What You Need:
- Clear, plastic bottle (at least 10 inches high)
- Denatured alcohol
- Blue food coloring
- Vegetable oil
- Fill the bottle three-fourths full with the denatured alcohol.
- Add blue food coloring (make it a deep blue color).
- Fill the bottle with cooking oil, leaving a small space at the top.
- Glue the top on for safety. The substances will not mix and the water will move like a wave over the oil when moved up and down.