was dragged into the cave and lighted by means of smouldering branches from a burning wood. This turned the cave into a cozy little room.
And then one evening a dead chicken fell into the fire. It was not rescued until it had been well roasted. Man discovered that meat tasted better when cooked and he then and there discarded one of the old habits which he had shared with the other animals and began to prepare his food.
In this way thousands of years passed. Only the people with the cleverest brains survived. They had to struggle day and night against cold and hunger. They were forced to invent tools. They learned how to sharpen stones into axes and how to make hammers. They were obliged to put up large stores of food for the endless days of the winter and they found that clay could be made into bowls and jars and hardened in the rays of the sun. And so the glacial period, which had threatened to destroy the human race, became its greatest teacher because it forced man to use his brain.
