How do you think that the pebbles you find along the stream got there? See if you can track a pebble up the valley of the stream in which you found it. What does the river take with it as it journeys toward the sea? What part of its load drops first? _How People Know What the Cave-men Did_ Perhaps you have wondered if these stories are true. Let us see if we can find out how we got them. You know that the Cave-men lived long ago. You know that they could not read or write. You know that they did not write any stories. But they told their children the brave deeds of their people. They told them of combats with wild beasts. They told them stories about their gods. Their children told these stories again. These stories were told a great many times. Sometimes parts of the stories were left out and other parts put in. Only part of the Cave-men’s story is left, and it tells only a few things that the Cave-men did. But there are other ways of learning about them. We have learned something from the weapons that have been found. Perhaps you have done something like this yourself. Perhaps you have found an Indian arrow. Perhaps you can read what it tells of the Indians. That will help you to learn more about the Cave-men. You remember the time that the caves were flooded and the tools and weapons washed away. They were dropped on the flooded plains and buried in the sands and gravels. There have been many floods since then, and each time the river has dropped part of its load. [Illustration: _A spearhead_] So the weapons have been buried very deep. Sometimes people have dug deep down into the earth, and sometimes they have found the Cave-men’s weapons. There are pictures of some of them in this book. Can you see that they tell what the Cave-men did? Bones, too, have helped to tell something of the Cave-men. A great many bones have been found in the caves. Most of the marrow bones were split. Animals do not know how to split bones, so we know that they must have been split by men. These bones have been taken to great museums, where wise men have studied them carefully. The wise men have learned to read their story. The bones tell that the Cave-men ate animal food. They tell what animals lived at that time. They tell that people were living then, too. Perhaps you have seen fossil plants in rocks. Some of them tell what plants were living then. Many people have studied all these things. They have tried to read all the stories they tell. We have tried to learn what they have found and to write it in a story for you. Can you understand now how these stories are true? [Illustration] SUGGESTIONS TO TEACHERS