World Leaders Biography

The First Living Things We saw in our last letter that for a long time the earth must have been too hot for any living things to exist on it. When did life begin on the earth and what were the first living things? That is a very interesting question but it is also a very difficult question to answer. Let us first consider what life is. You will probably say that men are living beings and so are all animals. What about trees and shrubs and flowers and vegetables? Surely they are living also. They grow and drink up the water and breathe the air and die. The chief difference between a tree and an animal is that the tree does not move about. If you remember, I showed you some plants in Kew Gardens in London. These plants--orchids and pitcher plants--actually eat flies. Then there are some animals, like sponges, which live at the bottom of the sea and do not move about. Sometimes it is very difficult to say whether a thing is an animal or a plant. When you study botany, the science whi...

You know that the earth goes round the sun and the moon goes round the earth. You know also perhaps that there are several other bodies which, like the earth, go round the sun. All these, including our earth, are called planets of the sun. The moon is called a satellite of the earth because it hangs on to it. The other planets have also got their satellites. The sun and the planets with their satellites form a happy family. This is called the solar system. Solar means belonging to the sun, and the sun being the father of all the planets the whole group is called the solar system. At night, you see thousands of stars in the sky. Only a few of these are the planets and these are really not called stars at all. Can you distinguish between a planet and a star? The planets are really quite tiny, like our earth, compared to the stars but they look bigger in the sky because they are much nearer to us. Just as the moon, which is really quite a baby, looks so big because it is quite near ...