When they poured water on the Wicked Witch of the West in The Wizard of Oz, she started to shrink, screetching, “I’m melting! I’m melting!” and it seemed like a really unpleasant experience for her.  Another way to describe the conversion from evil green lady to a pile of black clothing might be to say that the Wicked Witch of the West underwent a phase change, although “I’m phase changing! I’m phase changing!” doesn’t really have the same ring to it so I respect the script writer’s choice of words.  We benefit from the phenomenon …