Purpose: To help children understand one way whereby God speaks to people today.

Materials: A water goblet, made of thin glass. Fill about one-third full of water.

Special Preparation: Before making this presentation, practice producing a sound with the glass. Dip your finger in the water to moisten the tip of it. Then slowly run your finger--palm down--around the rim of the glass. Vary the pressure and speed until you produce a high pitched sound. A light touch works best.

Lesson: By rubbing your finger around the rim of this glass a vibration is set up in the wall of the glass. This sound is then amplified by the glass so t…