the great hollow which is now the Pacific Ocean, between America and Japan. So, the earth started to cool. It took a long time over it. Gradually the surface of the earth became cooler although the interior remained very hot. Even how if you go down. Probably if you could go down deep enough inside the earth you would find it red hot. The moon also started to cool and because it was much smaller than even the earth is cooled more quickly than the earth. It looks delightfully cool, dies it not? It is called the "cold moon". Perhaps it is full of glaciers and ice fields. When the earth cooled all the water vapour in the air condensed into water and probably came down as rain. It must have rained a tremendous lot then. All this water filled the great hollows in the earth and so the great oceans and seas were formed. As the earth became cooler and the oceans also became cooler, it became possible for living things to exist on the earth's surface or in the sea.