Before man discovered fire, the only heat and light he had was provided by the sun. Since he couldn’t control this, he was quite helpless in dealing with cold and darkness.

Probably more than 100,000 years ago, he discovered fire. Then he began to notice that some materials burned better than others. Perhaps he observed that fat dripping into the fire from roasting meat burned brightly. As time passed, man began to select materials which, when burned, provided better light.