Object: A rock (as large as possible)

Good morning, boys and girls. A missionary in Africa was traveling with two African friends. They came to a pile of stones and each of his friends picked up a stone. They advised him to do the same. "Why should I pick up a rock and carry it," I asked. "You'll need it," replied one of his friends. "I can't see any use of carrying a burden like that," said the missionary. He walked on refusing to pick up a stone. Soon they came to a swollen river. The two African men walked right on out into the river and the stones weighted them down and kept their …