Pieces of broken pots are scattered over the desert hillsides of the Southwest. The Indians there treat them with respect — Every piece of clay is a piece of someone’s life, they say. And the children try to imagine those lives that took place in the desert they think of as their own.Clay has its own small voice, and sings. Its song has lasted for thousands of years. And Byrd Baylor’s prose-poem as simple and powerful as the clay pots, sings too.