In a Japanese village lived a man who had two sons. When the sons were grown up, each brought home a wife from another village long distance away. The farmer-in-law was very pleased with the daughter-in-law. So the lived very happily together.

After several months the young wives asked their father-in-law to allow them to go and visit their relatives and friends. After having refused them again and again, he at last agreed to let them go. But he wanted to know whether they loved him or not. So he asked each to bring a present for him. The older daughter-in-law was to bring fire wrapped in paper and the younger one was to bring air wrapped in paper. If they failed to bring these presents, they were asked not to come back again.

They did not think it would be difficult to bring such presents. So...